People with long-term travel or work plans in areas where tick-borne encephalitis (TBE) is endemic may need a tick-borne encephalitis vaccine, especially if they engage in activities where contact with ticks is likely. TBE is a viral central nervous system infection that can be serious. The tick that harbors the virus is mostly found on rodents in warm, forested regions in Eastern Europe, the former Soviet Union, and Asia in the spring and summer. Campers, hikers and forestry workers should practice tick bite prevention strategies and get the tick-borne encephalitis vaccine well in advance of travel.
Ticks spread the disease by biting. Walking through grass or bushes allows ticks to attach themselves clothing or skin. It's easy to not notice a tick bite, since it injects an anesthetic when it bites. Once the tick has fed, it usually drops off. Tick-borne encephalitis also can be contracted by consuming dairy products, specifically unpasteurized, from infected animals. Human spread of TBE is extremely rare, mostly through breastfeeding or blood transfusion.
Symptoms of the disease are usually mild in two-thirds of cases and include fever, muscle pain, and malaise after an incubation period of 7-14 days. The disease can progress to meningitis-like symptoms including confusion, paralysis and swelling of the brain. The neurological phase of the disease requires hospitalization. Supportive care is the only remedy at this point, but mortality is low, around 1%-2% with neurological involvement.
Tick-borne encephalitis vaccine is currently not available in the US, although it is in other countries. For casual travel from the US to affected areas, a tick bite prevention plan is probably all that is needed. Travelers from the US to forested areas or farmland who plan to spend a lot of time outdoors or working in those areas can look into getting vaccinated in Canada. The vaccine should be administered six months in advance of travel. In Europe, vaccine programs are already available for those in affected places.
While tick-borne encephalitis vaccine can help, the best way to avoid this disease is prevention. Wearing long sleeves and long pants tucked into boot tops helps keep ticks off skin. An insecticide containing 30%- 50% N,N-Diethyl-meta-toluamide (DEET) can be sprayed on clothing. All skin should be checked for ticks after returning indoors and the insecticide washed off as soon as possible. A tick found on the body can be removed gently with tweezers, taking care not to squeeze it so its stomach contents will not be injected into the wound.
