(CNN) -- Raw milk from Utah has sickened 45 people, according to the Utah Department of Agriculture and Food.
The cases of campylobacteriosis have been linked to raw milk or cream purchased at Ropelato Dairy in Weber County, the department said in a statement Tuesday. Most of the infections occurred in people from Utah counties, though two were out-of-state residents from California and Idaho.
Inspectors suspended the dairy's license to sell raw milk on August 4, after samples taken at the farm tested positive for campylobacter bacteria.
"What we've discovered is that an employee had not been thoroughly cleaning the udders of the cows," Larry Lewis with the Utah Department of Agriculture and Food told CNN affiliate KSL. "That is introducing contamination, manure and feces that are in that area into the milk, which is a major problem."
Campylobacteriosis is a common bacterial infection that causes diarrhea, abdominal pain and fever, according to the Centers for Disease Control and Prevention. Experts estimate it affects over 1.3 million Americans every year, with more cases happening during the summer months.
The illness typically lasts around a week, though some people with the bacteria don't experience any symptoms at all. Most patients recover without treatment. People with weakened immune systems, such as infants or the elderly, are most at risk for a serious infection.
"In some severe cases, illness can lead to complications, including paralysis and death," Utah epidemiologist Kenneth Davis said. "If you have recently consumed raw milk and are experiencing any of these symptoms, contact your health care provider."
Campylobacteriosis is generally associated with consuming raw or undercooked poultry or dairy products, according to the CDC.
"Unpasteurized milk can become contaminated if the cow has an infection with Campylobacter in her udder or if the milk is contaminated with manure," the health agency's site states.
Since 2009, there have been 14 documented outbreaks of campylobacteriosis associated with raw milk in Utah, according to the Utah Department of Agriculture and Food, with more than 200 people becoming ill.
Raw milk is milk that has not been pasteurized, or heated briefly, to kill harmful bacteria like salmonella, E. coli and campylobacter. Heat can affect a few of the vitamins -- thiamine, vitamin B12 and vitamin C -- that are found in milk, according to the CDC, but it "does not significantly change the nutritional value." The U.S Food and Drug Administration warns consumers against drinking raw milk or eating dairy products made with raw milk.
"Many people believe that foods with no or minimal processing are better for their health," the CDC says. "Many people also believe that small, local farms are better sources of healthy food. However, some types of processing are needed to protect health."