The current issue of The Archives of Neurology reports that organ transplant recipients who become infected with West Nile virus develop more severe neurological illness caused by the virus.
West Nile virus is an infection which in the last three years has had a significant impact in the United States. The virus is spread from birds to humans via mosquito bites. Symptoms include headache, fever and disorientation, and the disease can cause serious illness in a small percentage of infected people.
Until recently, human infection with West Nile virus, was limited to Africa, Asia and the Middle East. Since its arrival in the New York City area in 1999, human WNV infection has increased in scope and severity in the United States each year. In 2003, the U.S. Centers for Disease Control and Prevention reported more than 9,860 cases of WNV disease, which included 264 deaths. The article states that approximately 25,000 patients receive organ transplants in the United States each year. Transplant recipients are treated with long-term immune system-suppressing drugs that put them at greater risk for infections, including WNV.
B.K. Kleinschmidt-DeMasters, M.D., of the University of Colorado Health Sciences Center, Denver, and colleagues describe eleven transplant recipients (four kidney, two stem cell, two liver, one lung, and two kidney/pancreas) hospitalized with WNV encephalitis. All cases of WNV occurred between July 2003 and October 2003 and patients were seen in Colorado hospitals. All 11 patients received their organ five months to 15 years before being infected with WNV.