environmental assay data sheet

PCR test for mites

Test code: X0030 - Ultrasensitive detection of mites by real time PCR.  This assay detects most common mite species, including those often found in human habitations.

Mites and ticks are small arthropods belonging to the subclass Acari (also known as Acarina), in class Arachnida. Both mites and ticks pass through four stages of development: egg to larva to nymph to adult. All stages have eight legs except the six-legged larva.

Some mites parasitize animals, including man; others are scavengers. Some mites feed on plants, and many prey on insects and other arthropods. In fact, there are nearly as many different types of mites as there are insects.  Many mites living in human habitations feed on sloughed skin particles and other dust of organic origin.

Rodent and bird mites may bite people when they jump onto people. Three types of rodent mites readily bite humans: the house mouse mite (Liponyssoides saguineus), spiny rat mite (Laelaps echidnina) and tropical rat mite (Ornithonyssus bacoti).

The house mouse mite has a worldwide distribution but is more common in the northeastern United States. The house mouse mite normally sucks the blood of mice, but will also bite rats and people, often causing a rash around the bite. These mites prefer warm places where rodents live. The spiny rat mite feeds on rats at night and hides by day in cracks and crevices around rat nests and resting places. The spiny rat mite is the most common mite occurring on Norway rats and roof rats in the U.S. It is not a known vector of pathogens. The tropical rat mite is not truly tropical, nor does it feed exclusively on rats. This mite can live for up to 10 days off its host and is capable of traveling great distances to find new food sources. The tropical rat mite’s bite is painful and causes skin irritation and itching in humans.

Mites that normally infest birds can also bite people. The northern fowl mite (Ornithonyssus sylviarum) and chicken mite (Dermanyssus gallinae) primarily infest chickens and other poultry but they are also common on many song birds. Mite eggs are laid in nests or on feathers. Hatching occurs in two to three days and adults are seen about five days later if birds are present. The northern fowl mite usually can survive up to two weeks without a bird blood meal. The chicken mite usually hides in cracks and crevices near bird nests during the day and feeds on the birds by night. Cheyletiella mites infest both birds and mammals and they may prey on other mites and insects living on the host’s skin. Bites by Cheyletiella can cause a mange-like condition in pets, and itching in people who handle infested pets. Fortunately, these mites do not stay long on humans.

Diagnosis of mite infection can be achieved by microscopic examination of collected samples. However, molecular detection by polymerase chain reaction (PCR) is increasingly being used to detect the presence of mites in samples.

Utilities:

• Test for mites in HVAC system or on surfaces
• Monitor for mites on pets and other domestic animals and birds
• Selection of appropriate treatment regimens
• Minimize human exposure to mites

Specimen requirements: Dust swab or environmental surface swab or swipe pad.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 3 business days

Methodology: Qualitative real time polymerase chain reaction

Normal range: Nondetected