SAN FRANCISCO (CBS SF)–The state Department of Public Health is warning the public of the dangers of consuming raw milk after six Bay Area residents fell seriously ill, state public health officials announced Tuesday.

All six patients were diagnosed with campylobacteriosis, a bacterial infection that occurs after consuming contaminated raw milk, public health officials said.

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Those with the infection may experience diarrhea, abdominal pain, fever, nausea and vomiting within two to five days after exposure, according to public health officials.

The infection can persist for a week or more, state public health officials said.

Young children, the elderly and people with weak or compromised immune systems may have a severe reaction to the illness, according to public health officials.

While most people with the infection make a full recovery, some are left with long-term arthritis or paralysis, public health officials said.

Animal milk can be contaminated with dangerous bacteria if it has not been pasteurized to kill germs, public health officials said.

In the past decade nationwide, the consumption of raw milk has led to outbreaks including campylobacter, E. coli and salmonella, many involving young children, according to public health officials.

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It is difficult to determine if milk is raw because the beverage does not have a smell or appearance distinct from uncontaminated milk, public health officials said.

Sales of raw milk are legal from some dairies in the state, but state public health officials do not recommend people drink it or serve it to children.

Products with raw milk have a warning label informing consumers of the potential microorganisms inside and the potential health risks if it is consumed.

On Sunday, a statewide recall was issued for Claravale Farm in San Benito County after raw milk and raw cream samples tested positive for campylobacter, but there were no reported illnesses associated with the products, state public health officials said.

Products with code dates of March 28 or earlier should be disposed, public health officials said.

One of the farm’s distributors is Real Food Bay Area, a Palo Alto-based organization that makes deliveries in Santa Clara, San Mateo, San Francisco, Alameda, Contra Costa and Solano counties.

Another distributor of the farm’s products is Santa Cruz Local Foods.

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