Environmental testing did not aid health officials in identifying the cause of a Salmonella outbreak that occurred at an On the Border restaurant in Vancouver, Wash. beginning in September. As with many foodborne illness outbreaks, the cause will likely remain undetermined, the Columbian reported Wednesday.
As of Wednesday, Clark County Health said the outbreak had a total of 117 cases, including 39 laboratory-confirmed and 78 probable.
Health officials took samples from surfaces around the restaurant, none of which returned positive test results for Salmonella. Those surfaces, however, were washed by restaurant employees prior to inspection, which could have eliminated potential contaminants.
The restaurant was closed between October 9 and 15 as officials investigated the outbreak. Those experiencing symptoms of Salmonella infection ate at the restaurant between September 20 and October 8.