April 29, 2016

Zika Virus Outbreak: Research Funding, Commercial Test, U.S. Risk Map

In the ongoing outbreak of Zika virus infection across parts of North and South America, there are several developments which signal increasing concern over the exact impact and geographic reach of the virus (the first death in the U.S. linked to the virus has been reported). At least 55 countries report Zika outbreaks, according to the World Health Organization. The virus is spread by mosquitos, specifically the Aedes aegypti. In the U.S., 426 cases of Zika-infected individuals have been reported. Although a course of infection may be mild and easily resolved in most individuals, Zika has become a high-profile infectious disease because viral infection in pregnant women has been linked to an increased risk of microcephaly in offspring. There are suspicions that more developmental risks to the child of an infected mother may exist, possibly unknown and only seen as development unfolds. In general, the mosquito thrives in warm and tropical climates, but seasonal weather patterns can shift the field of exposure. NASA scientists and other colleagues have published an Aedes aegypti risk map of the U.S., showing that a wide swath of the eastern U.S. is potentially susceptible to mosquito (and thus virus) spread, especially in the upcoming summer of 2016; the potential spread goes north as far as New York City. A commercially available test for detection of the Zika virus received an Emergency Use Authorization (EUA) from the FDA (the Quest Diagnostics Zika RT-PCR test). A current legislative battle over possible increased funding for public health responses to Zika reached a stalemate before Congress adjourned. One bill calls for $1.6 billion in supplemental funding for dedicated Zika virus research and public health capabilities, but is encountering Republican opposition. Some of the political infighting over a federal response to the Zika outbreak recalls earlier conflicts during the Ebola virus crisis. However, the Zika virus is already in the U.S., cases are officially documented, and the upcoming summer portends more infections, not less. The 2016 Summer Olympics in Brazil this summer have already caused concern among attending athletes; the current understanding of transmission suggests that Zika virus cases in the U.S. are largely explained by travel to countries with high risk of infection; that fact will also impact the Olympics participation. No effective treatment or vaccine for the Zika virus is yet developed; increased NIH funding would certainly allow research to expand. Another target for intervention is to reduce the Aedes aegypti mosquito population; already, a British biotechnology has produced a genetically engineered (GE) mosquito that is reproductively crippled and is hoping to conduct trials in the U.S. An upcoming post will examine that option in more detail.

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