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.

Object To study the variation of total flavonoids in Erigeron breviscapus (Vant.) Hand.-Mazz. with the development periods, the months, the affection of the environment and genetical factors on the total flavonoids. Methods The total flavonoids in organs of E. breviscapus during the different deve-lopment periods and the months were determined. The total flavonoids of E. breviscapus in the sunny and shady habitats and the total flavonoids of E. breviscapus with different colors were compared. Results The total flavonoids of E. breviscapus mainly existed in the ground part. The total flavonoids of E. breviscapus are the highest in its flourishing period, and the lowest in its withering period. The variety of the total flavonoids in every organs of E. breviscapus in flourishing period from April to June was not significant. Illumination intensity had little affection to the total flavonoids of E. breviscapus. The colors of E. breviscapus flowers could not be the selected markers for the total flavonoids. The genetic factor played an important role in deciding the difference of the total flavonoids among the individuals. Conclusion It will be optimistic to improve the total flavonoids in E. breviscapus by genetic breeding.