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What is tick-borne encephalitis virus?

TBEV is a virus common in ticks in many parts of the world, including parts of Europe. While the risk of contracting the virus is low, it can cause meningitis or encephalitis (swelling of the brain) and, in rare cases, prove fatal.

Why is TBEV a concern?

TBEV causes a range of disease. For most it causes asymptomatic infection, some will experience mild flu-like illness, while a minority will have a severe infection in the central nervous system, such as meningitis or encephalitis. The UKHSA says that in 2020, a total of 3,817 cases were reported in Europe, including 16 associated deaths.

The risk for the general population is very low. Those at higher risk are those who live, work or visit areas where there are infected ticks, which are mainly grassy outdoor areas. All age groups are susceptible to TBEV but older people or those with existing chronic conditions may be at higher risk of mortality and longer-term consequences, and morbidity in children can be significant.

How does TBEV present?

About two thirds of TBEV cases are asymptomatic. In the rest of cases, the incubation is about a week and then the condition generally presents in two phases: first, non-specific symptoms such as fever, fatigue, headache, myalgia and nausea, lasting for about five days. This is followed by an interval of about seven days with no symptoms. Then, the second clinical phase involves presentations such as meningitis, meningoencephalitis, myelitis, paralysis and radiculitis.

What symptoms should nurses look out for?

Nurses should be alert to symptoms of meningitis, such as severe headache, stiff neck and aversion to bright light, high fever or confusion and reduced consciousness, says the UKHSA. They should also be aware that TBEV can cause neurological symptoms including seizures, sudden confusion or change in behaviour, weakness in arms or legs, facial dropping, change in vision or slurred speech.

What are the chances of developing serious complications?

In children, the second phase of illness is usually limited to meningitis, whereas adults aged over 40 years are at increased risk of developing encephalitis, with higher rates of mortality in those aged over 60 years.

What is the treatment?

There is no specific treatment for TBEV. Supportive treatment can significantly reduce morbidity and mortality says the UKHSA.

Is there a vaccination for it and can that be accessed in the UK?

A vaccine is available in the UK but is recommended only for those at high risk due to travel to endemic areas.

What advice should nurses give people on reducing risk?

TBEV can transfer from an infected tick to a person quickly after a bite, unlike Lyme disease when the creature often needs to be attached for some time. This makes advice on avoiding bites particularly crucial. Advise people to cover up in grassy, wild areas, wear long sleeves and trousers, and use a strong insect repellent.