Are COVID vaccines less effective in people with low-immunity?

Yes, the COVID vaccines struggle to boost the immunity against COVID in people who have a defective or suppressed immune system.

A recent study published in BMJ looked at all relevant publications and confirms this. Cancer patients and patients who have received organ transplants are at risk of inadequate protection from the vaccines.

It is important that people who have low immunity get boosters as recommended by the guidelines ( third or fourth dose).


BMJ. Efficacy of covid-19 vaccines in immunocompromised patients: systematic review and meta-analysis
BMJ 2022; 376 doi: (Published 02 March 2022)
Cite this as: BMJ 2022;376:e068632

U.K. govt. COVID-19 vaccination: a guide to booster vaccination for individuals aged 18 years and over and those aged 16 years and over who are at risk. Updated 2 February 2022.

NHS. Coronavirus (COVID-19) vaccine for people with a severely weakened immune system. Page last reviewed: 24 February 2022

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