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Crimean-Congo hemorrhagic fever:
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Viral weapon acting against humans |
Synopsis, Diagnosis, Symptoms,
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Safety Precautions for Crimean-Congo Hemorrhagic Fever Casualties |
Contact Precautions defined by the 1996 CDC guidelines should be adopted for handling patients.Tick control should be practiced.Biosafety level 4 practices should be adopted for handling of samples. |
| Causative organism: (Systematic name in 1997) | Crimean-Congo hemorrhagic fever virus |
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| Alternative names: | Congo-Crimean hemorrhagic virus |
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| ICTV Acronym | C-CHFV |
| Virus classification: | A Nairovirus, an enveloped spherical virus with two subgenomic
single-stranded RNAs belonging to the Bunyaviruses. Click here for a detailed description of Bunyaviruses |
| Vector involvement | CCHF is carried by several genera of hard-bodied or ixodid ticks including Hyalomma, Dermacentor, Amblyomma and Rhipicephalus. |
Differential DiagnosisOther disease or conditions that need to be eliminated | |
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| Other infectious diseases | Other problems |
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After an incubation period of 2-7 days there is a sudden onset of flu-like symptoms including a severe headache, chills, fever, headache, muscular, lumbar and abdominal pain, nausea and vomiting. After 3-5 days, hemorrhage begins and is seen as a red or purple discoloration of the skin and the development of nosebleeds. In about half of all cases the liver is enlarged (hepatomegaly). Blood is found in saliva, urine, black skin patches and vomit. This will lead to shock, vascular collapse and death about 10 days after the onset of symptoms. If the patient survives and the fever begins to subside, then a long slow recovery is possible.
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| Two images of Crimean-Congo Hemorrhagic Fever patients taken in 1969 showing the characteristic dark patches on the skin. | |
| Source: Centers for Disease Control, Dr. B. E. Henderson, Public Health Image Library #2136 | Source: Centers for Disease Control, Dr. B. E. Henderson, Public Health Image Library #2137 |
Medical and Physical Countermeasures.
Vaccination (Immunoprophylaxis)
A vaccine is not available.
Specific Therapy
Ribavirin is effective and was made available for post-exposure prophylaxis to soldiers in Operation Desert Shield/Storm and in Korea.
Supportive care
Minimize intrusive care to protect a weakened vascular bed. Attempt replacement therapy only in the case of severe hemorrhage. Fluid infusion to deal with dehydration is often counterproductive.
Decontamination
The virus is killed by common disinfectants, solvents, and dry heat (56°C, 30 min.). The vectors (ticks of the genus Hyalomma) also need to be controlled with acaricides and possible animal reservoirs will need to be monitored.
Agent Properties and Potential Uses
The virus is rather fragile and does not survive well outside the host. It is rapidly killed by ultraviolet light. It is very stable in the tick vector and infected ticks remain infected throughout their lives. The disease is found throughout the range of its tick hosts, a band across the Old World stretching from Central Asia and the Ukraine to the Congo and Central Africa. Outbreaks in the Old World may be difficult to identify as attacks unless the attacker is careless.
Mortality is high and it can be used to kill large numbers. However, it can be treated with the antiviral ribavirin.
Terrorist Acquisition and Attempted Use.
| Disease | ICD-9-CM | ICD-10 |
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| Crimean-Congo hemorrhagic fever | 065.0 | A98.0 |
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