WHO declares Rwanda’s Marburg outbreak officially over

The Marburg outbreak in Rwanda is officially over, health authorities said, putting an end to the Central African country’s first bout with the highly lethal Ebola-like virus.

No new Marburg cases have been reported in at least 42 days, and the last patient tested negative for the virus twice, according to the World Health Organization (WHO), following the official protocol to declare an end to infectious disease outbreaks.

Since the outbreak was confirmed in late September, officials reported 66 cases and 15 deaths of the Marburg virus, which causes severe viral haemorrhagic fever and typically has a fatality rate of between 24 per cent and 88 per cent.

In the Rwandan outbreak, the fatality rate was about 23 per cent, the WHO said. 

Nearly 80 per cent of the cases were among health workers who were infected while caring for sick patients.

Swift response to the outbreak

While there is no approved vaccine or antiviral treatment for Marburg, Rwandan health authorities responded quickly to the outbreak with increased disease monitoring, diagnostic testing, contact tracing, and infection control measures put in place.

Response teams in the area conducted more than 7,400 Marburg tests, with up to 350 samples tested every day at the Rwanda Biomedical Center, according to the London School of Hygiene and Tropical Medicine.

Frontline healthcare workers were also immunised with an experimental Marburg vaccine from the US-based Sabin Vaccine Institute, which sent about 2,700 doses to Rwanda.

The country also launched the first-ever clinical trial testing Marburg treatments in October.

These efforts helped halt the spread of the virus, the WHO said. 

Cases fell by half between the second and third weeks after the outbreak was detected, and then by about 90 per cent thereafter.

Daniela Manno, an infectious disease epidemiologist at LSHTM, said the outbreak was especially difficult to control because the virus has spread across multiple regions and had a “significant impact” on health workers.

“As with any highly virulent infection, healthcare workers are among those at the highest risk due to close contact with patients, particularly when the disease is not promptly identified and strict infection control measures are not adopted,” Manno said in a statement.

Measures to ensure response to flare-ups

Dr Brian Chirombo, the WHO’s representative in Rwanda, said the country’s “robust response” to the Marburg outbreak underscores the importance of political leadership, international cooperation, and a strong health system in combating public health threats.

The Marburg virus spreads to people from fruit bats. Human-to-human transmission occurs through direct contact with the bodily fluids of infected people, surfaces, or other items, and it causes symptoms similar to Ebola, such as fever, fatigue, diarrhoea, and vomiting.

ADVERTISEMENT

In 2023, Marburg outbreaks in Tanzania and Equatorial Guinea killed dozens of people.

Jean Kaseya, director general of the Africa Centres for Disease Control and Prevention (Africa CDC) had previously said the risk that Marburg would spread beyond Rwanda was extremely low.

The WHO said it will keep working with Rwandan health officials to “maintain critical measures to ensure swift detection and response in case of any flare-up or new spillover of the virus”.