A Jackson County blood donor is the second person in Oregon to test positive for West Nile virus, according to public health and American Red Cross officials.
"The test indicates this person, who was not ill, was infected with West Nile virus," said Emilio De Bess, DVM, epidemiologist in the Oregon Department of Human Services (DHS).
"This person's blood donation will not be used," said DeBess. "The test was done as part of routine Red Cross screening of blood donation. The nation's blood supply has been tested for West Nile since July, 2003."
The blood supply is routinely tested for West Nile virus because recipients of blood and blood products can acquire the illness from an infected donor.
"This shows that the processes in place to assure safety of the nation's blood supply are working," said Mel Kohn, MD, state epidemiologist. "It does not in any way signify there is a risk of acquiring West Nile from giving blood. We continue to advise people to give blood, as there is always a need for it."
Any blood that tests positive is eliminated from the supply, according to Kohn.
"This case is a reminder to residents that they should get the habit of protecting themselves from mosquito bites," said Jim Shames, MD, Jackson County health officer.
"Many of the Culex mosquitoes, which are the primary carrier of West Nile, will survive over winter as adults," said Shames. "It's very important to eliminate breeding sites this fall and especially next spring."
DeBess said that in 2003, of those individuals identified as having an exposure to West Nile in blood screening 89 percent reported no symptoms.
Source: Oregon Department of Human Services