Federal health officials are planning to start a blood donation screening process for the West Nile virus.
They made the announcement after the Centers for Disease Control said the virus could be spread through blood transfusions.
According to the CDC, the virus can survive in donated blood for several days.
A woman in Mississippi caught West Nile after getting transfusions from three peopel who had the virus.
The disease is most often spread through mosquito bites. Health officials say they'll start a screening process as soon as they can develop a reliable test.
That could be tough.
West Nile is harder to detect than HIV because there are relatively small amounts of the virus in tainted blood.
The West Nile virus was first detected in Colorado last month. The first human case in the state was reported Tuesday.