What You Need to Know About Ebola as New Outbreak Reported in Guinea

Health authorities in the west African nation of Guinea have declared a new outbreak of Ebola—the first known resurgence of the disease in the region since an outbreak that killed more than 11,300 people between 2013 and 2016.

Officials reported seven cases of the disease on Sunday in the rural community of Gouéké—located in the southeast of the country—including three deaths. But what are the symptoms of Ebola and how does it spread?

Ebola virus disease (EVD) is a severe, often fatal, illness that affects humans and other primates, according to the World Health Organization (WHO).

The virus, which was first discovered in central Africa in 1976, is transmitted from wild animals—such as fruit bats, porcupines and non-human primates—to people.

The pathogen can then spread among humans through direct contact with the blood, secretions, organs or other bodily fluids of infected people. Individuals can also catch the virus from contaminated surfaces and materials, such as bedding and clothing.

Since its discovery, several confirmed outbreaks have been documented, primarily in sub-Saharan Africa.

The average fatality rate from EVD is high—hovering around 50 percent—although rates from as low as 25 percent to as high as 90 percent have been reported during past outbreaks.

The symptoms of EVD include fever, fatigue, muscle, pain, headache, and sore throat. These can be followed by vomiting, diarrhea, rash, impaired kidney and liver function, and, sometimes, internal and external bleeding.

Symptoms can appear suddenly, developing anywhere from two to 21 days after infection, according to the WHO. Infected individuals cannot transmit the virus to others until they develop symptoms.

There are two vaccines that have been licensed for use against Ebola. The first, known as Ervebo, has been approved for use by the European Medicines Agency and the U.S. Food and Drug Administration, as well as health authorities in Burundi, Central African Republic, the Democratic Republic of the Congo, Ghana, Guinea, Rwanda, Uganda and Zambia.

The vaccine has been shown to be safe and highly effective, with a study conducted in Guinea during the country's previous outbreak finding it to be 95-100 percent effective at preventing Ebola cases with symptom onset greater than 10 days after vaccination.

The Ervebo vaccine was used to immunize around 16,000 people in Guinea in 2015, as well as around 345,000 people in the Democratic Republic of the Congo during the country's 2018-2020 outbreak.

A two-dose regimen of two different shots developed by Johnson & Johnson has also been approved for use in the European Union. Other Ebola vaccines are also in development.

Because Ebola outbreaks are relatively rare and unpredictable, in addition to the fact that there are limited supplies, the Ervebo vaccine is reserved for use until outbreaks occur in order to protect individuals at highest risk of contracting the virus.

Guinea was one of the three worst-hit countries during the 2013-2016 Ebola outbreak—the largest in history.

"It's a huge concern to see the resurgence of Ebola in Guinea, a country which has already suffered so much from the disease. However, banking on the expertise and experience built during the previous outbreak, health teams in Guinea are on the move to quickly trace the path of the virus and curb further infections," Dr Matshidiso Moeti, WHO Regional Director for Africa, said in a statement.

"WHO is supporting the authorities to set up testing, contact-tracing and treatment structures and to bring the overall response to full speed."

Health worker at Ebola center in Guinea
A health worker wearing personal protective equipment works at the Ebola treatment center run by the French red cross society in Macenta, Guinea, on November 20, 2014. KENZO TRIBOUILLARD/AFP via Getty Images