The number of laboratory-confirmed Ebola cases in the Democratic Republic of the Congo has risen to 1,155, including 304 deaths, health authorities announced.

According to the latest bulletin from the country’s health authorities, 37 new cases and five additional deaths were confirmed within 24 hours.

Officials said improvements in epidemiological and laboratory surveillance have made it possible to detect cases more quickly, while also confirming that transmission of the virus continues to rise on a weekly basis.

The current outbreak, declared on May 15, is caused by the Bundibugyo strain of the Ebola virus, a rarer form for which there is currently no specific approved vaccine or treatment. Most previous Ebola outbreaks in DR Congo were caused by the Zaire strain, for which a vaccine is available.

This is the 17th Ebola outbreak recorded in the vast Central African country, which has a population of around 100 million.

Health authorities believe the virus may have been circulating undetected for some time before the outbreak was officially declared.

Ebola has killed at least 15,000 people in Africa over the past 50 years, while the disease’s fatality rate can range from 25% to 90%, according to the World Health Organization.

In DR Congo, the country’s deadliest Ebola outbreak occurred between 2018 and 2020, killing nearly 2,300 people out of around 3,500 recorded cases.