A paper published in Nature by Arbel and others 25th April 2022 answers this question.
The rapid emergence of the Omicron variant of SARS-CoV-2 has led to a global resurgence of COVID-19 disease.
Israeli authorities approved a fourth COVID-19 vaccine dose, the second booster, for individuals aged 60 and over who had received their first booster dose four or more months earlier.
Evidence regarding the effectiveness of a second booster dose in reducing hospitalisations and mortality due to COVID-19 is essential.
The authors conducted a retrospective cohort study including all members of Clalit Health Services aged 60 to 100 years who were eligible for the second booster on January 3rd 2022.
Hospitalisations and mortality due to COVID-19 amongst participants who received the second booster were compared with participants who had received only one booster dose.
They used statistical analysis to estimate the association between the second booster and hospitalisation and death due to COVID-19 whilst adjusting for demographic factors and coexisting illnesses.
A total of 563,465 participants met the eligibility criteria.
Of those, 328,597, 58%, received a second-booster dose during the 40-day study period.
Hospitalisations due to COVID-19 occurred in 270 of the second booster recipients and in 550 participants who received only one booster dose.
Death due to COVID-19 occurred in 92 of the second booster dose recipients and in 232 participants who received one booster dose.
This study demonstrates a substantial reduction in hospitalisations and deaths due to COVID-19 conferred by a second booster dose in Israeli adults aged 60 years and over.
Dr Paul Ettlinger
BM, DRCOG, FRCGP, FRIPH, DOccMed