Epidemiology of tick-borne encephalitis in Switzerland, 2005 to 2011

We provide an update on the epidemiology and disease characteristics of tick-borne encephalitis (TBE) in Switzerland. Data were collected through the mandatory notification system of the Federal Office of Public Health. Between 2005 and 2011, a total of 1,055 TBE cases were reported, with a peak of 244 cases in 2006. The average yearly incidence was 2.0/100,000 inhabitants nationwide, with the highest regional value (7.8/100,000) in eastern Switzerland. Incidence by age peaked in 60-69 year-old patients, males predominated in all age groups. Most patients suffered from meningoencephalitis (n=567) or meningitis (n=246), seven of 1,055 patients (0.7%) died. Of 617 patients who were 40 years and older, 442 (72%) suffered from a severe course of illness, compared to 196 (51%) of 384 patients younger than 40 years. Most patients were not immunised against TBE, and in 33 of 1,055 patients (3%), vaccine failure was found possible. Ongoing surveillance of TBE and intensified efforts in promoting TBE vaccination for the population at risk will be needed in light of its considerable morbidity. .