What is Ebola hemorrhagic fever?

Definition

Ebola hemorrhagic fever is a condition caused by the Ebola virus,
leading to a serious disease that has an extremely high mortality rate. This
condition is spread by contact with the body fluids of an infected person or
animal, even after death, and can be spread in research laboratories from infected
animals. The Ebola virus, which occurs naturally in Africa, damages the lining of
blood vessels and interferes with blood clotting. Ebola hemorrhagic fever appears
in sporadic outbreaks.

Causes

Ebola hemorrhagic fever is caused by a virus from the family Filoviridae
and the genus Ebolavirus. There are five species of the virus:
Zaire, Sudan, Cote d’Ivoire,
Bundibugyo, and Reston.
Reston and Cote d’Ivoire cause relatively
mild symptoms and are usually not fatal. Zaire,
Sudan, and Bundibugyo appear to be the cause
of Ebola hemorrhagic fever. These species originate in the rain forests of Africa
and reside in an unknown host. Less commonly, these species
appear in the western Pacific in the Philippines. Although the reservoirs of the
virus are unknown, scientists theorize the virus originates in animals, possibly
bats.

Risk Factors

The main risk factor is direct contact with the body fluids of infected persons or animals. Other risk factors for Ebola hemorrhagic fever are living in or visiting areas where the Ebola virus is found, working in a laboratory where animal testing with the Ebola virus is being conducted, and caring for persons with Ebola virus infection.

Symptoms

The incubation period for Ebola hemorrhagic fever ranges from two to twenty-one days after exposure. During this time, the infected person can have joint and muscle pain, low back pain, chills, a fever, diarrhea, a headache, malaise, nausea, vomiting, and a sore throat. The disease then rapidly progresses to symptoms of bleeding from the eyes, ears, nose, mouth,and rectum; internal bleeding; depression; conjunctivitis; swelling of the genitalia; skin pain; a body-wide rash; stomach pain; seizures; coma; and delirium. About 90 percent of persons who contract Ebola hemorrhagic fever will die from the condition.

Screening and Diagnosis

There is no routine screening for Ebola hemorrhagic fever. The isolated geographic areas in which the disease occurs affects diagnosis, which is often delayed because of a lack of medical care or because of inadequate medical care. Diagnosis is achieved through symptoms and blood tests, including complete blood count, blood electrolytes, blood coagulation tests, and identification of the virus or antibodies to the virus. If a person is infected, his or her blood cell counts will be low, electrolytes will be decreased, and blood coagulation rate will be decreased. Testing for the virus or its antibodies is performed using antigen-capture enzyme-linked immunosorbent assay or by polymerase chain reaction.

Treatment and Therapy

There is no cure for Ebola hemorrhagic fever. Existing antiviral medications do not seem to be effective against this virus. The treatment for Ebola hemorrhagic fever is intensive and supportive care. This care includes intravenous fluids and blood transfusions; replacing electrolytes and blood coagulation factors; oxygen; maintaining blood pressure with medications; and treating complications, such as infections.

The types of treatments used are based on the symptoms and blood tests of the infected person. The transfusion of blood from Ebola fever survivors to persons with Ebola has been tried. Because the survivor blood has antibodies to the virus, experts believe this blood could assist the infected person in fighting the disease. There is limited data, however, on the effectiveness of this treatment.

Prevention and Outcomes

The only way to prevent Ebola hemorrhagic fever is to avoid places where the
virus is known to occur. This includes Africa, the Philippines, and laboratories
that perform animal testing with viruses. Because the reservoir of the Ebola virus
is not known, there is no way to eliminate the virus. Caretakers of infected
persons and workers in viral-testing animal laboratories should always wear
personal protective clothing, such as a gown, gloves, goggles, and a facial
mask.

Testing is underway to develop a vaccine against the Ebola virus. Most of the testing of this vaccine, however, has been performed on animals.

Education of persons living in areas where the Ebola virus resides can limit the spread of the disease. This education consists of teaching villagers to avoid unprotected contact with persons who have or had the disease, whether living or dead. It also includes teaching villagers to avoid unprotected contact with dead animals in cases in which the cause of death is unknown.

Bibliography

Francesconi, Paolo, et al. “Ebola Hemorrhagic Fever Transmission.” Emerging Infectious Diseases 9.11 (2003). Print.

Hewlitt, Barry S., and Bonnie L. Hewitt. Ebola, Culture, and Politics: The Anthropology of an Emerging Disease. Belmont: Thomson, 2008. Print.

Knipe, David M., and Peter M. Howley, eds. Fields’ Virology. 7th ed. Philadelphia: Wolters, 2013. Print.

Palermo, Elizabeth. "Ebola vs. Hemorrhagic Fever: What's the Difference?" LiveScience. Purch, 9 Oct. 2014. Web. 31 Dec. 2015.

Peters, C. J., and J. W. LeDuc. “An Introduction to Ebola: The Virus and the Disease.” Journal of Infectious Diseases 179, supp. 1 (1999): ix-xvi. Print.

Singh, Sunit K., and Daniel Ruzek. Viral Hemorrhagic Fevers. Boca Raton: CRC, 2014. Print.