Booster Cuts COVID-19-Related Mortality in Adults With Chronic Conditions

MONDAY, Jan. 30, 2023 (HealthDay News) -- For adults with two or more chronic conditions, booster vaccination with BNT162b2 or CoronaVac is associated with reductions in COVID-19-related mortality compared with two doses, according to a study published online Jan. 30 in CMAJ, the journal of the Canadian Medical Association.

Francisco Tsz Tsun Lai, Ph.D., from the University of Hong Kong, and colleagues conducted a retrospective cohort study comparing death related to COVID-19 among people aged 18 years or older with two or more chronic conditions who received a homologous booster (third) dose versus those receiving only two doses between Nov. 11, 2021, and March 31, 2022. Data were included for 120,724 BNT162b2 recipients (87,289 received a booster) and 127,318 CoronaVac recipients (94,977 received a booster).

The researchers found that among BNT162b2 recipients, there were fewer COVID-19-related deaths among those who had received a booster versus those who had received two doses (five versus 34; incidence rate, 1.3 versus 23.4 per million person-days; weighted incidence rate ratio, 0.05). Similar results were observed among those who had received CoronaVac booster vaccination versus those who had received two doses (26 versus 88; incidence rate, 5.3 versus 53.1 per million person-days; weighted incidence rate ratio, 0.08).

Our findings "highlight the potential benefit from booster vaccination, specifically in vulnerable populations living with multimorbidity, and support the recent focus on older people and those with chronic conditions for future booster doses of SARS-CoV-2 vaccines beyond the first booster," the authors write.

Several authors disclosed financial ties to pharmaceutical companies, including Pfizer.

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