How long does immunity last after a COVID-19 infection?
In this article we will discuss how long immunity lasts after COVID-19 infection.
The answer is, for 90%, over 5 months. This does not guarantee protection against re-infection but it will help protect you.
How do we know this? The question was addressed by Dan et al in Science in 2021.
Immune memory against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) helps to determine protection against reinfection, disease risk, and vaccine efficacy.
Using 188 human cases across the range of severity of COVID-19, the authors analysed cross-sectional data describing the dynamics of SARS-CoV-2 memory B cells, CD8+ T cells, and CD4+ T cells for more than 6 months after infection.
They found immune memory in all three immunological components remained measurable in greater than 90% of subjects for more than 5 months after infection.
They concluded,
despite the heterogeneity of immune responses, these results show that durable immunity against secondary COVID-19 disease is a possibility for most individuals.”
Later data
According to UK parliament information, a systematic review of 12 million people found that immunological memory for SARS-CoV-2 was evident within 90% of those infected after 6-8 months. Prevalence of antibodies (90.4% of population), B memory cells (80.6% of population), and T helper cells (91.7% of population) was high.
Summary
We have explained how long does immunity lasts after COVID-19 infection. We hope you have found this helpful.
