New York State: 13 Years of Response to WNV and Other Arboviruses

Since 1999, when West Nile virus (WNV) was first detected in the Western Hemisphere in New York City, to 2013, New York State’s response to the disease has evolved.  From its discovery and media coverage and unknown consequences, to its return and expansion across the state, to now being “just another disease” that needs to be dealt with yearly, WNV has created numerous challenges at the state and local level.  These include reluctance to perform mosquito control when conditions may warrant, limitations of testing availability, limitations in mosquito identification, and the changing utility of different surveillance mechanisms.  Perhaps the biggest of these, however, is the current one of maintaining interest in vector surveillance and testing in a time of shrinking public health resources. 

There have been 667 human cases of WNV in New York State, and 53 of those have led to fatalities.  5744 mosquito pools have tested positive. There have been “good years” and “bad years” for WNV in New York, which has also tested our ability to maintain vigilance, not to mention resources.  New York has 62 counties, including the five boroughs that make up New York City.  At peak, 50 of these 62 were performing mosquito collections for surveillance and pathogen testing.  In 2012, just 17 counties were performing mosquito surveillance.  (New York does not have mosquito control districts.)

Eastern equine encephalitis (EEE), another arbovirus present in New York, provides an interesting contrast in terms of surveillance and control.  Whereas WNV impacts many more people, and is found across the state, and can have serious medical consequences, willingness to perform surveillance and control for WNV is tepid at best.  EEE on the other hand, is limited in geographic scope, and infects many fewer people, albeit with a much, much higher case-fatality rate.  There have been 5 human cases of EEE in New York since 1971.  All have been fatalities, and 3 of those have been children.  Surveillance and control for EEE is readily embraced.

These two mosquito-borne illnesses will be compared and contrasted, including discussing the history of each and the history of mosquito surveillance and control in New York State.