Ticks are a genuine, well-documented seasonal risk in Sweden, active mainly from March to October and especially common in long grass and brush. According to Sweden's official 1177 healthcare guidance, ticks themselves aren't dangerous, but they can carry tick-borne encephalitis (TBE), which can inflame the brain, and Lyme disease (borrelia), for which there's no vaccine. The risk of either rising the longer a tick stays attached, so prompt removal matters.

1177's guidance advises checking dogs, cats and other animals for ticks and removing them as soon as possible, using fine-tipped tweezers gripped close to the skin, pulling straight out rather than twisting. TBE risk is unevenly distributed across Sweden, with higher-risk areas including Uppland, Stockholm County near the coast, Södermanland and Västra Götaland County, though cases occur more widely.

A TBE vaccine exists for people in higher-risk areas, given well in advance of exposure; dogs can also contract TBE, though it's considerably rarer than in people, and a vet is the right first call if a dog shows unusual lethargy, fever or neurological symptoms after a known tick bite. Basic tick-prevention products are sold over the counter at Swedish pharmacies, covered in the Shopping section of this guide.