COVID, Vaccines and Cancer- August 2023

Malcolm Rhodes(National COVID antibody survey charity/supporters team) -Editorial

When the first COVID vaccines were tested, they were found to be remarkably effective and were rolled out around the world. However, people with cancer were not included in the trials and it was not clear how effective vaccines would be for them. It was already suspected that cancer patients would be more likely to catch COVID and that vaccines may be less effective for some of these people. 

A huge study was done to find out how effective vaccines are for cancer patients compared with the general population. The study found that after two doses, the vaccines were less effective for cancer patients. The effectiveness of the vaccines also fell over time more quickly for cancer patients. Cancer patients were more at risk of catching COVID during treatment, or up to a year after. After three vaccine doses, protection was greatly increased for most of the general population and for most cancer patients, but some were still left with little protection2. In particular, blood cancer patients often had lower protection compared with the general population. 

Blood cancer patients are at higher risk from COVID infection than (4x to 8x higher) than the general population. They are at higher risk than other cancer patients. Some cancer treatments such as Rituximab and CAR-T can contribute to this higher risk as they can suppress the immune system and reduce vaccine effectiveness. However, this risk should be weighed up against the benefits of receiving cancer treatment on a case-by-case basis.

What does this mean to patients? Well…… firstly, take some reassurance. Over time, protection levels for cancer patients have improved. That’s been the work that everyone has been doing around the country, vaccines, and potentially also the newer milder COVID-19 variants. 

However, talking to clinical lead, Lennard, he told me that it also shows that we can do more for blood cancer patients. Compared to patients with non-blood cancer, and compared to the population, the risk to blood cancer patients is still high. Along with patient charities, groups and our clinicians we all continue to call for more work to maintain this focus to drive this down further and leave no one behind. 


  1. Lee et al. (2022). Vaccine effectiveness against COVID-19 breakthrough infections in patients with cancer (UKCCEP): a population-based test negative case-control study. Lancet Oncology 23 (6), p748-757,
  2. Lee et al. (2022). COVID-19: Third dose booster vaccine effectiveness against breakthrough coronavirus infection, hospitalisations and death in patients with cancer: A population-based study. European Journal of Cancer 175, p1-10,
  3. Starkey, T., Ionescu, M.C., Tilby, M. et al. A population-scale temporal case–control evaluation of COVID-19 disease phenotype and related outcome rates in patients with cancer in England (UKCCP). Sci Rep 13, 11327 (2023).

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