Mesleas is extremely infectious, and health officials have identified several potential exposure locations across the county.

If you think you’ve been exposed to measles, do not show up at a clinic or hospital without calling first, Public Health — Seattle & King County said. To avoid possibly spreading measles, limit contact with others and wear a well-fitting mask if you need to go to a health care facility, the department said.

There were three cases of measles in King County last year. The new case was confirmed on Wednesday. The infant is suspected to have been exposed to measles during recent travel a