Scientists develop a cheap, smartphone-based test for Zika
Many a world traveler questioned their tropical vacation plans last year after the mosquito-borne Zika virus started making headlines. To test for the disease, which has been tied to a surge of microcephaly cases in infants, physicians look for flu-like symptoms and your recent travel history. They then confirm a diagnosis by testing a blood or urine sample. For modern Western travelers, that’s no big deal. But what about those who may not be able to afford a doctor’s lab tests or clinics unable to afford costly testing equipment in the first place?
Researchers at Sandia National Labs have come up with a diagnostic test for Zika that’s smaller and cheaper than current testing equipment. In fact, it’s based around a smartphone. Like existing tests, it hinges on a blood sample, but then the blood is put through a process called loop-mediated isothermal amplification (LAMP). In this process, a sample mixed with “a few carefully designed biochemical agents” is heated to 150 degrees Fahrenheit for 30 minutes. Any positive DNA fragments in the sample will glow, tagged by a light emitting fluorophore molecule. To check for those positive, glowing reactions, your smartphone (situated over the LAMP box) performs some image recognition using its camera and a dedicated app.
This technique is leagues cheaper than current testing solutions, whose equipment can cost upwards of $20,000. That equipment also tends to be quite large, which, while appropriate for laboratories, isn’t ideal for small clinics. A prototype of this LAMP box, by contrast, can be held in one hand. It’s also faster, with the process only taking half an hour.
“There are billions of smartphones in the world, even in developing countries, and this tool doesn’t require the highest-end smartphone on the market,” chemical engineer and paper lead author Aashish Priye said. “It only needs to have an optical sensor and be able to run the app.”
This solution is just one of a growing number of lab tests and medical diagnostic tools that are moving to the smartphone. For example, in 2014, researchers at the University of Cambridge developed an app that paired with testing strips to monitor a variety of medical conditions. And in 2015, Columbia University researchers developed a mobile-based lab-on-a-chip that could check for HIV and syphilis in only 15 minutes—and cost only $34. Armed with a suite of relatively cheap accessories, physicians working in remote locations could perform a variety of useful, accurate tests minus the lab (and with a fraction of the legwork).
In this case, the app and LAMP box could be used to check not only for Zika but also dengue and chikungunya. These diseases are all spread by the same type of mosquito and result in similar symptoms. Outfitted with these types of tools, clinicians will hopefully be able to identify and treat pandemic threats more quickly and more successfully in the near future.
Source: The Daily Dot
This from Daniel Chang of the Miami Herald.
Florida health officials on Monday reported one more locally acquired Zika infection in a person who felt no symptoms but who was tested for the virus in February.
The person likely acquired Zika in Miami-Dade in 2016 after “multiple exposures” to areas where mosquitoes were spreading the virus, the Florida Department of Health reported, adding that the state had just received confirmation from the federal Centers for Disease Control and Prevention.
In addition, Florida reported four new travel-related Zika infections, raising the total number of cases for 2017 to 29 people, including one locally acquired case from Miami-Dade. Among the 29 cases reported in Florida this year are 13 pregnant women and two people whose source of infection is undetermined after a health department investigation.
Pregnant women are considered to be at the greatest risk from Zika because the virus has been shown to cause microcephaly and other neurological disorders in children born to mothers infected while pregnant. The frequency of Zika infections in Florida has declined over the winter, but public health experts expect the virus to resurface as the temperature warms and rain increases.
Source: Miami Herald
Sperm donated in three Florida counties since June 15 may be infected with the Zika virus, the United States Centers for Disease Control and Prevention cautioned Monday.
“When semen is donated it can be stored frozen for periods of time. It does not necessarily inactivate Zika, so it could be stored in tissue banks, used subsequently and people should be made aware,” said Dr. Peter Marks, director of the Center for Biologics Evaluation and Research at the US Food and Drug Administration. He went on to say having this information can help individuals make informed decisions and they “might want to use these donations from other sources.”
Sources other than the 12 sperm banks in Miami-Dade, Palm Beach and Broward counties of Florida, that is.
The agency had previously designated only Miami-Dade County as an area to take precautions after the first local transmission of the virus in the continental United States was confirmed in the Wynwood neighborhood of Miami in July. The area was declared Zika free in December.
However, the CDC is now warning anyone in Palm Beach and Broward counties to also consider themselves at an increased risk for the virus. This applies to anyone who has traveled to or between these three counties since June 15, 2016, a change from previous guidance that designated June 29 as the start of the increased risk period.
It is possible that someone could have Zika without knowing, because an estimated 80% of those infected have no symptoms. When symptoms occur, they can include fever, rash, joint pain and red eyes, and they can last from a few days to about a week.
Pregnant women are at greatest risk because they can unknowingly pass the virus to their fetus, causing devastating consequences including miscarriage and neurological deficits that last a lifetime.
Because the virus can also be sexually transmitted, pregnant women or those trying to become pregnant have been advised to avoid unprotected sex with a partner who has been infected or who has lived in or traveled to an area where the virus is circulating.
The ongoing investigation into reported cases of the virus in Florida has found that residents of Miami-Dade, Palm Beach and Broward counties travel frequently between the counties and either forget, or fail to, consider that they’ve visited an area of increased risk, thus not realizing they could be infected.
Women who live in these three counties who have become pregnant since June 15 are advised to speak with their physicians about the potential increased risk as are women who want to use a sperm donation from a donor in these counties, advised Dr. Denise Jamieson, incident commander for the CDC Zika emergency response and chief of the women’s health and fertility branch at the CDC’s division of reproductive health.
CDC officials said they are acting only out of an abundance of caution and there have not been any reports of the virus being transmitted through donated sperm.
“Now we understand more than we did months ago is that evidence of the Zika virus is present in semen for up to three months after a man is infected and people may not have accurately recalled potential exposure [to the virus] especially if in a local area,” said Dr. Matthew Kuehnert, who is part of the CDC Zika emergency response team and director of the CDC office of blood, organ and other tissue safety.
Unlike blood donations, which are routinely screened for the virus in the United States, there is no available test to screen semen for Zika. The existing test is still in the research phase and accuracy is being assessed, which is why men in these counties should not donate sperm. Their donated sperm may be infected.
The Florida Department of Health last reported a case of local transmission of the virus on March 2. However, that report included confirmation of two cases from October of last year. A third case was also reported then but this was an individual who donated blood in January and through routine blood screening was found to have previously been infected but no longer had an active case of the virus.
The CDC media statement
Florida health officials confirmed three new locally acquired cases of the Zika virus in Miami-Dade County on Thursday but said they will not lead to any new Zika zones in the city or nearby South Beach.
“Two are cases that had samples collected in October as part of our ongoing investigation and the department just received confirmatory testing back from CDC.,” according to the Florida Department of Health, which added that both cases have been added to 2016 data.
“The third case reported no symptoms, but screening conducted after blood donation in January showed evidence of a past infection,” officials added on Thursday.
“This individual had multiple exposures in Miami-Dade County and likely contracted Zika in 2016,” health officials explained. “Because the individual was asymptomatic, it is difficult to determine when infection occurred. Since the first positive sample was collected in January, this is considered our first locally reported case of Zika in 2017.”
State health officials, however stressed that Florida still does not have any identified areas with ongoing, active Zika transmission.
With the two new cases, the total number of Zika cases reported in Florida for 2016 stands at 1,384. So far in 2017, the total of Zika cases reported in Florida is 18.
Gov. Rick Scott announced on Dec. 9 that the final remaining Zika zone in the state had been lifted — an area of about 1.5 square miles between Eighth and 28th streets in South Beach.
“We will continue to see travelers bringing Zika infections into our state and so we must remain on alert and continue all the protective efforts that we’ve doing that have led to this success,” cautioned Philip, who also serves as Florida’s surgeon general. “That means continuing to use repellent, keeping your skin covered as much as possible …. And we cannot forget about the risk associated with sexual transmission.”
On December 2, 2016, the governor announced that the Little River zone in Miami had been cleared. That area included a one-square-mile stretch between NW 79th Street to the north, NW 63rd Street to the south, NW 10th Avenue to the west and N. Miami Avenue to the east.
In November, Scott gave the all clear to the Miami Beach area north of 28th Street to 63rd Street. Before that, he announced that the Wynwood area of Miami had also seen no new transmissions of Zika. This included the area of Northwest 5th Avenue to the west, U.S. 1 to the East, 38th Street to the north, and 20th Street to the south.
Despite Zika concerns, Florida set a tourism record last year with 112.8 million visitors.
Emergency Preparedness Leaders, National and Local Vector Control Officials, Healthcare Providers, Public and Private Sector Partners and Zika Virus Experts will once again gather to learn findings and solutions about the Zika virus from each other. This is all geared towards the improvement of their preparedness and response efforts in the event of a Zika virus outbreak.
The 2nd International Zika Virus Conference and Workshop once again provides experts, leaders from all government levels (tribal, local, state, federal), and other health officials a venue where they could share the best practices and the latest researches about the Zika virus to delegates coming from different parts of the world. Priority will be placed on identifying the responsibilities of stakeholders in order to improve global communication coordination and collaboration. The ZIKV conference will be held at the Hilton Washington Dulles Airport Hotel on March 29-30 followed by an all-day hands-on workshop on the 31st.
The 2nd iZIKVc will focus on the latest preventions, preparedness, responses and recovery measures being developed to address the transmission of Zika virus. The speakers and exhibitors are selected to present the widest possible range of perspectives—not only human but also physical, environmental, and social-cultural.
Speakers of the event include:
• Zachary S. Thompson
• Dr. Oscar Alleyne
• Dr. Lorrin Pang
• Dr. William N. May
• Phillip Goodman
• Phil Maytubby
• Vincent Cantu
Each day, the conference will offer papers on a wide range of topics including:
• Preparing Community Strategies
• Local Partnership and Participation
• Emergency Response and Hospital/Healthcare Coordination
• Prevention Education Efforts and Risk Communication
Panel discussions include:
• Mosquito Vector Surveillance and Control
• Health Department Response
• Zika Prevention, Community Engagement and Cultural Equity
• Community Strategies/Partnership
• Establishment and Implementation of a Scalable Vector-Borne Disease Response Plan at the Local Level
• Mosquito Response/State Level
• Defending Susceptible Communities from Spread of Arboviruses
• Mitigating Public Health Vulnerabilities
Click here for a free copy of the event brochure.
Scientists have found a way to sterilize mosquitoes that spread Zika virus and dengue fever, and thus to be able to control the insect population, according to research at Yale and Vanderbilt universities
According to a Yale press release, fertilization by infected male insects containing the common bacterium Wolbachia will fail unless the female also is infected with Wolbachia.
“Females inseminated by these males only lay dead (sterile) eggs,” said John Beckmann, a postdoctoral researcher in Yale’s Department of Molecular Biophysics and Biochemistry, in a press release. Beckmann is lead author of a paper in Nature Microbiology and contributing author of a related paper in the journal Nature. “If the sterilized males are released into problem areas we can eliminate insect populations.”
Zika, which causes severe birth defects, and dengue fever, which causes flu-like symptoms and occasionally leads to death, are spread by the Aedes aegypti mosquito. However, that mosquito does not naturally carry Wolbachia, the release said.
By inserting the genes from Wolbachia into males of the Aedes aegypti species, the mosquito population could be controlled, said Mark Hochstrasser, professor of molecular biophysics and biochemistry and of molecular, cellular and developmental biology, in the release. Hochstrasser is senior author of the Nature Microbiology paper.
Beckmann told the New Haven Register that each female can lay 600 eggs in two batches during her life cycle. If she is impregnated by a sterile male, within three generations, there would be millions of sterile mosquitoes, he said.
Yale’s Judith Ronau, a postdoctoral associate in molecular biophysics and biochemistry, is co-lead author of the Nature Microbiology paper. Vanderbilt’s Seth Bordenstein is senior author of the Nature study.
Source: New Haven Register
Scientists with Wayne State University say they are the first to publish research to show the Zika virus can damage retina cells in the eyes, and in some cases cause blindness.
“The key message of the study is that indeed the Zika virus can cause damage,” said Dr. Ashok Kumar, microbiologist and assistant ophthalmology professor with Wayne State University School of Medicine at the Kresge Eye Institute.
Dr. Kumar led a team which launched research in July to publish their study in JCI Insight, the Journal of Clinical Investigation Feb. 23.
Using mice Dr. Kumar says the Zika virus can infect and cause lesions in retina cells, causing damage and in some cases cause blindness. Their research showed the Zika virus mostly killed cells specifically lining the blood-retinal barrier, the retinal endothelium, and retinal pigment epithelium.
“Zika virus can actually infect those cells, and we did … studies and we found it can replicate in those cell types and ultimately it kills those cells,” said Dr. Kumar.
Their study builds on existing research published May 2016 in the Journal of the American Medical Association Ophthalmology that linked the Zika virus to eye problems. Researchers showed that some infants born with congenital Zika infection and microcephaly-or significantly smaller head and underdeveloped brain-in the northeast state of Brazil, Bahia, they also had problems in their retinas, other organs, and some hearing loss.
“Pretty much the whole eye can be infected with the Zika virus,” said Dr. Gary Abrams, ophthalmology professor with Wayne State University School of Medicine at the Kresge Eye Institute, who assisted Dr. Kumar with the clinical aspect of this study.
Dr. Abrams says about one third of infants born with Zika will develop eye issues they have discovered, whereas 15 percent of adults with Zika will have some sort of ocular impact, but most do not get a retinal infection.
“This is a virus that’s fairly pervasive: once the infection occurs it can be pretty much all over the body, including in the eyes, in the tears, and elsewhere,” said Dr. Abrams.
Currently, Dr. Kumar says they are continuing research in hopes of developing methods to track and treat Zika infections. According to the Centers for Disease Control and Prevention, there is no known treatment at this time.
“There are so many questions we don’t know,” said Dr. Kumar. “First thing is: how does the virus replicate? How long is it going to replicate? And what will be the visual outcome.”
“The big question really is that Zika virus was discovered in 1947, so it’s about 70 years, and why suddenly is it becoming so prevalent?”
Source: FOX 17 West Michigan
This just in from Daniel Chang from the Miami Herald.
The Aedes aegypti species of mosquito is believed to be the most capable transmitter of Zika. But University of Georgia ecologists have created a predictive model that suggests up to 35 species of mosquitoes can spread the virus, according to a study published Tuesday in the journal, eLife. Miami-Dade was the only county in Florida to have designated active Zika transmission zones during an outbreak in 2016, according to state health officials.
Zika may be spread by as many as 35 species of mosquitoes, including seven found in the United States, according to a forecasting model created by University of Georgia ecologists and published Tuesday in the journal eLife.
Most scientists, including those at the Centers for Disease Control and Prevention, believe Zika is primarily spread through the bite of an infected Aedes aegypti or Aedes albopictus species of mosquito, both of which are prevalent in Florida.
But University of Georgia ecologists suspect that there must be other types of mosquitoes capable of spreading Zika because an outbreak of the virus on Yap Island in 2007 was driven by a different species, Aedes hensilli — and because other viruses closely related to Zika are spread by more than nine mosquito species, on average.
The Georgia researchers created a model to test their theory, and using mathematical analysis, predicted that 35 species of mosquitoes may be able to spread Zika. Seven of those mosquito species are found in the United States.
University of Georgia researchers recommended their findings be used to prioritize mosquito species for further studies that would confirm their ability to spread Zika while the virus is still laying low.
Zika spread rapidly through Brazil and the Caribbean in 2015 and 2016, leading to a spike in babies with severe birth defects born to mothers infected with Zika while pregnant. Miami became the first city in the United States to have active spread of Zika by mosquitoes last summer, after months of people with travel-related infections were reported in the state.
But despite being named a public health emergency by the World Health Organization and by Florida health officials in February 2016, Zika remained little understood by scientists — including the science of how it spreads, University of Georgia researchers reported.
So far in 2017, Florida has reported four travel-related cases and no new local infections. In 2016, Florida’s health department reported a total of 1,325 Zika cases.
Source: Miami Herald
Sheridan county confirmed its first positive case of the Zika virus, contracted through a bq. mosquito bite in a Sheridan man while traveling in the Caribbean
A Sheridan County man tested positive for the Zika virus on Jan. 11 after traveling to the Caribbean earlier this month.
“(The patient) got it on a cruise in the Caribbean and got bitten by mosquitos,” said Dr. John Finley with the South Sheridan Medical Center Urgent Care Clinic. “When they got back they had headache, rash and fever.”
The patient went to one of Finley’s nurse practitioners on Jan. 8, then returned on Jan. 9 to meet with Finley, who took a blood sample for testing with the Wyoming Department of Health.
Surveillance Epidemiologist Katie Bryan with the Wyoming Department of Health confirmed the third case of Zika in a six-month period in Wyoming and the first in Sheridan County. Bryan said the case was an adult male who contracted the virus while traveling. The other two cases occurred in Laramie and Campbell counties in August 2016.
Testing for the Zika virus starts with one blood test. If that test comes back positive, no further testing takes place. With the Sheridan case, the blood test returned positive.
“This patient noticed because of the rash and that’s really why they came in,” Finley said.
Common symptoms of Zika the patient faced included a headache, rash and fever. For most, the virus causes minimal damage and requires little to no treatment.
“Being a virus, there really is no treatment for it. The disease is very minimal as far as when you have it,” Finley said. “Headache, you don’t feel good for a couple days and maybe a rash and then it all goes away. Many, many people who’ve had it didn’t even know it. You don’t feel good one day and the next day you’re fine, you don’t think about it.”
Treatment runs similar to regular treatment for headaches and fevers.
“Usually we just tell patients to make sure they stay hydrated, take some Tylenol for the fever and rest and it’s going to go away,” Finley said.
Zika remains a low-key virus for most but becomes a true scare if women become infected and are pregnant or plan to become pregnant.
“Babies can have several birth defects that are associated primarily with Zika,” Finley said. “These are awful things you don’t want to have.”
Microcephaly is a birth defect where a baby’s head is smaller than expected when compared to babies of the same sex and age, according to the Centers for Disease Control and Prevention website. Babies with microcephaly often have smaller brains that might not have developed properly. Other conditions include Guillain-Barré syndrome, which the immune system attacks the nerve.
“The current recommendations for women: If you’re pregnant or thinking about getting pregnant, stay out of the Zika places,” Finley said.
The Puerto Rico Department of Health and Centers for Disease Control and Prevention have developed a surveillance system called Zika Active Pregnancy Surveillance System used to evaluate the association between Zika virus infection during pregnancy and adverse outcomes during pregnancy, birth and early childhood up to 3 years old, CDC’s website reads.
The United States, specifically Brownsville, Texas and Florida, Mexico and a majority of South America reported active Zika virus transmissions.
Due to cold winter months in Sheridan, it remains highly unlikely others will contract the virus through mosquito-borne Zika virus transmissions.
While the risk associated with traveling to countries affected by Zika virus transmissions remain extremely high for pregnant or potentially pregnant women, men also need to take heed to potential transmissions through bodily fluids.
“The virus builds up in body fluids; tears, saliva, sweat, semen,” Finley said. “The semen is where it seems to like to live for a long time. Men, if they go (to infected areas), they should not, absolutely not, get a woman pregnant for six months.”
Prevention, in this case, includes abstaining from sexual relations or using birth control.
For those with planned visits to affected areas, awareness and prevention need to sit at the top of the packing list.
Finley suggests using insect repellent with DEET, wearing long-sleeved shirts and pants and remaining aware of surroundings day and night.
CDCs website also suggests checking latest travel recommendations for updates on affected areas.
Source: The Sheridan Press
The Fresno County Department of Public Health has confirmed that a female resident has been infected with the Zika virus through sexual transmission in a travel associated case.
The Health Department said The Zika virus spreads to people primarily through the bite of an infected Aedes species mosquito, but can also spread through unprotected sex with a person infected with Zika. Most people infected with Zika do not experience symptoms, but should take precautions to avoid sexual transmission, even if they never had symptoms, if they have been at risk for exposure.
Source: ABC 30 Action News
Despite a predicted slow down during the cooler winter season, the Zika virus continues plaguing Florida
The Zika virus is mainly transmitted by the aedes aegypti mosquito. But, Florida Department of Health Secretary Celeste Philip says there are not well-researched protocols for how to get rid of the mosquito.
“It’s different than the nuisance mosquitoes that most of us are familiar with in that instead of dusk and dawn—remember that messaging—they’re day biters,” she said, speaking last week to the Senate Budget committee. “Instead of being out and about in nature, they like to be in urban areas, close to people, inside homes, often times. And, so the way that you address, mitigate, and control the aedes aegypti mosquitoes is very different.”
Philip says one of the focuses in this year’s health budget is more funding for epidemiologists, who deal with controlling different types of diseases.
“As we’ve learned from our Zika response as well as in the past few years, there seems to be a new disease DuJour that the department is responsible for,” she added. “We’ve had Ebola, we’ve had MERS—which is a Middle East respiratory syndrome and have repeatedly had to depend on epidemiologists. And, what we find is we are able to respond very well to whatever that condition is, but some of the daily activities of epidemiologists, then there is a delay in some of that. And, so, we have now gotten to a point where we believe that this is an important investment for the state for us to have a strong epidemiologist workforce.”
So far, the state has confirmed about 1,300 Zika cases. That includes cases considered travel-related, locally acquired via Florida mosquitoes, and involving pregnant women.
And, Philip says health officials are already making plans to monitor those mothers and their kids, since Zika is associated with a severe birth defect.
“So, as we move forward, and we continue to work with healthcare professionals to learn more about Zika to make sure testing is available and that they have the resources that they need, to make sure we’re following up with those infants over the next few years, if not longer—that will be an important partnership as well as following up with the CDC,” she continued.
Meanwhile, the health department isn’t working alone.
Since the first report of local Zika transmissions, state Department of Economic Opportunity Director Cissy Proctor says her jobs agency focused on assisting and educating the business community.
For example, she says DEO officials along with members of the Small Business Development Center, or the SBDC went to the Zika hotspots of Wynwood and Miami Beach.
“So, this was a team on the ground that went around to businesses and knocked on their door and asked, ‘how can we help you? What can we do?’ The things that they needed were technical assistance. ‘What can we do if people are not coming to our restaurants, to our businesses?’ And, working with the SBDC, came up with some creative ideas,” said Proctor. ”For instance, if a company or restaurant didn’t normally cater or didn’t normally deliver, then maybe that is something that they would try to see if they could keep income and money coming in the doors, so they can continue to employ the folks in their restaurants and their business.”
As for the state’s tourism industry, Zika still hasn’t had a big impact. Proctor says that’s according to her partner agency, Visit Florida.
“So, Visit Florida began a tracking survey to determine the impacts of Zika on people’s perceptions,” she added. “So, to date, we have 20 weeks of survey information that has been collected. What we know is that from what we’ve heard from tourism leaders, and anecdotally as well as I’m sure you all have seen on the news that there were cancellations. But, the survey results showed that even with increased news that there were not a significant number of cancellations. So, what we’ve heard is ‘yes, we’ve seen the news. Yes, we are concerned. But, no we are not cancelling our vacation.”
In fact, Proctor points out Florida hit record setting tourism numbers in the third quarter of 2016, despite concerns over Zika.
Two new tropical disease-transmitting mosquitoes have been found in the state of Florida for the first time, according to researchers from University of Florida.
Entomologist Nathan Burkett-Cadena did not expect to find the Aedeomyia squamipennis and Culex panocossa species in Homestead as well as in Florida City on a research trip back in October. It is a sign that Florida is now becoming more conducive to tropical mosquitoes, especially as they are found near the mainland.
Both species are believed to transmit viruses to humans and lay their eggs on weeds that float in canals and drainage waters, warned Burkett-Cadena in a Miami Herald report.
Mosquito-Weary South Florida
While native to Central and South America, the mosquitoes likely arrived via plants and spread across South Florida canals and ponds. They are expected to grow in numbers soon.
“This would speak to some broader environmental changes that have caused Florida to be more accessible and hospitable to tropical mosquitoes,” the scientist said, pointing to global warming as the likely culprit and saying nobody had the species’ arrival “on their radar.”
Apart from climate change, increased tourism and global trade have probably made Florida a good destination for the exotic species, Burkett-Cadena added.
It’s a particularly bad time for the discovery in South Florida, as a Zika virus outbreak hit Wynwood and Miami Beach over the summer and extending into fall. The outbreak, with over 1,200 local and travel cases documented statewide, is caused by the Aedes aegypti mosquito.
While dry, cool weather paired with aggressive control measures has helped contain the mosquito spread, the disease is expected to return by springtime.
Severe birth defects in different places have mounted a full-blown Zika crisis. The virus takes the form of microcephaly in babies and kids, a defect characterized by smaller-than-normal heads.
The Centers for Disease Control and Prevention have issued numerous health and travel recommendations for people who are most prone to the virus and its dangers, particularly pregnant women. As of Nov. 18, the World Health Organization has lifted the Zika virus’ global health emergency status.
While no vaccine exists for the virus yet, researchers have identified seven key proteins within it that may have been instrumental in the extent of the outbreak’s damage.
The two new species also carry viruses and can easily conquer densely populated areas.
There are a number of differences between them, though: the Aedeomyia mosquito feeds mainly on birds, which transmit the West Nile, Eastern equine encephalitis, and other viruses, while the Culex panocossa is a confirmed vector for the Venezuelan equine encephalitis, which poses a deadly threat to kids and the elderly.
The latter also likely carries the local Everglades virus, which is typically detected in native Culex species. The virus is so far contained since the mosquitoes do not survive well outside the Everglades, but researchers are worried about the mosquito’s tropical kin starting to spread it.
The virus in its mild form can lead to flu-like symptoms and joint aches but can progress to encephalitis and occasionally trigger comas that have not so far led to mortalities.
With the recent discovery, the number of invasive mosquitoes found in Florida over the past decade has reached nine.
Source: Tech Times
Following the recent Zika outbreak in Miami-Dade County, a multidisciplinary team of physicians has published a case study describing in detail the nation’s first locally-transmitted case of Zika
The findings of the case study, titled “Cutaneous Eruption in a U.S. Woman with Locally Acquired Zika Virus Infection,” largely center on the skin rash associated with the then-23-year-old pregnant patient’s diagnosis and provide a glimpse of the skin manifestations of the Zika virus. The report may have implications for future Zika screening, diagnoses and linkage to care throughout the United States and abroad.
“Dermatologists and clinicians had an idea of what the Zika rash looked like, but it wasn’t until the patient presented here that we were able to get an up-close and personal look and photograph the skin,” said Lucy Chen, M.D., a Jackson Health System dermatology resident and lead author of the case study. “Any doctor now has a visual sense of the rash to properly diagnose and refer patients to the appropriate specialists.”
The young woman whose case is detailed in the report was 23-weeks pregnant in July 2016 and had experienced three days of low-grade fever, a widespread rash and sore throat. The rash consisted of small pink bumps on the patient’s chest, back of her arms, legs, palms and soles, said Chen, who saw the patient upon admission. Her symptoms later advanced to muscle and joint pain. The patient tested positive for Zika although neither she nor her partner had traveled outside of the U.S. The case was confirmed by the Miami-Dade County Department of Health as the first non-travel-associated case of Zika in the U.S.
The virus was present in her system for two weeks in urine samples and six weeks in blood samples. Tests, thus far, on the patient’s infant show normal development, head size and intracranial anatomy, with no calcifications. The infant, who was born in October 2016, did not test positive for Zika.
Zika virus, a mosquito-borne virus, is transmitted by the Aedes Aegypti mosquito. As Miami-Dade County has the highest number of locally-transmitted and travel-related Zika cases in the U.S., University of Miami physicians at Jackson Memorial Hospital are uniquely positioned to document cases of Zika in adults and children and contribute to the growing knowledge of the virus, which has heavily impacted countries throughout Latin American, the Caribbean and parts of the U.S.
Christine Curry, M.D., Ph.D., who leads the care of Zika-infected pregnant women at the University of Miami and Jackson Health Systems, said the patient is “an example of how the virus can circulate in the body of a pregnant woman for more than the typical one to two weeks.” While there isn’t enough definitive evidence, Curry, an assistant professor of obstetrics and gynecology at the UM Miller School of Medicine, said some tests suggest that the virus may have a tendency to linger longer in pregnant women.
In addition to Chen and Curry, the case study was co-authored by George W. Elgart, M.D., professor and Vice Chair of Education for the Department of Dermatology and Jackson Health System dermatology resident Farheen Hafeez, M.D.
Chen said people who experience a rash often do not seek care from a provider until it has cleared up. However, as Miami-Dade County is ground zero for the U.S. Zika outbreak, physicians and health workers have been on heightened alert for patients presenting with symptoms associated with Zika.
UM and Jackson have taken a multidisciplinary approach to combating Zika transmissions, caring for patients and studying cases.
Chen and a team in the UM Department of Dermatology took a biopsy of the skin and noted seeing neutrophil cells, which Chen said are not commonly present with viral rashes but help fight infections.
“This is an interesting finding but we would need to study additional cases to determine whether these cells help distinguish Zika rashes from other viral rashes,” said Chen.
Source: Science Daily
Health officials say a child born in Travis County with microcephaly has the Zika virus
Austin health officials say a child born in Travis County with microcephaly has the Zika virus.
Austin Public Health Chief of Staff Bob Corona said the child was born last September in an Austin hospital, and tests confirmed the Zika virus this week.
Corona said the mother was infected in Central America, but it’s unclear if the mother was an Austin-area resident visiting Central America or a Central American visiting Austin.
State health officials say 294 people reported Zika-related illnesses as of Dec. 30, but only two of which were acquired in Texas. Twenty cases involved pregnant women, with two infants infected before birth. The first child born in Texas with Zika-related microcephaly, an abnormally small head, was last year in Harris County. The Zika virus was confirmed July 13.
Source: Time Warner Cable News Austin
To cap off a year that saw the Zika virus spread throughout the United States, The Centers For Disease Control made a grand, much-needed gesture. The CDC, using money granted by Congress earlier this year, has pledged close to $200 million to help fight the virus throughout the U.S. and its territories.
The money—which actually totals to $184 million—comes at a time where as many as 75 nations and territories have shown evidence of Zika infections. Approximately one year ago, that number was as small as 23.
As both the number of worldwide infections—and the measures intended to prevent them—continues to spread, the question remains: where do we stand with Zika?
Globally, only one new nation has reported a Zika infection since September, but that doesn’t mean the burden of the disease has lessened in countries that were already struggling. Even though the World Health Organization officially ended the status of the virus— which can cause severe birth defects in the brains of children born to infected mothers—as a global health emergency back in November, many countries are in it for the long haul when it comes to dealing with Zika.
In Brazil, for example, there have been 1,749 cases of babies born with defects in their nervous system, a problem that is estimated to cost the country around >$4 million per child
In the United States, these efforts may be working, as there has only been one new Zika case reported in the past three weeks. Despite this, research is continuing to reveal new ways that the virus can endanger pregnancies, making the task of stopping its spread just as important now as it was five months ago.
The virus first appeared in the U.S. in July, when Zika began to spread through infected mosquitos in Miami. Since then, infections have been reported in all 48 continental U.S. states.
However, almost all of these cases—there are 4,618 in total—have occurred through travel, with only approximately 200 infections in Florida and only a handful of infections in Texas spreading locally. Still, Congress is responding aggressively, as the CDC’s funding was only a small part of a $1.1 billion spending bill signed into law by president Obama back in September. The money is meant to serve a number of purposes, including vaccine research, mosquito control and studies on the virus’ effects on babies.
Source: Paste Magazine
There’s good news and bad news on the Zika virus front in Texas.
“The good news is, it’s been cold enough in most of the state that mosquito activity has dropped,” said DSHS Director of Media Relations Chris Van Deusen.
The bad news? “That’s not consistently the case in the Valley so there continues to be a risk of Zika spreading there,” he said.
So far, Texas has reported nearly 300 cases of Zika, with the vast majority related to travel to areas with ongoing Zika transmission. DSHS continues to receive weekly reports of new travel cases and has identified six cases transmitted by mosquitoes in Texas, all in Brownsville. Central and South America, as well as the Caribbean, continue to be Zika hotspots.
“That continues to be a concern for us, especially as people from the US travel there when it’s cold here,” Van Deusen said.
The federal Centers for Disease Control and Prevention recommends that all pregnant women who live in or regularly travel to Brownsville be tested for Zika, once in their first trimester and again in the second. They can do this at their regular pre-natal checkups or through their county health clinics.
Despite the advent of colder weather, DSHS still recommends Texans take precautions against mosquito bites by using an effective mosquito repellant and wearing long pants and long-sleeve shirts. And in addition to dumping any standing water in flower pots and the like, Van Deusen said it’s also a good idea to scrub containers where water collects to eliminate mosquito eggs that can lie dormant through the winter.
While the Zika virus is transmitted primarily through mosquito bites, it may also spread by sexual contact. The four most common symptoms are fever, itchy rash, joint pain and eye redness. While symptoms are usually minor, Zika can also cause severe birth defects, including microcephaly, in some women who become infected during pregnancy.
DSHS recommends pregnant women follow CDC advice to avoid traveling to locations with sustained, local Zika transmission, including all areas of Mexico. Pregnant women should also use condoms or avoid sexual contact with partners who have traveled to those areas.
To learn more and get updates about the Zika virus, visit texaszika.org or follow @TexasDSHS on Facebook, Twitter and YouTube.
Source: The Connection
Tony Gardner felt “pretty rough” after he was bitten by a mosquito carrying the disease in Guadeloupe
British actor Tony Gardner has revealed that he caught the Zika virus while filming the BBC crime series Death in Paradise in the Caribbean.
Known for his roles in Last Tango in Halifax, Fresh Meat and The Thick of It, the 52-year-old was taken ill after being bitten by a mosquito carrying the disease in Guadeloupe.
Speaking on comedian Sean Hughes’ podcast Under the Radar, Gardner said he felt “pretty rough” for a week after being bitten. He added that he and other crew members could make up “quite a lot” of the more than 250 Brits who are known to have caught the virus.
“There are now about 200 Brits who have had Zika,” Gardner said, “But quite a lot of them, possibly, come from the group of people that go out to Guadeloupe for six months a year to film."
“In retrospect I should have been more aggressive with the repellant,” he said.
He added: “About a couple of hours before I flew out I got a rash. And then for a week I wasn’t particularly well with joint pain and swelling… I just felt pretty rough actually for about a week.”
Gardner, who is a father and a qualified doctor, said that the virus was “not a problem for me because I’ve finished my family. It’s quite dangerous for people getting pregnant or men starting families.”
The production company behind Death in Paradise, Red Planet Pictures, said in a statement: “Information was provided on avoiding all mosquito-borne viruses and insect repellent was available on set at all times. Despite these precautions, a small number of the team were unwell after having been bitten.”
An outbreak of Zika in Brazil in 2015 was linked to instances of the birth defect microcephaly and women have been warned not to try and conceive for at least eight weeks after visiting areas affected by the virus.
Health officials confirmed a case of Zika virus in Willacy County, according to the Texas Department of State Health Services website.
The case is reported to be travel related. Zika virus cases have now been confirmed in all four counties of the Rio Grande Valley.
Zika is primarily spread through mosquitoes. Symptoms include fever, rash, joint pain and red eyes; however, most people infected don’t show symptoms or have mild symptoms. The virus has been linked to microcephaly, a birth defect where a baby’s head doesn’t fully develop.
Early cases of the virus in the Rio Grande Valley were confirmed in September and classified as travel related. In late November, health officials said a Zika case in Cameron County was transmitted locally by a mosquito. This led to voluntary urine tests of people living in the same area as the 43-year-old woman in the case. More cases of Zika were confirmed through these tests.
As of Tuesday, the state health department listed 16 cases of Zika in Cameron County, five cases in Hidalgo County, one in Starr County and one in Willacy County. Cameron County Health Authority Dr. James Castillo said there may be plenty of others infected, but only 20 percent of people with the virus are symptomatic.
So far, the only Zika cases in the state that were locally transmitted were found in Cameron County.
As of last week, Cameron County health officials haven’t found solid proof that infected mosquitoes are in the area. None of the thousands of mosquitoes trapped throughout Brownsville have tested positive for the virus; however, testing continues.
Dr. Castillo said they are relying on health experts’ educated guess and what is known about Zika to make determinations on each case. He pointed out it’s impossible to catch every single mosquito.
Florida health officials say they have one new case of a locally-transmitted Zika infection in Miami-Dade County.
Health officials said in a statement Wednesday that, despite the new case, the state doesn’t have any areas of active Zika transmission.
The statement says the Florida Department of Health is investigating to find out where the person was exposed to the virus.
Starting in late July, state health officials had identified four zones in the Miami area where the virus was spreading through local mosquitoes – the first such transmissions in the continental U.S.
But earlier this month state health officials declared all the areas were clear of continuing infection.
Researchers say some birth defects caused by Zika infections may not be apparent at birth but develop months later.
Source: NBC 2 Miami
In a world characterized by rising temperatures, deforestation and other human influences on the environment, the spread of infectious disease is a hot topic. Many recent studies suggest that environmental changes can affect the transmission of everything from malaria to the Zika virus — and it’s increasingly important to understand these links, scientists say.
This week, a new study has provided new evidence that environmental changes can increase the threat of disease. It concludes that unusually warm temperatures caused by 2015’s severe El Nino event — likely compounded by ongoing climate change — may have aided in the rapid spread of Zika virus in South America that year. And while there are many complex factors at play in the spread of mosquito-borne diseases, the study may help scientists better prepare for the kinds of future effects we might see in our warming world.
“The start of the mission was simple — trying to address where the risk will be, where is it going to move next, where could Zika happen on the planet on a global scale,” said Cyril Caminade, a research fellow at the University of Liverpool and the new study’s lead author. To that end, the authors designed a study that would help them determine how climatic changes have impacted the mosquito-borne transmission of Zika.
There are two main species of mosquito known to carry the Zika virus — Aedes aegypti, or the yellow fever mosquito, which is widespread in the tropics; and Aedes albopictus, or the Asian tiger mosquito, which lives in both tropical and temperate regions of the world. Scientists also believe Zika can be sexually transmitted, but the new study focused only on mosquito transmission.
For the study, the researchers collected published information on the distribution of these two mosquito species and how temperature variations can affect them. Studies suggest, for instance, that up to a certain point, rising temperatures can cause mosquitoes to bite more frequently. The researchers also collected global historical climate data from the past few decades and used all the information to build a model of Zika transmission worldwide.
The model produced an unusually high disease transmission potential in the tropics for the year 2015, including in Colombia and Brazil, the countries hit hardest by Zika. Similar results occurred between 1997 and 1998, one of the only other times on record to experience such a brutal El Nino event.
“[O]ur model indicates that the 2015 El Nino event, superimposed on the long-term global warming trend, has had an important amplification effect,” the researchers note in the paper.
A new report, published Thursday as a special edition of the Bulletin of the American Meteorological Society, provides some of the best evidence yet that climate change already has a hand in our worst weather.
The model also helped the researchers identify the ideal seasonal climate conditions for Zika transmission around the world. In South America, for instance, the model suggests that the potential for transmission should peak in the winter and spring.
In the southeastern U.S., on the other hand, summer is ideal. In fact, the model suggests this region has a high potential for disease transmission during this time, due partly to the high temperatures and partly to the fact that both mosquito species are found there.
That said, reports of Zika have been limited in the U.S. so far — and this speaks to the complexity of vector-borne disease transmission, Caminade said. Climate can certainly play a significant role in setting up the right conditions for an outbreak, but epidemics also depend on many other factors, including population density, access to healthcare and the use of pesticides and other anti-mosquito interventions in any given location. Some of these factors — which were not accounted for in the new study — can probably explain why there hasn’t been much Zika transmission in the U.S. so far.
Caminade also pointed out that after a population has been exposed to a mosquito-borne disease like Zika, a phenomenon called “herd immunity” often occurs — this happens when so many people have already been exposed, and developed an immunity, that there aren’t enough new people left to infect to continue the epidemic. This is the probably part of the reason we didn’t see Zika epidemics in other tropical parts of the world in 2015, despite the new study’s results. And some experts have suggested that herd immunity will likely cause the current situation in South America to burn itself out within a few more years.
But Caminade cautions that there’s still the potential for Zika outbreaks in other parts of the world where the conditions are right, including the United States and even southern Europe. The result would likely be milder than what’s been experienced in South America in the past year, but there’s “still risk,” he said.
According to Caminade, one of the study’s major takeaway points is that extreme climate conditions can lead to all kinds of unusual events — droughts, floods and wildfires are only a few examples — and disease outbreak is just one more potential disaster scientists should be looking out for when these conditions occur.
And such events may only be exacerbated by future climate change. Some studies have suggested that the kinds of “monster” El Nino events seen in 1997 and 2015 may be more likely in a warmer world, Caminade pointed out. But he added that scientists wishing to make more precise predictions about the future spread of disease must take a wide variety of factors into account — climate is just one of them.
“I won’t overplay the role of climate for the future,” he said. “It’s still a disease, and there are still parameters which are going to be very important.”
Source: The Times-Picayune
A sixth case of the Zika virus was confirmed in the Rio Grande Valley on Thursday.
Cameron County health authorities released the information Thursday stating a 14-year-old teenager was infected.
In total, 17 cases have been reported in Cameron County. Eleven of those are travel-related, while the remaining six were locally-acquired.
Cameron County Health Authority Dr. James Castillo said the teenager lives near East Price Road and South Padre Highway. The area is about a mile and a half away from the five locally-acquired Zika cases confirmed in the past weeks.
Dr. Castillo said the teen’s case is not connected to the other group. He said the Cameron County Department of Health and Human Services is testing those closest to the teen to make sure they aren’t infected.
“Our investigation so far – for the 14-year-old – is that no other people in his household have had symptoms. But we’re testing them,” he said.
Dr. Castillo said that unlike the first confirmed locally-acquired Zika cases, they won’t conduct door-to-door testing.
“We’re not going to be testing asymptomatic people outside of the household. So we’re not doing what we had done on the initial responses. Again, all of those tests were negative. We did find additional four cases, but only after they became symptomatic,” he said.
The physician said the city of Brownsville sprayed for mosquitoes on Wednesday and Thursday. He said he expects to see few cases per month. “I think local cases. I think we’re going to continue to have quite a bit of travel,” he said.
Dr. Castillo said people should see their doctor if they develop symptoms including fever, rash and joint pain. He advised Brownsville residents to wear long sleeves and spray themselves with repellent.
“Any place that the conditions are right and the weather is right for these mosquitoes, and you have travelers, you have the recipe for Zika transmission,” he said.
The health officials said this case doesn’t mean Zika is wide spread in Cameron County.
Source: KRGV 5 News
Amid fears of contracting the Zika virus, which causes birth defects, travelers are turning an eye to Hawaii for their vacations.
When NY1 traffic reporter Jamie Stelter and her husband, CNN anchor and correspondent Brian Stelter, were planning a December getaway, they nixed their usual locales.
“We like to go to Miami. We’ve been to Puerto Rico. Anything in the Caribbean feels fairly easy to do,” says Jamie Stelter.
But instead of a quick two- or three-hour jaunt to the beach, the Stelters went to Kauai in Hawaii — a 10-hour-plus journey from NYC.
The reason? Stelter would be four months pregnant in December and the mosquito-born Zika virus, she says — which can cause microcephaly and other birth defects — had infiltrated their go-to destinations.
“I [didn’t want to] take the chance, especially after what it took for us to have a healthy pregnancy,” says Stelter, 34, who has been public about her difficulties conceiving and IVF treatments.
In Kauai, “it was all pregnant women,” she says with a laugh. “It was a big trip, but we both knew we wanted somewhere that was warm and beachy and relaxing, and you really can’t go anywhere close.”
It’s not surprising that other New Yorkers also are clamoring to say aloha. The Centers for Disease Control and Prevention website reports that more than 200 locally acquired Zika transmissions have occurred so far in Florida, and more than 33,000 in Puerto Rico. The number of infections in other Caribbean islands, it notes, vary. Thus far, Hawaii has seen no locally acquired cases.
A Delta rep tells the New York Post that the industry has seen an increase in passenger demand to Hawaii from New York in the last year. And the Four Seasons Maui says the hotel’s New York guests jumped up 3.5 percent since last year.
This Christmas break, Allyson Stumacher broke a 15-year family tradition of hopping aboard a Royal Caribbean cruise leaving from Puerto Rico for a Norwegian Cruise in Hawaii due to Zika fears.
The 33-year-old mother of a 8-month-old and 4½-year-old was concerned what would happen if her youngest got bit, especially after they’d had a previous Zika scare.
“We did that Caribbean cruise [while I was pregnant],” says Stumacher. “When I got back, it was announced that there was Zika in those spots. The CDC flagged me and I had to go for blood tests and everything. I wouldn’t put myself in the same position.”
Hawaii visitors be warned: it’s good practice to check the CDC website for updated warnings before any trip to a tropical area.
For 30-year-old Katie, a West Village resident who asked that her last name not be used, Maui was one of the few warm-weather options being considered when her family planned her stepfather’s 75th birthday celebration this week.
“If not for Zika, we probably wouldn’t be going on such a long flight. It definitely adds an extra expense with 14 people traveling and we have one 3-year-old with us,” says Katie, noting that the five-hour time change can prove difficult for youngsters. “But at least we have an excuse to visit such an exciting and beautiful part of America.”
Source: New York Post
The Zika virus emerged as a global threat to pregnant women and their developing babies in the last year. What have we learned in 2016 and what can we expect from Zika?
ROBERT SIEGEL, HOST:
Zika – a little more than a year ago, most people had never heard of it. Then doctors in Brazil started to see lots of babies being born with malformed heads. They had microcephaly, a rare birth defect.
(SOUNDBITE OF ARCHIVED BROADCAST)
UNIDENTIFIED MAN #1: (Speaking Brazilian Portuguese).
LOURDES GARCIA-NAVARRO, BYLINE: Normally, in a year, he tells me, you’d have maybe three or four cases. In 24 hours, when we asked around, there had been 11 in the city. And that was a shocking enough number, he says, that we realized something very serious was happening.
SIEGEL: That’s NPR’s Lulu Garcia-Navarro reporting last December. The virus became an international health emergency. It spread to our shores. Here’s a father-to-be in Miami in August.
UNIDENTIFIED MAN #2: I want to be out planning to go baby shopping. And I’m waiting to see if my wife, who got sick with a rash after getting bitten by something on Miami Beach, has Zika or not.
SIEGEL: The more scientists learned about Zika, the more disturbing it seemed. NPR health correspondent Rob Stein joins us now to recap and tell us what to expect next year. And, Rob, let’s start by taking a step back. What did scientists know about Zika a year ago?
ROB STEIN, BYLINE: Well, you know, Robert, I’ve been covering health for decades, and I had to google Zika when doctors in Brazil first started to raise alarm bells about it. Researchers really knew very little about the Zika. It was so obscure and was thought to be pretty harmless. It hadn’t really been studied very much at all.
SIEGEL: Well, they’ve learned a lot about it since then. Bring us up to date about what’s now known about the virus.
STEIN: When I went to Brazil last February, the key question was – was Zika causing microcephaly? And now we know for sure, yes, Zika can cause microcephaly. And that makes it the first virus that’s spread by a mosquito that can cause a serious birth defect. And they also know how it does that. And the more scientists learn Zika, really, the more disturbing it becomes. They’re really – it’s becoming clear that microcephaly is probably just the tip of the iceberg.
SIEGEL: There are other problems caused by Zika.
STEIN: Lots of other problems. Babies can be born with deformed limbs. They can have seizures. They can be deaf – blindness. There’s a whole range of problems that Zika can cause.
SIEGEL: Well, those are things that we know or scientists know about Zika now. What are some things that they still don’t know?
STEIN: There are huge open questions. I mean, you know, a big one, obviously, is we’re still trying to develop a vaccine. And there’s some promising work going on there, but we’re not there yet. There’s no treatment for it, really. Another big question, I think, that a lot of women – pregnant women – have is – how risky is it, really? A lot of women catch Zika when they’re pregnant, but their babies turn out fine. And the big question is – how often does it cause microcephaly and other birth defects?
Now there some recent research came out just last week that started to give us a hint of what the risk might be. One study from the United States found the risk to be about 4, 6 percent maybe for microcephaly and birth defects, maybe as high as 11 percent if women are infected in the first trimester. But then there was another study out of Brazil that found that maybe close to half of pregnancies could end up with some sort of problem if women get infected when they’re pregnant. So the bottom line on that is we really don’t know.
And another big question is – is it going to cause problems later in life? We’ve discovered recently that the virus can continue to reproduce in the brains of babies after they’re born. That raises the possibility that could cause damage after they’re born and even in young children if they get infected.
SIEGEL: And looking ahead to next year, Rob, what can we expect to be hearing about Zika?
STEIN: Yeah, so scientists are keeping a close eye now on Latin America to see what’s going to happen. Are we going to see big epidemics, big outbreaks like last year? We might in places where we didn’t see a lot of Zika this past year. Doctors are also worried about Puerto Rico, where we saw a lot of infections this past year. And the women who got infected are starting to give birth now. Will we see a big upsurge in microcephaly? That’s a big concern. And also, you know, the question is on the continental United States – scientists think that we’re probably will continue to see Zika come back year after year. It’ll become kind of a chronic problem – not any big epidemics, but small clusters and outbreaks every year probably going forward for many years.
SIEGEL: OK. NPR health correspondent Rob Stein, thanks.
STEIN: Sure. Nice to be here.
As the holidays approach, we will be taking a short respite in our Zika news reporting, but will be back soon in the New Year.
Happy Holidays from all of us at Mosquito Squad
“Are you starting to think the Zika epidemic is the most confusing outbreak ever?
“Join the club.
“Since Zika surfaced on the global radar about a year ago, scientists have been trying to figure out if what seemed like a pretty paltry virus could cause serious birth defects if it infected a fetus in the womb and, if so, how often?
“There is really no doubt now that the answer to the first question is yes. Over the course of 2016 a lot of science has been published showing that the Zika virus wreaks havoc on a developing brain if it gets into a fetus.
“But the ‘how often?’ question — well, that remains a mystery. And two new reports this week — from top-flight research teams in top-drawer medical journals — not only failed to arrive at a consensus, they may have sown more confusion.
“A word of warning: Scores of studies like these are in the works and will hit the medical literature in coming months. That could mean the picture will become blurrier before it starts to come into focus.
“Still, Maria Van Kerkhove, an epidemiologist with the Pasteur Institute in Paris, is delighted so many studies are underway.
“’But as a scientist and as someone who has to communicate this, it’s a mess. Because all of these [studies] are at different stages, they’ve all been using different methodologies, so that’s confusing,’ Van Kerkhove said.
“Van Kerkhove has studied Zika, but she was not involved in the two articles that came out this week. Let’s head back to them.
“One looked at a group of 125 pregnant Brazilian women from Rio de Janeiro who were known to have been infected with Zika. Scientists found the pregnancies of 46 percent were affected in some way — the pregnancy was lost or the baby had some signs of brain problems. When they looked only at the babies born, 42 percent showed some issues that might have been related to Zika.
“The other study, conducted by scientists from the Centers for Disease Control and Prevention, looked at pregnancy outcomes in 442 women in the US who tested positive for Zika. The research team calculated the rate of bad outcomes — birth defects — at 6 percent.
“There’s a whole lot of daylight between those figures. And yet, interestingly, neither group is challenging the other’s findings.
“And they found some things that are similar. For instance, the rate of cases of microcephaly, in which an infant is born with an abnormally small head, was very similar in the two studies — 3 or 4 percent in total, 10 or 11 percent if infection occurred in the first trimester of pregnancy.
“But what about the differences?
“Before we answer that question, we need to provide some important context.
“A fetus infected today during the first trimester won’t be born for months. And in many cases it may take weeks or months after birth to realize that a baby can’t hear or can’t see or isn’t developing cognitively at the rate other babies are.
“As a result, the scientists who reported the high number of bad outcomes, the 42 percent, cast a very wide net when they were looking for problems Zika may have caused.
“That team, made up of researchers from Brazil and the US, included pregnancy losses (miscarriages and stillbirths), obvious birth defects linked to Zika, and even signs of possible brain changes seen using imaging technologies. The study was published in the New England Journal of Medicine.
“Some of those anomalies — for instance, cerebral palsy-like limb stiffness — will have an impact on the lives of these babies. But it won’t be known for a while if, or to what degree, some of the more subtle differences this group included will affect a child’s ability to function and develop, said Margaret Honein, the lead author of the second study, the one suggesting the rate of Zika-related birth defects might be lower.
“Honein, who heads the CDC’s birth defects branch, said the Brazilian study’s findings highlight why it will be critical to follow babies infected in the womb over time.
“It’s also crucial to get more data — and data that can be more easily compared.
“Van Kerkhove and other experts worked with the World Health Organization earlier this year to devise standardized protocols for studying Zika in pregnancy. The hope, she said, was that if lots of different research groups used the same template for their studies, the ensuing results would be an apple-to-apple comparison.
“Groups in a number of different countries appear to be using the protocols, she said. But not all are. So results that come out will look at slightly different groups of pregnant women or include more or fewer problems in the list of birth anomalies they count. And that will likely mean Zika risk estimates don’t cluster neatly around a tight range of numbers, at least not for a while.
“To complicate matters even further, there isn’t one accepted definition of microcephaly. That means the same baby could be counted as microcephalic in one country, and not in another.
“’This outbreak has been plagued by problems of definition and it’s hard when we’re using different surveillance definitions to compare data across locations,’ Honein said.
“So, about those two studies …
“STAT consulted a number of experts in epidemiology about these studies and there appears to be no single answer that explains the huge gap between the CDC number (6 percent) and the Rio number (42 percent). But here are some things that may be at play.
“The women being studied were different: The Rio study enrolled women who had a rash and fever, then tested them for Zika. That means they didn’t look at women without symptoms. Despite the fact the CDC study didn’t find a difference in the pregnancy outcomes between symptomatic and asymptomatic women, it’s a theory that experts haven’t given up yet and it needs further investigation.
“The CDC study, on the other hand, enrolled women who had been to places where Zika was spreading and who tested positive for the virus. But Zika testing is notoriously difficult. If it’s not done during or very soon after the infection, you cannot be sure a positive test is a true positive. The test may be picking up antibodies to related viruses like dengue.
“That means the CDC study may actually include some women who didn’t really have Zika, which would make the virus’s impact appear to be less than it was. Preben Aavitsland, Norway’s former chief epidemiologist, said that’s a possibility, but it can’t go all the way to explain the big gap between the findings.
“Another way in which the two sets of women may have been different: geography.
“Scientists have been wondering if some unidentified condition or conditions in Brazil — which has had the highest numbers of microcephalic babies due to Zika — is making Zika’s impact there worse.
“An obvious thought is that dengue, a closely related virus, circulates there commonly. Some scientists have wondered if previous bouts of dengue would raise the risk for pregnant women infected with Zika, because it’s known prior infection with one type of dengue (there are four) can make a subsequent infection with another type worse. Still other scientists have theorized that dengue antibodies might actually protect pregnant women from Zika’s worst damage.
“The Rio study compared women who had previously had dengue to women who had not and saw no difference.
“But they did see an unusually high rate of birth defects and pregnancy losses — 11.5 percent — in the women they were following who did not contract Zika, their so-called control group.
“You wouldn’t see that high a rate of abnormal outcomes in pregnancies in the US, which suggests there are differences between the Brazilian women and the US women that haven’t been accounted for, Maia Majumder, a research fellow at HealthMap, noted on Twitter.
“The upshot is that, for now, even the experts cannot quantify for a pregnant woman what the chances are that her fetus will be affected if she contracts Zika. But they do know this: Pregnant women should try as hard as is humanly possible not to get infected with this virus.
“’We’re finding pretty high levels of abnormalities in [pregnant] women who are infected with Zika,’ said Van Kerkhove. ‘The exact numbers are not completely clear at the moment. But the studies are being done and we’re hoping to get a clearer picture in the coming months or years. I hope it’s not years, but certainly months.’