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Tick-borne encephalitis:essential data |
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Viral weapon acting on humans |
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Synopsis, Diagnosis, Symptoms,
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Safety Precautions for Tick-Borne Encephalitis Casualties |
Standard 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) | Tick-borne encephalitis virus |
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| ICTV Acronym | TBEV |
| Alternative disease names: |
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| Virus classification: | A member of the Tick-borne encephalitis virus complex of the Flaviviridae. Click here for a detailed description of Flaviviruses |
| Vector involvement: | The disease is transmitted by the hard-bodied (Ixodid) ticks with Ixodes ricinus and Dermacentor marginatus the most significant vectors. |
The disease first appears as a mild influenza-like fever accompanied by leuko- and thrombocytopenia that clears up within a few days. About 30% of patients go on to develop more severe symptoms with meningitis and meningoencephalitis the most significant developments.
Serological methods may be complicated by cross-reaction of antibodies or antisera with other flaviviruses.
Differential DiagnosisOther disease or conditions that need to be eliminated | |
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| Other infectious diseases | Other problems |
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Symptoms and effects.
After an incubation period of 4-14 days, the patient develops typical flu-like symptoms (headache, fever) that clear up in about a week. After a remission of a few days to a few weeks, about a quarter of patients develop severe symptoms including meningitis or meningoencephalitis. In severe cases, no more than a quarter of cases, a partial paralysis (paresis) may be seen. The European form of the disease is relatively mild and the fatality rate is below 5%.
Although most sufferers recover from the disease, about a third are now believed to have long-lasting neurological problems, including problems with cognition, balance, and coordination.
Medical and Physical Countermeasures.
Vaccination (Immunoprophylaxis)
A vaccine of killed virus is available in Europe and is an investigative new drug in the United States.
Specific Therapy
No specific therapies are available.
Supportive care
The virus is killed by many disinfectants, including 1% sodium hypochlorite, 2% glutaraldehyde, formaldehyde, and 70% ethanol. It is killed by heating at 60°C for 10 minutes.
Agent Properties and Potential Uses
The virus is widespread in Central and Southern Europe where it is normally spread by the bite of ticks of the genus Ixodes. In addition, it can be spread through contaminated milk.
The virus is dependent upon its tick host for survival and tick control using repellents and insecticides such as permethrin should be able to blunt an attack once it is identified.
Terrorist Acquisition and Attempted Use.
| Disease | ICD-9-CM | ICD-10 |
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| Tick-borne encephalitis | 063 | A84 |
| Central European encephalitis | 063.2 | A84.1 |
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