The durability of immunity against reinfection with SARS-CoV-2: an evolutionary comparative study

Evidence before this study

We searched PubMed and Google Scholar for articles containing information on antibody levels after recovery from infection with the coronaviruses SARS-CoV-2, SARS-CoV, MERS-CoV, human coronavirus (HCoV) -OC43, HCoV-HKU1, HCoV-NL63, and HCoV-229E, and corresponding reinfection times. We have applied no language restrictions and included articles published since the inception of the database until June 30, 2021. Full details of the research are described in the methods. We have found one or more studies on each of these viral species providing data on the decrease in IgG antibodies against spike protein, core protein or whole virus lysate after infection. Additionally, one study provided re-infection time distributions for coronaviruses. However, no studies have provided estimates of the typical time to reinfection for SARS-CoV-2, SARS-CoV, or MERS-CoV.

We then searched PubMed and Google Scholar using the terms “phylogeny,” “phylogenetics,” “ancestral state estimation,” “evolution”, and “phylogenomics” in conjunction with our previous search terms. articles containing information on the phylogenetic relatedness of these coronaviruses, published since the creation of the database until June 30, 2021. No language restriction has been applied to this search. We have found extensive sequence data on these species and well-resolved phylogenies of their relationships. However, no analysis has explicitly used the resolved phylogenetic relationships to make a rigorous estimate of the durability of immunity against reinfection with SARS-CoV-2.

Added value of this study

We provide the first estimates of the expected probability of infection given the levels of IgG antibodies against the spike protein for SARS-CoV-2, as well as for SARS-CoV, MERS-CoV and the endemic coronaviruses HCoV -229E, HCoV-HKU1, HCoV-OC43 and HCoV-NL63, under endemic conditions. Characterizing the typical decline profile over time for IgG antibody levels against spike protein, core protein, and whole viral lysate, we derive the corresponding probabilities of reinfection with SARS-CoV-2 which provide a critical timeframe for many aspects of public health decision making.

Implications of all available evidence

Reports of possible reinfection with SARS-CoV-2 are increasing, but they have not reached proportions in well-monitored cohorts that would allow a quantitative epidemiological study. As a pioneering estimate, our results are consistent with increasing reports of possible reinfection with SARS-CoV-2, and indicate that reinfection after natural recovery from COVID-19 will become increasingly common as the pandemic continues. is progressing.