The bottom line is that the more the CDC and FDA speak, the more obvious it becomes that three months into this outbreak they do not have a rational explanation or even a reasonable theory to explain this Salmonella Saintpaul outbreak.
The latest announcement adds more smoke than light to the outbreak:
An initial epidemiologic investigation in New Mexico and Texas comparing foods eaten by persons who were ill in May to foods eaten by well persons identified consumption of raw tomatoes as strongly linked to illness. A similar but much larger, nationwide study comparing persons who were ill in June to well persons found that ill persons were more likely to have recently consumed raw tomatoes, fresh jalapeno peppers, and fresh cilantro. These items were commonly, though not always, consumed together, so that study could not determine which item(s) caused the illnesses.
Recently, many clusters of illnesses have been identified in several states among persons who ate at restaurants. Most clusters involve fewer than 5 ill persons. Three larger clusters have been intensively investigated. In one, illnesses were linked to consumption of an item containing fresh tomatoes and fresh jalapeno peppers. In the other two, illnesses were linked to an item containing fresh jalapeno peppers and no other of the suspect items. The accumulated data from all investigations indicate that jalapeno peppers caused some illnesses but that they do not explain all illnesses. Raw tomatoes, fresh Serrano peppers, and fresh cilantro also remain under investigation.
Basically the CDC is scrambling for highly unlikely explanations. On today’s conference call, the CDC suggested a search for a farm that had been growing tomatoes and then, perhaps started growing jalapenos midway through the outbreak.
A few key points:
1) This suspicion of jalapenos and Serrano peppers is still just another epidemiological theory — much as CDC had a theory about tomatoes a month ago. With thousands of samples taken, they still haven’t found Salmonella Saintpaul on any jalapenos or anywhere jalapenos were served.
2) CDC hasn’t given the date of the three restaurant clusters, so we don’t know the relevance to public health today.
3) Although illnesses in two of the clusters were linked to items containing jalapeno and no other SUSPECT item, that does not mean they contained only jalapenos. If the outbreak was caused by a non-suspect item, such as tortillas, those items could still be at fault.
4) Note the advisory refers only to those with impaired immune systems — that is always prudent. Note that this is much “softer” than a recall or “recommendation not to consume” — which probably indicates lower confidence in its finding by the CDC.
We think we need an approach that might not show up on the surveys. We want to suggest looking at two other possible vectors for this outbreak:
A) Chicken — via cross-contamination
Chicken is commonly used in Mexican cuisine and is a common carrier of Salmonella. The CDC hasn’t looked at chicken because the surveys don’t show disproportionate consumption by sick people.
What if, though, the chicken is carrying the pathogen but, because it is properly cooked, the chicken itself doesn’t get people ill?
Instead, the raw chicken is improperly handled; it contaminates the produce in the restaurant and that is how people get sick. This would never show up in the CDC surveys as a chicken issue — but it would be.
We think we need to do some swabs at chicken-processing facilities looking for this relatively rare form of Salmonella.
B) Employees — via inadequate hand washing
With over a thousand people sick and a multiplier of over 30 to account for sick people who aren’t counted, we are talking about around 35,000 people estimated to be carrying or have carried this Salmonella Saintpaul strain. Many of these people must work in foodservice.
In the midst of the spinach crisis of 2006, we ran a piece about a Salmonella outbreak at a Wal-Mart store in Indiana. The story included this note from the Indiana Department of Health:
“We believe food handlers who didn’t have any symptoms may have contaminated the deli and bakery products.”
How ever this started — what if it is being spread by those 35,000 sick people, many, perhaps, asymptomatic? There has been zero mention of doing stool samples and health histories on the restaurant workers. We should do both.
When you listen to these calls, one doesn’t get any sense of confidence that the government is on the way to solving this problem. CDC seems to be very caught up in certain standard operating procedures and, perhaps, when an outbreak is this different, it requires thinking outside of one’s training and experience.
It is not obvious that the system set up by CDC and FDA is conducive to this type of creative thinking.