Public health officials in Africa urged caution Thursday as Congo’s health minister said the government was on alert over a mystery flu-like disease that in recent weeks killed dozens of people.

Jean Kaseya, the head of Africa Centers for Disease Control and Prevention, told reporters that more details about the disease should be known in the next 48 hours as experts receive results from laboratory samples of infected people.

“First diagnostics are leading us to think it is a respiratory disease,” Kaseya said. “But we need to wait for the laboratory results.” He added that there are many things that are still unknown about the disease — including whether it is infectious and how it is transmitted.

Authorities in Congo have so far confirmed 71 deaths, including 27 people who died in hospitals and 44 in the community in the southern Kwango province, Health Minister Roger Kamba said.

“The Congolese government is on general alert regarding this disease,” Kamba said, without providing more details.

Of the victims at the hospitals, 10 died due to lack of blood transfusion and 17 because of respiratory problems, he said.

The deaths were recorded between November 10 and 25 in the Panzi health zone of Kwango province. There were around 380 cases, almost half of which were children under the age of 5, according to the minister.

The Africa CDC recorded slightly different numbers, with 376 cases and 79 deaths. The discrepancy was caused by problems with surveillance and case definition, Kaseya said.

Authorities have said that symptoms include fever, headache, cough and anemia. Epidemiological experts are in the region to take samples and investigate the disease, the minister said.

The Panzi health zone, located around 700 kilometers from the capital, Kinshasa, is a remote area of the Kwango province, making it hard to access.

The epidemiological experts took two days to arrive there, the minister said. Because of the lack of testing capacity, samples had to be taken to Kikwit, more than 500 kilometers away, said Dieudonne Mwamba, the head of the National Institute for Public Health.

“The health system is quite weak in our rural areas, but for certain types of care, the ministry has all the provisions, and we are waiting for the first results of the sample analysis to properly calibrate things,” Kaseya said.

Mwamba said that Panzi was already a “fragile” zone, with 40% of its residents experiencing malnutrition. It was also hit by an epidemic of typhoid fever two years ago, and there is currently a resurgence of seasonal flu across the country.

“We need to take into account all this as context,” Mwamba said.

A Panzi resident, Claude Niongo, said his wife and 7-year-old daughter died from the disease.

“We do not know the cause, but I only noticed high fevers, vomiting … and then death,” Niongo told The Associated Press over the phone. “Now, the authorities are talking to us about an epidemic, but in the meantime, there is a problem of care [and] people are dying.”