SAN FRANCISCO (KCBS)  — Health officials in California are warning primary care and eye doctors to be on the lookout for ocular syphilis, as clusters of the disease hit San Francisco and other West Coast cities.

Ocular syphilis is a sexually-transmitted disease that can cause blindness. Symptoms included eye pain, seeing floating spots and blurred vision. These symptoms are usually a complication of primary or secondary syphilis infections.

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There have been eight confirmed cases of ocular syphilis in San Francisco since December. One of those patients lost vision in one eye.

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Washington State has reported six cases so far this year. Los Angeles County is now investigating what may be two new cases.

Officials say the disease occurs mostly among gay men. The Los Angeles Times is reporting some of the recent patients are also HIV positive, including six in San Francisco and two in Seattle.

The AIDS Healthcare Foundation is asking people who may be at risk, particularly men who have sex with men, to be aware, get regular check-ups and use protection to help stop the spread of the disease.

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