An outbreak of a serious gastrointestinal illness connected to consumption of raw milk from an Alaska dairy is ongoing, with seven confirmed cases and 11 more that are suspected, state health officials said in a bulletin published Thursday.
The outbreak connected to unpasteurized milk began in May and has continued into July, the report said.
The same rare strain of the Campylobacter pathogen was found in all seven cases confirmed in laboratory tests. And it also was confirmed in manure samples from the unnamed Mat-Su farm.
The lab report, combined with the fact everyone who got sick drank raw milk from the same dairy, "affirms the conclusion that this outbreak is due to consumption of Farm A raw dairy products," the state bulletin said.
But tests didn't find the pathogen in milk from the farm's bulk tanks.
That's not surprising, said state epidemiologist Joe McLaughlin. Campylobacter jejuni "is notoriously difficult to culture from environmental specimens other than raw stool," Thursday's epidemiology bulletin said.
There are some 2,200 strains of the pathogen and the one identified in the recent outbreak is very rare, McLaughlin said.
Multiple households were affected, the epidemiologist said.
Raw milk samples collected in May and June did test positive for a different pathogen, called listeria, which can cause life-threatening meningitis in children and people with compromised immune systems, the state bulletin said.
State health officials urge patients and health care providers who suspect illness from raw milk to do the tests so the state can monitor the outbreak.
Officials haven't determined how the pathogen gets into the milk. Possibly manure at some point comes into contact with the milk. Or maybe a cow with an infected udder sheds it during the milking, the state bulletin said.
After initial news reports in June, McLaughlin said the state got calls from people saying, "I've had the worst diarrhea of my life for several weeks."
The state hasn't named the farm but Gareth Byers has said his Point MacKenzie dairy was the one implicated. He's cooperated with the investigation and notified his customers. But some people may have drank the milk or eaten something containing it at someone else's house and didn't know there was an issue until they became ill, McLaughlin said.
While it's illegal to sell raw milk at retail stores, Alaska fans of the product get around that by buying shares in a cow.
Reach Lisa Demer at email@example.com or 257-4390.