Ebola Virus Disease

 

Overview

The Ebola virus can cause Ebola virus disease, a severe, often fatal disease that has caused several destructive outbreaks in Africa in the last century.

Ebola is highly infectious. It can spread rapidly and has a high death rate, particularly in areas with overstretched health care systems — such as parts of West Africa, in which the 2014 outbreak took thousands of lives.

Primates like African chimps can carry the virus, and outbreaks usually begin when a human contracts the virus through contact with one. In the Philippines, scientists have discovered a less severe strain of Ebola in some monkeys and pigs. 

Symptoms

Ebola Virus Ecology and TransmissionSymptoms of Ebola virus disease usually develop within 21 days of infection with the virus. The average, though, is between eight and 10 days, reports the Centers for Disease Control and Prevention (CDC).

Symptoms of Ebola virus disease include a fever higher than 101.5 degrees Fahrenheit, muscle and head pain, weakness, nausea, bruising and unexplained bleeding (called hemorrhaging).

Bleeding from Ebola virus disease typically happens once the disease has advanced. The bleeding can be internal, external or both.

Diagnosis

Especially during an outbreak, doctors will conduct blood tests on patients who have Ebola symptoms to confirm or rule out Ebola virus disease.

But making the diagnosis can be difficult with patients who may be within their first few days of infection. Early symptoms — like fever and nausea — are common to many diseases, and on the scale of all diseases, Ebola virus disease is relatively rare.

If a patient has been in an area with a current Ebola outbreak or has encountered an infected person or animal, doctors will typically monitor that patient for symptoms and place him or her in isolation until the results of a blood test clear or confirm Ebola. 

Treatments

As of October 2014, there is no treatment for Ebola that is approved by the US Food and Drug Administration (FDA). Because of the lack of viable medications to treat the virus, doctors usually try to treat the symptoms.

Ebola patients are often placed in intensive care. There, doctors take several measures to increase the patients’ chances of survival. These measures include providing fluids, stabilizing oxygen and blood pressure levels, replacing lost blood and treating any other infections that arise.

Other medicines used to fight viral infections do not appear to have much effect on Ebola.

The 2014 West African Ebola outbreak sparked a surge in Ebola treatment research. Researchers and pharmaceutical companies, as of October 2014, had several treatments under review, but none were FDA-approved.

Causes

The Ebola virus can cause Ebola virus disease. The virus has been found in primates like monkeys and chimpanzees. Transmission from animals to humans usually occurs when humans eat infected animals.

Once the virus has transferred to humans, it can only be spread through contact with infected bodily fluids. Humans are thought not to be contagious until they show symptoms.

Ebola is not spread through the air or by insects like mosquitoes.

Living With

On average, Ebola virus disease is fatal in 50 percent of cases, according to the World Health Organization (WHO). However, the fatality rate varies by outbreak — it’s been as high as 90 percent and as low as 25 percent.

Patients who survive an Ebola infection have reported side effects like hair loss and joint pain.

Ebola survivors develop antibodies to the virus, which means they are less likely to catch it again. These antibodies may last up to 10 years.

Whether Ebola survivors are susceptible to other strains of the virus is unknown.

Getting Help

If you believe you have been exposed to the Ebola virus, do not wait for symptoms to develop — seek emergency medical care immediately.

If you have recently traveled to Africa and develop symptoms of Ebola virus disease, contact a medical professional immediately.

Related Information

If you are traveling in an area with a current Ebola outbreak, take precautions against the disease. Preventive measures include frequent hand washing and avoiding bodily fluids and close contact with people who might be infected. Avoid handling objects or touching surfaces that might have come into contact with another person’s blood.

Monitor your health closely for the first 21 days after you return from an area where you could have been exposed to Ebola. If you notice any symptoms developing, seek immediate medical care.

References
Centers for Disease Control and Prevention, “Ebola (Ebola Virus Disease)”
http://www.cdc.gov/vhf/ebola/
MedlinePlus, “Ebola hemorrhagic fever”
http://www.nlm.nih.gov/medlineplus/ency/article/001339.htm
Mayo Clinic, “Ebola virus and Marburg virus”
http://www.mayoclinic.org/diseases-conditions/ebola-virus/basics/definition/con-20031241
World Health Organization, “Ebola virus disease”
http://www.who.int/mediacentre/factsheets/fs103/en/