SAN FRANCISCO (CBS SF) — Two students at San Francisco State University have been diagnosed with chickenpox, prompting officials to send a health warning to students.

The letter states that the second student, who was diagnosed Friday, lived on campus and visited buildings including creative arts, ethnic studies, psychology, the library, student services, the student center and the Towers and Dining Center.

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The first student to be diagnosed does not live in the residence halls, and visited campus on two days during the infectious stage, on Monday Aug. 27 and Wednesday Aug. 29th, according to a letter from Alastair K. Smith, directors of student health services.

The first student visited buildings including creative arts, humanities, science, business, Burk Hall and the bookstore. The student also traveled to and from campus by public transportation on BART and the Muni 28 bus.

Chickenpox is spread airborne particles, respiratory droplets and skin-to-skin contact.

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Exposure to chickenpox in those who are not immune can results in infection in two to three weeks. Symptoms include fever, tiredness, headaches and a rash that turns into itchy, fluid-filled blisters that scab after several days.

Those who have had chicken pox or received two doses of the vaccine should be immune, Smith said. Those who are not immune are at risk of complications from chicken pox if they are pregnant or immune compromised.

If you are not immune and think you have been exposed, contact your health care provider immediately. There may be preventative measures that can be taken within 3-5 days of exposure.

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