The Finnish National Institute for Health and Welfare (THL) has announced that the number of cases of tick-borne encephalitis (TBE) caused by the tick-borne virus has increased in recent years.
According to the Finnish news portal Iltalehti, the increase in the tick population is a consequence of global warming and climate change. They claim that due to the unusually mild winter, ticks have remained active throughout the year.
Sami Salminen, chief physician at Pihlajalinna Punkkibus and Health Services in Western Finland, said:
“Therefore, the number of ticks is expected to continue to increase in the spring and summer, which also increases the risk of tick-borne diseases.”
36% higher risk of developing Lyme disease
According to a review of more than 200 studies by the SOS Lyme Foundation, people living in rural areas have a 36% higher risk of developing Lyme disease as a result of tick bites.
Factors that increase the risk include owning pets, engaging in outdoor activities, working in agriculture, fishing or animal husbandry, and living in northern Spain.
Similarly, activities in areas heavily infested with ticks, such as hiking, camping or fishing, can also contribute to infection. These activities typically take place in natural environments where ticks are abundant, especially in spring when their population is growing rapidly.
“This risk is even higher for those who work in forestry, agriculture or animal husbandry, as their work regularly exposes them to tick habitats. These occupations often involve spending long periods of time in wooded or grassy areas where ticks of the genus Ixodes ricinus are prevalent,” explained Dr. Mariano Bueno, president of the SOS Lyme Foundation and director of the Biosalud Day Hospital.
It is important to note that households with pets are 1.83 times more likely to find ticks in their living environment and 1.49 times more likely to find ticks attached to family members than households without pets.
Cat ownership increases the likelihood of developing Lyme disease by 11.1%, as cats typically roam more freely than dogs, resulting in less owner control, explained Dr. Bueno.
“The reason cats pose a greater risk to humans in terms of Lyme disease than dogs is that when allowed to roam freely, they travel further afield, hunt small rodents, and owners are less likely to use tick prevention measures, such as collars or thorough checks,” he added.
According to a study published in the scientific journal Ticks and Tick-borne Diseases, northern Spain – where most hospitalisations for Lyme disease in the country occur – is particularly affected. This is due to the temperate and humid climate, which is conducive to the spread of ticks, especially in the Cantabrian Mountains region, where it allows Ixodes ricinus nymphs to remain active throughout the year.
Editor’s note:
It is not only spring and summer that pose an increased risk of ticks and the Lyme disease they spread – milder winters due to climate change are also increasing the danger. According to research, most tick species become active at daily average temperatures of around 5–7 °C, at which point they begin to “hunt” for hosts, meaning that they can be encountered outdoors even in late autumn or on milder winter days.
The optimal activity range for ticks is generally between 10–26 °C and high humidity, which is most common in the spring and summer, but it is not uncommon for some to be active even when the daily average temperature rises to around 7 °C for several consecutive days.
This means that even winter does not offer complete safety if the temperature rises temporarily, as ticks do not hibernate in the true sense of the word, but only enter a low-energy resting state – and a mild day may be enough for them to become active.
What can we do to reduce the risk of encountering ticks and contracting diseases?
- Wear appropriate clothing: long-sleeved tops, long trousers, closed shoes and light-coloured clothing help with early detection of ticks.
- Use insect repellents: DEET-containing or other effective tick repellents on clothing and skin.
- Keep your garden tidy: mow the lawn regularly and remove leaves and dense undergrowth to reduce the habitat for ticks.
- Body checks: After any outdoor activity, thoroughly check your body, especially areas that are difficult to see (e.g., behind the knees, armpits, head).
- Protecting our pets: use tick collars, spot-on treatments or tablets, and check their fur frequently.
- Proper tick removal: if you find a tick in your skin, remove it with fine tweezers, pulling it straight out, then disinfect the area.
All these steps are important not only in the spring and summer seasons, but throughout the year, especially during periods when the temperature rises above 5–7 °C for a prolonged period, even in winter.
(C) Lyme Borreliosis Foundation
