In Africa, cases of Ebola hemorrhagic fever continue to rise, but medical staff are not responding properly. Experts worry that local civil wars and the United States' withdrawal from the World Health Organization (WHO) have weakened the disease control network. Because a virus species different from previous Ebola outbreaks is responsible, there are no treatments or vaccines, let alone diagnostic kits. With patients occurring only in underdeveloped African countries, there is little economic incentive for global drugmakers to step in. A medical crisis is being further exacerbated by political and economic factors.
On the 17th (local time), the World Health Organization (WHO) declared a public health emergency of international concern (PHEIC) over the spread of Ebola virus infections in and around the Democratic Republic of the Congo and Uganda. As a vaccine- and treatment-free virus showed signs of crossing borders, the agency issued the highest-level alert and urged a joint international response.
Ebola hemorrhagic fever is a severe infectious disease caused by the Ebola virus. It involves headaches, muscle pain, fever, and generalized fatigue, later followed by systemic bleeding, and has a fatality rate of 60%. The virus was first discovered in 1976 near the Ebola River in the Democratic Republic of the Congo, giving it its name. It spreads from wild animals such as fruit bats and chimpanzees to humans, and it can also spread between people through contact with an infected person's blood or bodily fluids. This is why there are many cases of infections among medical staff.
◇No treatments, vaccines, or diagnostic kits
The WHO was notified on the 5th that Ebola had occurred in the Democratic Republic of the Congo. A health care worker showed Ebola symptoms such as fever and bleeding on Apr. 24. After that, two confirmed Ebola patients from the Democratic Republic of the Congo entered neighboring Uganda, and cases were reported there as well. Both countries officially declared outbreaks last week.
There are broadly six species in the genus Ebolavirus. Of these, four cause hemorrhagic fever in humans. The U.S. Centers for Disease Control and Prevention (CDC) said that as of the 17th, there were 336 suspected cases infected with a species called Bundibugyo and 88 related deaths. Infections with the Bundibugyo species show a fatality rate of 20% to 50%.
In particular, four medical workers died at the same hospital, suggesting the virus spread in clinical settings as before. According to the WHO, during the worst Ebola outbreak in 2014 that killed more than 11,300 people, 10% of all infections were medical staff. More than 500 medical workers died at that time.
The problem is that while there are already two vaccines for the Zaire species that caused the 2014 mass outbreak, there are no vaccines or treatments for the Bundibugyo species. The rapid diagnostic kits used in clinical settings were also designed to detect the more common Zaire species.
Raina MacIntyre, an epidemiologist at the University of New South Wales in Australia, said in the international journal Nature on the 18th, "Because the Ebola virus incubation period ranges from as short as two days to as long as 21 days, given the number of cases reported so far, it is highly likely the virus has been spreading for months."
◇Politics weaken disease control
Coincidentally, local medical workers have not been able to focus on finding Ebola patients. In areas where Ebola is spreading, health care staff are already tied up responding to other infectious diseases such as measles, mpox (Mpox), and malaria. Politics also played a part in Ebola's spread. Siouxsie Wiles, a microbiologist at the University of Auckland in New Zealand, said that because many people are fleeing civil wars locally, the virus likely circulated for a long time without being detected. Experts also believe the United States' withdrawal from the WHO early this year has dampened the WHO's ability to respond to infectious diseases. After the United States halted funding, the WHO has made deep budget cuts this year and is restructuring by reducing a quarter of its workforce.
For now, the chances of Ebola spreading worldwide are slim. Because it does not spread through the respiratory tract like COVID-19, careful identification and isolation of patients can prevent transmission. Drugmakers have not actively pursued vaccines because Ebola patients are mostly in Africa.
But the situation changes if people who traveled to infected regions or animal hosts move to other continents. The 1995 movie "Outbreak" depicts a U.S. San Francisco quarantine officer diverting a monkey smuggled from Africa, leading to scenes of people coughing up blood and dying in various places. Experts say the possibility of the virus spreading to developed countries is not zero, and because there are technologies to develop vaccines quickly, as with COVID-19 mRNA (messenger ribonucleic acid) vaccines, development of a vaccine against the Bundibugyo species of Ebola virus should be accelerated.
Fortunately, in Jan., the University of Oxford in the United Kingdom announced it had begun developing a vaccine candidate in partnership with U.S. drugmaker Moderna, which developed an mRNA COVID vaccine, to target multiple filoviruses that can cause deadly hemorrhagic fevers, including the Ebola virus and Marburg virus, simultaneously. Experts said development funding should be ramped up quickly and clinical trial regulations eased to speed vaccine development further.