Acariasis
Acariasis refers to both an infestation of mites and the diseases caused by these tiny arthropods. Mites are diverse and can affect various parts of the body, including the skin, gastrointestinal tract, lungs, and urinary tract. The most common form, cutaneous acariasis, occurs when mites like Sarcoptes scabiei burrow into the skin, leading to allergic dermatitis and severe itching. Mites can also act as vectors for other diseases, with some species transmitting infections such as scrub typhus. Environmental factors such as humidity, overcrowding, and poor hygiene increase the risk of acariasis, as do genetic predispositions in certain individuals.
Symptoms vary based on the affected area, with respiratory, gastrointestinal, and urinary manifestations possible. Diagnosis typically involves microscopic analysis of skin scrapings, stool samples, or urine to identify the presence of mites. Treatment options include topical, oral, and systemic therapies tailored to the specific type of acariasis. Prevention focuses on improving hygiene, reducing overcrowding, and raising public awareness to mitigate risk factors and control outbreaks.
Acariasis
- ANATOMY OR SYSTEM AFFECTED: Gastrointestinal system, skin, urinary system
- ALSO KNOWN AS: Acaridiasis, acarinosis, scabies
Definition
Acariasis is both an infestation of mites and a disease caused by mites.
Causes
Mites are a vast and diverse species of tiny parasitic and free-living arthropods that can infect the skin, gastrointestinal tract, lungs, urinary tract, and other areas of the body. Cutaneous infestation is one of the most common forms of acariasis and occurs when mites, such as Sarcoptes scabiei var. hominis (human scabies), burrow into the skin or hair follicles and deposit proteins that produce an allergic cutaneous dermatitis. The remains of dead dust mites and their fecal matter are also a major source of allergens. These allergens mediate a type 1 hypersensitivity reaction in atopic persons. In addition to causing cutaneous dermatitis and producing allergens, mites can cause illness by acting as vectors for parasitic diseases. For example, the larvae of trombiculid mites, the chigger mite (Trombicula), transmits scrub typhus (tsutsugamushi disease) and other rickettsial agents.
Risk Factors
Mites often thrive and multiply in warm, moist areas and feed on dead skin from humans and animals. Some mites are also highly contagious. Thus, environmental factors such as overcrowding and poor hygiene are important risk factors for acariasis. Other risk factors include delayed treatment of primary cases, which can foster the spread of acariasis, and a lack of public awareness. Some persons may also have a genetic predisposition for developing hypersensitive reactions to mites.
Symptoms
The symptoms of acariasis vary depending on the type of infestation. The inflammation and skin lesions of cutaneous acariasis are often accompanied by severe itching. Infestation of the gastrointestinal tract can present with symptoms such as abdominal pain and diarrhea. Pulmonary acariasis can cause respiratory symptoms such as a runny nose, coughing, sneezing, and wheezing. Acariasis of the urinary tract can result in symptoms of urinary frequency, urinary urgency, and hematuria.
Screening and Diagnosis
The diagnosis of acariasis differs depending on the organ affected. Cutaneous acariasis is diagnosed by the presence of mites and mite eggs in microscopic analysis of skin scrapings. Gastrointestinal acariasis is diagnosed by detection of mites in stools. Pulmonary acariasis is diagnosed by isolating and identifying mites using physical or chemical methods of sputum liquefaction. The presence of mites in microscopic analysis of the urine is helpful in the diagnosis of acariasis of the urinary tract. In addition, blood examination for eosinophils and specific antibodies, and radiographic studies of the affected organs, may be useful in diagnosing acariasis.
Treatment and Therapy
A number of effective topical, oral, and systemic therapies, and avoidance and containment strategies, are available for the treatment of acariasis. The specific treatment plan depends on the type of acariasis being treated. For example, treatment of allergic rhinitis and asthma symptoms in people who are allergic to dust mites includes reducing exposure; taking medications such as antihistamines, decongestants, and topical nasal steroids; and getting allergy shots.
Prevention and Outcomes
Acariasis can be prevented by addressing the risk factors. Preventive measures include reducing overcrowding, improving hygiene, promptly and adequately treating the illness to stop further disease spread, and promoting public awareness of the disease.
Bibliography
Diaz, J. H. “Endemic Mite-Transmitted Dermatoses and Infectious Diseases in the South.” Journal of the Louisiana State Medical Society 162 (2010): 140-145, 147-149.
Goddard, Jerome. Physician’s Guide to Arthropods of Medical Importance. 4th ed. Boca Raton, Fla.: CRC Press, 2002.
"Scabies: Epidemiology, Diagnosis, and Treatment." National Library of Medicine, 15 Oct. 2021, pmc.ncbi.nlm.nih.gov/articles/PMC8743988/. Accessed 3 Feb. 2025.
Service, M. W., ed. Encyclopedia of Arthropod-Transmitted Infections. New York: CABI, 2001.
Shakespeare, Martin. Zoonoses. 2d ed. London: Pharmaceutical Press, 2009.