Viral hemorrhagic fevers (VHFs)
Interim Guidance about Ebola Virus Infection for U.S. Citizens Living Abroad
Overview of Ebola Hemorrhagic Fever
Ebola hemorrhagic fever is a severe, often-fatal disease in humans and nonhuman primates (monkeys, gorillas, and chimpanzees) that has appeared sporadically since its initial recognition in 1976. The disease is caused by infection with Ebola virus, named after a river in the Democratic Republic of the Congo (formerly Zaire) in Africa, where it was first recognized. The virus is one of two members of a family of RNA viruses called the Filoviridae. There are five identified species of Ebola virus. Four of the five have caused disease in humans: Zaire ebolavirus, Sudan ebolavirus, Cote d'Ivoire ebolavirus, and Bundibugyo ebolavirus. The fifth, Reston ebolavirus, has caused disease in nonhuman primates and was associated with disease in pigs, but no disease has been described in humans.
The virus has the potential to spread from person to person, especially among health-care staff and family members who care for patients with Ebola VHF. After an incubation period of 2-21 days, the disease usually presents with sudden fever, chills, and muscle aches. Around the fifth day after onset of symptoms, a skin rash can occur. Nausea, vomiting, chest pain, a sore throat, abdominal pain, and diarrhea may follow. Symptoms become increasingly severe and may include jaundice, severe weight loss, mental confusion, shock, and multi-organ failure.
The virus is believed to be transmitted from an unknown animal host to humans. Humans can infect other humans through contact with blood or body fluids (e.g., saliva, urine). People who have close contact with a human or nonhuman primate infected with the virus are also at risk. Such persons include laboratory or quarantine facility workers who handle nonhuman primates that have been associated with the disease. In addition, hospital staff and family members who care for patients with the disease are at risk if they do not use proper barrier nursing techniques. These precautions include wearing protective gowns, gloves, and masks, in addition to wearing eye protection (e.g., eye glasses) or a face shield.
The likelihood of contracting any VHF, including Ebola, is considered extremely low unless there has been direct contact with the body fluids of symptomatic infected persons or animals, or objects that have been contaminated with body fluids. The cause of fever in persons who have traveled or live in areas where VHF is present is more likely to be a common infectious disease, but such persons should be evaluated by a health-care provider to be sure.
Persons living in areas affected by Ebola hemorrhagic fever should observe the following measures to help avoid illness.
- As with other infectious illnesses, one of the most important preventive practices is careful and frequent handwashing. Cleaning your hands often, using soap and water (or waterless alcohol-based hand rubs when soap is not available and hands are not visibly soiled with blood or body fluids), removes potentially infectious materials from your skin and helps prevent disease transmission. When wearing gloves, wash the gloves with soap and water before removing them, and then wash your hands.
- Avoid contact with dead animals, especially primates.
- Do not eat "bushmeat" (wild animals, including primates, sold for consumption as food in local markets)
- To minimize the possibility of infection, observe barrier techniques when in close contact with a person or an animal suspected of having Ebola virus infection. These precautions include wearing protective gowns, gloves, and masks, in addition to eye protection (e.g., eye glasses) or a face shield. Sterilization and proper disposal of needles and equipment, and proper disposal of patient excretions are also important to prevent the spread of infection.
If you think you have Ebola virus infection or symptoms compatible with Ebola VHF
If you or your family members become ill with fever or develop other symptoms such as chills, muscle aches, nausea, vomiting, or rashes, visit a health-care provider immediately. The nearest U.S. Embassy or Consular Office can help you find a health-care provider in the area. You are encouraged to identify these resources in advance. When traveling to a health-care provider, limit your contact with others. All other travel should be avoided.
After your return
Persons returning from an affected area but have not had direct contact with the body fluids of symptomatic infected persons or animals, or objects that have been contaminated with body fluids, should monitor their health for 10 days. Those with a potential exposure should monitor their health for 21 days post exposure. Regardless, any traveler who becomes ill while traveling, even if only a fever, should consult a health-care provider immediately and tell him or her about their recent travel and potential contacts. Tell the provider about your symptoms prior to going to the office or emergency room so arrangements can be made, if necessary, to prevent transmission to others in the health-care setting.
- For more information about CDC's health recommendations for travel to Central Africa, see: Travelers' Health - Central Africa - Region.
- For more information about Ebola hemorrhagic fever, see: Ebola Hemorrhagic Fever.
- For information about viral hemorrhagic fevers and precautionary measures, see: VHF Disease Information.