Older adults have an increased risk of COVID-19, so it is essential that vaccines against the disease are effective in this age group.
“Immune responses to vaccines are often diminished in the elderly because the immune system gradually deteriorates with age, which also makes the elderly more vulnerable to infections,” said study author and professor. in Oxford, Andrew Pollard.
“As a result, it is crucial that COVID-19 vaccines are tested in this group which is also a priority group for vaccination,” he said in a press release from The Lancet.
The phase 2 trial of the ChAdOx1 nCoV-19 vaccine included 560 healthy adults, of whom 240 were over 70 years of age.
He found that the vaccine caused few side effects, was better tolerated in older adults than in young adults and produced a similar immune response in all age groups.
Low and standard doses of the vaccine-elicited responses in both parts of the immune system. The T cell response occurred within 14 days of the first dose of vaccination and the antibody response occurred within 28 days of the booster dose of vaccination.
“The robust antibody and T cell responses seen in the elderly in our study are encouraging,” said co-author Dr Maheshi Ramasamy, also from Oxford.
“The populations most at risk for serious illness from COVID-19 include people with existing health conditions and the elderly. We hope this means our vaccine will help protect some of society’s most vulnerable people, but more research will be needed before it can be sure, ”she said in the statement.
The study was published on November 19 in The Lancet.
The immune responses reported in the study do not prove that the vaccine protects against infection with the coronavirus. Phase 3 trials are currently underway to determine the efficacy of the vaccine against the disease.
To learn more about COVID-19 vaccines, see the U.S. Centers for Disease Control and Prevention.
SOURCE: The Lancet, press release, November 19, 2020