A study out of the University of Florida has put the spotlight back on the Zika virus. In research published in a scientific journal last week, Chelsea Smartt, a molecular biologist at the University of Florida Institute of Food and Agricultural Sciences in Vero Beach, reported finding Zika RNA in Aedes albopictus mosquitoes in Brazil.
Public health officials suspected that the Aedes albopictus could spread Zika. The research confirms that suspicion.
Aedes aegypti (also known as the yellow fever mosquito) and Aedes albopictus (the Asian tiger mosquito) both abound in Florida, according to the U.S. Centers for Disease Control and Prevention.
The CDC doesn’t rule out the threat of Aedes albopictus, but the agency says “because these mosquitoes feed on animals as well as people, they are less likely to spread viruses like Zika, dengue, chikungunya and other viruses.”
As for Palm Beach, Deputy Town Manager Jay Boodheshwar said the information about Aedes albopictus is nothing new.
Boodheshwar said the town in its public messaging has referred to both types of mosquitoes as potential Zika carriers, and said that both are active in Palm Beach. But the town has focused on aegypti “because that is the prevalent mosquito that carries the virus here on the island.”
Now that the annual hot and rainy season is returning, the town is preparing for another larvicide treatment of all catch basins on public property, Boodheshwar said.
The catch basins were treated last fall, but the larvicide tablets are only effective for six months, he said.
The public will be notified when the treatment is scheduled, he said.
State and federal officials said in December that Zika no longer was being actively transmitted in Florida. But public health officials say Zika is likely to return with summer rains.
Tim O’Connor, spokesman for the state Department of Health’s Palm Beach County unit, said the latest research won’t affect the health district’s efforts to fight Zika.
“The main prevention is avoiding mosquito bites,” O’Connor said.
Town Councilwoman Margaret Zeidman, who has helped spearhead Zika education and prevention on the island, said aegypti and albopictus are similar. Both are found in tropical and subtropical habitat. But albopictus, unlike aegypti, tolerates cooler climes, up into the Carolinas and New England, she said.
“It’s everyone’s personal responsibility to protect themselves from mosquito bites and to get rid of containers that might fill with water,” Zeidman said.
Containers that hold water should be turned over or treated with a larvicide, she said. Packets are available at Town Hall. To protect from bites, cover your skin with clothing or apply DEET, which is safe for everyone except babies 2 months old or younger.
Source: Palm Beach Daily News
As a presidential candidate last summer, Donald Trump promised to lead an aggressive fight against the spread of the Zika virus. He urged Congress to fund a proposed $1 billion-plus Zika response plan.
But now, the public health community is expressing strong concerns about President Trump’s commitment to maintaining and strengthening the country’s infectious disease prevention infrastructure.
Many credit Trump’s draft budget, released last month, for proposing the creation of a new federal emergency fund designed to rapidly respond to public health crises. That’s something public health leaders have advocated for years.
Creating such a fund would end the need to call on Congress to provide crisis funding when an infectious disease outbreak occurs, as happened with Ebola and then Zika.
“There could be events quite frankly where (having an established emergency fund) could be the difference between a successful response and a failed response,” said James Blumenstock, chief program officer for Health Security for the Association of State and Territorial Health Officials.
Yet the Trump budget lacks details on how much money the administration would appropriate for the proposed emergency fund, or how the president wants to pay for it.
If Trump dedicates new funding, then it has the potential to be a powerful tool to aid prevention and response effort in emergencies, experts say. But if funding comes from cutting other public health programs, they say its potential impact would be greatly reduced.
“Any significant reduction in any program that (the Centers for Disease Control and Prevention) administers will have a cascading effect on state and local health departments and would result in a reduction in prevention activities in the communities,” Blumenstock said.
Establishing an emergency fund would not be enough to assuage larger concerns among public health experts over Trump’s move to repeal and replace the Affordable Care Act and impose other domestic spending cuts that could undermine prevention and response efforts.
Included in the president’s draft budget was a proposal to cut the National Institutes of Health by $5.8 billion. The NIH has been the leading funding source for vaccine research and development for several infectious diseases that have had outbreaks in recent years, including Ebola and Zika.
“If you defund the scientific infrastructure in general, all aspects are going to have to suffer and that includes preparedness for new diseases as well as research and therapy for existing diseases,” said Dr. David Freedman, professor of medicine and epidemiology at the University of Alabama at Birmingham.
Trump’s skepticism about the human-caused sources of climate change is reflected in his proposed 31% cut to the Environmental Protections Agency’s budget, which would force layoffs of an estimated one-fifth of the agency’s workforce. Climate change have been linked to an increased risk of infectious diseases.
Extreme weather events coupled with milder winters as global temperatures rise have created environments that are breeding ground for diseases, including mosquito-borne infections, that traditionally have spread only in the tropics but now are found in the U.S.
“It’s been one of the warmest winters on record, and that’s good for the Aedes Aegypti (mosquito) but not good for us,” said Dr. Peter Hotez, dean of Baylor College of Medicine’s National School of Tropical Medicine. “I’m quite worried that all of that means that it’s going to be a pretty bad Aedes Aegypti season this spring and into the summer, and that means there’s a pretty high risk for a Zika virus transmission.”
Even seemingly unrelated Trump policy decisions could have large public health ramifications. A repeal of the Affordable Care Act would not only mean a loss of health coverage for millions but also would eliminate the CDC’s Prevention and Public Health Fund. Created under ACA, the fund provides more than $930 million for CDC programs, accounting for 12% of the agency’s total annual budget.
A loss of the that funding would mean slashing $40 million from the CDC’s Epidemiology and Laboratory Capacity for Infectious Disease Cooperative Agreement program (ELC), which provides funding to public health laboratories around the country to quickly respond to emerging infectious disease threats.
The ELC program receives around half of its annual funding through the ACA’s Prevention and Public Health Fund. Program funds played a crucial role in helping state laboratories rapidly test suspected Zika samples months before Congress approved emergency federal funding last year.
Repealing the ACA and the prevention fund would eliminate ELC’s nimble ability to address public health concerns like Zika before lawmakers can react, said Peter Kyriacopoulos, senior director of public policy at the Association of Public Health Laboratories.
Erasing the prevention fund also would be a big blow to the CDC’s immunization program, which receives more than $324 million for states to improve their immunization infrastructure and increase vaccine coverage among children.
It’s questionable whether Trump’s proposed budget would have an immediate impact on the response effort to the spread of Zika this season. Many state and local public health departments already have received at least a portion of the $1.1 billion in emergency Zika funding approved by Congress last year.
But the question remains how the Trump budget cuts would affect the nation’s response efforts once that money is used up, when a new disease threat could emerge. There is worry that if health departments were faced with an outbreak of Zika plus a sudden epidemic of measles or influenza, it could push some agencies beyond their limits.
“So far we have been extraordinarily lucky in this country to have sequential public health emergencies instead of simultaneous emergencies,” Kyriacopoulos said.
Freedman said a larger concern lies in the potential impact Trump’s budget cuts could have on efforts to recruit the next generation of scientists and researchers. “The best and the brightest aren’t going to pursue a career in science if there are no opportunities for either jobs or funding,” he said.
Source: Modern Healthcare
Jason, Jason, he’s our man. If he can’t fight ’em, no one can.
This update from Megan Molteni of Science.
Of the many great things promised by Crispr gene editing technology, the ability to eliminate disease by modifying organisms might just top the list. But doing that requires perfecting something called a gene drive. Think of gene drives as a means of supercharging evolution to, say, give an entire population of mosquitoes a gene that kills the Zika virus. The trouble is, organisms develop resistance to gene drives, much like they eventually outwit pesticides and antibiotics.
Researchers dedicate no small amount of time and thought to creating gene drives that can outsmart evolution because the potential payoffs are so great. The lowly mosquito transmits dozens of diseases that kill more than a million people every year, making it the deadliest animal in the world. Pesticides, mosquito nets, and medicine won’t solve the problem, but gene drives might—provided scientists can make them less likely to succumb to the genetic mutations that might render them useless.
In a paper presented today in Science Advances, Harvard scientists used computational models to test a means of doing just that. The resulting gene can spread to 99 percent of a population in as few as 10 generations, and persist for more than 200 generations without the mosquitoes (or any other population) developing a resistance. Although the researchers did not test their method by tinkering with real mosquitoes, their modeling creates a blueprint for anyone eager to build a more successful gene drive.
Simply put, a gene drive makes a specific gene spread through a population more rapidly than would happen through nature alone, something geneticists refer to as “super-Mendelian inheritance.” Typically, this means inserting a bit of DNA into the genome of an organism—say, Aedes aegypti, the primary transmitter of the Zika virus. When the modified, or transgenic, mosquito mates with a wild mosquito, their offspring carry one one copy of the “drive gene” directly opposite its natural counterpart. The drive gene snips out the normal gene and inserts a copy of itself, doing this over and over and over again until every mosquito carries two copies of the drive gene—and therefore, resistance to Zika. That’s the idea, anyway. But because nature is imperfect, mistakes happen. More specifically, mutations happen. The very act of cutting out the normal gene makes the whole system more susceptible to mutations. And if enough of them add up over time and across a population, the drive gene can actually become recessive.
To fight back, science must develop a gene that works even if it isn’t perfectly copied, says computational biologist Charleston Noble, the paper’s lead author. “The trick is to decouple the cost of resistance and the cost of the drive.”
Noble’s team suggests doing this through a technique called recoding that genetic engineer and paper co-author George Church is developing. Because of redundancies in genetic code, there are times when you can do things like change a C to a T or a T to an A and still get the same proteins even though the DNA sequence is different. To offer an oversimplified explanation, it means you can create a drive that targets a gene essential to survival or reproduction. If the drive inserts smoothly, great. The gene drive drives on. If it doesn’t insert itself smoothly, no problem. The mosquito dies, or does not reproduce. And, because the new code for the essential gene doesn’t exactly match the target it replaced, it won’t get snipped itself.
“This kind of approach is definitely the direction the field is going to have to go,” says Philipp Messer, a molecular geneticist whose lab at Cornell is among the few testing gene drives in insects. “Whether or not it works experimentally is still an open question.” You can rattle off countless reasons why a method that works beautifully in computer modeling might utterly fail in the wild. Just one example—Noble’s simulations assumed an infinite number of mosquitoes all equally likely to breed with each other. Here in the real world, oceans and mountain ranges and other natural barriers might create populations the gene-driven mosquitos can’t or don’t reach.
Plus, not all bugs evolve resistance equally. Even within a single species, variations in individual genomes make it hard to predict how effectively a drive gene will insert itself into a population. “All these models assume there’s one fixed rate at which these things arise,” Messer says. “But that doesn’t seem to be the case.” Right now, Messer is looking at the rate at which resistant mutations occur in a Drosophila gene drive system. That work remains under peer review, but his lab is already finding mutation rates much higher than previously reported. That suggests the battle against gene drive resistance is far from over, even with an arsenal that includes tools like Crispr.
With cold winter weather the only major obstacle to the Zika virus becoming America’s first pandemic since the 1957 Asian Flu, ground zero for a potential pandemic is now the West Coast.
The California Department of Public Health released an emergency warning on March 31 that two invasive (non-native) mosquito species named Aedes aegypti (the yellow fever mosquito) and Aedes albopictus (the Asian tiger mosquito), which are known to carry Zika, dengue, chikungunya and yellow fever, have now been found in 10 California counties including Fresno, Kern, Imperial, Los Angeles, Madera, Orange, Riverside, San Bernardino, San Mateo and Tulare.
Unlike most of California’s native mosquito species, Aedes aegypti and Aedes albopictus only bite during the daytime. They are distinguished by their small size, and by their black and white stripes on their back and legs.
Aedes aegypti and Aedes albopictus are now common in Mexico, Central and South America, the Caribbean, and Asia. But the only documented U.S. cases of viral transmission from a mosquito to a human took place in South Florida and Brownsville, Texas last year.
The Center for Disease Control’s computer models correctly predicted that virus transmission would almost stop during winter due to the Zika vector mosquito populations drastically shrinking. They may, however, resurface in late next spring.
Those same simulation models expect California to be the ideal petri dish for a Zika virus pandemic, thanks to the combination of Aedes aegypti and Aedes albopictus mosquitos’ ability to lay their eggs in any small natural or artificial container holding water, plus historically heavy California rainfall and snowpack runoff expected to last until the end of summer.
The California Department of Public Health’s Division of Communicable Disease Control has “laboratory confirmed” a total of 529 cases of Zika infections in the state as of March 31. There were 2 new Zika infections reported in the last week, and officials expect the warming weather to accelerate the spread of the virus.
California has confirmed that 104 pregnant women contracted Zika, and 5 babies were born in the state with the virus. Birth defects directly related to Zika include microcephaly; brain damage from cranial calcium deposits; excess fluid in the brain cavities; brain damage affecting nerves and hearing; and inflexible muscles and bone deformations.
Although researchers have not confirmed any transmissions of Zika virus from mosquitos within the state, the virus is only symptomatic for only 18 percent of cases. Although Zika can cause severe sickness and death in adults, most infected individuals only suffer from mild flu-like fever, joint pain, muscle pain, headache and red eyes. Consequently, the Zika virus infection rate is drastically underreported.
But in an alarming development, there are six confirmed Zika infections in California women who acquired the virus through sexual transmission from an individual that traveled to nations where the World Health Organization already declared a Zika virus pandemic.
Hot zones for California Zika cases appear to be areas known for heavy tech immigration flows, with 155 in Silicon Valley and 150 in Silicon Beach.
The first human experimental Zika vaccine testing began in Houston earlier this week, and will soon begin in Miami and San Juan, Puerto Rico. Research scientists at the National Institute of Allergy and Infectious Diseases, which developed the vaccine, hope by June to have enrolled 2,000 volunteer test subjects across the Americas. Initial results will not be available until late 2017, and a vaccine will not be widely available for at least another two years.