Despite its name, worms do not cause ringworm infection. Ringworm infection occurs when a hamster's skin becomes infected with a fungus. The most common ringworm-causing fungi are Tricophyton mentagrophytes and Microsporum species.
The ringworm infection is characterized by bald patches, which commonly occur starting from the head. In the face the patches appear around the eyes, nose, and ears. The ringworm infection may also spread to the back. If treated promptly, however, the infection will clear up. Nevertheless, use utmost caution when handling a hamster suspected of being infected, as ringworm is highly contagious to humans and other animals.
Although some hamsters with ringworm infection do not exhibit any external symptoms, the primary sign of the disease is bald patches. Generally, crusty, flaky and/or red lesions form within these bald patches. These lesions may become infected and inflamed and pus-filled. Your hamster may even begin to itch and scratch more than usual.
Most cases of ringworm are caused by the fungus Trichophyton mentagrophytes, though Microsporum fungi can also cause infection in hamsters. Both types of fungi are typically transmitted from infected hamsters or via contaminated objects such as bedding material. Humans can even transmit the disease to their pet hamsters.
Your veterinarian can tell if your hamster is infected with ringworm infection by looking at the red patches on its skin, by shining a special ultraviolet light on its skin, or by conducting various laboratory tests on hair samples taken from the affected area.
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