A Clark County teenager who was exposed to measles last month was diagnosed with the disease Wednesday evening, marking the second local case of the highly contagious virus in as many weeks.

Clark County Public Health officials are contacting about 200 people who may have been exposed at the boy’s Vancouver school and medical clinic, said Marni Storey, public health services manager.

The boy attended classes at Vancouver Christian High School on Friday. At the time, the boy was showing only mild symptoms, such as a runny nose and coughing, but he was contagious, said Dr. Alan Melnick, county health officer.

On Tuesday, the boy visited Southwest Medical Group at Fisher’s Landing after developing a rash the night before, Melnick said.

Health officials are contacting about 200 people at the medical clinic and 14 students at the boy’s school who were exposed. Not all of the people who were exposed at the clinic will be susceptible to the illness, Storey said.