Ringworm is a skin disease caused by a fungus similar to the one that causes athlete's foot in people. Young guinea pigs are usually more susceptible than adults. Ringworm in guinea pigs is generally characterized by patchy hair loss on the face, nose and ears. The skin in these areas may appear flaky. Areas of hair loss may extend along the top side of the trunk. A veterinarian must confirm the diagnosis and prescribe topical and/or oral medication. The medications to be used depend on the number of ringworm areas present and their distribution on the body. Ringworm can be transmitted from guinea pigs to people. It is, therefore, important to limit or restrict handling of infected guinea pigs (especially by young children) until their disease has been successfully treated. If handling is necessary, the handler should thoroughly wash his hands afterward.
Lice Infestation: Lice and mites are the most common external parasites of guinea pigs. Lice are tiny, wingless, flattened insects that live within the hair coat both the adults and their eggs are found attached to individual hairs. 2 types of biting lice may parasitize guinea pigs. Both abrade the skin surface and feed off of body fluids that exude through the very superficial wounds they create. Light infestations usually go unnoticed. Heavy infestations are usually accompanied with excessive Itching, scratching and some hair loss. Scabs may also be evident on and around the ears. A veterinarian can confirm the diagnosis by direct examination of the hair coat. Direct examination is usually all that is necessary, though use of a microscope is very helpful. The veterinarian will usually prescribe an insecticide shampoo to treat affected guinea pigs. Lice can be transmitted by direct and intimate contact between infested and uninfected guinea pig Therefore, pet guinea pigs are very unlikely to harbor these parasites unless they are recent acquisitions that were previously in contact with louse-infested guinea pigs. Being placed in close contact with new infested guinea pigs could also infest established pet guinea pigs. Guinea pig lice do not parasitism people.
Mite Infestations (Mange): A mite similar to the scabies mite of people causes serious infestations in pet guinea pig. Mites are microscopic, spider-like organisms that live within the outer layers of the skin. They usually cause intense scratching and significant hair loss. Some cases without scratching have been reported. Some guinea pigs are so miserable because of the infestation that their constant scratching produces serious wounds. They may run wildly or in circles, and occasionally even have convulsions. A veterinarian must do a number of scrapings of the skin to confirm the diagnosis. Successful treatment consists of 1-4 injections of a specific drug (ivermectin) 10-44 days apart. Any wood shavings within the enclosure should be replaced by white paper toweling during treatment to help make the patient more comfortable.
Intestinal Parasite Problems: Intestinal parasites are usually not a significant problem in pet guinea pigs. A protozoan (one-celled organism) parasite may cause coccidiosis in guinea pig. Signs of this disease include weakness, diarrhea and severe weight loss. Pinworm infections of guinea pigs usually go unnoticed. Both of these parasitisms can be diagnosed by a veterinarian by stool examinations. Both are treatable using specific drugs prescribed by the veterinarian. Neither parasite problem is transmissible to people.