A mysterious illness that first emerged in three children who ate a bat has claimed the lives of more than 50 people in northwestern Democratic Republic of Congo over the past five weeks, health experts report.
The disease, which manifests with symptoms such as fever, vomiting, and internal bleeding, has caused widespread concern due to the rapid progression of the illness. In most cases, death occurs within 48 hours of the onset of symptoms. “That’s what’s really worrying,” said Serge Ngalebato, medical director at Bikoro Hospital, a key regional monitoring center.
While these “hemorrhagic fever” symptoms are typically associated with deadly viruses like Ebola, dengue, Marburg, and yellow fever, tests of over a dozen samples have ruled out these common diseases.
The outbreak, which began on January 21, has resulted in 419 reported cases and 53 deaths. The first case was traced back to the village of Boloko, where three children consumed a bat and died within two days. This raises concerns about the risks of diseases jumping from animals to humans, a phenomenon that has become increasingly common in Africa in recent years. The World Health Organization (WHO) noted that animal-to-human disease transmission has surged by over 60% in the last decade.
The outbreak spread to the village of Bomate on February 9, prompting further testing. Samples from 13 suspected cases were sent to the National Institute for Biomedical Research in Kinshasa, DR Congo’s capital, for analysis.
While all samples tested negative for common hemorrhagic fever diseases, some did show signs of malaria.
Science Media Centre interviewed Dr Zania Stamataki, Associate Professor in Viral Immunology, University of Birmingham on the mysterious illness:
What do we know about the outbreak, potential causes, or modes of transmission?
“The symptoms shown in these infections are different to the alarming infection caused by severe malaria in the DRC in the end of last year, with patients reporting nose bleeds, vomiting blood and internal bleeding. The time from symptom onset to death is 48 hours, which is very alarming.
“We know that the patients tested negative for known haemorrhagic fever viruses such as Marburg and Ebola. Other haemorrhagic fever-causing pathogens are investigated.
“The modes of transmission are unknown. The authorities are also looking at culprits beyond infection, for example poisoning by a toxic agent.
How is the situation being controlled, Are we likely to see more cases in the coming days?
“It is possible that we will see more cases. The incidents are currently correctly treated like an outbreak of infection, but it is not known how infection is transmitted, which makes it more difficult to contain. The best way to contain the outbreak is to isolate patients and stop travel in affected regions to prevent transmission.
“Viral infections can remain silent in the body for days before we start showing any symptoms. This is called the virus “incubation period”. While infected, a person could feel well enough to travel and mix with others in social events, which aids transmission.
How likely is it that this disease will spread across borders, potentially into the UK?
“Infections know no borders and do not respect country lines. People travel and infections travel with them, either hitching a ride in a person or in animal carriers, so one cannot exclude spread outside of a country’s borders. In the UK and in other countries we need to remain vigilant and watch for symptoms. Symptoms of a haemorrhagic fever-type disease should be reported to the UK Health Security Agency via a registered medical practitioner.
Given the large number of deaths and rapid transmission how concerned should we be?
“This outbreak, as well as previous outbreaks in the DRC are of significance to the rest of the world and we need to keep a close eye and assist with diagnosis and treatment. The large number of deaths of children and young people may be worsened by malnutrition and pre-existing conditions like malaria, that could weaken the immune system.
Could the pathogen have come from a bat, and what might this tell us of the nature of the outbreak?
“There are reports of three children eating a dead bat, so people rightly ask if this outbreak could be due to a bat-related virus infection. It is unwise to seek contact with dead bats, given that they are natural reservoirs of deadly viruses. Bats carry many viruses that have previously jumped to infect humans and cause severe diseases, including viruses such as Ebola, Marburg, Nipah, Hendra severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory coronavirus (MERS-CoV) and SARS-CoV-2, which caused the COVID-19 pandemic. 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, we suffer severe disease and even death. 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.”
The current mystery illness continues to confound health officials, and further investigation is ongoing.
