A new study shows that West Nile virus infection has been transmitted though blood transfusion to 23 patients.

West Nile virus is an emerging infection which is being seen increasingly in the US. More needs to be known about how West Nile is transmitted, so adequate protection can be given to citizens.

Researchers for the West Nile Virus Transmission Investigation Team now report on the threat posed by blood transfusion. They identified 23 patients who had developed West Nile infection following transfusion with platelets, red cells or fresh-frozen plasma,. Ten of these were already immunocompromised because of transplantation or cancer and eight were at least 70 years old.

Sixteen blood donors were linked to these cases. Nine had symptoms before or after donation, five had no symptoms and two could not be traced. The donors did not have antibodies to West Nile at the time of donation. The researchers suggest that maybe it's time to use more sensitive detection methods for West Nile virus when screening blood donations.

Source

New England Journal of Medicine 18th September 2003