Tick-borne encephalitis

Tick-borne encephalitis (TBE) occurs throughout the northern hemisphere, and mirrors the geographical distribution of the Ixodes species of ticks.

Disease onset is 4 to 28 days after a bite from an infected tick (usually 4 days for foodborne infection).

Diagnosis is made based on immune status; seasonality; geographical, animal, and arthropod exposures; clinical findings; and radiographic abnormalities. TBE is a biphasic illness in most patients.

Treatment consists of supportive care and management of complications. Aciclovir is given empirically until herpes simplex/varicella zoster infection is ruled out.

Most patients recover fully without long-term sequelae, but some patients may experience long-term neurological symptoms or even death.

Vaccines are available for prevention .

Tick-borne encephalitis (TBE) is a flavivirus infection of the central nervous system, characterised by a biphasic meningoencephalitis.[1]Hawker J, Begg N, Reintjes R, et al. Communicable disease control and health protection handbook. 4th ed. Oxford: Wiley Blackwell; 2019 It is caused by the TBE virus, which is usually transmitted by hard ticks of the Ixodes genus.[2]Barlow G, Irving WL, Moss PJ. Infectious diseases and tropical medicine. In: Kumar P, Clark M, eds. Kumar & Clark’s clinical medicine. 9th ed. London: Elsevier; 2016. TBE can also be acquired from consumption of raw (unpasteurised) dairy products from infected animals.[3]Centers for Disease Control and Prevention. CDC Yellow Book 2024: health information for international travel. Section 5: travel-associated infections & diseases - tick-borne encephalitis. May 2023 [internet publication]. https://wwwnc.cdc.gov/travel/yellowbook/2024/infections-diseases/tick-borne-encephalitis ​ This topic focuses on TBE caused by the TBE virus.