<P> The U.S. federal government revised its diagnosis from St. Louis encephalitis to West Nile virus on September 27, 1999, citing research by Dr. Duane J. Gubler, a C.D.C. expert on arborviruses, as well as several bird deaths in the Bronx, located to the north of Queens . </P> <P> Dr. Deborah Asnis was credited by health experts with the early identification of West Nile virus in the United States . Her actions likely prevented a more widespread outbreak . In their 2003 book, "The New Killer Diseases: How the Alarming Evolution of Germs Threatens Us All," authors Elinor Levy and Mark Fischetti praised Dr. Asnis' response to the symptoms, writing that, "Asnis did something other doctors might not have bothered to do ." They elaborated that, "One of the worst problems with our disease - detection system is that many doctors never report cases of strange symptoms, either because they are unsure of the disease they are facing, they're ignorant of the reporting requirement, or they simply never get around to it . Deborah Asnis was highly conscientious ." </P> <P> During the years between 1999 and 2010, an estimate of 3 million people have been infected in the United States . Highest incidence rates are observed in states of the central great plains, with South Dakota, Wyoming and North Dakota leading in incidence . </P> <P> During the 2012 West Nile virus outbreak in Texas, USA, 1,868 cases were reported . Male patients, persons> 65 years of age, and minorities were at highest risk for neuroinvasive disease . At total of 1,868 cases including 844 (45%) WNND (West Nile neuroinvasive disease) cases and 89 deaths (case - fatality rate 5%). Dates of onset ranged from May 1, 2012, through December 6, 2012 . The outbreak peaked during week 33 (mid-August) with 225 reported cases, which is historically the same peak for all reported WNV cases in Texas during 2002--2011 . The median time from date of symptom onset to date of official report to TxDSHS was 27 days (range 6--274 days). Of the 254 counties in Texas, 135 (53%) reported a WNV case . The overall incidence rate for the state was 7.8 cases per 100,000 population . Almost half of the cases were reported from the northeastern quadrant of the state, including the Dallas / Fort Worth metroplex (902 (48%) cases): Dallas (396 (21%)), Tarrant (259 (14%)), Collin (64 (3%)), and Denton (183 (10%)) counties . These 4 counties had a combined incidence rate of 16 cases per 100,000 population . </P>

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