Fourth dose of COVID vaccine increases protection against severe disease and death in aged care

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Compared to only 3 doses, a fourth dose of the Pfizer vaccine gave aged care residents good extra protection against hospitalisation and death from the Omicron wave, but only moderate protection against infection, according to data out of Israel. The study found that following a 4th dose, 17.6% of residents contracted COVID compared to 24.9% in the group who only had 3 doses.  However when it came to hospitalisations, the number of people hospitalised in the 4 dose group was less than half that of the three dose group - suggesting the extra dose provided over 60 per cent protection. There were also less than half of the number of COVID deaths in the 4th dose group than in the group with only 3 doses. 

Journal/conference: JAMA Internal Medicine

Link to research (DOI): 10.1001/jamainternmed.2022.2658

Organisation/s: Tel Aviv University, Israel

Funder: Dr Dagan reported grants from Pfizer, MSD, and MedImmune-AstraZeneca as well as personal fees from Pfizer, MSD, Sanofi Pasteur, and GlaxoSmithKline outside the submitted work. No other disclosures were reported.


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