Denver -- An outbreak of salmonella poisoning in Alamosa in
south-central Colorado spread Thursday, with 111 people likely sick
from the dangerous bacteria, which appears to have contaminated the
city's tap water, officials said.
"This may be the tip of the iceberg," said Julie Geiser,
Alamosa County's director of nursing and public health, during a
press conference in Alamosa. "We think there are a lot more people
out there who have or have had this illness," Geiser said.
Wednesday, the Colorado Department of Public Health and the
Environment issued a bottled water advisory for Alamosa, a town of
about 8,500.
At the time, 79 people were confirmed or suspected of salmonella
poisoning.
Geiser and other officials laid out an emergency plan Thursday,
telling residents where to pick up one free gallon of bottled water
a day.
While there will be an effort to track down the source of the
contamination, Colorado health department spokesman Mark Salley
said, "We may never know."
At Milagro's Coffee House, manager Steve Sumner said everyone
who came in was speculating about how salmonella got into the
city's water.
"There's a lot of gossip out there," Sumner said, saying many
people wondered about sabotage, or about an accident at a
water-treatment plant under construction.
That treatment plant, expected to be in operation later this
year, will remove natural arsenic from the city's water, said Ken
Carlson, an environmental engineering professor at Colorado State
University.
Alamosa's water comes from five deep wells, Carlson said, and is
not disinfected. That is not unusual, he said. More than half of
the drinking water in the United States is untreated groundwater.
In theory, groundwater never comes into contact with
potentially-contaminated surface waters and it does not need
treatment, Carlson said.
"Generally, that's been a good assumption -- there have been
very few outbreaks in these systems," Carlson said.
In the last 20 years the federal Centers for Disease Control and
Prevention has found five case of municipal water contaminated with
salmonella, said Michael Beach, the associate director for healthy
water at the CDC.
One case was similar to Alamosa's with untreated groundwater
somehow becoming contaminated, Beach said.
In two other outbreaks the bacteria got into the
water-distribution system through breaches, Beach said, and in two
other outbreaks a disinfection problem let the bacteria thrive.
Salmonella can cause diarrhea, fever and cramping.