Woman holding a baby

A old vaccine for new diseases?

For more than a decade, Professor Nigel Curtis of the Murdoch Children’s Research Institute (MCRI) in Melbourne has been working on developing the potential for Bacille Calmette-Guérin vaccine (BCG) – a common tuberculosis vaccine – to help protect against an array of other allergies and infections.

Trials suggest BCG improves the performance of the innate immune system – our first line of defence – at least in infants.

But the arrival of the COVID-19 pandemic offered an opportunity to expand that study, in collaboration with European researchers, to investigate whether BCG can offer some protection against the SARS-CoV2 – the virus that causes COVID – and other pathogens.

“At the end of 2019 we thought that it would take at least two years to make a vaccine, so we thought whilst we’re waiting for these vaccines, we could at least try to protect healthcare workers on the front line by boosting their immune system,” says Professor Curtis.

“But within a few months, it became very obvious that Australia, with low infection rates, was exactly the worst place to be doing a COVID-related trial.”

The Gates Foundation came to the rescue funding an expansion of the trial.

“We rapidly expanded to Europe because at that stage, the COVID peak was in Italy and the UK.”

Using the methodology established in Australia, trial sites were set up in the UK, the Netherlands, Spain and, later, Brazil.

From its humble origins in Melbourne, the study now involves 34 sites worldwide, and has recruited nearly 7000 healthcare workers, with results due around June.

“The study has also allowed us to collect an enormous amount of data that allows us to understand, not just how BCG might work, but also a bit more about why some people get severe diseases and some don’t,” says Professor Curtis.