Public Health Dispatch: Investigation of Blood Transfusion Recipients
with West Nile Virus Infections
An investigation conducted by CDC, the Food and Drug Administration (FDA), the American Red Cross, and state
health departments in Georgia and Florida has confirmed transmission of West Nile virus (WNV) from a single organ donor to
four organ recipients (1). During treatment for injuries that eventually proved fatal, the organ donor received
numerous transfusions of blood products. However, the source of the organ donor's infection remains unknown.
Subsequently, CDC has been informed of four other patients with WNV infection diagnosed after receiving units of
blood in the weeks before WNV diagnosis. Because each of these patients resided in areas with high levels of WNV activity,
the most likely mode of infection is mosquito exposure. To rule out blood transfusion-associated transmission, investigations
are ongoing and efforts are under way to contact donors of blood given to these patients and other recipients of blood from
these donors for follow-up and WNV testing. In each instance, precautionary measures have included a withdrawal of
any remaining blood products obtained from the donors whose blood was given to these patients.
The investigations of the organ donor and four other transfusion recipient patients involve follow-up of approximately
100 donors. Initial testing by a quantitative polymerase chain reaction (PCR) assay
(TaqMan®) of stored blood
specimens obtained from the blood donors at the time of donation has been completed for two investigations. In one investigation,
both donors tested negative for WNV. In the second investigation, in which specimens for 15 of 17 donors were
available, specimens from three donors had evidence of WNV viral RNA, suggesting that these donors might have had WNV
infection at the time of donation. In addition, plasma derived from a donation by one of these three donors also had evidence of
WNV RNA. These results are preliminary because all of the specimens available for testing in both investigations were
initially processed and stored as part of routine blood collection procedures, which could affect test validity. Therefore,
additional follow-up testing and epidemiologic investigation of these donors are necessary.
In cases of suspected WNV meningitis or encephalitis in recent (e.g.,
<4 weeks before onset of illness) recipients of blood
or organs, clinicians should contact local public health authorities to initiate an investigation. Serum or tissue samples should
be retained for later studies.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of
Health and Human Services.References to non-CDC sites on the Internet are
provided as a service to MMWR readers and do not constitute or imply
endorsement of these organizations or their programs by CDC or the U.S.
Department of Health and Human Services. CDC is not responsible for the content
of pages found at these sites. URL addresses listed in MMWR were current as of
the date of publication.
Disclaimer
All MMWR HTML versions of articles are electronic conversions from ASCII text
into HTML. This conversion may have resulted in character translation or format errors in the HTML version.
Users should not rely on this HTML document, but are referred to the electronic PDF version and/or
the original MMWR paper copy for the official text, figures, and tables.
An original paper copy of this issue can be obtained from the Superintendent of Documents,
U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800.
Contact GPO for current prices.
**Questions or messages regarding errors in formatting should be addressed to
mmwrq@cdc.gov.
