Sociodemographic disparities in COVID-19 burden: changing patterns over four pandemic waves in Israel.

Background: Worldwide, the COVID-19 pandemic hit weakest populations hardest, with socioeconomic (SE), racial and ethnic disparities in COVID-19 burden. The study aimed to analyse patterns of SE and ethnic disparities in morbidity, hospitalisation, and vaccination throughout four pandemic waves.

Methods: A retrospective-archive study was conducted in Israel from 11 March 2020 to 1 December 2021, with data on confirmed cases, hospitalisations, mortality and vaccinations (three doses), obtained from the Israeli Ministry of Health's open COVID-19 database, covering 98.8% of the population, by SE and ethnic characteristics of localities.

Findings: At the outbreak of the pandemic, there was a higher caseload in Jewish, compared with Arab localities. In the second and third waves, low SE and Arab minority populations suffered 2-3 times higher morbidity, with a similar but attenuated pattern in the fourth wave. A similar trend was observed in hospitalisation of confirmed patients. COVID-19-associated mortality did not demonstrate a clear SE gradient.A strong social gradient in vaccine uptake was demonstrated throughout the period, with 71% and 74% double vaccinated in the two highest SE clusters, and 43% and 27% in the two lowest clusters by December 2021. Uptake of the third dose was 57%-60% in the highest SE clusters and 31%-25% in the lowest clusters. SE disparities in vaccine uptake were larger among the younger age groups and gradually increased from first to third doses.

Conclusions: Israel was among the first to lead a rapid vaccination drive, as well as to experience a fourth wave fuelled by diminishing immunity and the delta variant. SE and ethnic disparities were evident throughout most of the pandemic months, though less so for mortality. Despite higher COVID-19 burden, vaccine uptake was lower in disadvantaged groups, with greater disparities in the younger population which widened with subsequent doses.