The deadliest outbreak of Ebola in history is still ravaging countries in West Africa, particularly Guinea, Liberia and Sierra Leone. And the troubling news continues with the recent report that the head doctor treating patients with Ebola in Sierra Leone, virologist Sheik Umar Khan, has himself contracted the virus, and is now being treated by doctors from the organization Medecins Sans Frontieres (Doctors Without Borders).
The virus is notoriously deadly, causing a severe viral hemorrhagic fever, and has so far killed 60 percent of people infected by it in this West Africa outbreak. Here’s what is known about Ebola virus disease — formerly known as Ebola hemorrhagic fever — including how it’s spread and why it’s so deadly:
The first human outbreaks of Ebola on record occurred in Sudan and Zaire in 1976.
The virus is named after the Ebola River in Africa. There have been other outbreaks reported in the Democratic Republic of the Congo, the Ivory Coast, Uganda, South Sudan, Gabon, the Republic of the Congo, Guinea and Liberia, according to CNN.
There are five known strains of the virus.
They are named after their outbreak locations: Ebola-Zaire, Ebola-Sudan, Ebola-Côte d’Ivoire, Ebola-Reston, and Ebola-Bundibugyo, according to the Encyclopedia Britannica. The outbreak currently affecting West Africa is the Zaire strain of ebolavirus — which is also the most deadly of the five. Ebola-Reston, by contrast, is asymptomatic in humans.
Ebola usually kills.
Infection with the Zaire strain of Ebola causes death 80 to 90 percent of the time, according to the Encyclopedia Britannica.
Ebola can spread from person to person.
It can also be contracted if a person comes into contact with a contaminated object or even by butchering an animal infected with the virus, CNN reported. A deceased person with Ebola can still transmit the virus. Fruit bats are suspected to be a natural host of the Ebola virus, according to the World Health Organization. These bats are a popular food source throughout West Africa and so WHO officials have warned residents of outbreak areas to stop hunting and cooking with the bats.
More than a 1,000 people have been infected with Ebola in this current outbreak.
There are currently 410 suspected and confirmed cases of Ebola in Guinea, 196 suspected and confirmed cases in Liberia, and 442 suspected and confirmed cases in Sierra Leone, according to the most recent information from the Centers for Disease Control and Prevention. More than half of these cases have been fatal, with 310 suspected deaths in Guinea, 116 suspected deaths in Liberia and 206 suspected deaths in Sierra Leone.
It can be hard to diagnose early.
That’s because the very first signs of Ebola — red eyes and skin rash — can also be signs of other conditions, the CDC said. However, if there’s reason to believe a person has Ebola, there are tests that can be conducted just days after symptoms begin.
Most symptoms of Ebola occur eight to 10 days after exposure.
However, there can be signs of infection anywhere from two to 21 days after being exposed. Symptoms include fever, headache, weakness, diarrhea, vomiting, lack of appetite, stomach pain and aching muscles and joints. Infection can also cause bleeding inside and outside of the body, problems breathing and swallowing, sore throat, chest pain, red eyes, hiccups, cough and rash, according to the CDC. And yes, as Vox points out, bleeding from the eyes (as well as the nose, ears mouth and rectum) is one of the hallmark signs of Ebola.
The current outbreak has spread very rapidly.
Usually, Ebola outbreaks occur in remote areas. However, this current outbreak — which was discovered in Sierra Leone — has now been identified in 60 different locations through Liberia, Sierra Leone and Guinea, CNN reported:
Officials believe the wide footprint of this outbreak is partly because of the close proximity between the jungle where the virus was first identified and cities such as Conakry. The capital in Guinea has a population of 2 million and an international airport.
There is no cure or treatment for Ebola.
Right now, only supportive therapy is available, which includes maintaining proper fluid and electrolyte balance, maintaining blood pressure and oxygen levels, and treating complicating infections, the CDC said. While there are currently no treatments or vaccines against Ebola available for clinical use, there are some being tested.