BCG vaccine used in Africa could reduce symptoms, but not ‘cure’ or ‘vaccine’ for Covid-19
“Has Africa had the cure all along?” asks a 5 April 2019 Facebook post by a South African radio presenter. The post claims that a tuberculosis (TB) vaccine used in some African countries is being considered as “a possible vaccine” for the coronavirus that causes Covid-19.
“Don’t get too excited, but scientists are starting to look at our TB vaccine B.C.G. as a possible vaccine against the worst elements of the Coronavirus COVID-19,” the post reads.
Several clinical trials are testing whether the vaccine can help people to fight Covid-19. But is it a vaccine or cure for the new coronavirus disease?
BCG vaccine associated with lower death rates
The BCG vaccine – short for Bacillus Calmette-Guerin – has been found to be effective against TB, leprosy and other infections. The World Health Organization recommends that the vaccine be given to healthy infants at birth in any countries with a high incidence of TB or leprosy. South Africa requires that the vaccine be given to infants at or shortly after birth.
BCG is a bacterial vaccine created using a strain of bacteria first isolated in cows in 1902. It was first used on people in 1921.
The vaccine has now been associated with lower Covid-19 death rates. The Facebook post links to a New York Times article about two clinical trials – in Australia and the Netherlands – of the vaccine’s possible ability to boost the immune system. This could help protect healthcare workers against Covid-19 symptoms.
South African author Alan Knott-Craig, son of the telecoms industry leader of the same name, has also spoken hopefully about BCG on his personal blog. (Knott-Craig’s statements about BCG have also been submitted to Africa Check for review.)
He writes: “It may just turn out that most South Africans are safe” from Covid-19 “because it’s mandatory to have a Bacille Calmette-Guerin (BCG) vaccination when they are born”.
Knott-Craig also refers to the New York Times, among other publications. “We may just be able to end the national lockdown, and re-start the economy,” he says.
BCG vs Covid-19
The two clinical trials are yet to produce results. Until then, here are some things we know about BCG and its effects on Covid-19.
Importantly, experts have not suggested that the BCG vaccine is a “cure” or vaccine for Covid-19. The clinical trials are being conducted on healthcare workers, not the general population, and with no expectation that BCG will prevent them from contracting the disease – or cure them if they do.
A report on the trial in the Netherlands suggests that the vaccine may provide “partial” protection or limit the severity of the disease. Titled “Reducing Health Care Workers Absenteeism in Covid-19 Pandemic Through BCG Vaccine”, the trial is being conducted with the hope that reducing severe symptoms in healthcare workers will allow them to stay at work, where they will be needed during the pandemic.
The Australian trial has similar aims. It is designed “to determine if BCG vaccination reduces the incidence and severity of Covid-19”, and will also be tested among healthcare workers. The researchers have not indicated that BCG could be a “cure” for Covid-19.
Indeed, the New York Times article cited both by Knott-Craig and the Facebook post quotes Nigel Curtis, one of the researchers in the Australian trial. Curtis told the Times: “Nobody is saying this is a panacea … What we want to do is reduce the time an infected health care worker is unwell, so they recover and can come back to work faster.”
The interest in BCG has been sparked by a study from the New York Institute of Technology. The study found lower infection and death rates in countries with mandatory BCG vaccinations.
Prof Salim Abdool Karim, an epidemiologist and chair of the South African ministerial advisory committee for Covid-19, has said that he is “sceptical” of the study’s results. “I asked our colleagues in China whether they saw any difference in patients who had BCG,” TimesLive quotes him as saying, “and the answer was ‘No’.”
The World Health Organization has also commented on BCG vaccination, saying: “There is no evidence that the Bacille Calmette-Guérin vaccine (BCG) protects people against infection with Covid-19.” The WHO does not advise the use of the vaccine.
While the New York institute’s study found lower rates of Covid-19 in countries with mandatory BCG vaccination, they were not unaffected. For example, Knott-Craig cites Portugal as a country where mandatory vaccination has lowered the impact of Covid-19. Yet Portugal was still forced to declare a state of emergency on 18 March 2020, which was later extended until at least 17 April. The country’s Directorate-General of Health has also confirmed nearly 17,000 cases of Covid-19 as of 14 April 2020.