A vaccine that has been around for 80 years and is part of the national childhood immunisation programme in India has found to induce enhanced frequencies of memory T and B cells and 2 dendritic cell subsets in elderly individuals, the Indian Council of Medical Research has found. So can a vaccine that has been around since the year 1921 protect against Covid-19? Yes, says ICMR.
BCG vaccine has a documented protective effect against meningitis and disseminated TB in children.
In April this year, an article published in the Lancet suggested that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a single-stranded positive-sense RNA virus, and the BCG vaccine has been shown to reduce the severity of infections by other viruses with that structure in controlled trials. Dr Tedros Adhanom Ghebreyesus, the director general of the World Health Organization, who was one of the authors of this article that said that the BCG vaccine has the potential to “bridge the gap before a disease-specific vaccine is developed”.
The study to evaluate the effectiveness of the BCG vaccine in reducing morbidity and mortality in elderly individuals in Covid-19 hotspots in India was undertaken by the Indian Council of Medical Research. As part of the study protocol, the immune responses engendered by BCG vaccination in a group of elderly individuals. Previous studies in elderly individuals have shown that BCG vaccination protected against respiratory infections in Indonesia, Japan, and Europe.
Elderly individuals, between 60-80 years of age, residing in hotspots for SARS-Cov2 infection were included in the study between July 2020 and September 2020 in Chennai, obtaining informed written consent from the study participants.
Elderly population positive for SARS-Cov2 infection by either antibody (serology) or PCR test; HIV infected or individuals with malignancy or on immunosuppressive drugs or transplant recipient and those on dialysis or anti-psychiatric medications or hypersensitivity to vaccinations were not included in the study. Also, those who were diagnosed with tuberculosis (TB) in the previous six months or were currently on anti-TB treatment were not included in the study. Fifty four participants received a single dose of BCG vaccine (Freeze-dried) manufactured by Serum Institute of India, Pune.
Scientists at the ICMR have found that the vaccine induces increased memory cell responses and total antibody production in elderly. BCG vaccination increases natural and adaptive immunity among healthy elderly individuals and was associated with enhanced innate and adaptive memory cell subsets, as well as total antibody levels in elderly individuals, suggesting its “potential utility in SARS-Cov2 infection by enhancing heterologous immunity”.
A professor from Delhi’s Jawaharlal Nehru University, Gobardhan Das, expressed dismay at the fact that this study was delayed. He said that it could have been done earlier and lives could have been saved.
On May 3, he tweeted “My grant proposal on BCG recombinant vaccine for Covid-19 has been turned down by Indian government agency citing its a bad idea. Same government is conducting multiple trials based on my idea.”
On Wednesday, he posted another tweet saying that he had been saying this since March. “I wrote to many authorities. Several countries started, but we ignored months. We also published our paper months back. Even my grant proposal was denied. What we gained?, Lost many precious lives.”
In July this year, Dr Randeep Guleria, Director AIIMS told News18 that there could be a link between BCG vaccine and India’s low mortality rate. “The mortality in India continues to be low. This shows we have a better immune system. Maybe this is because of BCG vaccine” he said.