Ebola viruse and Marburg virus

DEFINITION

Ebola virus and Marburg virus are related viruses that cause hemorrhagic fevers — illnesses marked by severe bleeding (hemorrhage), organ failure and, in many cases, death. Both viruses are native to Africa, where sporadic outbreaks have occurred for decades.

Ebola virus and Marburg virus live in animal hosts, and humans can contract the viruses from infected animals. After the initial transmission, the viruses can spread from person to person through contact with body fluids or contaminated needles.

No drug has been approved to treat either virus. People diagnosed with Ebola or Marburg virus receive supportive care and treatment for complications. Scientists are coming closer to developing vaccines for these deadly diseases.

The Centers for Disease Control and Prevention monitors the United States for conditions such as Ebola infection, and its labs can test for the Ebola virus. Mayo Clinic does not test for the Ebola and Marburg viruses.

CAUSES

Ebola virus has been found in African monkeys, chimps and other nonhuman primates. A milder strain of Ebola has been discovered in monkeys and pigs in the Philippines. Marburg virus has been found in monkeys, chimps and fruit bats in Africa.

Transmission from animals to humans

Experts suspect that both viruses are transmitted to humans through an infected animal’s bodily fluids. Examples include:

• Blood. Butchering or eating infected animals can spread the viruses. Scientists who have operated on infected animals as part of their research have also contracted the virus.
• Waste products. Tourists in certain African caves and some underground mine workers have been infected with the Marburg virus, possibly through contact with the feces or urine of infected bats.

Transmission from person to person

Infected people typically don’t become contagious until they develop symptoms. Family members are often infected as they care for sick relatives or prepare the dead for burial.

Medical personnel can be infected if they don’t use protective gear, such as surgical masks and gloves. Medical centers in Africa are often so poor that they must reuse needles and syringes. Some of the worst Ebola epidemics have occurred because contaminated injection equipment wasn’t sterilized between uses.

There’s no evidence that Ebola virus or Marburg virus can be spread via insect bites.

SYMPTOMS

Signs and symptoms typically begin abruptly within five to 10 days of infection with Ebola or Marburg virus. Early signs and symptoms include:

• Fever
• Severe headache
• Joint and muscle aches
• Chills
• Weakness

Over time, symptoms become increasingly severe and may include:

• Nausea and vomiting
• Diarrhea (may be bloody)
• Red eyes
• Raised rash
• Chest pain and cough
• Stomach pain
• Severe weight loss
• Bleeding, usually from the eyes, and bruising (people near death may bleed from other orifices, such as ears, nose and rectum)
• Internal bleeding