A mysterious viral disease has emerged in parts of western Democratic Republic of the Congo (DRC) in recent weeks, resulting in at least 53 deaths, officials say.
According to the World Health Organization (WHO), clinicians are particularly concerned about the short period between the onset of what appear to be symptoms of a “hemorrhagic fever” and death – around just 48 hours – prompting fears that there could be a high number of deaths if the outbreak continues.
This is the latest viral epidemic to hit the East African region in the past year, following outbreaks of Marburg and mpox diseases among others.
The DRC, in particular, is susceptible to epidemics because of its tropical climate, in which pathogens thrive, as well as its dense forests which expose people to wildlife likely to carry diseases. Many viral diseases in the country, and elsewhere, have also been linked to consumption of the meat of wild animals.
Here’s what we know about the latest viral threat:
Where has the new virus been detected?
The new virus was first detected in January, in a remote village called Boloko, in DRC’s Equateur Province. It occurred in three children who had eaten a dead bat, according to WHO. All three of the children, aged under five years old, died within 48 hours of presenting symptoms including fever, chills and headaches, between January 10 and 13.
Four more deaths were recorded in the same village among children between the ages of five and 18, all with similar symptoms, in late January. One death, on January 22, was recorded in the nearby village of Danda.
On February 9, a second outbreak of the disease was recorded in Bomate, a separate town some distance away.
By February 15, 431 cases had been recorded with 53 deaths in total according to WHO (PDF), which said the fatality rate was 10.7 percent. About half of the deaths were recorded within 48 hours of the symptoms’ onset.
What are the symptoms of the new virus?
According to the WHO, symptoms of the disease suggest it belongs to a group of diseases called viral hemorrhagic fevers (VHF), meaning they cause excessive sickness and blood loss. Recognised examples of such diseases include Ebola, Lassa fever and Marburg virus.
Symptoms recorded so far of the unknown disease in the DRC include fever, chills, headache, body aches, sweating, runny nose, neck stiffness, cough, vomiting, diarrhoea and abdominal cramps.
What do we know about the causes and nature of the new disease?
According to WHO, it’s not clear exactly what the cause of the disease is, or how the virus is transmitted. No clear link between the two outbreak points has been established yet. In a report, WHO said the lack of an obvious connection between the two hotspots could “suggest two separate health events”.
Major concerns, according to WHO, are that a “severe infectious or toxic agent” – that is, a naturally occurring virus – could be involved, and that the disease so far presents with an “exceptionally high” fatality rate.
“Key challenges [also] include the rapid progression of the disease, with nearly half of the deaths occurring within 48 hours of symptom onset in one of the affected health zones, and an exceptionally high case fatality rate in another,” WHO said.
How have authorities responded?
Earlier in February, the country’s National Institute for Biomedical Research in Kinshasa tested samples from 12 active cases, and from one deceased person. Test results have ruled out similar hemorrhagic diseases such as Ebola and Marburg virus.
Testing and contact tracing are continuing in affected locations by teams of local staff and WHO officials. However, the remoteness of the two hotspots, as well as limited lab capacity and generally weak healthcare infrastructure in the DRC could see the disease spread further, the WHO warned.
Meanwhile, isolation rooms have been set up in some villages in the region, and health workers are going to communities to brief people about the new disease.
What do experts say about the new disease?
Some health experts have said they suspect the viral disease could be zoonotic – a disease which spreads from animals to humans – because of the reports of children eating a bat, which are known to carry viruses which can be deadly for humans. In the past, viruses such as Ebola and Marburg have struck human beings who have eaten infected bats.
Until the new disease can be identified, it is difficult to know how easily humans will be able to fight it off, Dr Zania Stamataki, an associate professor in viral immunology at the University of Birmingham, told the UK’s Science Media Centre.
“If the infection originated from a virus that came from a bat, this tells us that it is unlikely that we have pre-existing immunity to this new infection for humans, so we are unprotected [and] we suffer severe disease and even death,” Stamataki said.
“[But] if the virus is similar to other viruses infecting humans – like the COVID-causing virus was similar to some common cold coronaviruses – some people may stand a chance to show less severe symptoms and recover,” she added.
Why is the DRC particularly vulnerable to the spread of disease?
The country is currently in the grips of an armed conflict in the Eastern Kivu Province led by the rebel M23 group, which recently captured the key towns of Goma (January 27) and Bukavu (February 14).
Violence there has already devastated the region’s healthcare infrastructure and has caused massive displacement in recent months. Hospitals are overwhelmed and aid workers have also been attacked.
Which other diseases have hit the region recently?
Mpox
Presently, an mpox outbreak is also ongoing in the region. DRC health officials and the WHO expressed concern about the high rate of fatalities – 4.9 percent – last June, as well as about a new, more infectious variant discovered in Kamituga, South Kivu Province, in August.
Between November 25 and January 5, more than 2,400 cases of the disease and five deaths were reported. Since the start of the outbreak, DRC had reported a total of 11,834 cases and 1,304 deaths by February 23, according to the Africa Center for Disease Control.
Recent shipments of mpox vaccines from Western donors such as the United States, Japan and the European Union enabled officials to provide vaccines to at least 50,000 people by December. It’s unclear how many vaccines are needed to cover the country’s 105 million population.
The virus has also spread to neighbouring Burundi, Uganda, Rwanda, and Kenya, although in lower numbers.
Malaria
In December, the WHO reported that a newly identified, severe case of malaria had caused 48 deaths within three months in Panzi, southern Kwango Province. That outbreak is ongoing.
Sudan virus
Meanwhile, Uganda has newly recorded cases of the Sudan virus (in the same family as the Ebola virus). Nine cases and one death have been confirmed since January 30.
Marburg virus
Tanzania is facing an outbreak of Marburg virus, in the northwest Kagera District. Since January, 10 cases have been reported including two confirmed and eight probable cases. All have resulted in death.
