By Jayson Jacoby
Officials from Oregon's Drinking Water Services are weighing two primary factors in deciding when to end the recommendation that Baker City residents boil their tap water to protect against cryptosporidium infection.
One factor is the results of water samples taken on Sunday, said Kari Salis, a technical service manager with the Drinking Water Services office in Portland.
Officials expect to receive those results later today.
The second factor is whether new cases of infection are being reported.
Reporting of new cases is vital because it is a possible indicator of crypto persisting in the city's water, Salis said.
Alternatively, if water samples are negative for crypto, yet people continue to be infected, that would suggest the parasite is being spread by other means, which can be a major problem with crypto, Salis said.
In any case, she urges residents who have the symptoms typically associated with crypto infection - watery diarrhea that lasts for more than a day or two, painful stomach cramps, weight loss, nausea and possibly a low-grade fever - to at least report their symptoms to a doctor.
State officials have asked doctors to pass on such reports, and to recommend patients submit stool samples for lab testing, Salis said.
"Although the initial onset of this outbreak was likely due to the water, secondary infection is also a common problem," she said.
Salis said the state issues boil orders for drinking water somewhere in Oregon "a couple of times a month" on average.
Most of those last no more than a couple of days, she said.
Baker City's boil order was issued the morning of July 31.
Salis said the city's routine tests of both untreated and treated water during July showed levels of coliform bacteria well below the threshold for concern.
Those tests - the city collects 10 samples per month - would not detect crypto, but are instead an indicator of fecal contamination, Salis said.
Crypto is spread in feces, both animal and human.