What Is Ebola?

Ebola, or Ebola virus disease (EVD), is a serious infection that occurs most often in Central and Western African countries. It begins with a fever, headache, and other common symptoms of infection. These are followed by more severe symptoms such as impaired liver and kidney function and bleeding inside and outside of the body.

The virus is spread through direct contact with body fluids of a person or animal who's infected with the virus. It can only be diagnosed with a blood test.

Roughly half of people with EVD die from it. Those who survive often have lingering complications. Ebola can be challenging to deal with. However, there are two medications for treating it and a vaccine to help prevent it.

This article is an overview of Ebola virus infection. It discusses the symptoms and causes of EVD and explains how the infection is diagnosed and treated.

Ebola Symptoms and Complications

A person can start feeling sick within two to 21 days after becoming infected with the Ebola virus. Most often, symptoms of EVD appear within eight to 10 days of exposure. People who recover from Ebola often have long-term complications.

Symptoms

At first, EVD looks much like any infection, such as the flu. Early symptoms include:

• Fever
• Fatigue
• Headache
• Loss of appetite
• Muscle pain or weakness
• Sore throat
• Abdominal pain
• Diarrhea and vomiting
  

The disease can quickly get worse and may cause:

• External bleeding—from the gums, eyes, nose, and ears
• Internal bleeding, which may show up in the stool
• Unexplained bruising
• Organ failure
• Seizures
• Coma

Complications

People who recover from EVD often continue to have health issues such as fatigue, headaches, muscle pain, vision problems, weight gain, and loss of appetite.

More serious complications of Ebola include memory loss, hearing problems, and post-traumatic stress disorder.

What's more, even after Ebola symptoms clear up, the virus can stay in the body for months. It tends to stay in the nervous system, inside the eyes, and, in males, the testicles—the pair of organs that produce sperm.

Causes

EVD is caused by the Ebola virus. There are four species of Ebola virus that can infect humans. The most deadly one is the Zaire ebolavirus.

During Ebola outbreaks, the virus typically spreads from person to person in a few different ways:

• Direct contact with body fluids, including blood, semen, sweat, saliva, feces, breast milk, and vomit, through broken skin or openings like eyes or mouth
• Touching objects that may have been contaminated by an Ebola patient, such as syringes or bed sheets
• Anal, oral, or vaginal sex with a male who's had EVD

There's evidence the Ebola virus may remain in body fluids for nine months or more.

It's also possible the Ebola virus can be passed to humans by infected apes, monkeys, or fruit bats.

Diagnosis

Because at first Ebola looks like a garden-variety infection, it often isn't diagnosed until it becomes advanced and symptoms such as liver or kidney problems or bleeding develop.

EVD is diagnosed with a blood test. Healthcare providers typically test for EVD when a person has both:

• Symptoms of the disease
• Exposure to the virus within three weeks before symptoms appeared

When someone meets both criteria, a sample of their blood will be taken and examined in a lab to look for the genetic material of the Ebola virus or signs of antibodies against it.

Meanwhile, they likely will be isolated and the possible infection will be reported to public health authorities. Because it can take up to three days for the Ebola virus to show up in blood, even when there are obvious symptoms of infection, people suspected of having Ebola must stay isolated and their blood tested for other possible infections, such as malaria, until a diagnosis is made.

Treatment and Prevention

For many years after Ebola was discovered, the only way to treat it was to manage symptoms while the disease ran its course. While this kind of care is still important, there are now two medications for treating EVD, as well as a vaccine to prevent it.

Managing Symptoms

Treatment for EVD often includes:

• Increasing fluids and electrolytes, which may require intravenous fluids (through a needle in the skin) if a person isn't able to drink enough to stay hydrated
• Oxygen therapy
• Medications to treat symptoms such as fever, pain, nausea, and high blood pressure
• Medication to treat co-infections (such as malaria)

The sooner these measures are taken, the greater the chances a person will survive the infection.

Medication

In 2020, the Food and Drug Administration (FDA) approved two medications for treating Zaire ebolavirus:

• Ebanga (ansuvimab-zykl)
• Inmazeb (atoltivimab, maftivimab, and odesivimab-ebgn)

Both use monoclonal antibodies to treat the infection. Monoclonal antibodies are man-made proteins that resemble the antibodies produced naturally in the immune system. Because they're produced in a lab, they can be made to directly target specific infections.

Prevention

There are two licensed Ebola vaccines. Ervebo (Ebola Zaire vaccine) was approved by the FDA in 2019. It is a one-shot vaccine that is designed to be used during Ebola outbreaks to protect people at high risk of infection—an approach known as "ring vaccination."

People who would be eligible to receive Ervebo during an outbreak include:

• Those who have had close contact with someone infected with Ebola or their body fluids, bed linens, or clothing in the last 21 days
• Neighbors, close or extended family members, or other household members of someone who has been infected with Ebola
• Health care workers and frontline workers who may be in contact with Ebola patients

The other Ebola vaccine is given in two doses: Zabdeno (Ad26.ZEBOV) followed by Mvabea (MVA-BN-Filo). It is approved for babies and adults 1 year and older. It is not yet available but is being reviewed by the World Health Organization's Strategic Advisory Group of Experts (SAGE) on Immunization,

Summary

Ebola viral disease (EVD) is an infection that is most common in Africa. At first it can resemble a less serious infection, but as it progresses it can cause liver and kidney problems, bleeding, and, in about half of cases, death. Ebola is diagnosed with a blood test. Treatment involves managing symptoms and antiviral medication. Two vaccines have been licensed to target the most deadly species of the virus, Zaire ebolavirus, with others in the works.

A Word From Verywell

Ebola is extremely rare in the United States and other countries outside of Africa. Where it is common, however, it carries a lot of stigma. People who recover from EVD may have trouble finding work or be shunned by their communities. To help, the World Health Organization is working to educate health professionals on how to care for EVD survivors, including psychosocial services like counseling.