Fleas — SOS 4D Paris

The alert most often comes from the dog or cat scratching intensely, biting the base of the tail or losing tufts of fur; on inspection you find at the base of the coat small black grains (droppings) that turn red on contact with damp paper. On humans, bites appear in groups of three or four, especially on ankles and calves, often after returning from holiday or moving into a home that has been empty for a few weeks. On a light parquet, a white sheet or a rug, you spot fleas jumping several centimetres; without intervention, the population explodes within weeks, the pet being only a tiny part of the source (eggs and larvae lodge in fibres and under furniture).

Flea bites cause intense itching, skin lesions and risks of secondary infection, particularly in children. In dogs and cats, they frequently trigger a very debilitating flea-allergy dermatitis (FAD), and transmit tapeworm and various bacteria. The flea's life cycle is so fast — a few weeks, with eggs and pupae that stay resistant for months — that an untreated source systematically re-infests the home and the animals, despite veterinary spot-on treatments alone.

The key is year-round treatment of the pet with a monthly antiparasitic spot-on, vacuuming rugs and sofas twice a week, washing baskets and blankets at 60°C every fortnight, and systematically inspecting the pet after walks in risk areas.