Zika and Blood Transfusion

What we know

• On July 6, 2018, FDA issued revised guidance recommending that blood centers in all states and U.S. territories screen donated whole blood and blood components with a blood screening nucleic acid test licensed for use by FDA. Screening could be performed by pooling samples from multiple donations but with triggering to individual donation testing when there is increased risk for local, mosquito-borne transmission of Zika virus. Alternatively, an FDA-approved pathogen-reduction device may be used for plasma and apheresis platelet donations.
• Most people infected with the Zika virus don’t show any symptoms, blood donors may not know they have been infected.
• To date, there have been no confirmed transfusion-transmission cases of Zika virus in the United States.  However, cases of Zika virus transmission through platelet transfusions have been documented in Brazil.

Zika Virus Blood Screening

• Blood donor screening on the basis of a questionnaire, without a laboratory test, is insufficient for identifying Zika-infected blood donors in areas with active mosquito-borne transmission of Zika virus due to the high rate of asymptomatic infection.
• FDA has licensed two blood donor screening tests to detect Zika virus RNA in human plasma: the cobas Zika Test performed on the cobas 6800/8800 (Roche Molecular Systems, Inc) on October 5, 2017 and the Procleix Zika Virus Assay (Grifols Diagnostic Solutions, Inc.) on July 5, 2018.
• Blood donations that test positive for Zika virus are removed from the blood supply.

For Blood Collection Centers and Health Departments

One of the most important aspects of blood safety is making sure donated blood does not cause harm. One way CDC plays an important role in keeping the blood supply safe is by assisting state and local health departments and hospitals in investigating reports of potential infectious disease transmission. CDC developed an Investigation Toolkit: Transfusion-Transmitted Infections (TTI) as a resource to facilitate investigating and tracking potential transfusion-associated cases of infection (e.g., by public health departments). The toolkit provides a broadly applicable framework for transfusion investigations.

• Investigation Toolkit: Transfusion-transmitted Infections (TTI)