Dear Editor,
We would like to share ideas on the publication “Impact of vaccination on SARS-CoV-2 seroprevalence rate in French blood donors: an assessment as of July 2021 [1].” According to Gallian et al., seroconversions (new infections and vaccinations) and the declining of titres over time, which may eventually result in seroreversion, are balanced out by anti-SARS-coV-2 antibody prevalence and titres. Seroprevalence rates and quantitative levels of SARS-CoV-2 antibodies can be monitored in blood donors to give health authorities information on the dynamics and level of immunity in the general population. We both agree that vaccination among the general population may have an impact on the seroprevalence pattern. But we must be aware of the potential impact of asymptomatic COVID-19 [2]. Many persons with COVID-19 are asymptomatic, and they typically have no prior medical history. Consequently, a specific method must be used to record this particular population.
Conflict of interest
None.
References
- 1.Gallian P., Slimani A., Malard L., Morel P., de Lamballerie X. Impact of vaccination on SARS-CoV-2 seroprevalence rate in French blood donors: An assessment as of July 2021. Transfus Clin Biol. 2022 doi: 10.1016/j.tracli.2022.08.002. Online ahead of print. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Joob B., Wiwanitkit V. Letter to the Editor: Coronavirus Disease 2019 (COVID-19), Infectivity, and the Incubation Period. J Prev Med Public Health. 2020;53(2):70. doi: 10.3961/jpmph.20.065. [DOI] [PMC free article] [PubMed] [Google Scholar]