Mites are Arachnids, in the same group as ticks and spiders. Adult mites have eight legs and are very small, sometimes microscopic, in size. They are a very diverse group of arthropods and can be found in just about any habitat. Mites are scavengers, predators, or parasites of plants, insects and animals. Some can transmit diseases, cause agricultural losses, affect honey bee colonies, or cause dermatitis and allergies in humans. However, the majority of mites goes unnoticed and have no direct effect on humans.
Some mites may bite humans causing irritation and itchy swellings. Most of them only bite humans when the normal host is unavailable such as the tropical rat mite or the bird mite. Other mites known to cause contact dermatitis include a variety of grain and mold mites. Most mold mites do not bite humans, but can be a nuisance due to the large numbers that can develop within the home. Scabies is a contagious itching disease that is caused by tiny burrowing mites that live under the skin of humans and animals (mange). This disease can spread quickly by physical contact in families, schools and nursing homes if not treated promptly.
The tropical rat mite is the most commonly reported biting mite in Alameda County. The natural host for this mite is rodents, particularly the roof rat. Eliminating rats from the property will solve the mite problem. The bite of this mite does cause severe itching and anxiety, especially in women and young children.
Our District will identify mites, conduct a site evaluation and recommend what action to take to ensure their elimination. Call or submit an online request for service today.
Biting Mites in Homes
Several types of mites are associated with skin dermatitis in humans. The tropical rat mite (Ornithonyssus bacoti), is one of the most commonly encountered species. This mite is a parasite of rats and inhabits the area in and around the rat’s nesting area. The tropical fowl mite (Ornithonyssus bursa), northern fowl mite (Ornithonyssus sylviarum), and chicken mite (Dermanyssus gallinae), associated with domestic or wild birds, can also be found in homes.
Although none of these species are truly parasitic on humans or pets, they will readily bite humans. Some people are unaffected by the bites while others will experience itching and dermatitis (particularly women and children). The bite is normally pimple-sized that itches for up to a week. The bite mark may last as long as three weeks. The bites are often concentrated under areas where clothes constrict the body or areas such as under armpits and breasts. These bites can be extremely itchy and may cause emotional distress. Scratching may also lead to secondary bacterial infections.
The rat and bird mites are very small, approximately the size of a 12-point font period on a piece of paper. They move about quite actively and will enter the living areas of a home when their host, rats or birds, have left or have died. Heavy infestations may cause some mites to search for additional blood meals. A complete generation usually takes about two weeks to develop. Unfed females may live ten days or more after rats have been eliminated. In Alameda County, rodent mites are normally associated with the roof rat (Rattus rattus), but are also occasionally found on the Norway rat, (R. norvegicus) and house mouse (Mus musculus). The tropical rat mite does not vector disease.
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