How possible are teenagers to get really sick with tick-borne encephalitis?

Encephalitis: is a serious infection of the brain that a range of clinical manifestations from confusion, to paranoid ideations, to seizures and ultimately coma. some of are tick born diseases

Just as possible: as adults who contract the disease. Only a small portion of infected individuals become ill and of those only 20 percent go on to the second more severe phase of the disease. Tick born encephalitis is caused by a virus transmitted by the bite of an infected tick. There is now a vaccine.