Ebola virus was identified in 1976 when two outbreaks occurred simultaneously in Southern Sudan and Northern Zaire. The number of cases was 430 in Southern Sudan with 53% mortality and 550 in Northern zaire 88% mortality. Another fatal case was
reported
one year later from the same zone of zaire and small epidemic was recognized in 1979 in the same town of Sudan. Serologic tests suggested that two strains, zaire and Sudan, were different. Another strain of Ebola was isolated in 1989 during an
outbreak
of infection in cynomolgus monkeys in quarantine in Reston, Vigina, USA, The monkeys originated from the Philippines. The origin in nature and the natural history of Ebola virus remain a mystery. The exact routes by which Ebola virus may be
spread
are
not intimately known. Parenteral inoculation with contaminated material has been efficient and carries an enhanced mortality. Skin or mucous membrane contact with virus-laden materials has probably been responsible for most recognized human
infections.
Inhalation of small-particle aerosols may play a minor role, but this route is not established. Ebola virus hemorrhagic fevers have an incubation period of 7 days(range 2-21 days) and begin with abrupt onset of fever usually accmpanied by myalgia
and
headache. As the disease progresses, wasting becomes evident and bleeding manifestations occur. Culture is positive during the acute stages and seroconversion occurs around day 8-12. Antigen detection ELISA or polymerase chain reaction
amplification of
reverse transcription products have been effective in diagnosis of human cases No individual preventive measures, vaccines, or antiviral chemotherapy are available. Management of the patient should be supportive with minimal trauma and careful
maintenance of hydration. At the community level properly sterilized injection equipment, protection from body fluids during preparation of the dead, and routine barrier nursing precautions are probably adequate in most cases. Extensive
quarantine
precautions are mow in place to prevent movement of infected monkeys. Nevertheless, the potential for emergence of Ebola virus as a significant public health problem may exist and concern by the clinician is warranted when suspicious cases with
an
epidemiologic link to Africa or nonhuman primates occur. If Ebola virus are suspected as the cause of disease in humans or in monkeys, consultation and laboratory diagnosis are available from the maximum containment laboratories that operate in
several
countries. If human cases are diagnosed, they should be treated in isolation wards, with barrier nursing and careful attention to prevent nosocomial or respiratory spread.
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