We described the outbreak. We defined a case as a previously healthy resident or visitor in Havana Informal Settlement with acute onset of any two of the following symptoms; vomiting, nausea, headache unconsciousness, body weakness, diarrhea and unsteady gait.
We collected demographic data and food intake history on a standardized line list through face-to-face interviews of parents of ill children. We interviewed the meat seller, the veterinarian who dumped the horse carcass and   dump site workers. Moreover, we searched for additional cases in the affected community and the local clinic.  
