Plain language summaries of research

This is a plain language summary of an original research article. The views expressed are those of the author(s) and reviewer(s) at the time of publication.

The issue: how well do COVID-19 vaccines work in people with weak immune systems?

The MELODY Study was a research project in the UK that looked at how well COVID-19 vaccines worked in people who have weak immune systems. It is important because these people might get sick more easily and need special care. The study wanted to see if getting vaccinated helped people stay healthy, especially during a time when a new version of the virus called Omicron was going around.

What happened?

Between December 2021 and June 2022, researchers recruited 21,155 people from across the UK who had solid organ transplants (such as kidney or liver), rare autoimmune rheumatic diseases (such as vasculitis, lupus, scleroderma or myositis), or lymphoid blood cancers.

• All participants had been vaccinated for COVID-19 at least three times.
• People who took part in the study tested themselves at home for COVID 19 antibodies using a simple finger-prick test.
• They also filled out a questionnaire about their background and health.
• They were monitored for six months using NHS England data.

 

What did they find out?

Antibodies

Most people in the study did have antibodies:

• About 77% of organ transplant patients
• 85.9% of those with autoimmune diseases, and
• 79.3% of those with blood cancers.

However, about 1 in 5 people did not have these antibodies, which made them more at risk.

Infections

About 3,907 people caught COVID-19 during the study, and a smaller number (556) needed to go to hospital and sadly 20 died within 28 days of infection.

The researchers found that people with antibodies were less likely to catch COVID-19 or end up in the hospital compared to those who didn't have antibodies:

• For organ transplant patients: having antibodies lowered their chance of catching the virus by 31%  and lowered their chance of being admitted to hospital by 60%
• For those with autoimmune diseases: having antibodies lowered their chance of catching the virus 43% and lowered their chance of being admitted to hospital by 68%
• For people with blood cancer: having antibodies lowered their chance of catching the virus by 38% and lowered their chance of being admitted to hospital by 59%

 

What does this mean?

The study showed that having COVID-19 antibodies helps protect people with weak immune systems from getting ill and going to the hospital. Because the antibodies can fade over time, the researchers recommend that these people keep getting vaccinated to stay safe.

Why is this important?

Understanding how well the vaccines work can help doctors and governments make better decisions and create plans to keep vulnerable people safe. Getting vaccinated and having antibodies will protect people from COVID-19. It is particularly important to keep getting vaccinated if you have a weakened immune system.

Read the full article

---

Funding 

This study was funded by UK Research and Innovation, Kidney Research UK, Blood Cancer UK, Vasculitis UK and the Cystic Fibrosis Trust. We would like to thank them for their support. We would also like to thank all the participants in this study. 

The original article

This is a summary of: Mumford, Lisa et al. Impact of SARS-CoV-2 Spike Antibody Positivity on Infection and Hospitalisation Rates in Immunosuppressed Populations during the Omicron Period: the MELODY study. The Lancet, Volume 405, Issue 10475, 314 - 328 (available at: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)02560-1/fulltext).

This summary has been approved by a member of the research team.