Nebraska health authorities say all the people with confirmed diagnoses of salmonella ate at the same cafe in the town of West Point.
The Elkhorn Logan Valley Public Health Department says the number of confirmed cases has been raised to 20 from 15 and adds there are eight probable additional cases.
The department says investigators have determined that all of the people with the illness ate at the Red Door Coffee in West Point.
The department hasn’t determined the specific cause but says the Red Door’s owners and staffers are cooperating with investigators.
Medical experts say salmonella is caused by bacteria and is usually spread by eating contaminated food.