This study in the British Medical Journal analyzes who is at highest risk of death even after having been vaccinated

The authors of this article use a risk prediction model to stratify risk of severe covid-19 outcomes among people that are already fully vaccinated. They found that the dominant risk factors for breakthrough hospitalization and death are people with:

  • Down syndrome
  • Kidney transplantation
  • Sickle cell disease
  • Nursing home residents
  • People undergoing chemotherapy
  • People with a recent bone marrow or solid organ transplant
  • People with HIV/AIDS, dementia, Parkinson’s disease, neurological conditions, and liver cirrhosis.

Everybody in all of these categories should get a booster shot 6 months after they were fully vaccinated.