The 750 feet of developed beachfront at Rhode Island’s Spring Lake is scattered with volleyball courts, paddle boats, canoes, food concessions and an entertainment arcade.  That beach, located in Burrillville, did not host the crowd of 2,000 that usually attend its Fourth of July festivities. Instead, days earlier, 92 people who entered the water at Spring Lake left sickened by Shigella bacteria. The Shigella outbreak sent 16 people to area hospitals and by Sunday forced state officials to close the lake to swimmers.  Shigella causes gastrointestinal symptoms, but the illnesses are usually not severe. Rhode Island Health Director Michael Fine advises anyone who swam in Spring Lake on the Fourth of July to consider seeking medical attention if they have gastrointestinal symptoms. Over the next week, Fine expects a few more cases to be added to the outbreak count. However, he says, there have been no severe illnesses.  Rhode Island officials expect to reopen Spring Lake to swimming today as water testing is not showing any further Shigella contamination. Shigella is typically spread by contact with human feces. Most of those who became ill were under 18 years of age. A single ill child, possibility wearing a leaky diaper, might have spread the bacteria to all the others. Both food and water was tested for the bacteria before the lake was pinpointed as the source. Rhode Island typically sees 10 to 15 Shigella cases a year, making the Spring Lake outbreak the largest event of its kind to occur in 20 to 30 years.