How long is MRSA contagious for?

Always. Mrsa is a bacteria and can be spread through skin contact, so it is aways contagious.
MRSA. This strain of staphylococcus aureus may or may not produce infection. We are all colonized with staph, usually in our GI tract, but possibly on nasopharynx and skin. Once colonized, by direct contact with others who have this, you then have the potential to become infected, but this usually occurs only after experiencing some defect in the integument (skin and mucous membranes).
Indefinitely. Unfortunately, MRSA can survive indefinitely on hosts. It can survive on non-host surfaces (ie: door knobs, light switches, commodes, tubs, phones, tables, etc.) for days, weeks, or months depending on environmental circumstances.

Related Questions

How long is pulmonary MRSA contagious once antibiotics started?

MRSA. Even if you have been treated you are probably still carrying this on your skin and mucous membranes. Depends on your definition of "contagious". This organism is generally transferred person to person by direct hand contact, and then the other person may only become a carrier. Infection requires a break in the skin or soft tissues or introduction into an immune suppressed person.

How long I am contagious with mrsa?

MRSA. As long as you are a carrier. Depends on your definition of "contagious". This organism is generally transferred person to person by direct hand contact, and then the other person may only become a carrier. Infection requires a break in the skin or soft tissues or introduction into an immune suppressed person.

How long is an MRSA skin infection contagious once antibiotics have been started?

Usually 2-3 days. Particularly if using topical agent as well as oral. May be longer if immune system not normal, or if ongoing drainage (/pus) from wound/abscess.