An advisory group to the World Health Organization (WHO) recommended Monday that people with weakened immune systems who have been fully vaccinated against the coronavirus should get an additional dose of any WHO-approved COVID-19 vaccine.
"SAGE recommended that moderately and severely immunocompromised persons should be offered an additional dose of all WHO EUL COVID-19 vaccines as part of an extended primary series," the Strategic Advisory Group of Experts on Immunization (SAGE) said in a statement.
Vaccines will not be the only factor resulting in the end of the COVID-19 pandemic but are an important contributor to its end, experts from the group said, speaking about boosters and hesitancy.
At a UN press conference, the group said they met from Oct. 4-7 to review the latest information and data on vaccines for COVID-19 vaccines and wanted to examine the issue more closely.
They said COVID-19 vaccine rollouts have started in all WHO regions, though the pace of vaccination varies considerably between and within regions, mainly driven by unequal access to vaccine supply.
Fifty-six countries found predominantly in the African and Eastern Mediterranean regions were unable to achieve the target of fully vaccinating 10% of their populations by September 2021, mainly because of a lack of vaccine doses.
"There's been much in the press, and much in the scientific literature...about the use of additional doses beyond those doses that were tested in the context of clinical trials, and the phrasing that is used around additional doses is often referred to as a booster dose," said Dr. Katherine O'Brien, the WHO's director of the Department of Immunization, Vaccines and Biologicals.
SAGE made its call since immunocompromised individuals are less likely to respond adequately to vaccination following a standard primary vaccine series and are at high risk of severe COVID-19.
- Complex issue around vaccines
"This is a complex issue around the different vaccines, the different risk groups, variants that are circulating, the time since vaccination, in other words waning of immunity or potential waning of immunity," said O'Brien.
“The outcomes of most interest are the severe outcomes: hospitalization, serious disease and death, and so all of these issues and topics will be looked at.
"Vaccines are not going to be the only thing that is going to result in the end of the pandemic, but they're an important contributor to the end of the pandemic," she added.
She said some estimates are expecting over 14 billion doses of vaccine in 2022.
That is more than enough to address the targets that the WHO has set out in its strategy of 70% full global vaccination coverage by the middle of 2022.
"The question is really now a sense of time urgency that those vaccines need to go to the places that are lagging," O'Brien said.
She noted that around vaccine demand and acceptance and hesitancy are complex issues that are not uniquely about vaccines.
"They are also from the evidence that we see they're very much about social structures. They're about confidence in authority figures and authority institutions, which go well beyond the issue of vaccines."
Dr. Alejandro Cravioto, the SAGE chair, said: "It is interesting that in some countries where there is a huge availability of vaccines, there is this hesitancy, while in others, people are rushing to get registered and queue for hours, sometimes to be able to get a dose."