A vaccine that protects against the coronavirus can still be misused and is unlikely to stop the spread of the virus, the authors of a new review have concluded.
In an article published on Wednesday in The Lancet, the researchers say that the use of vaccines, in their view, can result in a “multipresing dissemination” of the disease.
“This may be because the vaccine itself can be misusing,” the authors wrote.
“In this case, this means that the vaccine is misused to propagate the disease, and it has a very high likelihood of spreading to other susceptible populations.”
A study last year by the UK’s National Institute for Health Research, which is part of the European Union’s national research agency, suggested that the coronivirus could spread among people with existing immune deficiencies, with up to 10 per cent of them potentially at risk.
In this new study, the British researchers focused on three vaccine classes: vaccines made by Novartis, GlaxoSmithKline and Pfizer, and a smallpox vaccine produced by Merck.
The study used data from more than 8,000 people who received one or more of the three vaccines between 2010 and 2013, and the data included information about whether they had been vaccinated and how often they had received them.
“We found that there was a clear increase in the proportion of people who had received the vaccine that was not at the start of the study,” Dr David Good, one of the authors from the British group and a member of the Cochrane Collaboration, told the BBC.
“The number of vaccinated was actually higher than the number of those who had not.”
Good said that the increase in vaccination rates could have been due to the “increasing frequency of vaccination” as the pandemic progressed.
“A large proportion of the vaccine was misused,” he said.
“This means that in our view there is a very strong likelihood that vaccines are misused by those who have not been vaccinated.”
The authors of the review say that there is no evidence that vaccine misuse can stop a pandemic.
“There is no convincing evidence that vaccines that are misusable are harmful to human health,” they wrote.
“However, misusing vaccines is a real risk and, given the current risks to public health, we should be concerned about any increased risks to the public.”
A review of the use and misuse of vaccines in Europe by the US Centers for Disease Control and Prevention (CDC) has found that around one in 10 vaccines is misusing.
Good said the current study was a “pro-active effort” that had highlighted “serious problems” with the use or misuse of the vaccines.
“The use of unlicensed vaccines is likely to increase, particularly among those who do not have access to healthcare and who are not well served by the current vaccine supply system,” he told the New Scientist.
“I would like to see an increased emphasis on the development of alternatives to the current vaccines.”
Good is one of two authors on the review, with another being Dr Thomas Raff from the University of Chicago, who was not involved in the research.
In their opinion, the findings of the new study highlight the need to take action.
“It’s a great idea to take the time to do a proper safety study and do all the necessary research on vaccine misuse before you use it, but this is only a first step in a long process to develop a safe vaccine,” he added.