The worst epidemic of the West Nile virus (WNV) in the United States since the disease first appeared in 1999, with 509 cases reported and 20 deaths across the country, has forced Texas, the worst-hit state, to declare a state of emergency earlier this month, The Guardian reported. The State announced that it will begin aerial spraying of pesticides, which has some local officials worried.

Last week (August 24), the Journal of the American Medical Association (JAMA) released a tip sheet and opinion for doctors and patients explaining how to spot symptoms of the disease and discussing the importance of mosquito spraying. One article states that given the long term consequences of the more severe version of the disease, which involves the central nervous system and can result in paralysis and death, doctors should suspect that “anyone with unexplained fever from late June through September, the season when other causes...

Although some local government officials in Texas oppose spraying, doctors can only provide supportive measure to infected patients because the disease is caused by a virus, which can’t be treated with antibiotics. “Public health action,” such as educating the public and truck and aerial insecticide spraying, “is crucial,” Robert Hayley, a University of Texas Southwestern Medical Center epidemiologist, wrote in JAMA.  In fact, Hayley said, aerial spraying delivers a much lower dose of insecticide than spraying by truck and on foot, and reaches the tops of trees, where the mosquito species that spreads the virus often resides.

Hayley concludes, “Given the effectiveness and safety of available control measures, this is a good time for all local governments to reevaluate and establish policy for response before it is their turn to be visited by WNV.”

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