Abstract
Background and Objectives: The decline in HIV prevalence and availability of nucleic acid testing to reduce the window period for HIV infection have allowed men who have sex with men (MSM) to donate blood in many countries, based on research evidences which support their blood safety. To assess the situation in Thailand, this study was conducted to assess the risk of blood-borne transmission from Thai MSM compared to male donors as a control group. Material and methods: This is a prospective cohort study, recruiting MSM nationwide from the Thai national blood centre (NBC), and 9 regional blood centres between 15 March and 15 September 2023. Calculated sample size is 159 for each group. MSM who has a partner were included and MSM who uses PrEP/PEP are excluded from the study. MSM who has only one partner and not exposed to sex worker or illicit drug was classified as low-risk, while MSM with more than one partner or has other sexual risk behaviors was classified as high-risk. Eligible participants have blood sampling to test for transfusion-transmitted infection (TTI): HIV, HBV, HCV, and Syphilis, twice, 3 months apart. The low-risk MSM were to refrain from having sex in the 3-month study period. The infection pressure of TTI were compared with the control age-matched male donors using two proportion Z-test with level of significance (α) at 0.05. Results: Of 192 MSM aged 19-26 years who were recruited for the study, 73 were eligible, 32 were low-risk and 41 were high-risk. Blood tests were positive for TTI in 3 participants, 2 in the high-risk group (Syphilis and HBV), and 1 in the low-risk group (Syphilis), and there were no TTI in matched regular donor controls. The calculated % infection pressure in the high-risk group is significantly higher than controls (4.88% vs. 0.00%, p-value=0.0285). The low-risk group has little difference in infection pressure to the high-risk group (3.12% vs. 4.88%) and the statistical significance couldn’t be demonstrated. The MSM participants also have significant higher % infection pressure compared with general Thai male donors (4.10% vs. 0.95%, p-value=0.0028), with 3.28 times higher in the low-risk group (clinical significance). There was no increase in TTI on the 3-month follow-up blood test. Discussion and conclusion: There were much lower participants than anticipated (73/318). This could be due to the exclusion of MSM who use PrEP, and cultural sensitivity to the the study criteria. Despite the limited number of participants, it can be concluded that Thai people with MSM continue to be a clinically significant risk group for transfusion-related infection. There is no strong evidence to support the change of criteria for deferral of Thai MSM donors at this time. Further study is needed to ensure patient blood safety.
