(AFP) - The Democratic Republic of Congo said Thursday it was on "maximum alert" over a mystery disease that has killed dozens of people in just over a month.

The illness causes flu-like symptoms -- fever, cough and headaches -- and has been described by Congolese authorities as "an unknown public health event".

First detected in late October, cases have so far been limited to the Panzi region, around 700 kilometres (435 miles) southeast of the capital, Kinshasa.

"We are on maximum alert, we consider this to be a level of epidemic that we need to monitor," Health Minister Samuel Roger Kamba told reporters in Kinshasa.

"In the health centres, we have counted 27 dead," he said.

He added that another 44 deaths had been reported in the community but "other possible causes" could be involved in these.

Access to the region is difficult by road and health infrastructure is lacking. Residents also face a shortage of drinking water and medicine.

Just over 60 percent of people in the region suffer from malnutrition, especially children, making it one of the highest rates in the country, Kamba said.

He recalled that the region had already suffered a serious typhoid fever epidemic two years ago.

According to initial data, the unidentified disease particularly affects younger people, with 40 percent of cases among under fives.

Epidemiologists have been sent to Panzi to take samples.

Specialists have ruled out coronavirus but have concluded it is a disease that affects the respiratory system, the minister said.

"We don't know if we are dealing with a viral disease or a bacterial disease," Dieudonne Mwamba, director general of the National Public Health Institute, said during an online press briefing by the African Union's health watchdog, Africa CDC.

"We don't even know the mode of transmission," Africa CDC chief Jean Kaseya said.

Among the 27 deaths in health centres, 17 people died after suffering respiratory distress, the minister said.

Ten died from a lack of transfusion due to a state of severe anaemia.

The DRC, one of the world's poorest countries, has in recent months been at the epicentre of an outbreak of mpox, with more than 1,000 deaths.

© Agence France-Presse