Crimean-Congo
hemorrhagic fever (CCHF) is a tick-borne disease caused by the
arbovirus Crimean-Congo hemorrhagic fever virus (CCHFV), which is a
member of the Nairovirus genus (family Bunyaviridae).
Crimean-Congo
hemorrhagic fever (CCHF) is a severe zoonotic disease which affects
people coming into contact with livestock or ticks. It may also be
transmitted through person-to-person transmission by exposure to
infected body fluids.
The genus
Hyalomma of ixodid ticks is the most important vector of the CCHF
virus. Vertebrates including birds and small animals provide excellent
amplifier hosts of both the virus and the tick.
It was
originally reported among farm workers in Crimea, USSR (1944), and
recurs annually in a wide belt across Africa, in the eastern Balkan
States, and in the Soviet Central Asian republics bordering the shores
of the Black and Caspian Seas.
The range of the
CCHF virus is now known to extend form central Asia to India,
Pakistan, Afghanistan, Iran, Iraq, the Middle East, Eastern Europe,
and to most of Saharan and sub-Saharan Africa.
After an
incubation period of approximately 3 to 6 days the abrupt onset of
acute febrile illness occurs.
The first
symptoms are similar to severe influenza and include fever, headache,
severe back and abdominal pain.
The hemorrhagic
fever manifestations occur after several days of illnesses and include
petechial rash, ecchymoses, hematemesis, and melaena.
It is
accompanied by
pneumonitis, pulmonary hemorrhages, and edema and hemorrhages in
mucous membrane and the genitourinary and gastrointestinal tracts.
Cases typically present with some form of hepatitis.
The mortality
rate is 10-50% in different outbreaks with deaths typically occurring
during the second week of illness.
Animal
reservoirs are small wild mammals (especially rodents), domesticated
animals (sheep, cattle, goats, and hares), and birds.
Early diagnosis
is possible in special laboratories using antigen detection by
imunofluorescence or ELISA tests or molecular methods as PCR and
antibody detection.
Tick control
measures need to be emphasized and utilized to prevent CCHF. This
includes spraying camp sites, clothing and danger areas with
acaricides or repellent. Strict isolation of patients with CCHF and a
focus on barrier nursing would help to prevent nosocomial spread.
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