Marburg outbreak could match the 2014 Ebola epidemic, researchers warn

The spread of the deadly Marburg virus in parts of Africa could evolve into a significant international outbreak following its detection in a major commercial port in Equatorial Guinea, scientists have warned.

The haemorrhagic fever, originally spread from bats, is on a World Health Organization (WHO) danger list of infectious diseases that could cause regional epidemics.

News that the Ebola-like virus had reached Equatorial Guinea’s commercial capital with a population of around 200,000 is concerning, infectious disease experts admit.

While they are not predicting a full-blown pandemic, researchers warn that a similar scenario to the 2014 West African Ebola outbreak is feasible.

That regional outbreak killed more than 11,000 people across Sierra Leone, Liberia and Guinea and spread beyond Africa’s borders.

Yet the recent successful quashing of an Ebola outbreak in Uganda late last year has also shown that outbreaks can be nipped in the bud quickly with robust surveillance and contact tracing.

Health officials in Equatorial Guinea have confirmed four cases in Bata, which has a busy deep water port and an international airport flying to neighbouring Cameroon and Gabon.

In all, cases have been recorded in three provinces across a 90-mile range, and officials admit they have been unable to establish links between all the infections.

Moritz Kraemer, associate professor of computational and genomic epidemiology at Oxford, said: “The spread of Marburg virus to the port city Bata is concerning. When new outbreaks spread into larger and more connected cities the risk of regional spread increases.

“There have now been reports of confirmed and probable cases across multiple cities and districts in Equatorial Guinea and it’s not unlikely that the extent of the outbreak is larger than currently reported. Enhanced contact tracing will help identify chains of transmission.”

Dr Michael Head, senior research fellow in global health at the University of Southampton, said: “Whilst we wouldn’t anticipate any Covid-like global spread from the current outbreak, it’s entirely possible we could see a scenario similar to the spread of Ebola across West Africa in 2014-15.

“It’s hard to tell from the outside, looking in, as to whether there is anything more that could or should have been done. However, the spread to a capital city is a concerning aspect. We don’t know for sure what will happen next, but the spread of the disease with so many cases across a wide geographical area indicates the outbreak will continue for some time to come yet.”

Little official information has emerged from the country since the outbreak was confirmed in February. An update last week disclosed there had been nine laboratory confirmed cases. Seven of those have died. There have also been 20 further suspected cases, all of whom have died.

The WHO on Thursday said it was aware of additional cases and urged the government to report them.

Equatorial Guinea's neighbours are on high alert. Health officials in Cameroon said they had tested 15 suspected cases between March 6 to March 19, but said they had not confirmed any during that period.

Meanwhile Tanzania, 2,000 miles away, has announced its own outbreak and epidemiologists are investigating if they are connected.

Jimmy Whitworth, emeritus professor at the London School of Hygiene and Tropical Medicine, said: “Outbreaks of Marburg virus are always concerning because of the high death rate in cases and its high level of transmissibility. It is uncertain if and how these widely separated cases are linked, which is also a worry.

“It is reassuring that the national authorities with the help of the WHO and other agencies are ramping up their control measures. Even so there is a high risk of further spread in Equatorial Guinea, and a moderate risk of spread to other countries within the region. The risk outside the region is assessed as low.”

As testing ramps up, more cases will be identified, predicts Dr Katherine O'Reilly, medical director at International SOS, a security and health services provider.

“If the right measures are put in place, outbreaks can be contained and we’ve seen recent examples of that,” she said.

In the most recent Ebola outbreak in Uganda in late 2022, the government was able to contain its spread with the help of international health agencies, and implement effective testing, contact tracing, screening and quarantine measures.

“Lessons are learned and shared from every outbreak, helping us manage situations as we’re now seeing with Marburg,” she said.

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