Almost three years into the COVID-19 pandemic, as global monkeypox cases rose precipitously and are now on a continual decline, the public may be tired of hearing about epidemic diseases — especially in distant places. But the recent Ebola outbreak in Uganda is deeply concerning, and demands close international attention.
On September 20, 2022, Ugandan health officials declared an outbreak of Ebola. First detected in Mubende, the disease has since spread to four other districts and the populous capital Kampala. As of October 26, the disease had killed 30 and infected 109 people — the largest outbreak in 20 years in Uganda – but the actual prevalence is likely higher. Uganda’s neighbors are on high alert since the World Health Organization (WHO) assessed the risk of cross-border spread to be high. Uganda’s President Museveni has since ordered a lockdown and three-week curfew for the two affected districts. One WHO official now warns that the outbreak is rapidly evolving.
Ebola is a horrible disease. A hemorrhagic fever, Ebola can induce intense weakness, body aches, fatigue, vomiting, and diarrhea, with severe internal bleeding leading to death in 50% of cases on average. Once introduced into human populations, the virus spreads via contact with blood or other bodily fluids. Health workers are most at risk, as well as other close contacts, such as family members.
Ebola is highly contagious, and outbreaks left unchecked can quickly spiral out of control. The West Africa epidemic from 2014 to 2016 killed over 11,000 people. After months of inaction, WHO declared that outbreak to be a public health emergency of international concern and made that determination again in 2019 when the disease emerged in the Democratic Republic of the Congo.
Following the West African Ebola outbreak, the world rushed to develop vaccines and treatments for Ebola that target the Zaire species of the virus, which transformed the fight against Ebola. But those tools are ineffective against the species currently circulating in Uganda — Sudan ebolavirus — for which there are also no licensed vaccines or treatments. Despite Sudan ebolavirus being ranked by experts in 2016 as the top target for vaccine research and development based on feasibility and need, manufactures have had limited incentive to design and produce vaccines at the quantities needed for an outbreak response.
Now, much like in early 2020 for COVID-19, the race is on to test and approve an effective vaccine against Sudan ebolavirus. Two candidates are being tested — the one further ahead is a GSK single-dose vaccine licensed to the Sabin Vaccine Institute and developed in part by the National Institute of Allergy and Infectious Diseases, while the Coalition for Epidemic Preparedness Innovations is working to source a manufacturer. A second single-shot candidate developed by the University of Oxford is close behind, and the university has contracted with India’s Serum Institute to manufacture at least 20,000 doses by the end of November. What’s more, the pharmaceutical giant Merck has acknowledged it has an experimental vaccine that targets Sudan ebolavirus, which is yet to be tested but showed early promise, and of which it has large volumes.
WHO’s proposed clinical trial uses a ring vaccination strategy successfully deployed to test a vaccine against the Zaire Ebola species. But even if clinical trials succeed, the challenge remains to produce doses fast enough to respond to the crisis and ensure they are delivered to those at highest risk. First doses should be prioritized for healthcare workers and close contacts of people with the virus. And should the outbreak spread internationally, nations cannot hoard lifesaving technologies and repeat those pronounced inequities of the COVID-19 response.
Until vaccines and treatments are available, Uganda relies on traditional infection control tools of hygiene, surveillance, contact tracing, isolation and quarantine, a sufficient, qualified health workforce, and adequate supplies of personal protective equipment (PPE). But Uganda’s resources are limited, prompting its health minister to call upon other countries for help in procuring enough PPE. And its health workforce was already strained from dual crises of COVID-19 and malaria.
Meanwhile, the United States is protecting itself. The Centers for Disease Control and Prevention (CDC) has ordered all incoming passengers from Uganda be diverted to five airports and screened — an approach the European Union CDC has recommended against. No cases of Ebola connected with this outbreak have been reported in the United States.
The Uganda Ebola outbreak tells an all-too-familiar story of neglect of diseases largely found in low- and middle-income countries. And when outbreaks do threaten to spill over to high-income countries, we protect ourselves first and foremost. Research into diseases, like Ebola, that periodically emerge in Africa or other lower-income regions should be prioritized. Countries shouldn’t have to wait until outbreaks cause deep human and social suffering before research begins. At the same time, many low resource countries lack the basic health infrastructure to deal with multiple health threats simultaneously — like COVID-19, monkeypox, and measles, along with hemorrhagic fevers.
What the United States and other high-income countries should do now is urgently supply Uganda with medical and human resources needed to fill gaps in its emergency response. Meanwhile, research funding should focus on diseases that we know will emerge periodically and for which we should have vaccines and treatments.
Whether out of national self-interest, humanitarian inclination, or legal obligation to cooperate, stopping outbreaks wherever they occur is not just a good idea, it is imperative. We know this to be true from the ever more frequent outbreaks, epidemics, and pandemics the world has recently experienced. These potentially catastrophic health threats are only likely to accelerate further as we cut down forests, build congested cities, and wreak havoc on this planet.