An Overview of Ebola

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Ebola is a rare but deadly virus almost exclusively found in Central and Western African countries. Roughly half of those who get Ebola virus disease (EVD) die from it. Those who survive can still experience weakness, pain, diarrhea, and unexplained bleeding. Spread by direct contact with body fluids of a person or animal who has been infected, over two dozen outbreaks have been reported, affecting over 31,000 people. No cure currently exists for EVD, but an investigational vaccine against the virus could be licensed as early as 2018.

History

EVD was first discovered in 1976, when the Ebola virus caused two deadly—and completely separate—outbreaks in what are now known as South Sudan and the Democratic Republic of Congo. Researchers have since studied a wide range of plants and animals to try to identify how the virus enters human populations, but they have yet to pinpoint what virologists call the "natural reservoir," or original host, of the virus. The most likely candidate so far is the African fruit bat, though there isn't enough evidence to say conclusively that the animals play a major role in Ebola transmission.

Symptoms

Symptoms typically start to show up about eight to 10 days after a person is exposed to the Ebola virus, though they could appear anywhere from two to 21 days. Early symptoms look a lot like other, more common illnesses like malaria and flu, but they can quickly escalate, killing some people within one to two weeks. Symptoms of EVD include:

  • Fever
  • Fatigue
  • Headache
  • Loss of appetite
  • Muscle pain or weakness
  • Sore throat
  • Diarrhea and vomiting
  • Abdominal pain
  • Unexplained bleeding or bruising, such as bleeding from the gums or having blood in your stool
  • Seizures
  • Coma

It should be noted that not everyone with EVD has all of these symptoms. Bleeding, for example, doesn't happen in all cases and typically only occurs when the illness is at its peak. If you have been in contact with someone who has been diagnosed with Ebola virus disease and you start to feel ill, call your doctor right away. 

Causes

EVD is caused by Ebola virus. There are five different types of Ebola virus affecting primates, but only four can cause EVD in people. During Ebola outbreaks, the virus is typically spread from person to person in a few different ways.

Human Transmission Risks

  • Coming into direct contact (through broken skin or openings like eyes or mouth) with body fluids, including blood, semen, sweat, saliva, feces, breast milk, and vomit. This includes touching objects (ex. syringes or bed sheets) that have been contaminated with the body fluids of someone actively sick or who died from EVD.
  • Having anal, oral, or vaginal sex with a man who has recovered from EVD. Researchers are still trying to figure out how long the virus can stay in semen and other body fluids, but some studies show fluids test positive for Ebola virus 9+ months after the person was infected.

In some instances, the Ebola virus can also be passed onto humans after coming into contact with infected apes, monkeys, or fruit bats.

While some studies have detected Ebola virus in domesticated animals like cats and dogs, there's no evidence to suggest those animals can become sick with EVD or spread the virus to other animals, including humans. The one exception is pigs, which can get infected and potentially spread the virus, though it doesn't appear pigs can spread the infection to people.

How Healthcare Workers Protect Themselves from Ebola

Diagnosis

EVD can be tough to diagnose early because it's so rare, and initial symptoms—like fever and headache—can look a lot like other, more common infections like malaria or dengue fever. The only way to know for sure someone has EVD is by testing blood samples.

Health professionals will typically only test for EVD if you meet both of the following criteria:

  • Have symptoms of the disease
  • You were possibly exposed to the virus within three weeks before the symptoms started to appear

The first step to diagnosing EVD is a physical exam, where providers look for Ebola-compatible symptoms. During the exam, they'll also ask if you've traveled to places where Ebola is more common, such as Central or Western Africa, or if you've had physical contact (including sexual contact) with someone who is infected or has been recently.

If you check both of those boxes, health professionals will likely isolate you and call public health authorities while tests are being run. To run the tests, providers take a sample of your blood to look for either the genetic material of the Ebola virus or antibodies against it.

Even if you have symptoms, the virus might not be detectable in your blood for three days. During that time you would continue to be isolated and tested for other pathogens (ex. malaria) until a diagnosis can be made.

Treatment

Currently, no cure exists for EVD. While some viruses can be treated successfully with antiviral drugs, no such medications exist to combat Ebola virus. The only way to treat EVD is to manage symptoms while the disease takes its course. This includes:

  • Taking in plenty of fluids, including some with electrolytes, either by mouth or intravenously to prevent or treat hydration
  • Providing oxygen therapy to maintain oxygen levels
  • Administering medications to reduce fever, pain, or nausea, or to support blood pressure
  • Giving medications to treat co-infections (such as malaria)

While these methods won't rid someone of EVD, they can significantly improve their chances of survival if started during the earliest stages of the disease.

Health providers caring for someone with Ebola are advised to take extra precautions to prevent the spread of Ebola virus in clinical settings. This includes covering their clothes, hands, eyes, nose, and mouth, and being extra careful when handling any medical waste. They'll also attempt to track down anyone else who might have been infected to reduce the chances of an outbreak.

Ebola Vaccine

Currently, no Ebola vaccine has been approved for use in the United States. But an experimental vaccine, known as rVSV-ZEBOV, has been successful in preventing Ebola in humans during trials conducted in more than 16,000 volunteers around the world. The vaccine doesn't include the Ebola virus itself. It's made using an animal virus called vesicular stomatitis virus that has been genetically engineered to have a protein from the Zaire Ebola virus strain.

While the vaccine has yet to be formally approved, the World Health Organization and other regulatory agencies have recommended it be used in the event of an outbreak of the Zaire strain. Some 300,000 doses are on standby in the event an outbreak happens before the Food and Drug Administration can approve the new vaccine, which current signs indicate could be as early as 2018.

The Reality Surrounding the Ebola Vaccine

Coping

EVD can be a painful and frightening disease, and supportive care is crucial. But in addition to the physical stress, many with EVD are placed in medical isolation, meaning they aren't allowed to leave a particular area and interactions with loved ones are limited. This type of confinement can leave some feeling bored, restless, and isolated. To help limit the psychological toll medical confinement can have on a person, you can:

  • Talk to the health care providers treating you about why isolation is necessary for you and who it's protecting.
  • Ask loved ones to bring you some of your favorite books, movies, or music and talk with them frequently over the phone via video chats (if permitted by the facility).
  • Seek additional counseling or consult a trained mental health professional if the stress is becoming too much or if you're starting to feel your mood spiral.

Even after recovering from EVD, you can still have lingering health issues that can affect your quality of life. These include feeling tired, experiencing headaches or muscle pain, vision problems, weight gain, or loss of appetite. Less common complications can be even more serious, including memory loss, hearing problems, and mental health challenges such as post-traumatic stress disorder. Talk to your doctor if you experience any of these issues.

Once you recover from an Ebola infection, the virus could linger in your body for months, especially in the testes, nervous system, and interior of the eyes. It can also show up in semen even after your symptoms have gone away. Before engaging in sexual activity, discuss what precautions you should take (if any) with a health care provider to prevent passing Ebola onto loved ones.

In some countries, being an Ebola survivor can come with a lot of stigma, making it hard for those who do recover to find jobs or participate in their communities. For its part, the World Health Organization is working to educate health professionals on how to care for EVD survivors, including psychosocial services like counseling.

A Word From Verywell

While EVD is a dangerous and often deadly disease, it is extremely rare in the United States and other countries outside of Africa. It also isn't spread through casual contact like holding someone's hand or sitting near them in a room, even if the person has been diagnosed with Ebola. That said, if you’ve been in a place where an Ebola outbreak has occurred and/or came in direct contact with the fluids of someone with the disease, call a doctor right away if you start having flu-like symptoms.

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