Jerusalem's CoVID-19 Experience-The Effect of Ethnicity on Disease Prevalence and Adherence to Testing.

BACKGROUND: The management of the SARS-CoV-2 pandemic depends amongst other factors on disease prevalence in the general population. The gap between the true rate of infection and the detected rate of infection may vary, especially between sub-groups of the population. Identifying subpopulations with high rates of undetected infection can guide authorities to direct resource distribution in order to improve health equity. METHODS: A cross-sectional epidemiological survey was conducted between April and July 2021 in the Pediatric Emergency Department of the Shaare Zedek Medical Center, Jerusalem, Israel. We compared three categories: unconfirmed disease (UD), positive serology test result with no history of positive PCR; confirmed disease (CD), history of a positive PCR test result, regardless of serology test result; and no disease (ND), negative serology and no history of PCR. These categories were applied to local prevailing subpopulations: ultra-orthodox Jews (UO), National Religious Jews (NRJ), secular Jews (SJ), and Muslim Arabs (MA). RESULTS: Comparing the different subpopulations groups, MAs and UOs had the greatest rate of confirmed or unconfirmed disease. MA had the highest rate of UD and UO had the highest rate of CD. UD significantly correlated with ethnicity, with a low prevalence in NRJ and SJ. UD was also associated with larger family size and housing density defined as family size per number of rooms. CONCLUSION: This study highlights the effect of ethnicity on disease burden. These findings should serve to heighten awareness to disease burden in weaker populations and direct a suitable prevention program to each subpopulation's needs. Early awareness and possible intervention may lower morbidity and mortality.

SARS-CoV-2 antibodies started to decline just four months after COVID-19 infection in a paediatric population.

AIM: We evaluated the prevalence of paediatric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections using antibody testing and characterised antibody titres by time from exposure. METHODS: This was a single-centre, prospective, cross-sectional cohort study. Patients under 18 years old were eligible to participate if they attended the paediatric emergency department at the tertiary Shaare Zedek Medical Center, Jerusalem, Israel, from 18 October 2020 to 12 January 2021 and required blood tests or intravenous access. SARS-CoV-2 seropositivity and antibody levels were tested by a dual-assay model. RESULTS: The study comprised 1138 patients (56% male) with a mean age of 4.4 years (interquartile range 1.3-11.3). Anti-SARS-CoV-2 antibodies were found in 10% of the patients. Seropositivity increased with age and 41% of seropositive patients had no known exposure. Children under 6 years of age had higher initial antibody levels than older children, followed by a steeper decline. The seropositivity rate did not vary during the study, despite schools re-opening. The findings suggest that children's immunity may start falling 4 months after the initial infection. CONCLUSION: Immunity started falling after just 4 months, and re-opening schools did not affect infection rates. These findings could aid decisions about vaccinating paediatric populations and school closures.