EBOLA VIRUS - Ebola virus and Marburg virus

By Mayo Clinic Staff


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

Risk factors

For most people, the risk of getting Ebola or Marburg viruses (hemorrhagic fevers) is low. The risk increases if you:

Travel to Africa. You're at increased risk if you visit or work in areas where Ebola virus or Marburg virus outbreaks have occurred.

Conduct animal research. People are more likely to contract the Ebola or Marburg virus if they conduct animal research with monkeys imported from Africa or the Philippines.

Provide medical or personal care. Family members are often infected as they care for sick relatives. Medical personnel also can be infected if they don't use protective gear, such as surgical masks and gloves.

Prepare people for burial. The bodies of people who have died of Ebola or Marburg hemorrhagic fever are still contagious. Helping prepare these bodies for burial can increase your risk of developing the disease.

Complications

Both Ebola and Marburg hemorrhagic fevers lead to death for a high percentage of people who are affected. As the illness progresses, it can cause:

●  Multiple organ failure
●  Severe bleeding
●  Jaundice
●  Delirium
●  Seizures
●  Coma
●  Shock

One reason the viruses are so deadly is that they interfere with the immune system's ability to mount a defense. But scientists don't understand why some people recover from Ebola and Marburg and others don't.

For people who survive, recovery is slow. It may take months to regain weight and strength, and the viruses remain in the body for weeks. People may experience:

●  Hair loss
●  Sensory changes
●  Liver inflammation (hepatitis)
●  Weakness
●  Fatigue
●  Headaches
●  Eye inflammation
●  Testicular inflammation

Source: http://www.mayoclinic.org