Dataset Information

HIV incidence in South African blood donors from 2012 to 2016: a comparison of estimation methods.

ABSTRACT:

Background

Measuring incidence is important for monitoring and maintaining the safety of the blood supply. Blood collected from repeat-donors has provided the opportunity to follow blood donors over time and has been used to estimate the incidence of viral infections. These incidence estimates have been extrapolated to first-time donors using the ratio of NAT yield cases in first-time versus repeat-donors. We describe a model to estimate incidence in first-time donors using the limiting antigen (LAg) avidity assay and compare its results with those from established models.

Methods

HIV-positive first-time donations were tested for recency using the LAg assay. Three models were compared; incidence estimated for (1) first-time donors using LAg avidity, (2) first-time and repeat-donors separately using the NAT yield window period (WP) model and (3) repeat-donors using the incidence/WP model.

Results

HIV incidence in first-time donors was estimated at 3·32 (CI 3·11, 3·55) and 3·81 (CI 3·07, 4·73) per 1000 PY using the LAg assay and NAT yield WP models, respectively. Incidence in repeat-donors was between 2·0- and 2·5-fold lower than in first-time donors estimated at 1·56 (CI 1·37, 1·77) and 1·94 (CI 1·86-2·01) per 1000 PY using the NAT yield/WP and incidence/WP models, respectively.

Conclusion

Testing HIV-positive donations using the LAg assay provides a reliable method to estimate incidence in first-time donors for countries that collect the majority of blood from first-time donors and do not screen with NAT.

SUBMITTER: Vermeulen M

PROVIDER: S-EPMC7970713 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Publications

HIV incidence in South African blood donors from 2012 to 2016: a comparison of estimation methods.

Vermeulen Marion M Chowdhury Dhuly D Swanevelder Ronel R Grebe Eduard E Brambilla Donald D Jentsch Ute U Busch Michael M Van Zyl Gert G Murphy Edward L EL

Vox sanguinis 20200806 1

<h4>Background</h4>Measuring incidence is important for monitoring and maintaining the safety of the blood supply. Blood collected from repeat-donors has provided the opportunity to follow blood donors over time and has been used to estimate the incidence of viral infections. These incidence estimates have been extrapolated to first-time donors using the ratio of NAT yield cases in first-time versus repeat-donors. We describe a model to estimate incidence in first-time donors using the limiting ...[more]

PMID: 32762088

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Dataset Information

HIV incidence in South African blood donors from 2012 to 2016: a comparison of estimation methods.

Background

Methods

Results

Conclusion

Publications

HIV incidence in South African blood donors from 2012 to 2016: a comparison of estimation methods.

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