Obesity reduces the protection time of the vaccine against Covid – 05/24/2023 – Equilíbrio

A study released in England pointed out that obesity accelerates the loss of immunity promoted by the vaccine against Covid-19. The researchers suggest that severely obese people probably need more frequent booster shots than people of normal weight to remain protected against the disease.

Clinical trials also pointed out that immunizers against the coronavirus remain highly effective in reducing symptoms, hospitalization and deaths, even in obese people.

Scientists at the universities of Cambridge and Edinburgh assessed data from 3.6 million Scots through the EAVE II platform (Early Pandemic Assessment and Enhanced Covid-19 Surveillance, in Portuguese). Adults who received two doses of the vaccine were considered.

The research investigated the relationship between BMI (body mass index), hospitalization and mortality from Covid-19. Individuals with severe obesity (BMI greater than 40) were 76% more likely to suffer hospitalization or death from the coronavirus even though they were vaccinated, indicating a more rapid loss of protection from immunizers.

The article was published this month in Nature and also brought data from a comparative study conducted in England with 28 individuals with severe obesity and 41 participants with normal BMI (18.5 to 24.9). The researchers analyzed the volunteers six months after the second dose of the vaccine and their response to the booster dose.

The results were significant. Even restored after the third dose, the immunization of the obese was lost earlier. One semester after the application of the vaccine, it was no longer possible to quantify neutralizing antibodies in 55% of those with severe obesity, a situation that happened in 12% of those of average weight.

During the period of action of the vaccine, the virus was also less neutralized by the vaccine in those with higher BMI. “The neutralizing capacity was restored by a third dose of vaccine, but again declined more rapidly in people with severe obesity,” state the authors.

The work does not indicate the reason for the difference, but the discovery raises important points for the creation or modification of public policies for the treatment of obesity and the fight against Covid-19. “As obesity is associated with increased hospitalization and mortality from infections, our findings have implications for policy prioritization of vaccines,” the researchers state in the paper.

The work also points out that people with obesity (BMI 30 to 39.9) and low weight (index below 18.5) may have reduced vaccine protection time.

“This study further emphasizes that obesity alters vaccine response and also affects the risk of infection. We urgently need to understand how to restore immune function and minimize these health risks,” said Agatha van der Klaauw of Wellcome-MRC in a statement. Institute of Metabolic Science, one of the authors of the paper.

Between September 14, 2020 and March 19, 2022, the period of analysis of the patients, 10,983 individuals with severe cases of Covid-19 were counted. Of these, 9,733 were hospitalized, and 2,207 died from the virus.

Pediatrician and infectologist Renato Kfouri, vice president of the SBI (Brazilian Society of Immunizations), says that obesity, especially the more severe type, is recognized as a vulnerability factor for several infectious diseases.

“The inflammatory process generated by obesity leads to a functional alteration of our immune system, which makes obese people more victims of various diseases, such as hepatitis, pneumonia, flu. And with Covid it was no different, proving to be a risk group” , says Kfouri.

The more vulnerable immune system also affects the effectiveness of some vaccines and, for the infectologist, the UK study is important for assessing this trend in Covid-19. “With hepatitis B, with the flu, this population of obese people responds worse to vaccination. The news is in relation to Covid, as these are the first studies with obese people and on the duration of protection [ao coronavírus].”

For Kfouri, despite the results, the period between doses should remain the same, prioritizing immunosuppressed patients (patients with cancer, HIV, transplants and others undergoing chemotherapy or immunosuppressive drugs).

“So, for the time being, there is no prospect of changing the vaccination schedule for obese people in that sense”, says the doctor.