Patterns of sexually transmitted enteric diseases in a city.

In the past three years cases of shigellosis, amoebiasis, and viral hepatitis A and B have increased fourfold to tenfold in San Francisco. These diseases were most common in people who had adopted "alternative life-styles", especially in young men, In many cases there was a history of frequent orogenital and oral-anal sexual contact between men with no common source. Despite energetic public-health measures and intensive efforts by physicians treating these cases, the increase has not yet been brought under control. Other cities may experience similar difficulties with sexual transmission of enteric diseases.20