Wikipedia:Videowiki/Tick-borne encephalitis

Introduction
Tick-borne encephalitis is a viral infectious disease involving the central nervous system. It may result in meningitis, encephalitis or meningoencephalitis. The number of cases in Europe have increased by almost 400 percent within the last three decades.



Signs and symptoms
After approximately one week from exposure, non-speciﬁc symptoms begin. These may include fever, tiredness, headache, nausea, vomiting and muscles pains, which last for about 5 days.



Cause
The cause is tick-borne encephalitis virus, a type of Flavivirus, which was first isolated in 1937. Three sub-types exist: European or Western, Siberian, and Far-Eastern tick-borne encephalitis virus.



Transmission
TBE is transmitted by the bite of several species of infected woodland ticks, including Ixodes scapularis, I. ricinus and I. persulcatus, or rarely through the non-pasteurized milk of infected cows.



Structure
TBEV is a positive-sense single-stranded RNA virus, contained in a 40 to 60 nanometer spherical, enveloped capsid. The TBEV genome is approximately 11 kilo bases in size, which contains a five-prime cap, a single open reading frame with three prime and five prime UTR, and is without polyadenylation.



Diagnosis
Detection of specific antibodies combined with typical signs, is the principal method for diagnosis. In more complicated situations, such as after vaccination, testing for presence of antibodies in cerebrospinal fluid may be necessary.



Prevention
Vaccines are very effective and available in areas where the disease is common and at travel clinics.



Treatment
There is currently no specific treatment, measures may involve hospitalization and supportive care based on syndrome severity.



Epidemiology
As of 2011, the disease was most common in Central and Eastern Europe, and Northern Asia. About ten to twelve thousand cases are documented a year.



. . ..