The study investigates SARS-CoV-2 seroprevalence among vaccinated hospital workers

Recent studies posted on medRxiv* The preprint server measured the humoral response of vaccinated hospital personnel to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2).

Background

The 2019 Coronavirus Disease (COVID-19) pandemic has been a global health crisis for two years, causing more than 456 million infections and more than 6 million deaths. Researchers have extensively studied pandemics and their pathogen, SARS-CoV-2, to understand their pathogenic mechanisms and to comprehensively develop treatments. Several studies have been conducted to determine the seroprevalence of SARS-CoV-2 in the general population. Therefore, researchers in the current study have been positively assessing the seroprevalence of workers at the University Medical Center Hamburg-Eppendorf since the beginning of the pandemic.

Since the report of thromboembolism among AstraZeneca AZD1222 (Vaxzevria) vaccine recipients, it has been discontinued in Germany since March 2021 for people under the age of 60. This change resulted in a heterologous primary vaccination, with the second vaccination being either the Pfizer BNT162b2 or the Moderna mRNA-1273 vaccine.

After the massive explosion of COVID-19 infection in the fall of 2021, booster immune vaccines were approved for preferential administration to vulnerable populations from October 2021. The booster immunization program was expanded to the general population in December 2021.

the study

In this study, researchers conducted a seroprevalence study to assess COVID-19 infection and vaccination-induced immunity among institutional health professionals. Serum samples were collected from facility employees between January 17-31, 2022, as mentioned above. COVID-19 vaccination and infection status were determined using REDcap, an online tool designed by the author to capture electronic data.

The presence of antibodies against the receptor binding domain (RBD) of the spike (S) protein was assessed using a quantitative assay (Elecsys anti-S1-RBD-SARS-CoV-2). Similarly, anti-nucleocapsid (anti-NC) antibodies were detected in the Elecsys anti-NC-SARS-CoV-2Ig assay.

result

Approximately 697 hospital staff participate in the current study, accounting for approximately 6% of the workforce of university medical centers. The median age of participants was 40, with women accounting for 78.5% of the cohort. Most participants were involved in patient care, but only 99 were not involved in patient care. All but five had received at least one dose of SARS-CoV-2. Five participants were vaccinated four times and more than 92% were vaccinated three times.

Anti-S1-RBD antibody was detected among those who received at least one vaccination at a median. titer 13,891 Arbitrary unit (AU) / ml. Anti-NC antibodies were detected in 62 people, indicating a previous COVID-19 infection. There were no anti-NC antibodies among the 5 people who received the COVID-19 vaccine four times. Previous COVID-19 infections significantly increased the anti-S1-RBD titers of vaccinated individuals. Antibody titers were higher in the heterologous vaccination group than in individuals who received three mRNA vaccinations. Immunity of individuals who received one Vaxzevria and two mRNA vaccines (AZD1222 + mRNA + mRNA vaccine) and individuals who received Vaxzevria primary vaccination (AZD1222 + AZD1222 + mRNA) and booster vaccine. There was no difference in the response. course.

Multiple linear regression analysis identified age, time elapsed from booster immunization, vaccination regimen, and the presence of antibodies against SARS-CoV-2NC as significant predictors of anti-S1-RBD titers. In particular, the presence of anti-NC antibodies and time from booster immunization were the only statistically significant factors. Analysis of the anti-S1-RBD titers of individuals inexperienced with SARS-CoV-2 at previous levels (since May 2021) revealed a significant increase in antibody titers. A similar increase in humoral response was observed in 222 of the 251 double-vaccinated during the previous visit (for serum collection) and was the third by this visit (January 2022). I was boosted by the administration of. After booster vaccination, only 26 workers had lower antibody titers compared to previous levels.

Conclusion

Researchers have observed that the prevalence of anti-NC antibody titers in January 2022 doubled the prevalence of infection from the previous assessment in May 2021. The incidence of COVID-19 was significantly lower among hospital workers than in the general population.Along with various studies, the authors reported three exposures to SARS-CoV-2. antigen High levels of antibody must be mediated by vaccine-induced immunity or hybrid immunity (infection and two vaccinations) to generate a strong humoral response. Their findings show that current infection control interventions are powerful and effective in preventing nosocomial infections.

*Important Notices

medRxiv publishes unpeer-reviewed preliminary scientific reports and should not be considered definitive, guide clinical / health-related behaviors, or be treated as established information.