Characterization of IgG Antibody Response against SARS-CoV-2 (COVID-19) in the Cypriot Population

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has hit its second year and continues to damage lives and livelihoods across the globe. There continues to be a global effort to present serological data on SARS-CoV-2 antibodies in different individuals. As such, this study aimed to characterize the seroprevalence of SARS-CoV-2 antibodies in the Cypriot population for the first time since the pandemic started. Our results show that a majority of people infected with SARS-CoV-2 developed IgG antibodies against the virus, whether anti-NP, anti-S1RBD, or both, at least 20 days after their infection. Additionally, the percentage of people with at least one antibody against SARS-CoV-2 in the group of volunteers deemed SARS-CoV-2 negative via RT-PCR or who remain untested/undetermined (14.43%) is comparable to other reported percentages worldwide, ranging anywhere from 0.2% to 24%. We postulate that these percentages reflect the underreporting of true infections in the population, and also show the steady increase of herd immunity. Additionally, we showed a significantly marked decrease in anti-NP IgG antibodies in contrast to relatively stable levels of anti-S1RBD IgG antibodies in previously infected individuals across time.

Seroprevalence of immunoglobulin G antibodies against SARS-CoV-2 in Cyprus

“…To the best of our knowledge, this is the first SARS-CoV-2 seroprevalence study carried out in Cyprus. The only other studies conducted in the Cypriot population examined the percentage of infected individuals in Cyprus who were able to produce antibodies against SARS-CoV-2 as well as the progression of SARS-CoV-2 antibody levels in SARS-CoV-2-infected individuals across time as a means of monitoring their antibody-mediated immunity after SARS-CoV-2 natural infection [ 25 , 26 ].…”

Recapping the Features of SARS-CoV-2 and Its Main Variants: Status and Future Paths

“…Seroprevalence studies indicate many infected people develop anti-S and anti-N antibodies, but titers change differently across time. It seems that in either vaccination or infection, both kind of antibodies are produced, but only anti-S (S-IgA and S-IgG) are maintained, and anti-N soon disappear (N-IgA and N-IgG) [ 42 , 43 ]. In this sense, a remanent question has been whether testing for antibodies provides useful information or not.…”