Cordon sanitaire in two Ebola-affected districts

Last week, there was a substantial escalation in the fight against Ebola. The president of Uganda, Yoweri Museveni, announced a 21 day cordon sanitaire (or “cordon” for short) in two of the five affected provinces. People are not allowed to move in or out of the cordoned areas except on official business or to deliver cargo. Public transportation and transportation for hire are closed, as are religious services, gyms, bars and other public spaces. There are currently 64 confirmed cases of the virus, and 25 confirmed deaths (44 deaths total, if probable deaths are included in the count).

cor·don sa·ni·taire: a guarded line preventing anyone from leaving an area infected by a disease and thus spreading it. (Oxford Languages)

Until recently, cordons were rarely used as tools to slow the spread of disease, at least in modern times. Liberia and Sierra Leone instituted cordons during the 2014 Ebola outbreak, but not until the outbreak was much larger than what is currently observed in Uganda. During the COVID-19 pandemic, cordons and other social distancing measures (“lockdowns”) became common in a bid to prevent health systems from becoming overwhelmed as the world waited for vaccines and diagnostic tests. Most countries have moved on from such measures, with the exception of China. (There are other examples of modern lockdowns, but they are uncommon. Just recently, a post in the disease outbreak news service ProMED reported that a town in Tibet was under lockdown after two deaths from pneumonic plague, a serious bacterial infection.)

The strict measures are an indication of how aggressively Uganda is responding to the outbreak. Several recent developments underscore how precarious the situation is. At least two cases were recently reported in Kampala; a husband and wife traveled to the capital city from Mubende, the most affected region. Although local transmission in Kampala has not been reported, it is a worrisome development in the country’s largest city. Moreover, yesterday the World Health Organization reported that the Ministry of Health is investigating eight cases that have no epidemiological link to other confirmed cases. If true, this could indicate smoldering chains of transmission that have not yet been found by public health authorities.

In more positive news, the Ministry of Health reported a 97% contact tracing follow up rate on October 14, meaning that officials were able to check in with almost all the 873 people who are in quarantine. A high follow-up rate is critical to rapidly identifying, isolating, and treating people who develop infection after exposure. There have also been improvements in testing. On the testing front, the mobile laboratory that has been stationed in Mubende returned all results within 6 hours, likely a substantial improvement over when samples needed to be transported to Kampala for testing. The Ministry reports that the mobile laboratory is adequately stocked.

There are no approved vaccines or treatments for this outbreak, which is caused by Sudan virus. (There are options for Zaire ebolavirus, which is responsible for most outbreaks in the Democratic Republic of Congo and the 2014 outbreak in West Africa.) However, there are several candidate products that may be available for certain uses soon. The World Health Organization says it will be able to deploy two candidate vaccines, one from the Sabin Vaccine Institute and one from Oxford University, in about two weeks. These vaccines will be used in a clinical trial setting so that data can be collected on their efficacy.

Candidate treatments are also on their way. The United States is sending doses of remdesivir, a broad-spectrum antiviral, and a candidate antibody drug by the company that developed Zmapp, a treatment for Zaire ebolavirus. These products will be used to treat people who are already infected, and possibly as post-exposure prophylaxis for people who have had an exposure that puts them at high risk of becoming infected. I expect the number of doses available is very limited.

Other notes

• Influenza is beginning to pick up steam in the United States. I took my family to get our flu vaccines recently and I got my bivalent covid booster last month. Please check to see if you are due for either or both of these vaccines and remind your loved ones (especially older adults) to get theirs as well.

• I am also still seeing multiple reports of RSV and other respiratory illnesses hitting kids hard. Particularly families with young children should consider taking extra precautions to prevent infections. (More from me on that here and here.)

• The WHO’s Emergency Committee on monkeypox met today. The committee meets at least every three months to advise the WHO Director-General on whether the monkeypox epidemic still constitutes a Public Health Emergency of International Concern. Their recommendation, and the Director-General’s decision, have not yet been announced.

• I recently had the honor of being selected for Vox’s Future Perfect list of “scientists, thinkers, scholars, writers and activists building a more perfect future.” This Substack is linked in the write-up—thank you, subscribers, for your support! You can find the full list of honorees here.

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The "common" viruses for our kids may be back