Prevention of dermatophytosis
Ringworm or tinea (dermatophytosis) includes tinea capitis (head), tinea corporis (body), tinea pedis (feet), tinea cruris (groin) and tinea unguium (nails). Show
Notification is not required. Primary school and childrens services centres exclusion for ringworm or tineaExclude until the day after appropriate treatment has commenced. Infectious agent of ringworm or tineaMicrosporum spp. include Microsporum canis as the primary causative agent in Australia of tinea capitis and tinea corporis. Trichophyton spp. for example, T. rubrum and T. mentagrophytes and Epidermophyton floccosum also cause disease. Clinical featuresThe clinical features of tinea infections are those of superficial fungal infection of the skin, nails or hair:
DiagnosisDiagnosis can be made by microscopic examination of material from the affected area or by fungal culture. Incubation period for ringworm or tineaThe incubation period differs:
Public health significance and occurrence of ringworm or tineaTinea capitis mainly affects children. M. canis is usually contracted from infected kittens or puppies. The highly contagious M. audouinii spreads from person to person and does not occur in Australia. Tinea capitis may extend to tinea corporis. It occurs worldwide. Tinea corporis occurs worldwide and is relatively prevalent. Males are infected more than females. Infection can occur from direct or indirect contact with skin and scalp lesions of infected people or animals. Tinea pedis occurs in children and adults. It is spread via shed skin scales, which may remain infectious on carpet or matting for years. Adults are affected more often than children, and males more often than females. Infection is more frequent and severe in hot weather. Tinea cruris is commonly spread from the affected individuals feet, and hence causative agents and occurrence are similar to tinea pedis. Young men are most frequently affected. Tinea unguium occurs commonly, but rates of transmission are low, even to close family associates. It is spread by direct contact with skin or nail lesions of infected people, or indirectly through contact with contaminated floors or showers. Reservoir for ringworm or tineaReservoirs for tinea are:
Mode of transmission of ringworm or tineaDirect transmission occurs through human-to-human contact for example, for T. rubrum and T. mentagrophytes. Animal-to-human contact also occurs for example, for M. canis and T. verrucosum. Tinea can also be transmitted indirectly through contaminated soil for example, for M. gypseum. Period of communicability of ringworm or tineaActive lesions shed infective material continuously. The fungus persists on contaminated materials for as long as skin cells or animal hair harbour viable spores. Susceptibility and resistance to ringworm or tineaYoung children are particularly susceptible to tinea capitis (M. canis). All ages are susceptible to infections, particularly those caused by Trichophyton spp. Susceptibility to tinea corporis is widespread. It is aggravated by friction and excessive perspiration in axillary and inguinal regions, and when environmental temperatures and humidity are high. Susceptibility is variable for tinea pedis, and infection may be inapparent. Repeated attacks are frequent. An injury to the nail predisposes to tinea unguium infection. Reinfection is frequent. Control measures for ringworm or tineaPreventive measuresMeasures differ according to cause:
Control of caseIn general, cases should be advised not to share towels or clothing with others. Specific control depends on the cause:
Consult the current version of Therapeutic guidelines: antibiotic for detailed guidance on therapy. Note: M. canis infection is self-limiting in children before puberty, and griseofulvin may not be necessary. Consult a specialist about treatment. Investigate household contacts, pets and farm animals for evidence of infection. Treat infected contacts (human or animal). Control of environmentSee Preventive measures. Outbreak measures for ringworm or tineaChildren and parents should be educated about modes of spread, prevention and the necessity of maintaining a high standard of personal hygiene. In case of outbreaks, consider examination of all children to identify cases. Disinfect contaminated articles. |