Dozens of workers at an Ebola treatment center in northeast Congo have gone on strike over unpaid salaries and bonuses, creating a significant obstacle for the country's ongoing battle against its deadliest Ebola outbreak.

The striking staff at Rwampara General Hospital in Ituri province, which is the epicenter of the outbreak, includes epidemiologists, case investigators, drivers, and gravediggers. They stated they have not received payment from Congolese authorities for two months. The protest led to the shutdown of the hospital and blockades on the road leading to it, with one tire reportedly burned outside the facility.

"We don’t know how it is possible to not have been paid for two months," Bahati Claude, a health worker at the hospital, told The Associated Press. "We don’t want to give up the job."

Congo declared this Ebola outbreak on May 15, though the disease had been transmitting for weeks prior to official detection, according to the World Health Organization. The outbreak is caused by the rare Bundibugyo virus. The delay in confirmation was partly due to initial testing for a more common type of Ebola.

The Congolese health minister, Roger Kamba, stated last week during a visit to Ituri that the government is in the process of verifying the payroll for those working to control the outbreak, as some individuals not involved in the response appear to have been added to the list of employees.

"We must ensure that these payments reach the right people," Kamba said. "We have faced a few challenges, notably changes to the lists, which have led to complaints from people saying they are not being paid even though they are working. We have the means to sort this out."

As of the latest reports, Congolese authorities have confirmed 1,926 cases of the virus, resulting in 702 deaths. The World Health Organization's Director-General, Tedros Adhanom Ghebreyesus, announced that a second U.S. citizen, identified as a humanitarian worker in eastern Congo, had been transferred to Germany after contracting Ebola. The first American to test positive for the virus was a doctor who was working in Congo during the early stages of the outbreak.

The treatment center where the strike is occurring is separate from another facility in Ituri where a study of two experimental treatments for Ebola began earlier this month.