A comparison of the DNA shows that the salmonella muenchen strain in Sun Orchard's orange juice is identical with the strain found in 14 people who got sick and have been tested, Dr. John Kobayashi said.
He said an additional 25 cases may ultimately be linked to Sun when all testing is finished. All the cases are from King County, where Seattle is located.
Also under review were at least four cases in Oregon and one involving a New York man who got sick after drinking orange juice at a hotel in Oakland, Calif.
None of the cases involved long-term illnesses or deaths, Kobayashi said. He said other states have been notified of the outbreak.
Salmonella is a bacteria that causes infection of the intestines, typically resulting in diarrhea, cramps, headache, fever, vomiting and dehydration. Treatment consists of rest and drinking plenty of fluids, and infections rarely are life-threatening.
Sun Orchard officials at their headquarters in Tempe, Ariz., were unavailable for comment Monday. The company voluntarily recalled its non-pasteurized orange juice Friday and halted further distribution of the product.
Earlier, scientists had found salmonella in unopened containers of the Sun Orchard orange juice, putting them one step away from a definite link.
A statement issued by Sun Orchard on Saturday said the juice was Sun's only product that has been blended with juice from an outside supplier.
There are 15 more King County cases that tests have shown to be salmonella C-2, which is a larger category that includes the salmonella muenchen strain, Kobayashi said. Further testing may tie the cases directly to Sun.
An additional 10 people in King County have diarrhea and are being tested further, he added. Testing takes several days.
Kobayashi said no other source besides Sun Orchard is suspected.
The 14 original cases ranged in age from a toddler who drank a "smoothie" in a restaurant to an 85-year-old man who drank the orange juice in his retirement home, said Mark Alstead, a spokesman for Public Health-Seattle and King County.