Four out of ten people who have weakened their immune systems show “low or undetectable” levels of Covid immunity after getting vaccinated twice, according to a major UK study.
The finding will put pressure on government scientific advisers to open the green light for a reinforcement program for the most vulnerable Britons this autumn.
Researchers at the universities of Glasgow and Birmingham measured antibody levels in 600 immunosuppressed people and compared them with healthy volunteers.
Approximately one in ten of the vulnerable group was unable to generate any detectable Covid antibody four weeks after their second dose of Pfizer or AstraZeneca.
A further 30% generated an antibody response significantly lower than that of healthy people, according to the study published as a prepress in The Lancet.
The scientists noted that almost all people who did not show an antibody response had vasculitis, a condition that causes inflammation of the blood vessels.
They added that in almost all patients, the response of T cells was similar to that of healthy adults, indicating that they were at least partially protected against Covid.
Although antibodies are the most obvious indicator of immunity, T cells (a type of white blood cell) also play a crucial role in preparing the body for disease.
Experts behind the study have called for the Joint Committee on Vaccination and Immunization (JCVI) to approve booster doses for immunocompromised people in the coming weeks.
Infections, deaths and revenue from Britain’s daily covides have been rising slowly but steadily for several weeks, prompting fears of a new wave when schools are turning back and bolstering the argument for proponents.
Researchers at the universities of Glasgow and Birmingham measured antibody levels in 600 immunosuppressed people and compared them with healthy volunteers. Approximately one in ten of the vulnerable group was unable to generate any detectable Covid antibody four weeks after their second dose of Pfizer or AstraZeneca. 30% more generated an antibody response significantly lower than that of healthy people, according to the study published as a prepress in The Lancet
Immunocompromised people include those with certain types of arthritis, inflammatory bowel disease, and some cancers.
According to sources, the JCVI is poised to launch third doses to this group starting in September, but will retain a massive reinforcement campaign for whole age groups and expect more evidence of the benefit.
To determine how much protection immunosuppressed people had from vaccines, the research looked at the levels of antibodies and T cells in 600 of them before a vaccine, after a dose, and after both shots. . They compared it with samples taken from 231 healthy individuals.
Four weeks after receiving a second dose, 100 per cent of healthy Britons were producing antibodies.
But only 89% of immunosuppressed people did, meaning more than one in ten people had zero antibodies to protect themselves against the virus.
And there was even less in some subgroups of immunocompromised people.
For example, 72% of people with vasculitis did not produce antibodies after two doses.
The researchers said these patients were taking medications that interrupt the production of antibodies to calm their immune system, making it very difficult for them to mount a vaccine response. Patients with solid cancer used to have high levels of antibodies.
They claimed their findings “strongly” support giving booster doses to people with chronic illnesses or immunosuppressive drugs.
Professor Iain McInnes, an expert in rheumatoid and psoriatic arthritis at the University of Glasgow and leader of the study, said the absence of an antibody response among some vulnerable was worrisome, but said there were positive aspects. which they would take out of the study.
He noted that it is unclear what the correlation is between antibody response and the likelihood of contracting an infection or the severity of the infection.
Professor McInnes said: “I would point out that the group of patients who did not make antibodies was mostly in the vasculitis group and the vasculitis group is a group of rare diseases in this country.”
And the “vast majority” of people who have solid cancer (more cancerous growth than blood), as well as those who have immune disease, inflammatory bowel disease, or arthritis, will probably do well, but there are more. work should be absolutely reassuring, ‘he said.
The researchers also found that both healthy and immunosuppressed patients, including those with vasculitis, had puncture-like T cell responses.
And Professor McInnes said most immunosuppressed patients had an immune response that seemed “remarkably similar” to a healthy control group.
About 60 percent of participants with “fairly significant conditions in fact look just as effective as people who, on the other hand, have an intact immune system,” he added.
Britain is pushing harder and harder to launch its own mass launch.
JCVI is expected to have only third-dose green light for vulnerable adults with suppressed immune systems.
The promoters will certainly be offered to the 3.7 million Britons classified as “clinically extremely vulnerable”, with diseases such as cancer.
But it was initially expected that the program would be open to all over-50s, key workers and sick patients, which would include up to 32 million people.
Some scientists have said vaccines should be used to administer first doses to people in other countries before third doses are offered in the UK.
Professor Eleanor Riley, an expert in immunology and infectious diseases at the University of Edinburgh, said the findings were “unsurprising” but “important”.
Not surprisingly, many at-risk groups have lower antibody responses after two doses than healthy people, he said.
But it is promising that many had a detectable antibody response after a dose that increased after a second time, Professor Riley said.
He added: “It is very possible that they will have an even better response after a third dose of vaccine.
“Therefore, these data support the idea that people with specific co-morbidities should be prioritized for a booster dose of vaccine in the coming weeks.”
Professor Neil Mabbott, president of immunopathology at the University of Edinburgh, said the findings suggest that reinforcements should be given to those with weakened immune responses.
He said: “There is a lot of debate in the UK about whether we should launch reinforcements to adults who have already received two doses.
“Of course, we currently do not have a reliable serum marker that can tell us if it is protected and to what extent an individual develops from severe Covid disease after vaccination.
‘Despite this, the results of this study provide useful evidence to inform these decisions.
“This study supports the suggestion that if booster shots should be used, priority should be given to those like the individuals in this study, who have weakened immune responses and responded poorly to their previous vaccinations.”