Salmonella outbreak started months ago

Yesterday, the Centers for Disease Control confirmed to the Associated Press that, indeed, a salmonella outbreak is racing across the country, puzzling health officials over its source. It sounds like something that just happened, doesn’t it? But, no, it started in September, and most of the people got sick after December 1.

After the Associated Press story from the Centers for Disease Control hit the Internet, the Minnesota Department of Public Health confirmed that 30 people in Minnesota have gotten sick from salmonella and one 70-year-old woman with other underlying health conditions has died.

Health officials across the country are scrambling to talk to people who’ve been affected, hoping to be able to connect the victims to a common source .

But at least in Massachusetts, health officials have been slow on the uptake. One 7-year-old girl was affected just before Thanksgiving, spent 4 days in the hospital, and her mother is upset that health officials still have not contacted the family.

Presumably, the states have known about the outbreak, but until the Associated Press story, there was no public announcement of it. Anywhere. As of this morning, there is still nothing on the Minnesota Department of Public Health Web site about the outbreak, although there is valuable information there .

“It is often difficult to identify sources of foodborne outbreaks. People may not remember the foods they recently ate and may not be aware of all of the ingredients in food. That’s what makes these types of investigations very difficult,” according to CDC spokesman David Daigle.

Says the CDC’s update:

“In outbreaks like this one, identification of the contaminated product requires conducting detailed standardized interviews with persons who were ill and with non-ill members of the public (“controls”) to compare foods they recently ate and other exposures,” the CDC’s update says. “Using statistical methods, the contaminated item is identified as one to which significantly more ill persons than controls were exposed. … The investigation is labor intensive and typically takes weeks. It is not always successful.”

Scientific American says there may be good reason why news of an outbreak that started last fall is just now being made public.

The agency’s disease trackers, who were criticized for taking three months to trace another large salmonella outbreak last spring to Mexican Serrano peppers, haven’t determined the latest outbreak’s origin. They mistakenly blamed tomatoes for last year’s scourge, costing growers $100 million in sales.

Meanwhile, the University of Minnesota Center for Infectious Disease Research and Policy says an initial suggestion that chicken may be a cause is not correct:

An online newspaper report yesterday that said the CDC had activated its emergency network to investigate the outbreak was incorrect, CDC spokeswoman Lola Russell told CIDRAP News today. She also said a report that chicken was suspected as the source of the outbreak was wrong.

“We’re not in emergency status with this,” Russell said. As for the source, she added, “We don’t know what it is yet. It would be very premature to indicate that it’s chicken or anything else.”

The Center’s director, former state epidemiologist Mike Osterholm will be on MPR’s Midday at 11 to discuss the outbreak.