The World Health Organization on Monday said that the Ministry of Health of Guinea, the West African country, has confirmed that one patient has died of the Marburg virus disease on August 2.

“This is the first known case of Marburg virus disease in Guinea and in West Africa,” the world health body said in a statement.

Cases of the disease are extremely rare, and the last major outbreak occurred in Angola in 2005, according to the BBC.

The case fatality ratio of the Marburg virus disease is upto 88%. The infection occurs from “prolonged exposure to mines or caves inhabited by Rousettus bat colonies”, according to the WHO. It spreads between humans through direct contact with blood and other bodily fluids of those infected, and through surface transmission.

The incubation period (or, the interval between contracting the infection to the onset of symptoms) depends between two to 21 days, according to the WHO. The symptoms include high fever, severe headache, muscle pain, along with a general feeling of discomfort.

In Guinea, the virus was found in samples taken from a patient residing in the Guéckédou Prefecture in the Nzérékoré Region.

The patient had sought treatment at a local health facility near his village after he developed some of the symptoms, and was provided “supportive care with rehydration, parenteral antibiotics and treatment to manage symptoms”.

WHO chief Tedros Adhanom Ghebreyesus said that the virus could be tackled with a “concerted effort to prevent transmission and protect communities”. “WHO colleagues have been in the field with local partners since first alerts emerged and will continue to provide all needed support,” he tweeted.

WHO’s Regional Director for Africa Matshidiso Moeti lauded Guinea’s health workers for the “alertness and the quick investigative action”. He said that the potential for the virus “to spread far and wide means we need to stop it in its tracks”.

Moeti added that the WHO was working with the health authorities to put in place a swift response that builds on the country’s experience and expertise in tackling Ebola, “which is transmitted in a similar way”.

There have been twelve significant outbreaks of the Marburg virus since 1967, most of them in south and east Africa, Reuters reported.

The emergence of the Marburg virus disease comes less than two months after Guinea was officially declared Ebola-free.