The Ebola outbreak in the Democratic Republic of the Congo (DRC) has reached another grim milestone, as 506 people have now died from the Bundibugyo strain of the virus, which has no targeted treatments or vaccines. 

The DRC Ministry of Health has now confirmed 1,561 cases in the outbreak, with the epicenter in Ituri province and significant transmission in North and South Kivu provinces, as well. Thirty-three of the DRC cases are new, as are 14 of the deaths. Neighboring Uganda has 20 cases, two of them fatal.

Yesterday healthcare workers in Ituri issued a 24-hour notice of an impending strike, saying working conditions were too poor to continue. They reported unpaid benefits, low wages, and inadequate supplies since the outbreak officially began in May. 

The strike could hinder the execution of two experimental therapies that were launched this past week in the DRC. Enrollees will be given the antiviral drug remdesivir, the experimental antibody treatment MBP134, or a combination of both, with survival rates calculated during a 28-day follow-up period. 

Local residents in the hard-hit city of Bunia told news media that the trial is the first sign of hope they have had in weeks that the outbreak would be contained and stopped. 

In related news, the World Health Organization (WHO) also added the first diagnostic test for the Ebola Bundibugyo virus to its emergency use listing. The test can quickly confirm infection in blood samples. 

Experts suspect tests given in the DRC throughout the spring may have missed early infections caused by the Bundibugyo strain, instead only assessing for the more common Zaire strain of the Ebola virus. 

During a fast-moving outbreak, timely access to quality-assured diagnostic tests can make a critical difference in containing transmission.

“Public health emergencies require not only speed, but also confidence that the health products being used meet standards for quality, safety and performance,” Yukiko Nakatani, MD, PhD, WHO assistant director-general for health systems, access, and data, said in an agency press release. “During a fast-moving outbreak, timely access to quality-assured diagnostic tests can make a critical difference in containing transmission. Through this Emergency Use Listing, WHO is helping countries access trusted diagnostic tools more rapidly so that they can respond more effectively.”

In mid-May the WHO said the DRC had a capacity of approximately 200 to 400 tests per day, but it can now conduct more than 2,000 tests per day in a network of 10 laboratories across the affected provinces.

Despite increased testing, contact tracing remains difficult in the region, and a patient zero has still not been identified in this outbreak.