Merry Christmas, watch out for blood-sucking ticks on the tree!

Ticks, the wee arachnids that feed on the blood of other animals, only freeze at temperatures lower than -7 degrees Celsius, the paper reported. If their tree homes were not exposed to chilly temperatures before being sold, they could survive long enough to become a menace at the holiday hearth.

“While setting up and decorating the tree a tick can get on clothing,” insurance expert Rolf Dockhorn told Bild, adding that this can be particularly dangerous because people are not expecting the little invaders and may not notice them right away.

Ticks carry Lyme disease, or borreliosis, a dangerous bacterial disease, as well as encephalitis, a virus that attacks the nervous system.

Those who venture out for winter walks should also be on their guard for ticks, the paper said. In warmer years they are able to survive and hide in shrubbery from where they can easily attach themselves to passersby.