Shigellosis

1. Shigellosis Bacterial dysentery

2. Microbial Agent • Four species of Shigella: • boydii • dysenteriae (causes deadly epidemics) • flexneri (1/3 of U.S.) • sonnei (about 2/3 of U.S.) • 448,240 cases in U.S. last year for sonnei and flexneri. • dysenteriae occurs mostly in Africa and Central America • Case fatality rates of 5-15%.

3. Signs and Symptoms • Infectious disease causing diarrhea (bloody), fever, and stomach cramps • Usually resolves in 5-7 days. • Children and elderly may have diarrhea so severe they need to be hospitalized. • A severe infection in a child less than 2 may have seizures. • Some show no signs at all, but still pass the Shigella bacteria to others.

4. Diagnosis • Many diseases cause the same symptoms • Determining that Shigella is the cause of the illness depends on laboratory • Tests identify if it is Shigella, and what type • Stools of an infected person are tested Diarrhea with blood and mucus is a typical symptom of Shigella.

5. Treatment and Prevention • Can usually be treated with antibiotics • There is no vaccine to prevent shigellosis • Frequent hand washing can help • Food safety and regular drinking water treatment is best prevention Vegetables could be contaminated by crops harvested from a field with sewage, flies bred in infected feces, and food handlers that are not properly washing their hands