From the Guidelines
The most common microbial agent transmitted by blood transfusion is Cytomegalovirus (CMV). CMV is a herpesvirus that infects a large percentage of the general population, often without symptoms, and remains latent in white blood cells after initial infection. During blood transfusions, these infected white blood cells can be transferred to recipients. CMV is particularly concerning for immunocompromised patients, pregnant women, and premature infants who may develop serious complications if infected. Blood banks typically screen for CMV and provide "CMV-negative" blood products for high-risk recipients. While HIV, hepatitis B, and hepatitis C are serious concerns in transfusion medicine and receive significant attention in screening protocols, CMV remains more prevalent in donated blood. Modern blood screening has significantly reduced transmission rates of all these pathogens, but CMV's high prevalence in the general population makes it the most commonly transmitted microbial agent through blood transfusions 1.
Some key points to consider:
- The risk of transmitting hepatitis B and C through blood transfusion has been significantly reduced due to screening protocols, with the current incidence of post-transfusion hepatitis B estimated to be around 0.002%/transfusion recipient 1.
- The use of anti-HCV-negative organ and tissue donors has virtually eliminated the risk of HCV transmission from transplantation 1.
- Injecting-drug use is currently the primary mode of HCV transmission, accounting for 60% of HCV transmission in the United States 1.
- Despite the reduced risk of transmission, it is essential to continue screening blood donors for various infectious agents to minimize the risk of transfusion-transmitted infections.
In terms of morbidity, mortality, and quality of life, it is crucial to prioritize the prevention of CMV transmission through blood transfusions, particularly for high-risk recipients. This can be achieved through the use of "CMV-negative" blood products and strict screening protocols for blood donors. By minimizing the risk of CMV transmission, healthcare providers can significantly improve the outcomes and quality of life for patients receiving blood transfusions.
From the Research
Transfusion-Transmitted Infections
The most common microbial agents transmitted by blood transfusion include:
- Hepatitis B virus (HBV)
- Hepatitis C virus (HCV)
- Human immunodeficiency virus (HIV)
- Cytomegalovirus (CMV)
Prevalence of Transfusion-Transmitted Infections
According to studies 2, 3, 4, HBV, HCV, and HIV are among the most common transfusion-transmitted infections.
- HBV is a major risk of transfusion-transmitted infection due to the pre-seroconversion window period, infection with immunovariant viruses, and occult carriage of HBV infection 5.
- HCV and HIV are also significant risks, but the implementation of nucleic acid-amplification technology (NAT) screening has reduced the residual risk of infectious-window-period donations 3.
Comparison of Options
Comparing the options provided:
- (a) Cytomegalovirus: while CMV can be transmitted through blood transfusion, it is not the most common agent 2, 4.
- (b) Human immunodeficiency virus: HIV is a significant risk, but not the most common agent 2, 3, 4.
- (c) Hepatitis C virus: HCV is a common agent, but not the most prevalent 2, 3, 4.
- (d) Hepatitis B virus: HBV is a major risk of transfusion-transmitted infection and is considered one of the most common agents 2, 3, 4, 6, 5.