|Methicillin-Resistant Staphylococcus Aureus or MRSA (usually pronounced "mur-sah")...
is a type of bacteria. Staphylococcus aureus is a common bacterium on skin, and it is not usually a problem. However, when the Staphylococcus aureus bacteria are not susceptible to the antibiotic methicillin (ie, methicillin does not kill the bacteria or stop its growth), it is considered to be MRSA. Bacteria resistant to methicillin are often resistant to other antibiotics as well.
For many years, MRSA was thought to occur only in humans, until a report of a MRSA infection in a dairy cow was reported in 1972. Now it has become an increasingly urgent problem in veterinary medicine, with MRSA infections reported in horses, dogs, cats, pet birds, cattle and pigs.
Not all humans or animals who encounter MRSA develop symptoms. While research is ongoing, it appears only a small percentage become ill, while most eliminate the organism or become colonized without developing any symptoms.
Humans exhibit symptoms ranging from minor skin conditions (pimples, boils and skin infections) to more severe diseases such as postoperative wound infections. MRSA can also cause pneumonia, meningitis (swelling of the tissues surrounding the brain and spinal cord), blood infections, and heart problems.
The most common animal infections occur at surgery sites or skin wound sites, but infections can occur that range from skin infections to pneumonia.
When animals are colonized with MRSA (usually by testing swabs taken of the nostrils), there are no recognized methods for decolonizing them. Based on clinical cases observed, many experts believe companion animals are generally transient carriers of MRSA, meaning they are colonized for about 2-3 weeks, so decolonization is not necessary. Isolating the animal from the human until the animal is no longer colonized is likely to be effective in preventing reinfection of the human.
In cases of skin infections - the most common type of infection found in animals - an option may be either applying antibiotic cream to the skin infection, treat the animal with other antibiotics, or a combination of both. Your veterinarian will determine the appropriate treatment for your animal based on their exam, the animal's history, and the laboratory results.