Hepatitis E is an acute and self-limiting viral hepatitis caused by the hepatitis E virus (HEV). It has a higher mortality rate among immunosuppressed patients and pregnant women infected with HEV. Although HEV infections in humans are mostly caused by contaminated water or food worldwide, the incidence of transfusion-transmitted hepatitis E is continuously rising. Additionally, the prevalence of serum anti-HEV IgG in the blood donors in China is at a relatively high level, making it worth considering screening blood donors for HEV. This article briefly reviews the globally reported cases of transfusion-transmitted hepatitis E and the HEV screening strategies for blood donations.

[Objective] To conduct a retrospective statistical comparison of alanine aminotransferase (ALT) test values in blood donors prior to blood collection, aiming to analyze the objective characteristics of the population with elevated ALT levels (ALT>50 U/L) and provide reference data for adjusting the screening eligibility threshold for ALT. [Methods] The preliminary ALT screening data of 30 341 blood donor samples collected prior to blood donation from three smart blood donation sites at the Shenzhen Blood Center between 2022 and 2023 were extracted and compared with data from a health examination department of a tertiary hospital in Shenzhen (representing the general population, n=24 906). Both datasets were categorized and statistically described. A retrospective analysis was conducted to examine the associations between ALT test results and factors such as donors' gender, age, ethnicity, donation site, donation season, and frequency of blood donation. [Results] The ALT levels in both blood donors and the general population were non-normally distributed. The 95th percentile of ALT values was calculated as 61.4 U/L (male: 67.8 U/L, female: 39.3 U/L) for blood donors and 58.1 U/L (male: 63.7 U/L, female: 51.2 U/L) for the general population. The non-compliance rates (ALT>50 U/L) were 7.65% (2 321/30 341) in blood donors and 7.08% (1 763/24 906) in the general population. There were significant differences (P<0.05) in the ALT failure rate among blood donors based on gender, age, and donation site, but no significant differences (P>0.05) during the blood donation season. There was no statistically significant difference (P>0.05) in the positive rates of four serological markers (HBsAg, anti HCV, HIV Ag/Ab, anti TP) for blood screening pathogens between ALT unqualified and qualified individuals (2.05% vs 1.5%). If the ALT qualification threshold was raised from 50 U/L to 90 U/L, the non qualification rates of male and female blood donors would decrease from 9.82% (2 074/21 125) to 2.23% (471/21 125) and from 2.70% (249/9 216) to 0.75% (69/9 216), respectively. Among the 154 blood donors who donated blood more than 3 times, 88.31% of the 248 ALT test results were in the range of 50-90 U/L. Among them, 9 cases had ALT>130 U/L, and ALT was converted to qualified in subsequent blood donations. [Conclusion] There are differences in the ALT failure rate among blood donors of different genders and ages, and different blood donation sites and operators can also affect the ALT detection values of blood donors. The vast majority of blood donors with ALT failure are caused by transient and non pathological factors. With the widespread use of blood virus nucleic acid testing, appropriately increasing the ALT qualification threshold for blood donors can expand the qualified population and alleviate the shortage of blood sources, and the risk of blood safety will not increase.

[Objective] To investigate the factors associated with alanine aminotransferase (ALT) abnormalities in multi-ethnic blood donors across five Zang autonomous prefectures in the plateau regions of Qinghai Province, and to provide evidence for ensuring blood safety and formulating screening strategies. [Methods] A retrospective analysis was performed on the ALT abnormal test results of blood donors in the Zang autonomous prefectures of Qinghai from 2022 to 2024. The correlations between ALT levels and factors including gender, age, altitude, and infectious markers were investigated. [Results] The overall ALT unqualified rate among blood donors in this region was 9.01%. Significant differences in ALT levels were observed across genders and age groups (P<0.05). Variations in ALT abnormality rates were also noted among different plateau regions (P<0.05). Overall, ALT values exhibited an increasing trend with rising altitude. The average ALT unqualified rates were 11.19% in Zang donors, 7.96% in Han donors, and 4.79% in donors from other ethnic groups (P<0.05). No statistically significant association was observed between ALT abnormality and the presence of HBV/HCV infectious markers (P>0.05). [Conclusion] In the plateau areas of Qinghai, multi-ethnic blood donors have a relatively high ALT levels and ALT unqualified rates, showing distinct regional characteristics. ALT elevation in voluntary blood donors is related to non-pathological factors such as gender, age, and dietary habits, but not to infectious indicators.

Chemiluminescence immunoassay (CLIA), a non-radioactive immunoassay technology that has developed rapidly over the past three decades, has increasingly demonstrated its application value in blood screening due to its advantages such as high sensitivity, high specificity, rapid detection, and high degree of automation. This article systematically reviews the application status, technical characteristics, differences from traditional methods, influencing factors for promotion and application of CLIA in blood screening at home and abroad, and looks forward to its development prospects. Countries such as the United States, Germany, and Japan have widely adopted CLIA in the screening of pathogens like HBV, HCV, and HIV, predominantly using "1 CLIA test + 1 nucleic acid testing (NAT) test" model. Some regions have also expanded testing items to include anti-HBc and HTLV. In China, enzyme-linked immunosorbent assay (ELISA) combined with NAT remains the primary method. CLIA is still in the stage of detection performance comparison. However, domestic reagents have gradually been approved, and more enterprises are accelerating their layout in this field. CLIA is superior to ELISA in terms of sensitivity, detection range, and automation adaptability, which can reduce missed detection and shorten the window period. But it is limited by factors such as high cost, closed system characteristics, and domestic batch release supervision. In the future, CLIA is expected to complement existing technologies, expand the detection of emerging and re-emerging pathogens, and combine with fully automated assembly lines to improve screening quality, providing more comprehensive protection for clinical blood transfusion safety.

Objective: To retrospectively analyze the prevalence of hepatitis C virus (HCV) infection among voluntary blood donors in Qinghai Province over a ten-year period and to provide evidence for refining blood safety screening strategies. Methods: Blood samples from 362 066 blood donors in Qinghai collected between January 2015 and April 2024 were simultaneously screened using enzyme-linked immunosorbent assay (ELISA) and nucleic acid testing (NAT). Follow-up was conducted for donors with reactive HCV RNA screening results, and alanine transaminase (ALT) was detected by rate method. Results: The HCV positive rate among blood donors in Qinghai was 0.22%. Gender, marital status, number of blood donations, and educational level were associated with HCV infection. Significant differences in HCV positive rates were observed among donors across regions and ethnic groups. The HCV positive rate among donors in Golog Tibetan Autonomous Prefecture (with an average altitude of 4 330 m) was significantly higher than that in Xining (0.52% vs 0.21%, P<0.001). Positivity rates were also significantly higher in Salar (0.84%), Hui (0.81%), Zang (0.60%), and Tu (0.45%) ethnic groups compared to the Han ethnic group (0.17%) (P<0.001). The abnormal rate of ALT in HCV-positive donors was higher than in non-HCV donors (6.13% vs 1.55%) (P<0.001). Conclusion: The relatively high HCV positivity rate among blood donors in Qinghai highlights the need for further investigation into viral sources, risk factors, and transmission routes. Optimized screening strategies are essential to ensure blood safety.