Hospitals in Madagascar have seen more than 1,150 cases since August, despite the picturesque island nation commonly recording a few hundred cases of plague every year.
And as the disease spreads to urban areas, health workers battling to slow the rate of infection have warned the stigma associated with the illness is undermining their efforts to contain it.
Latest data from the World Health Organisation (WHO) says 39 healthcare workers had been infected so far, and the Red Cross is reportedly using the same burial methods employed during the 2014-2016 Ebola outbreak in West Africa.
Plague, also known as the black death, was one of a series of infectious diseases which killed around 50 million people in Europe during the Middle Ages.
The most common strain found in Madagascar is the bubonic plague, which spreads through the bites of infected fleas.
But the WHO says the disease is now being passed on from person to person through the more contagious pneumonic form.
The outbreak has killed at least 97 people so far.
Elhadj As Sy, secretary general of the International Federation of Red Cross and Red Crescent Societies, said he was concerned some people were not seeking treatment.
He told Reuters the increased number of cases was causing panic and some people were ashamed to admit they were infected.
Mr Sy said the stigma of the disease could “drive people underground and that may result in us losing some of the contacts we are tracing in order to contain the outbreak.
“The number of cases is growing by the day.
“Our volunteers are working in communities convincing people to seek help.”
Plague can be cured using powerful antibiotics, but it is often fatal if people are not treated.
And the longer those infected go without seeking help, the greater the chance of them passing on the disease.
Hospitals in Madagascar are reportedly on high alert and are implementing preventative measures.
Mamy Randria, head of the infectious diseases clinic at the public hospital in the capital Antananarivo, said: “We are limiting the number of visitors, and stipulating that all the health professionals wear a mask when they meet a patient.
“People are aware of the problem – they know that if you have a fever and have other symptoms, you need to seek medical attention.”
Earlier this month, experts warned the disease could become an epidemic in the United States.
US doctor Peter Small, a clinician trained in infectious diseases who has been working in Madagascar for several years, told Newsweek: “We have plague cases every year out west.
“The only reason we have cases and not epidemics is because we invest in a public health system.
“However, if we continue to underinvest in public health, those cases could become epidemics here in the US.”