Since the end of April, a number of people in northern Democratic Republic of the Congo have become sick with an “undiagnosed illness,” and three people have died as a result. Yesterday, the country’s Ministry of Health told the World Health Organization that one of the deaths was caused by the Ebola virus.

In all, nine people have come down with symptoms consistent with the virus. Based on the lab-confirmed case, the WHO has declared an official outbreak, the first in the country since 2014. Members of the DRC’s Ministry of Health and WHO have been dispatched to the area, and are expected to arrive “in the coming days,” according to Peter Salama, WHO’s executive director for emergencies. There, they will work to treat the infected, determine who they might have come into contact with, and evaluate who could be at risk for catching the disease.

The Ebola virus, which first appeared in Central Africa in the 1970s, is thought to be transmitted to humans through animal contact — either through bat droppings or meat from an infected animal. People also contract the virus when they get into contact with the saliva, blood, or feces of other infected people. Humans typically come down with the often-fatal illness within 21 days, and experience fever, headaches, and muscle pain, followed by vomiting, diarrhea, and in some cases, internal and external bleeding. A vaccine for the disease has recently been found to be extremely effective, although it’s not clear when it will go into widespread production.

The Democratic Republic of the Congo is no stranger to Ebola: one of the first reported outbreaks of the disease occurred there in 1976, when the DRC was known as Zaire. The country has experienced a number of outbreaks in the years since, and the latest outbreak was in 2014, when 66 people were infected and 49 died.

That outbreak was separate from another one that occurred at the same time in West Africa, which spread to three countries and appeared in seven others in isolated incidents. In all, almost 29,000 people were infected, and over 11,000 died. Fortunately, this latest outbreak in the DRC appears to be occurring in a remote region, according to WHO spokesman Eric Kabambi, which should help prevent it from spreading further.