Tick-borne encephalitis- record breaking number of cases this summerArticle
19. 08. 2020 General practitioner
A mild winter, rainy weather and a hot summer all- all factors that have contributed to this year’s increased tick activity and the number cases of tick-borne encephalitis.
Tick-borne encephalitis is classed among one of the most dangerous brain diseases in central Europe. The disease is transmitted via ticks (which also are transmitters of other dangerous diseases such as Lyme disease).
Czech Republic is a country with one of the highest risks of transmission of tick-borne encephalitis from a tick to a human. The number of infected ticks in the Czech Republic is anywhere between 2-7%. After the tick attaches, the virus can transmit within a few hours, so removing the tick after a couple of hours might not prevent infection.
This year’s infection rate is still about 25% higher than last year. From January to June of this year, there has been a total of 158 people diagnosed with the disease, and in July it was up to 366 (according to the ISIN register, SZÚ).
The symptoms and stages of the disease
Tick-borne encephalitis affects the meninges and the brain. The course of the disease can be relatively subtle, sometimes even without any symptoms, but it can also be life threatening or deadly in some cases. The first signs of infection present one or two weeks after infection. The incubation period can, however, be up to two weeks. The disease usually runs in two phases.
The symptoms of the first phase relate closely to that of a flu. Fatigue, headache, fever, nausea, joint and muscle pain are all common symptoms. After several days, these symptoms subside, and some patients may recover fully after this phase.
The second phase of the disease is more serious and usually occurs after two weeks and lasts between two and three weeks. Patients suffer from severe headaches, neck stiffness, fever, nausea and vomiting, sleep disturbances, memory problems and light sensitivity. The disease can have lasting consequences on about a quarter of patients- paralysis, balance problems, concentration problems, insomnia or depression.
After the incubation period of one to two weeks, the viral RNA of the disease can be detected in the patient’s blood. However, the disease is commonly mistaken for the common flu, and therefore blood tests are rarely done. In the second phase of the disease, the clinical symptoms are more obvious, and both IgM and IgG antibodies against tick-borne encephalitis are present in the affected patient. These antibodies remain in the body and protect the patient against further occurrences.
The most affective form of prevention against tick-borne encephalitis is vaccination. Unfortunately, the amount of people that are vaccinated in the Czech Republic is still only 29%, although it has been slowly increasing. After vaccination, the body starts creating protective IgG antibodies which remain in the body for a long time. The basic vaccination is administered in three doses. Generally, the vaccine provides protection for about 5 years in patients up to the age of 60, and for about 3 years in patients older than 60. Czech national health insurance companies provide significant coverage of these vaccines.
This article was created in cooperation with MUDr. Petrem Podroužkem, CSc., expert director at EUC Laboratories.