| Summary: | The disease known as ébola receives
this denomination for the name of
the closer river to the African district,
where the first cases of the outbreak
were presented in the decades of
the seventies of the 20th century
(1). This zoonosis that is affecting Africa and currently spreading itself to other
continents, attracts attention of the sanitary authorities worldwide.
The virus belongs to the family Filoviridae, genus Ebolavirus (EBOV) and they are
divided in the species Bundibugyo ebolavirus, Reston ebolavirus, Sudan ebolavirus,
Tai Forest ebolavirus y Zaire ebolavirus (2).
The origin of the disease is unknown, the first outbreak of EBOV was reported in
Sudán in 1976 and three weeks later in Zaire, today named Democratic Republic
of the Congo [DRC] (3). Then the frequency of cases decreased, being reported
small outbreaks until that in 1994 the virus began tour in oriental direction, with
progressive increase of the cases since Gabón to DRC and Uganda (4-6). At this
moment, a new outbreak exists that could not have been contained. For September
4th of the year in process, 3707 cases had been reported, including 1848 deaths
(7), distributed between Guinea (771 cases and 494 deaths), Liberia (1698 cases
and 871 deaths), Sierra Leona (1216 cases and 476 deaths), Nigeria (21 cases
and 7 deaths) and Senegal (1 case). Added to the previous information, the last
August 26 the Ministry of Health of the DRC notified to the WHO a new outbreak
in its equatorial province (8).
In an attempt for understanding the natural history of the disease, studies in
vertebrates (bats and rodents) and arthropods related to the index case or site
of the outbreak have been carried out, without viral isolation or antibodies anti-
EBOV obtained (9,10). Due to the fact that the monkeys develop a hemorrhagic
symptomatology similar to that of the human beings with later death, they are
not considered to be asymptomatic carriers (11). It has been indicated that a bat
lodges the virus, also apparently the antelopes and the porcupine. An important
emptiness of knowledge exists in the matter.
In 1999, 242 small mammals were studied, detecting the EBOV glycoprotein and
sequences of the gene of the polymerase in animals belong to two genuses of
rodents and a specie of shrew (12), indicated as reservoir of the disease.
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