Mode of transmission between humans

Reports of itch mite occurrences

Fig. 75. Previously, doctors reported cases of scabies to the National Health Service in Denmark. From these reports, we know that there are more cases in October-November. In Denmark there are about six thousand cases of scabies every year.

Each year, about 6000 Danes are infected with scabies, and the infection spreads from one person to another. The spreading stage is thought to be the fertilized female mite. The transmission requires close contact for a long time in hot and humid conditions. Sharing a bed with another person is the main cause of transmission. On the skin, a female mite moves at a rate of 2 1/2 cm per minute. When away from the skin, it is badly off. Its movements are slower.

At room temperature, it can only just wiggle the legs and at 16 °C it is immobilized. If you put on underwear or gloves, which an infected person has just removed, you can be infected. If a few hours pass, the risk of infection is small. People are not infected from a distance or by casual contact. A handshake, reading the same newspaper or using the same towel is not enough. In typical, dry living room air, it is only a matter of few days before any mites are dead. Long before then, they have probably lost the ability to infect.