Estimation of S (Spike) antibodies against CoVID-19 among vaccinated and Post infected Healthcare Workers in Selected Hospitals, in Khartoum State.

Abstract

Abstract Background: Severe acute respiratory syndrome coronavirus-2 (SARS-COv-2) which causes the coronavirus disease 2019 (COVID-19) that became a global pandemic and public health crisis, during COVID-19 pandemic, the absence of immunity in the population left them susceptible to infection with SARS-CoV-2 and healthcare workers (HCWs) being in the highest risk group. Aim: To quantify the antibody titer against COVID19 in vaccinated and un-vaccinated Healthcare Workers in selected hospitals in Khartoum state. Methods: This study was a cross-sectional study conducted in Khartoum state. During the period from June to November 2022. A list of the healthcare workers were chosen randomly by simple random sampling technique and 02 of healthcare workers (HCWS) was un-vaccinated and 70 HCWS was vaccinated group. ELISA technique was used to detect the immunoglobulin G for vaccinated and not vaccinated group collected data were competent and analyzed by using the application SPSS version 25. Results: The positive rate of anti-S antibodies after vaccination and post infection was 100%. Prevalence of antibody was higher in males than in females in post infected group only P.value (0.305) and (0.873) in post infected and vaccinated groups respectively. The highest titer level was seen in age group (43 – 54) years among vaccinated and un-vaccinated HCWS. The mean titer of anti-RBD IgG levels was insignificantly diverse among different types of vaccines. (P.value= 0.247) The highest titers of antibody was in vaccinated groups (mean 56.5) at duration (>=3 Month) more than post infected groups (mean 34.6), but there was no significant differences. The mean of antibodies titer was insignificantly different among workers occupied at the departments serving COVID‐19 patients than among those working in other departments. (P.value=.940) & (P value= 0.226) on post infected and vaccinated groups respectively. Conclusion: Seropositivity was higher among males than females and that a relatively high frequency of humoral immunity was produced in HCWs aged (43 – 54) after vaccination and post infection. Antibody titers after vaccination and post infection independently of age or gender. Antibodies against SARS-CoV-Were maintained for at least 12 months after infection and vaccination. Vaccination has positive impact on volunteers who received Jonshon and XII AstraZeneca anti-coronavirus vaccine. Since there was no significant difference between the mean of IgG titers and types of vaccine, it is less likely that there no any effect of booster’s dose and seroconversion rate or titer measured in the serum of HCWs Finally according to occupational the study showed that there was insignificant differences between IgG titers and the contact among post infected and vaccinated groups.