1, lice are mainly parasitic

The hosts are mainly: terrestrial mammals, a few sea mammals, humans are also often parasitic. Lice not only suck blood harm, and make the host itchy, and can infect many important human and animal diseases

2, the right temperature and humidity, and enough food

Human head lice parasitized in the head of the part of the human head with hair, egg laying in the root of the hair, in order to the ear behind the more. Parasitic lice are only adapted to the temperature and humidity of the normal human body surface and suck human blood to sustain their life activities.

Expanded Information:

Lice Harm

When lice bite the human body, the secretion of saliva into the human skin to make the skin itchy, scratching, scratching can be the skin, and then lead to secondary lice. The skin can be broken, which in turn leads to secondary infections and the formation of abscesses. When lice suck blood, they can also spread many kinds of diseases. Body lice and head lice are considered to be the main vectors of epidemic typhus and lice fever, and body lice can also spread trench fever. When wars or natural disasters occur, lice are more conducive to the spread of disease due to the decline in hygiene levels and the relative concentration of people. In addition, lice-borne diseases are more prevalent in winter and are related to personal hygiene.

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