Investigation of coronavirus immunity before and during the COVID-19 pandemic in Uganda

Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) causes the coronavirus disease COVID-19.

During the two years since the virus and the disease was first discovered, COVID-19 has by mid-March 2022 caused at least 480 million infections and 6.2 million deaths world-wide.

The pandemic hit unevenly across the world population, with characteristics such as age, male sex, underlying conditions, and host genetics influencing the risk of developing severe disease.

Interestingly, available data suggests that East African countries such as Uganda have been relatively less affected in terms of severe COVID-19 disease and mortality compared to many western countries, despite very limited and delayed vaccine availability.

In this proposal, we hypothesize that pre-existing T cell immunity to coronaviruses gained before the pandemic may influence these patterns of susceptibility to severe COVID-19.

To address this possibility, we will utilize the Ugandan arm of the RV329 African Cohort Study (AFRICOS), which has a retrospective longitudinal set of cryopreserved samples covering pre-pandemic and pandemic time-points.

This cohort will also allow us to address the impact of HIV-1 infection on the characteristics of pre-existing immunity.

We anticipate that the proposed experiments, together with the comprehensive clinical data collected in the AFRICOS study, will significantly enhance our understanding of the role of pre-existing T cell immunity to protect from severe COVID-19.