HARRISBURG, Pa. (AP) — The number of people in Pennsylvania and Maryland stricken with illness after consuming raw milk from the same farm has risen to 23, health officials in the two states said Wednesday.

Maryland health officials also said laboratory tests have confirmed the presence of the bacteria, Campylobacter jejuni, that causes the illness in two unopened samples purchased from the Family Cow farm in Chambersburg. Pennsylvania officials said their tests had not yet yielded results.

Nineteen of the 23 people who became ill live in Pennsylvania, officials said. They advised consumers to discard raw milk bought from the farm on or after Jan. 1.

Family Cow says on its website that its raw milk is third-party tested for Campylobacter and other bacteria.

The farm says it sells raw milk at its farm store and at drop-offs, grocery stores and markets around Pittsburgh,
Philadelphia, the Lehigh Valley and south-central Pennsylvania. Raw milk is milk that hasn’t been pasteurized.

The federal Food and Drug Administration warns that raw, or unpasteurized, milk can contain harmful bacteria and Maryland state law prohibits its sale. However, dairy farmers nationwide say demand is growing, spurred by interest in organic foods and concerns about hormones in traditional dairy products.

(Copyright 2012 by The Associated Press. All Rights Reserved.)