Tick-borne encephalitis

Tick-borne encephalitis (TBE) is a viral infectious disease involving the central nervous system, transmitted by the bite of several species of infected ticks. The disease most often manifests as meningitis, encephalitis or meningoencephalitis. Myelitis and spinal paralysis also occur. In about one third of cases sequelae, predominantly cognitive dysfunction, persist for a year or more. The number of reported cases has been increasing in most countries. TBE is posing a concerning health challenge to Europe, as the number of reported human cases of TBE in all endemic regions of Europe has increased by almost 400% within the last three decades. Historically, TBE virus has been thought to be absent in the UK, but in 2020 Public Health England declared the first two TBE cases contracted within the country. The tick-borne encephalitis virus is known to infect a range of hosts including ruminants, birds, rodents, carnivores, horses, and humans. The disease can also be spread from animals to humans, with ruminants and dogs providing the principal source of infection for humans.