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How can contaminated donor blood transmit an infection during a blood transfusion?
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infectious disease
Birds are the primary reservoirs of West Nile virus. The virus is transmitted to humans and horses by mosquitoes that have bitten infected birds.
Contaminated donor blood can transmit infections during a blood transfusion when the blood contains pathogens—such as viruses or bacteria—that are introduced directly into the recipient's circulatory system.12
Transmission typically occurs if the donor blood has not been properly screened for infectious agents. Key mechanisms include:2
- Viral Transmission: Viruses like HIV, hepatitis B, and hepatitis C can be present in a donor's blood. Some viruses, such as cytomegalovirus and HTLV-I/II, are harbored within white blood cells, making them transmissible through cellular blood components.1
- Bacterial Contamination: This is a risk particularly for platelet components, which are stored at room temperature, potentially allowing bacteria to proliferate.1
To ensure patient safety, modern medical practice relies on rigorous screening for pathogens, including testing for antibodies, viral antigens, and nucleic acids via PCR technology, alongside procedures like leukoreduction to remove white blood cells.13