University of Oxford scientists behind the AstraZeneca (AZ) Covid-19 vaccine have begun trialling a new plague vaccine in participants.

The Phase I study, which is based on the same viral vector used in the AZ coronavirus vaccine, will see 40 healthy adults between the ages of 18 and 55 receive the new vaccine to assess its efficacy and identify potential side effects.

Plague: a continued global threat

Plague, a centuries-old disease caused by the Yersinia pestis bacterium, is best known for the Black Death pandemic that ravaged the European population in the 1300s – but cases are still seen in areas of Africa, Asia and America today.

The most recent outbreak of plague occurred in Madagascar in 2017; a total of 2,417 cases of plague were confirmed, and the country saw 209 deaths.

Though antibiotics to treat plague are available, many of the areas hit by plague are rural or remote locations. A plague vaccine would provide a preventative method to protect against the disease in these areas.

There are three types of plague: bubonic, pneumonic and septicaemic. The bubonic form has a 30% to 60% fatality rate if left untreated, while the pneumonic form almost always results in death. Both bubonic and pneumonic plague can develop into septicaemia, a life-threatening infection of the blood.

Director of the Oxford Vaccine Group Professor Sir Andrew Pollard said: “The coronavirus pandemic has shown the importance of vaccines to defend populations from the threat caused by bacteria and viruses.

“Plague threatened the world in several horrific waves over past millennia, and, even today, outbreaks continue to disrupt communities. A new vaccine to prevent plague is important for them and for our health security.”

The trial, funded by Innovate UK, will run for at least 12 months.