(World Health Organization)
• Ebola disease is a severe, often fatal illness in humans.
• Three different viruses are known to cause large Ebola disease outbreaks: Ebola virus, Sudan virus and Bundibugyo virus.
• The average Ebola disease case fatality rate is around 50%. Case fatality rates have varied from 25–90% in past outbreaks.
• Early intensive supportive care with rehydration and the treatment of symptoms improves survival.
• Approved vaccines and treatments are only available for one of the viruses (Ebola virus) and are under development for the others.
• Outbreak control relies on a package of interventions including intensive supportive care of patients, infection prevention and control, disease surveillance and contact tracing, laboratory services, safe and dignified burials, vaccination if relevant, and social mobilization.
(Richard Preston, New Yorker, 10-19-91)
Lessons from an outbreak of Ebola. Note the year: 1991.
Like all viruses, Ebola and its cousin Marburg are parasites. They can copy themselves only inside a cell. Viruses need to use a cell’s equipment to reproduce.
(Richard Preston, New Yorker, 10-20-2014)
As an epidemic widens, the virus is mutating. Geneticists are racing to keep up.
• Is Ebola Evolving Into a Deadlier Virus?
(Richard Preston, New Yorker, 8-7-19)
The virus that has infected thousands in the Democratic Republic of the Congo has been replicating itself every eighteen hours for more than a year.
Right now, there may be around six hundred people in eastern Congo who have Kivu Ebola particles replicating in their bodies. As Ebola re-creates itself, many of the resulting particles are deformed duds and can’t replicate further. The ones that can copy themselves are infective. The Kivu swarm, with its three new lineages of Ebola, may amount to about one or two quadrillion infective particles of the virus. If these particles were collected in one place, they would fill three teaspoons and would weigh about fifteen grams.
That small space contains numberless genetic possibilities. The longer the outbreak is allowed to continue, the greater the chances that Ebola will mutate, get better at spreading in humans, and vastly enlarge its circle of victims.
• Ebola outbreak may be spreading faster than first thought, WHO doctor warns
(BBC News, video, 3.37 minutes, 5-20-26)
• WHO chief concerned over ‘scale and speed’ of Ebola outbreak as Congo reports 134 dead
(AP News, via MedPage Today, 5-19-26)
The director-general of the World Health Organization voiced concerns about the "scale and speed" of an outbreak of a rare Ebola variant in the Congo, where authorities reported a sharp rise to at least 131 suspected deaths and more than 500 suspected cases.
• Ebola Fast Facts (CNN)
• With no approved vaccine for Ebola outbreak, experts weigh testing a long shot
(Helen Branswell, STAT News, 5-18-26)
While there is no vaccine for this type of Ebola, animal study suggests Merck’s Ervebo, designed for another strain of the virus, might offer some protection.
• Flawed tests and funerals allowed Ebola to spread undetected, sources say
(Reuters, 5-18-26)
Local funeral practices helped the virus spread before any alarm was raised, diagnostic tests in a local laboratory were calibrated for the wrong strain of Ebola, and samples sent to Kinshasa were not stored or shipped properly, the officials said.
Experts say the resulting delays risk hobbling efforts to contain the outbreak, which the World Health Organization at the weekend declared a public health emergency of international concern.
"It's just a scattered mess right now. I don't think we have anything close to a real idea of how many cases there are," said Craig Spencer, an emergency physician and public health professor at Brown University.
• Ebola virus Background on ebola virus, in section on medical mysteries.
• Ebola vaccine