From the Guidelines
The most common microbial agent transmitted by blood transfusion is hepatitis C virus (HCV), which corresponds to option (c). Despite significant improvements in blood screening procedures over the past decades, HCV remains a concern due to its ability to establish chronic infection in many carriers who may be asymptomatic and unaware of their infection status. HCV has a relatively long window period during which newly infected individuals may test negative on screening tests while still being infectious, as noted in studies such as 1. The virus primarily affects the liver and can lead to chronic hepatitis, cirrhosis, and hepatocellular carcinoma if left untreated. While HIV, hepatitis B virus, and cytomegalovirus can also be transmitted through blood transfusions, their transmission rates have been reduced more effectively through improved screening methods and donor selection criteria, as discussed in 1 and 1. Blood banks employ nucleic acid testing (NAT) to detect HCV RNA, which has significantly reduced but not completely eliminated the risk of transfusion-transmitted HCV infection. Recent guidelines, such as those from 1 and 1, highlight the importance of screening for various hepatitis viruses, including HEV, but the primary concern regarding blood transfusions remains HCV due to its prevalence and the potential for chronic infection. Key points to consider include:
- The ability of HCV to cause chronic infection
- The long window period of HCV during which individuals may be infectious but test negative
- The effectiveness of NAT in reducing but not eliminating the risk of HCV transmission
- The comparative risks of transmitting other viruses like HIV, HBV, and CMV through blood transfusion, which are lower due to improved screening and selection processes. Given the information from 1, which provides a more recent perspective on the transmission of HCV through blood transfusions, it is clear that HCV remains a significant concern. However, it's also important to note the emergence of guidelines addressing HEV, as seen in 1 and 1, which may alter the landscape of blood transfusion safety in the future. For now, HCV stands out as the most common microbial agent transmitted by blood transfusion, based on the available evidence and the ongoing challenges in completely eliminating its transmission through blood products.
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 various studies 2, 3, 4, 5, 6, HBV remains a major risk of transfusion-transmitted infection due to the pre-seroconversion window period, infection with immunovariant viruses, and occult carriage of HBV infection.
Risk of Transfusion-Transmitted Infections
The risk of transfusion-transmitted infections has been reduced significantly with advanced technologies and improved donor screening 6. However, the risk of transmission still exists, particularly for HBV, which can be transmitted even with negative serological tests and NAT results 3, 6.
Comparison of Transfusion-Transmitted Infections
While all the options (a, b, c, d) are potential transfusion-transmitted infections, the most common one is not explicitly stated in the provided studies. However, based on the information provided, it can be inferred that HBV is a significant risk due to its window period and occult carriage 3.
Key Findings
Key findings from the studies include: