As of August 21, 1,118 cases of West Nile virus disease have been reported in the US. This is the highest number of cases ever reported for this 8 month period since the virus was first detected in 1999 and could become the largest US outbreak ever reported.
So far, 41 people have died from West Nile virus infection and about 630 people have developed the rare neuroinvasive form of the disease. Most of the outbreak is centered in north east Texas with 537 reported cases; of which ~ 300 cases are the neuroinvasive form.
It is estimated that over 94,000 people in the US have been infected with West Nile virus this year. Because West Nile virus can be transmitted by blood and cause serious illness in at risk patients, this epidemic poses an additional risk to the nations blood supply.
- Montgomery, SP et al. Transfusion-associated transmission of West Nile virus, United Sates 2003 through 2005. Transfusion 2006;46(12):2038-2046.
- Kightlinger, L et al. West Nile virus transmission through blood transfusion–South Dakota, 2006. MMWR Morb Mortal Wkly Rep 2007;56(4):76-79.