Microsporum spp- An Overview


Microsporum spp are a group of fungi that cause various skin infections in humans and animals, collectively known as dermatophytoses or ringworms. These fungi belong to the phylum Ascomycota and the order Onygenales, along with other dermatophytes such as Trichophyton and Epidermophyton.

The habitat of Microsporum spp varies depending on their ecological classification. Some species are geophilic, meaning they live naturally in the soil and can infect humans or animals through contact with contaminated soil. Examples of geophilic species are Microsporum gypseum and Microsporum fulvum. Other species are zoophilic, meaning they primarily infect animals and can be transmitted to humans through contact with infected animals or their hair. Examples of zoophilic species are Microsporum canis and Microsporum nanum. Finally, some species are anthropophilic, meaning they mainly infect humans and can be spread from person to person through direct contact or fomites. Examples of anthropophilic species are Microsporum audouinii and Microsporum ferrugineum.

Microsporum spp are keratinolytic fungi, which means they can degrade keratin, a protein found in the skin, hair and nails of humans and animals. This allows them to colonize the superficial layers of these tissues and cause various types of infections, such as tinea capitis (scalp), tinea corporis (body), tinea pedis (foot) and tinea unguium (nail). These infections are characterized by itching, scaling, redness, inflammation and sometimes hair loss or nail deformity.

Microsporum spp thrive at room temperature of 25-27°C, on keratin surfaces where temperatures are low. They are sensitive to high temperatures and cannot grow above 37°C, which limits their invasion to the nonviable skin tissues. They also require moisture and oxygen for their growth and survival.

Microsporum spp can be isolated from various sources, such as soil samples, animal hair, human skin scrapings, nail clippings or hair plucks. They can be identified by their morphological characteristics, such as the shape, size and wall features of their macroconidia (large asexual spores) and microconidia (small asexual spores), as well as their cultural characteristics, such as the color, texture and pigmentation of their colonies on different media . Some species can also be detected by their fluorescence under Wood`s lamp (ultraviolet light), such as Microsporum canis and Microsporum audouinii.

Microsporum spp are important pathogens that cause significant morbidity and economic losses in humans and animals worldwide. They can be treated with topical or oral antifungal agents, depending on the type and severity of the infection. Prevention and control measures include maintaining good hygiene, avoiding contact with infected individuals or animals, wearing protective clothing and footwear, disinfecting contaminated objects and treating infected animals .