In some regions of the country, MRSA is the most common cause of skin and soft tissue infections. This type of staph infection, known as community-acquired, or community-associated, methicillin-resistant Staphylococcus aureus (CA-MRSA), can be carried by healthy adults and children who do not have any symptoms.n some regions of the country, MRSA is the most common cause of skin and soft tissue infections. This type of staph infection, known as community-acquired, or community-associated, methicillin-resistant Staphylococcus aureus (CA-MRSA), can be carried by healthy adults and children who do not have any symptoms.