Health officials are struggling to contain the spread of a plague outbreak that is currently simmering away on the island of Madagascar. So far it has killed around 124 people and infected some 1,100 others, as the World Health Organization (WHO) warns against travel to regions affected as the disease has developed from the less infectious bubonic plague to the more virulent pneumonic variety.

But there are also warnings that the spread of the disease may be being fuelled by a particularly gruesome ritual carried out by some communities in rural Madagascar. Known as ‘famadihana’ in Malagasy, the ceremony involves exhuming the dead from their graves and wrapping them in fresh cloth, before dancing the corpses around the tombs and replacing them. According to AFP, the recent outbreak of plague has coincided with the peak occurrence of the ritual.

“If a person dies of pneumonic plague and is then interred in a tomb that is subsequently opened for a famadihana, the bacteria can still be transmitted and contaminate whoever handles the body,” the health ministry chief of staff, Willy Randriamarotia, reportedly said.

It is important to note, however, that an outbreak of the plague in Madagascar is not actually that unusual, as the bacteria that causes it, Yersinia pestis, is present in the natural environment, and that this ceremony is nothing new. What is of more concern is that it has become pneumonic, meaning that the bacteria is now infecting the lungs of patients, and so is easily spread by droplets of mucus and water released through coughing.

With the development of the outbreak to pneumonic plague, there are increasing fears that the disease will spread as people travel from Madagascar to other East African nations. So far, South Africa, Mozambique, Tanzania, Kenya, Ethiopia, Comoros, the Seychelles, Mauritius, and Reunion have upped their screening at airports to look out for people who may have symptoms.

“This outbreak carries a moderate risk of spread to neighbouring Indian Ocean islands,” said the WHO, and already there has been at least one suspected case of the disease being spread to the Seychelles, as the Seychellois Ministry of Health notified the WHO on October 10 of a man who had recently returned from Madagascar presenting symptoms of the pneumonic plague.

While untreated, the pneumonic plague can kill within a very short period of time, sometimes within just 18 hours, so the WHO recommend rapid diagnosis and treatment. Those who do contract the disease can be given common antibiotics, which are known to be effective if given in time.