The outbreak traced to the cantaloupe began in early July and has struck consumers in Indiana, Kentucky and Minnesota. Indiana officials said there were about 150 cantaloupe-linked cases nationwide.

"Usually the pattern is to see outbreaks in the summer. But we're seeing about double the number of cases this year," said Dr. Kraig Humbaugh of Kentucky's Department for Public Health.

The illness caused by the food-borne organism usually causes a week-long bout of diarrhea, fever and abdominal pain, but can be fatal for the elderly, young children and people with weakened immune systems. Thousands of Americans contract salmonella illness each year, often from uncooked chicken.

Officials in the three states said they were trying to identify distributors and retail outlets selling the affected cantaloupes, but Indiana and Kentucky officials urged consumers to toss out any of the melons bought recently.

Salmonella strains found in two cantaloupes from southwestern Indiana had the same genetic makeup as those causing a cluster of illnesses in Kentucky, Humbaugh said.

Watermelons from the region were also being investigated as another possible source of a smaller salmonella outbreak, he said.

The current salmonella outbreak comes after cantaloupe tainted with Listeria and traced to a Colorado farm killed 30 people across 11 states last year in the deadliest U.S. food borne outbreak in over a decade.

(Reporting by Andrew Stern; Editing by Cynthia Johnston)

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