Overall Incidence of HIV in Donated Blood Declined Despite Reduction in Deferral Periods

New research published in Transfusion1 shows that decreasing the deferral period for blood donation in those with high-risk behaviors, such as injection drug use and men having sex with other men, did not increase the incidence of HIV, hepatitis B (HBV), or hepatitis C (HCV) in donated blood. The incidence of these viruses in blood decreased between 2017 and 2023 and did not affect the safety of the blood supply.

The change in deferral period did not increase the incidence of infectious diseases appearing in blood donations | Image credit: New Africa - stock.adobe.com

The deferral period for individuals engaging in high-risk behavior was decreased from 12 months to 3 months in 2020 amid blood shortages due to the pandemic.2 Blood is assessed for infection before its use in hospitals for the safety of the patient, with approximately 60% of donations being assessed through the Transfusion-Transmissible Infections Monitoring System that is funded by the FDA. This study used the monitoring system to assess the incidence of HIV, HBV, and HCV in repeat blood donors in both the 12-month and 3-month deferral periods, as well as to estimate the first-time and overall donor incidence of infection during these periods.

Data were collected starting on September 1, 2015, with data from May 15, 2017, to September 19, 2023, used for the analysis. The data were split into 2 groups based on the deferral period, from May 15, 2017, to May 15, 2020, for the 12-month group, and from May 15, 2020, to September 18, 2023, for the 3-month group. Demographics for the donors were self-reported. The ages of the donors were divided into groups of 16 to 17 years, 18 to 24 years, 25 to 54 years, and 55 years and over.

Repeat donor incidence for those who made at least 2 donations during the period was estimated. First-time donor incidence was estimated by using the rate of nucleic acid testing-confirmed but seronegative yield expressed as a ratio and multiplied by repeat donor incidence. Proportional, period-specific first-time and repeat incidence were combined to calculate the weighted overall incidence.

There were 43,217,459 donations that were included in the study, of which 20,158,042 were from the 12-month period and 23,059,417 were from the 3-month period. There were 15,981,979 donations in the 12-month period and 19,496,095 donations in the 3-month period that were from repeat donors. Women made up 50.3% of the 12-month group and 53.4% of those in the 3-month group. Most of the blood came from those aged 25 to 54 years in both groups (46.3% in 12 months, 46.6% in 3 months).

The 12-month deferral period saw an incidence rate of 1.2 per hundred thousand person-years in HIV incidence, which decreased to 0.8 in the 3-month period. Donors who were identified as Black, aged 18 to 24 years, and male had the highest decrease in HIV incidence.

The incidence of HBV remained stable from the 12-month to 3-month period (0.78 vs 0.8). There were no significant differences in the rates of HBV in different demographics. The incidence of HCV decreased from 1.7 per hundred thousand person-years with a 12-month deferral to 0.4 for a 3-month deferral.

Window-period residual risk decreased in HIV from 1 per 3.3 million during the 12-month deferral period to 1 per 5.0 million donations in the 3-month period. Window-period residual risk decreased slightly in HBV from 1 per 2.6 million donations during the 12-month period to 1 per 2.5 million donations during the 3-month period. All rates of HCV declined, with the highest change for repeat donors from 1 per 2.9 million donations to 1 per 12 million donations for the 12-month and 3-month periods, respectively.

There were some limitations to this study. Negative donors could return and contribute to both periods and were included in both the 3-month and 12-month deferral times databases. External factors could not be adjusted for due to the need for multiple years of data.

“In conclusion, data from approximately 60% of the US blood supply between May 2017 and September 2023 demonstrated that, despite some fluctuations in rates for certain subgroups, HIV, HBV, and HCV incidence and [window-period residual risk] did not increase and, in fact, decreased,” the authors concluded.

The authors noted that the safety of blood supply should continue to be monitored going forward to maintain the low incidence rates.

References

1. Huseynova E, Haynes J, Notari EP, et al. Incidence and window period residual risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus in United States blood donations, 2017 to 2023: the transfusion-transmissible infections monitoring system. Transfusion. Published online September 7, 2025. doi:10.1111/trf.18938

2. Harmon GE. The FDA must lift its discriminatory blood-donor policy. January 26, 2022. Accessed September 8, 2025. https://www.ama-assn.org/about/leadership/fda-must-lift-its-discriminatory-blood-donor-policy