WHO warns over spread of Marburg virus after Tanzania deaths

The World Health Organization has urged African health authorities to step up monitoring and clinical care after Tanzania reported its first outbreak of the virulent Marburg virus.

Marburg spreads to humans from fruit bats and is passed on through direct contact with the bodily fluids of infected patients. The disease is highly virulent, causing haemorrhagic fever and killing up to 88 per cent of those it infects. It belongs to the same family of viruses as Ebola, another deadly disease whose most severe outbreak occurred in several west African countries from 2013-16.

Tedros Adhanom Ghebreyesus, the WHO’s director-general, said on Thursday that eight Marburg cases had been reported in Tanzania, including five deaths. Nine cases have been confirmed in Equatorial Guinea after an outbreak was first reported in the west African country last month.

The WHO was “leading trials of vaccines in the context of the emergency”, he added. There are no vaccines or antivirals approved to treat the illness, with treatment focusing on the rehydration and clinical care of patients.

Tanzania’s Marburg outbreak involved 161 contacts. Its east African neighbours Uganda and Kenya have enhanced border surveillance to help reduce transmission.

Tanzania’s health minister, Ummy Mwalimu, said her government had “managed to control the rate of the new infections of Marburg. So far it has not been reported anywhere else apart from the affected area.”

“We’re determined to end the outbreak within the shortest period of time,” she added.

Abdirahman Mahamud, interim director of the WHO’s alert and response co-ordination department, praised the countries’ responses in dealing with the outbreaks, as the cases were located in remote regions.

WHO said it assessed the risk posed by the outbreak as “very high” at the national level, “moderate” at the regional level and “low” at the global level.

The batch of cases reported in Equatorial Guinea were about 150km apart, “suggesting wider transmission of the virus”, according to the WHO.

Mahamud said the global health body was working “very closely” with Cameroon and Gabon, Equatorial Guinea’s neighbours, as some of the latest cases were in border areas. The subregional risk was “very high”, he added.

“It’s happening right at the border,” he said, urging Cameroon to “increase readiness”.

Marburg incubation ranges from two to 21 days, according to the WHO. The virus is traced back to laboratory work on African green monkeys in the German city of Marburg, where the first cases were detected along simultaneous outbreaks in Frankfurt and Belgrade in 1967. There have been regular outbreaks in Africa since the first cases in South Africa in 1975.