Two Timaru pupils have been discharged from hospital after falling seriously ill with an E. coli infection after drinking raw milk on a school trip to a farm.
South Canterbury medical officer of health Dr Daniel Williams confirmed the South Canterbury District Health Board has been notified of two cases of E. coli involving Waimataitai School pupils who went on a variety of school visits, including to farms, last week.
Two other pupils also fell sick following the farm visit.
"All the children that have been sick have drunk raw milk, but it has not been confirmed what caused the illnesses yet," Williams said.
Waimataitai principal Jane Culhane said pupils from five classes visited seven or eight farms last week as part of their Our Place and Space unit.
She said the cause had not yet been established for the two cases, but the school had alerted parents to the symptoms and what to look out for.
"We always act responsibly, and tell parents anything we feel they need to know," she said.
Williams said it was a timely reminder that when townspeople visited farm environments they needed to be vigilant about washing hands after visiting, and avoid drinking raw milk.
The symptoms of E. coli infection include bloody diarrhoea, urinary tract or other infections, stomach cramps, nausea and vomiting.
The pupils did not visit the Timaru farm of Stuart and Andrea Weir, which has been at the centre of an ongoing campylobacter investigation.
Their farm, which sells raw milk under the brand Village Milk Timaru will resume selling its raw milk today after a "clean run" of testing.
The company shut its doors on March 26 after Community and Public Health confirmed seven cases of people contracting campylobacter were linked to the raw milk purchased from the business on March 7 and 8.
"We have had a clean run of at least five consecutive days. That gives us enough confidence to resume our operations in Timaru," chief executive Mark Houston said.
"It's a product that needs to be well monitored. Rather than hiding under a bushel, we can't be frightened to shut operations down if there's something wrong."
The company has been testing the raw milk daily since March 14.
"We will continue to test the product every day," Houston said. "We thank our customers for their support, and we are sorry for those who were affected."
He said the company did not know the cause of the outbreak. "We don't want to speculate or point fingers. We understand South Canterbury is a bit of a haven for campylobacter."
Health officer Williams said the reported cases could have been "the tip of the iceberg". "Raw milk is a risky product. There could have been dozens affected who decided not to go to a doctor," he said.
Williams said "city people" who purchased raw milk were more likely to be at risk.
"People who have consumed raw milk on farms all their life could have developed immunity to it," he said.
Campylobacter is the most common food-borne illness in New Zealand, with symptoms including diarrhoea, abdominal pain and fever within two to five days of being exposed to the organism.
Ministry for Primary Industries spokesman Jim Flack confirmed investigations were ongoing.
Village Milk's pasteurised milk was unaffected by the campylobacter scare and is still being sold via Fonterra.
- The Timaru Herald
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