Dermatophytosis, also known as ringworm, is a

fungal infection Fungal infection, also known as mycosis, is disease caused by fungi. Different types are traditionally divided according to the part of the body affected; superficial, subcutaneous, and systemic. Superficial fungal infections include common ti ...

of the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple areas can be affected at a given time. About 40 types of fungus can cause ringworm. They are typically of the ''

Trichophyton ''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterized ...

'', ''

Microsporum ''Microsporum'' is a genus of fungi that causes tinea capitis, tinea corporis, ringworm, and other dermatophytoses (fungal infections of the skin). ''Microsporum'' forms both macroconidia (large asexual reproductive structures) and microconidia ...

'', or ''

Epidermophyton ''Epidermophyton'' is a genus of fungus causing superficial and cutaneous mycoses, including ''E. floccosum'', and causes tinea corporis (ringworm), tinea cruris (jock itch), tinea pedis (athlete's foot), and tinea unguium Dermatophytosis ...

'' type. Risk factors include using public showers, contact sports such as

wrestling Wrestling is a series of combat sports involving grappling-type techniques such as clinch fighting, throws and takedowns, joint locks, pins and other grappling holds. Wrestling techniques have been incorporated into martial arts, combat ...

, excessive sweating, contact with animals,

obesity Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's we ...

, and

poor immune function Immunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reacti ...

. Ringworm can spread from other animals or between people. Diagnosis is often based on the appearance and symptoms. It may be confirmed by either culturing or looking at a skin scraping under a

microscope A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisibl ...

. Prevention is by keeping the skin dry, not walking barefoot in public, and not sharing personal items. Treatment is typically with

antifungal cream An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as cryp ...

s such as

clotrimazole Clotrimazole, sold under the brand name Lotrimin, among others, is an antifungal medication. It is used to treat vaginal yeast infections, oral thrush, diaper rash, tinea versicolor, and types of ringworm including athlete's foot and jock itch ...

miconazole Miconazole, sold under the brand name Monistat among others, is an antifungal medication used to treat ring worm, pityriasis versicolor, and yeast infections of the skin or vagina. It is used for ring worm of the body, groin (jock itch), and fee ...

. If the scalp is involved, antifungals by mouth such as

fluconazole Fluconazole is an antifungal medication used for a number of fungal infections. This includes candidiasis, blastomycosis, coccidiodomycosis, cryptococcosis, histoplasmosis, dermatophytosis, and pityriasis versicolor. It is also used to prevent ...

may be needed. Globally, up to 20% of the population may be infected by ringworm at any given time. Infections of the groin are more common in males, while infections of the scalp and body occur equally in both sexes. Infections of the scalp are most common in children while infections of the groin are most common in the elderly. Descriptions of ringworm date back to

ancient history Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history cove ...

Signs and symptoms

Infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dise ...

s on the body may give rise to typical enlarging raised red rings of ringworm. Infection on the skin of the feet may cause

athlete's foot Athlete's foot, known medically as ''tinea pedis'', is a common skin infection of the feet caused by a fungus. Signs and symptoms often include itching, scaling, cracking and redness. In rare cases the skin may blister. Athlete's foot fungus m ...

and in the groin,

jock itch Jock may refer to: Common meanings * Jock (stereotype), a North American term for a stereotypical male athlete * Jock, a derogatory term for Scottish people mostly used by the English * Short for jockstrap, an item of male protective undergarmen ...

. Involvement of the nails is termed

onychomycosis Onychomycosis, also known as tinea unguium, is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Toenails or fingernails may be affected ...

, and they may thicken, discolour, and finally crumble and fall off. They are common in most adult people, with up to 20% of the population having one of these infections at any given moment. Animals including dogs and cats can also be affected by ringworm, and the disease can be transmitted between animals and humans, making it a

zoonotic disease A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a bacterium, virus, parasite or prion) that has jumped from a non-human (usually a vertebrate) to a human. ...

. Specific signs can be: * red, scaly, itchy or raised patches * patches may be redder on outside edges or resemble a ring * patches that begin to ooze or develop a blister * bald patches may develop when the scalp is affected * nails may thicken, discolour or begin to crack

Causes

Fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

thrive in moist, warm areas, such as

locker room A locker is a small, usually narrow storage compartment. They are commonly found in dedicated cabinets, very often in large numbers, in various public places such as locker rooms, workplaces, elementary schools, middle and high schools, trans ...

tanning bed Indoor tanning involves using a device that emits ultraviolet radiation to produce a cosmetic tan. Typically found in tanning salons, gyms, spas, hotels, and sporting facilities, and less often in private residences, the most common device is a ho ...

swimming pool A swimming pool, swimming bath, wading pool, paddling pool, or simply pool, is a structure designed to hold water to enable Human swimming, swimming or other leisure activities. Pools can be built into the ground (in-ground pools) or built ...

s, and

skin fold Skin folds or skinfolds are areas of skin that are naturally folded. Many skin folds are distinct, heritable anatomical features, and may be used for identification of animal species, while others are non-specific and may be produced either by ind ...

s; accordingly, those that cause dermatophytosis may be spread by using

exercise machine An exercise machine is any machine used for physical exercise. These range from simple spring-like devices to computerized electromechanical devices to recirculating-stream swimming pools. Most exercise machines incorporate an ergometer. An ergome ...

s that have not been disinfected after use, or by sharing towels, clothing, footwear, or hairbrushes.

Diagnosis

Dermatophyte infections can be readily diagnosed based on the history, physical examination, and potassium hydroxide (KOH) microscopy.

Classification

A number of different species of fungus are involved in dermatophytosis.

Dermatophytes Dermatophyte (from Greek '' derma'' "skin" (GEN ''dermatos'') and ''phyton'' "plant") is a common label for a group of fungus of ''Arthrodermataceae'' that commonly causes skin disease in animals and humans. Traditionally, these anamorphic (as ...

of the genera ''

'' and ''

'' are the most common causative agents. These fungi attack various parts of the body and lead to the conditions listed below. The Latin names are for the conditions (disease patterns), not the agents that cause them. The disease patterns below identify the type of fungus that causes them only in the cases listed: * Dermatophytosis **

Tinea pedis Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple ar ...

(

): fungal infection of the feet **

Tinea unguium Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple a ...

: fungal infection of the

fingernail A nail is a claw-like plate found at the tip of the fingers and toes on most primates. Nails correspond to the claws found in other animals. Fingernails and toenails are made of a tough protective protein called alpha-keratin, which is a polymer. ...

s and

toenail A nail is a claw-like plate found at the tip of the fingers and toes on most primates. Nails correspond to the claws found in other animals. Fingernails and toenails are made of a tough protective protein called alpha-keratin, which is a polymer. ...

s, and the nail bed **

Tinea corporis Tinea corporis is a fungal infection of the body, similar to other forms of tinea. Specifically, it is a type of dermatophytosis (or ringworm) that appears on the arms and legs, especially on glabrous skin; however, it may occur on any superficial ...

: fungal infection of the arms, legs, and trunk **

Tinea cruris Tinea cruris, also known as jock itch, is a common type of contagious, superficial fungal infection of the groin and buttocks region, which occurs predominantly but not exclusively in men and in hot-humid climates. Typically, over the upper inner ...

(

): fungal infection of the groin area **

Tinea manuum Tinea manuum is a fungal infection of the hand, mostly a type of dermatophytosis Dermatophytosis, also known as ringworm, is a fungal infection of the skin. Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in ...

: fungal infection of the

hands A hand is a prehensile, multi-fingered appendage located at the end of the forearm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each " ...

and palm area **

Tinea capitis Tinea capitis (also known as "herpes tonsurans", "ringworm of the hair", "ringworm of the scalp", "scalp ringworm", and "tinea tonsurans") is a cutaneous fungal infection (dermatophytosis) of the scalp. The disease is primarily caused by dermatoph ...

: fungal infection of the scalp and hair **

Tinea faciei Tinea faciei is a fungal infection of the skin of the face. It generally appears as a photosensitive painless red rash with small bumps and a raised edge appearing to grow outwards, usually over eyebrows or one side of the face. It may feel wet or ...

(face fungus): fungal infection of the face **

Tinea barbae Tinea barbae is a fungal infection of the hair. Tinea barbae is due to a dermatophytic infection around the bearded area of men. Generally, the infection occurs as a follicular inflammation, or as a cutaneous granulomatous lesion, i.e. a chronic in ...

: fungal infestation of facial hair * Other superficial mycoses (not classic ringworm, since not caused by dermatophytes) **

Tinea versicolor Tinea versicolor (also pityriasis versicolor) is a condition characterized by a skin eruption on the trunk and proximal extremities. The majority of tinea versicolor is caused by the fungus '' Malassezia globosa'', although ''Malassezia furfur'' i ...

: caused by ''

Malassezia furfur ''Malassezia furfur'' (formerly known as ''Pityrosporum ovale'' in its hyphal form) is a species of yeast (a type of fungus) that is naturally found on the skin surfaces of humans and some other mammals. It is associated with a variety of dermat ...

'' **

Tinea nigra Tinea nigra, also known as superficial phaeohyphomycosis and Tinea nigra palmaris et plantaris, is a superficial fungal infection, a type of phaeohyphomycosis rather than a tinea, that causes usually a single 1–5 cm dark brown-black, non ...

: caused by ''

Hortaea werneckii ''Hortaea werneckii'' is a species of yeast in the family Teratosphaeriaceae. It is a black yeast that is investigated for its remarkable halotolerance. While the addition of salt to the medium is not required for its cultivation, ''H. werneckii' ...

Prevention

Advice often given includes: * Avoid sharing clothing, sports equipment, towels, or sheets. * Wash clothes in hot water with

fungicidal Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. A fungistatic inhibits their growth. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, ...

soap after suspected exposure to ringworm. * Avoid walking barefoot; instead wear appropriate protective shoes in locker rooms and sandals at the beach. * Avoid touching pets with bald spots, as they are often carriers of the fungus.

Vaccination

no approved human vaccine exist against ''Dermatophytosis''. For

horses The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million yea ...

dogs The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

and

cats The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of t ...

there is available an approved inactivated vaccine called ''Insol Dermatophyton'' (

Boehringer Ingelheim C.H. Boehringer Sohn AG & Co. is the parent company of the Boehringer Ingelheim group, which was founded in 1885 by Albert Boehringer in Ingelheim am Rhein, Germany. As of 2018, Boehringer Ingelheim is one of the world's largest pharmaceutical ...

) which provides time-limited protection against several

trichophyton ''Trichophyton'' is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp. Trichophyton fungi are molds characterized ...

and

microsporum ''Microsporum'' is a genus of fungi that causes tinea capitis, tinea corporis, ringworm, and other dermatophytoses (fungal infections of the skin). ''Microsporum'' forms both macroconidia (large asexual reproductive structures) and microconidia ...

fungal strains. With cattle, systemic vaccination has achieved effective control of ringworm. Since 1979 a Russian live vaccine (LFT 130) and later on a Czechoslovakian live vaccine against bovine ringworm has been used. In Scandinavian countries vaccination programmes against ringworm are used as a preventive measure to improve the hide quality. In Russia, fur-bearing animals (silver fox, foxes, polar foxes) and rabbits have also been treated with vaccines.

Treatment

Antifungal treatments include

topical agent A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

s such as

terbinafine Terbinafine, sold under the brand name Lamisil among others, is an antifungal medication used to treat pityriasis versicolor, fungal nail infections, and ringworm including jock itch and athlete's foot. It is either taken by mouth or applied to ...

ketoconazole Ketoconazole, sold under the brand name Nizoral among others, is an antiandrogen and antifungal medication used to treat a number of fungal infections. Applied to the skin it is used for fungal skin infections such as tinea, cutaneous candid ...

, or

tolnaftate Tolnaftate (INN) is a synthetic thiocarbamate used as an anti-fungal agent that may be sold without medical prescription in most jurisdictions. It is supplied as a cream, powder, spray, liquid, and liquid aerosol. Tolnaftate is used to treat f ...

applied twice daily until symptoms resolve — usually within one or two weeks. Topical treatments should then be continued for a further 7 days after resolution of visible symptoms to prevent recurrence. The total duration of treatment is therefore generally two weeks, but may be as long as three. In more severe cases or scalp ringworm,

systemic treatment Systemic administration is a route of administration of medication, nutrition or other substance into the circulatory system so that the entire body is affected. Administration can take place via enteral administration (absorption of the drug throu ...

with oral medications may be given. To prevent spreading the infection, lesions should not be touched, and good hygiene maintained with washing of hands and the body. Misdiagnosis and treatment of ringworm with a

topical steroid Topical steroids are the topical forms of corticosteroids. Topical steroids are the most commonly prescribed topical medications for the treatment of rash, eczema, and dermatitis. Topical steroids have anti-inflammatory properties and are classifie ...

, a standard treatment of the superficially similar

pityriasis rosea Pityriasis rosea is a type of skin rash. Classically, it begins with a single red and slightly scaly area known as a "herald patch". This is then followed, days to weeks later, by an eruption of many smaller scaly spots; pinkish with a red edge i ...

, can result in

tinea incognito Tinea incognita or Tinea incognito is a fungal infection of the skin masked and often exacerbated by application of a topical immunosuppressive agent. The usual agent is a topical corticosteroid. As the skin fungal infection has lost some of the ...

, a condition where ringworm fungus grows without typical features, such as a distinctive raised border.

History

Dermatophytosis has been prevalent since before 1906, at which time ringworm was treated with compounds of

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

or sometimes

sulfur Sulfur (or sulphur in British English) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula ...

iodine Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a vi ...

. Hairy areas of skin were considered too difficult to treat, so the

scalp The scalp is the anatomical area bordered by the human face at the front, and by the neck at the sides and back. Structure The scalp is usually described as having five layers, which can conveniently be remembered as a mnemonic: * S: The ski ...

was treated with

X-rays An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 Picometre, picometers to 10 Nanometre, nanometers, corresponding to frequency, ...

and followed up with

antifungal An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as crypto ...

medication. Another treatment from around the same time was application of

Araroba powder Araroba powder, also known as Bahia powder and Goa powder, is a drug occurring in the form of a yellowish-brown powder, varying considerably in tint, from the Portugal, Portuguese colony of Goa, where it appears to have been introduced about the ye ...

Terminology

The most common term for the infection, "ringworm", is a

misnomer A misnomer is a name that is incorrectly or unsuitably applied. Misnomers often arise because something was named long before its correct nature was known, or because an earlier form of something has been replaced by a later form to which the name ...

, since the condition is caused by

fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

of several different

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

and not by

parasitic worm Parasitic worms, also known as helminths, are large Parasitism#Basic concepts, macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted helminth, soil-transmitted and intestinal parasit ...

Other animals

Ringworm caused by ''

Trichophyton verrucosum ''Trichophyton verrucosum'', commonly known as the cattle ringworm fungus, is a dermatophyte largely responsible for fungal skin disease in cattle, but is also a common cause of ringworm in donkeys, dogs, goat, sheep, and horses. It has a worldw ...

'' is a frequent clinical condition in

cattle Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult mal ...

. Young animals are more frequently affected. The lesions are located on the head, neck, tail, and

perineum The perineum in humans is the space between the anus and scrotum in the male, or between the anus and the vulva in the female. The perineum is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), includi ...

. The typical lesion is a round, whitish crust. Multiple lesions may coalesce in "map-like" appearance. File:Toplin des dieles tiesse vea.jpg, Multiple lesions, head File:Dieles åtoû d' l' ouy åmea.JPG, Around the eyes and on ears File:2 dieles mashale.jpg, On cheeks: crusted lesion (right) File:Viye diele did près.JPG, Old lesions, with regrowing hair File:Diele vea waerot.jpg, On neck and withers File:Dieles cawî åmea.JPG, On perineum Clinical dermatophytosis is also diagnosed in

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...

dog The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s, and

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...

s. Causative agents, besides ''Trichophyton verrucosum, are'' ''T. mentagrophytes'', ''T. equinum'', ''Microsporum gypseum'', ''M. canis'', and ''M. nanum''. Dermatophytosis may also be present in the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

eutriconodont Eutriconodonta is an order of early mammals. Eutriconodonts existed in Asia, Africa, Europe, North and South America during the Jurassic and the Cretaceous periods. The order was named by Kermack ''et al.'' in 1973 as a replacement name for the ...

mammal ''

Spinolestes ''Spinolestes'' is an extinct mammal genus from the Early Cretaceous of Spain. A gobiconodontid eutriconodont, it is notable for the remarkable degree of preservation, offering profound insights to the biology of non-therian mammals.Thomas Martin ...

'', suggesting a

Mesozoic The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...

origin for this disease.

Diagnosis

Ringworm in pets may often be asymptomatic, resulting in a carrier condition which infects other pets. In some cases, the disease only appears when the animal develops an

immunodeficiency Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that a ...

condition. Circular bare patches on the skin suggest the diagnosis, but no lesion is truly specific to the fungus. Similar patches may result from

allergies Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derma ...

sarcoptic mange Mange is a type of skin disease caused by parasitic mites. Because various species of mites also infect plants, birds and reptiles, the term "mange", or colloquially "the mange", suggesting poor condition of the skin and fur due to the infection ...

, and other conditions. Three species of fungi cause 95% of dermatophytosis in pets: these are ''

Microsporum canis ''Microsporum canis'' is a pathogenic, asexual reproduction, asexual fungus in the phylum Ascomycota that infects the upper, dead layers of skin on domesticated cats, and occasionally dogs and humans. The species has a worldwide distribution. Ta ...

'', ''

Microsporum gypseum ''Microsporum gypseum'' is a soil-associated dermatophyte that occasionally is known to colonise and infect the upper dead layers of the skin of mammals. The name refers to an asexual "form-taxon" that has been associated with four related biolo ...

'', and ''

Trichophyton mentagrophytes ''Trichophyton mentagrophytes'' is a species in the fungal genus ''Trichophyton''. It is one of three common fungi which cause ringworm in companion animals. It is also the second-most commonly isolated fungus causing tinea infections in humans, ...

''.

Veterinarian A veterinarian (vet), also known as a veterinary surgeon or veterinary physician, is a medical professional who practices veterinary medicine. They manage a wide range of health conditions and injuries in non-human animals. Along with this, vet ...

s have several tests to identify ringworm infection and identify the fungal species that cause it: Woods test: This is an

ultraviolet light Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...

with a magnifying lens. Only 50% of ''M. canis'' will show up as an apple-green fluorescence on hair shafts, under the UV light. The other fungi do not show. The fluorescent material is not the fungus itself (which does not fluoresce), but rather an excretory product of the fungus which sticks to hairs. Infected skin does not fluoresce. Microscopic test: The veterinarian takes hairs from around the infected area and places them in a staining solution to view under the microscope. Fungal spores may be viewed directly on hair shafts. This technique identifies a fungal infection in about 40%–70% of the infections, but cannot identify the species of dermatophyte. Culture test: This is the most effective, but also the most time-consuming, way to determine if ringworm is on a pet. In this test, the veterinarian collects hairs from the pet, or else collects fungal spores from the pet's hair with a toothbrush, or other instrument, and inoculates fungal media for culture. These cultures can be brushed with transparent tape and then read by the veterinarian using a microscope, or can be sent to a pathological lab. The three common types of fungi which commonly cause pet ringworm can be identified by their characteristic spores. These are different-appearing

macroconidia A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an Asexual reproduction, asexual, non-motility, motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are al ...

in the two common species of ''Microspora'', and typical

microconidia A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamydoconidium (), is an asexual, non-motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to th ...

in ''Trichophyton'' infections. Identifying the species of fungi involved in pet infections can be helpful in controlling the source of infection. ''M. canis'', despite its name, occurs more commonly in domestic cats, and 98% of cat infections are with this organism. It can also infect dogs and humans, however. ''T. mentagrophytes'' has a major reservoir in

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...

s, but can also infect pet

rabbit Rabbits, also known as bunnies or bunny rabbits, are small mammals in the family Leporidae (which also contains the hares) of the order Lagomorpha (which also contains the pikas). ''Oryctolagus cuniculus'' includes the European rabbit speci ...

s, dogs, and horses. ''M. gypseum'' is a soil organism and is often contracted from gardens and other such places. Besides humans, it may infect rodents, dogs, cats, horses, cattle, and swine.

Treatment

Pet animals

Treatment requires both systemic oral treatment with most of the same drugs used in humans—terbinafine, fluconazole, or itraconazole—as well as a topical "dip" therapy. Because of the usually longer hair shafts in pets compared to those of humans, the area of infection and possibly all of the longer hair of the pet must be clipped to decrease the load of fungal spores clinging to the pet's hair shafts. However, close shaving is usually not done because nicking the skin facilitates further skin infection. Twice-weekly bathing of the pet with diluted

lime sulfur In horticulture, lime sulfur (British spelling lime sulphur) is mainly a mixture of calcium polysulfides and thiosulfate (plus other reaction by-products as sulfite and sulfate) formed by reacting calcium hydroxide with elemental sulfur, used in p ...

dip solution is effective in eradicating fungal spores. This must continue for 3 to 8 weeks. Washing of household hard surfaces with 1:10 household

sodium hypochlorite Sodium hypochlorite (commonly known in a dilute solution as bleach) is an Inorganic chemistry, inorganic chemical compound with the chemical formula, formula NaOCl (or NaClO), comprising a sodium cation () and a hypochlorite anion (or ). It may ...

bleach Bleach is the generic name for any chemical product that is used industrially or domestically to remove color (whitening) from a fabric or fiber or to clean or to remove stains in a process called bleaching. It often refers specifically, to ...

solution is effective in killing spores, but it is too irritating to be used directly on hair and skin. Pet hair must be rigorously removed from all household surfaces, and then the

vacuum cleaner A vacuum cleaner, also known simply as a vacuum or a hoover, is a device that causes suction in order to remove dirt from floors, upholstery, draperies, and other surfaces. It is generally electrically driven. The dirt is collected by either a ...

bag, and perhaps even the vacuum cleaner itself, discarded when this has been done repeatedly. Removal of all hair is important, since spores may survive 12 months or even as long as two years on hair clinging to surfaces.

Cattle

bovine Bovines (subfamily Bovinae) comprise a diverse group of 10 genera of medium to large-sized ungulates, including cattle, bison, African buffalo, water buffalos, and the four-horned and spiral-horned antelopes. The evolutionary relationship betwee ...

s, an infestation is difficult to cure, as

is uneconomical. Local treatment with

compounds is time-consuming, as it needs scraping of crusty lesions. Moreover, it must be carefully conducted using

glove A glove is a garment covering the hand. Gloves usually have separate sheaths or openings for each finger and the thumb. If there is an opening but no (or a short) covering sheath for each finger they are called fingerless gloves. Fingerless glov ...

s, lest the worker become infested.

Epidemiology

Worldwide, superficial fungal infections caused by dermatophytes are estimated to infect around 20-25% of the population and it is thought that dermatophytes infect 10-15% of the population during their lifetime.Pires, C. A. A., Cruz, N. F. S. da, Lobato, A. M., Sousa, P. O. de, Carneiro, F. R. O., & Mendes, A. M. D. (2014). Clinical, epidemiological, and therapeutic profile of dermatophytosis. ''Anais Brasileiros de Dermatología'', ''89''(2), 259–264

/ref>Oumar Coulibaly, Coralie L'Ollivier, Renaud Piarroux, Stéphane Ranque, Epidemiology of human dermatophytoses in Africa, ''Medical Mycology'', Volume 56, Issue 2, February 2018, Pages 145–161. The highest Incidence (epidemiology), incidence of superficial mycoses result from dermatophytoses which are most

prevalent In epidemiology, prevalence is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seatbelt use) at a specific time. It is derived by comparing the number o ...

in tropical regions.Rajagopalan, M., Inamadar, A., Mittal, A., Miskeen, A. K., Srinivas, C. R., Sardana, K., Godse, K., Patel, K., Rengasamy, M., Rudramurthy, S., & Dogra, S. (2018). Expert Consensus on The Management of Dermatophytosis in India (ECTODERM India). ''BMC dermatology'', ''18''(1), 6

/ref> Onychomycosis, a common infection caused by dermatophytes, is found with varying prevalence rates in many countries.Hayette, M.-P., & Sacheli, R. (2015). Dermatophytosis, Trends in Epidemiology and Diagnostic Approach. ''Current Fungal Infection Reports'', ''9''(3), 164–179

/ref> ''Tinea pedis'' + onychomycosis, ''Tinea corporis'', ''Tinea capitis'' are the most common dermatophytosis found in humans across the world. ''Tinea capitis'' has a greater prevalence in children. The increasing prevalence of dermatophytes resulting in ''Tinea capitis'' has been causing

epidemic An epidemic (from Ancient Greek, Greek ἐπί ''epi'' "upon or above" and δῆμος ''demos'' "people") is the rapid spread of disease to a large number of patients among a given population within an area in a short period of time. Epidemics ...

s throughout Europe and America. In pets, cats are the most affected by dermatophytosis.Gordon, E., Idle, A., & DeTar, L. (2020). Descriptive epidemiology of companion animal dermatophytosis in a Canadian Pacific Northwest animal shelter system. ''The Canadian veterinary journal = La revue veterinaire canadienne'', ''61''(7), 763–770. Pets are susceptible to dermatophytoses caused by ''Microsporum canis'', ''Microsporum gypseum'', and ''Trichophyton''. For dermatophytosis in animals, risk factors depend on age, species, breed, underlying conditions, stress, grooming, and injuries. Numerous studies have found ''Tinea capitis'' to be the most prevalent dermatophyte to infect children across the continent of Africa. Dermatophytosis has been found to be most prevalent in children ages 4 to 11, infecting more males than females. Low

socioeconomic status Socioeconomic status (SES) is an economic and sociological combined total measure of a person's work experience and of an individual's or family's economic access to resources and social position in relation to others. When analyzing a family's ...

was found to be a risk factor for ''Tinea capitis''. Throughout Africa, dermatophytoses are common in hot- humid climates and with areas of overpopulation.

Chronicity A chronic condition is a health condition or disease that is persistent or otherwise long-lasting in its effects or a disease that comes with time. The term ''chronic'' is often applied when the course of the disease lasts for more than three mo ...

is a common outcome for dermatophytosis in India. The prevalence of dermatophytosis in India is between 36.6 and 78.4% depending on the area, clinical subtype, and dermatophyte isolate. Individuals ages 21–40 years are most commonly affected. A 2002 study looking at 445 samples of dermatophytes in patients in Goiânia, Brazil found the most prevalent type to be ''

Trichophyton rubrum ''Trichophyton rubrum'' is a dermatophytic fungus in the phylum Ascomycota. It is an exclusively clonal, anthropophilic saprotroph that colonizes the upper layers of dead skin, and is the most common cause of athlete's foot, fungal infectio ...

'' (49.4%), followed by ''Trichophyton mentagrophytes'' (30.8%), and ''Microsporum canis'' (12.6%). A 2013 study looking at 5,175 samples of ''Tinea'' in patients in Tehran, Iran found the most prevalent type to be ''Tinea pedis'' (43.4%), followed by ''Tinea unguium''. (21.3%), and ''Tinea cruris'' (20.7%).Rezaei-Matehkolaei, A., Makimura, K., de Hoog, S., Shidfar, M. R., Zaini, F., Eshraghian, M., Naghan, P. A., & Mirhendi, H. (2013). Molecular epidemiology of dermatophytosis in Tehran, Iran, a clinical and microbial survey. ''Medical Mycology (Oxford)'', ''51''(2), 203–207

/ref>

References

External links

Tinea photo library at Dermnet
{{Authority control Animal fungal diseases Mycosis-related cutaneous conditions Wikipedia medicine articles ready to translate Cat diseases Wikipedia emergency medicine articles ready to translate

Signs and symptoms

Causes

Diagnosis

Classification

Prevention

Vaccination

Treatment

History

Terminology

Other animals

Diagnosis

Treatment

Pet animals

Cattle

Epidemiology

See also

References

Further reading

External links