i'm also going to talk about an illness calledtia bella. it is a bacterial infection that causes gast row interitis. the spread is fecal, oral. it is fairly common in the united states rks but much less common here than in developing countries. san francisco normally has about 100 cases a year of what is called shilla loses. there was a large outbreak in the gay community about 15 years ago that went on for over a year and sinss then the levels are fairly stable undill november to december when we saw a increase in cases. so, generally under normal circumstances we have between 5-and 10 shig loses cases a month. they are positive stool cultures a month. it is reported to us which is mandatory. we intervus each case and the main goal of the interview is identify anyone that is in a sentative occupation or setting mainly food handlers. they are not able foowork until they are cleared of dh disease. we look for patterns, outbreak jz generally we don't find anything that is not unique to us. in general shigela outbreaks are not common. however,