In November, the Centers for Disease Control and Prevention (CDC) reported that West Nile virus (WNV), an infectious disease that first appeared in the U.S. in 1999, can be transmitted via blood transfusions and solid organ transplantation. The agency also said that recipients of organ transplants and patients with compromised immune systems are more likely to experience “adverse outcomes” if infected with the virus. The information appeared online in CDC’s Morbidity and Mortality Weekly Report (MMWR) on November 20, 2009.
While nationwide blood donor screening for WNV has existed for several years, some weaknesses still exist in the system. “Although screening is extremely sensitive, current methods still do not detect all WNV-infected blood donations, and organ donors are not screened routinely,” explained CDC in the MMWR.
The report cites two probable cases of donor-linked WNV transmission, both through the Louisiana Department of Health in October 2008. This highlighted the need for an approach that emphasizes universal adherence to the most advance testing methods and better coordination among blood centers. “To increase the likelihood of detecting WNV-positive donations, blood centers should use the most sensitive screening criteria feasible and communicate frequently with nearby blood centers on screening results during times of high WNV activity in their geographic area. In addition, healthcare providers should consider WNND [West Nile neuroinvasive disease] as a possible cause of neurologic complications in patients after blood transfusion or organ transplantation,” said the report.
WNV is most commonly spread by infected mosquitoes that carry the virus. In the U.S., seasonal flare ups occur, primarily in the summer and fall. Individuals who contract WNV often exhibit relatively mild symptoms, including fever, headache, body aches, skin rash and swollen lymph glands; 80% have no symptoms. On the other hand, WNV can become very dangerous and even fatal if it enters the brain. The virus can cause (inflammation of the brain) or (inflammation of the tissue that surrounds the brain and spinal cord).
Read the entire report, “West Nile Virus Transmission via Organ Transplantation and Blood Transfusion—Louisiana, 2008”
Source: United Press International (UPI), November 19, 2009 and MMWR, November 20, 2009