An outbreak of pneumonic plague in the Democratic Republic of Congo has killed 42 people over the past two months, the World Health Organization reports.
Plague is passed to humans through flea bites
Field tests looking at more than 600 suspected cases confirmed the presence of the disease near Wamba, in the northern province of Oriental.
But the WHO added that further laboratory tests were needed.
It said the scale of infection might be less as so many cases would normally mean more deaths.
"Preliminary results from a rapid diagnosis test in the field found three samples positive out of eight," the WHO said.
Suspected pneumonic plague killed 100 people in eastern DR Congo early this summer.
Plague is endemic in many countries in Africa, in the former Soviet Union, the Americas and Asia, according to the WHO.
If left untreated, it has a case-fatality ratio of 30%-60%.