Does your child have a skin lesion that looks like an infected bug bite or spider bite? Odds are good that it’s really a bacterial skin infection caused by a bug called Staph (MRSA). What makes this particular strain of Staph so annoying is that it resists being killed off my many types of antibiotics. And, the skin infection can spread to the entire family. If your child has a tender, red area of skin that seems to be getting worse instead of better—check it out with your doc.