While the number of shigellosis cases in the state of Florida as a whole has dropped during the first six months of 2015 compared to the same period last year, in Hillsborough County, health officials are reporting a nearly 500% increase in cases from January through June 2015.
Year to date, there have been 168 cases of shigellosis in Hillsborough County, compared with 27 in the same time period of 2014, with the primary strain seen being Shigella sonnei.
According to the Hillsborough County Health Department, from 2007-2014, 75% of all shigellosis cases in Hillsborough County occurred among individuals aged 19 and under. This trend is also echoed in the cases reported so far in 2015, officials note.
Shigellosis cases diarrhea, vomiting, fever, abdominal cramping and tenesmus, and the stool may contain blood or mucous. Incubation period ranges from 1 to 7 days, but is typically between 1 and 3 days. The illness generally lasts 4-7 days, and is self-limited.
Because shigellosis has a low infective dose, it is easily passed person to person and household attack rates can be as high as 40%.
The majority of cases are due to direct or indirect fecal-oral transmission from a symptomatic person or an asymptomatic carrier. Other shigellosis cases may be the result of eating contaminated food, or drinking or swimming in contaminated water. Child care settings are at high risk for outbreaks of shigellosis due to toddlers who are not fully toilet trained and have imperfect hand hygiene.