Steve Doyle of the Huntsville Times has been taking a crash course on E. coli O157:H7.  It also appears that many of the Little Rosie’s customers have become extremely ill – several developing HUS.  His story this morning points to the difficulty at times in pinpointing the actual source of a bacterial illness.  The headline says it all.  I have interjected some questions that still need to be answered in bold:

Lettuce most likely source for E. coli?

Lettuce was the likely source of an E. coli bacteria outbreak that has now sickened 18 people, the Huntsville-Madison County Health Department’s assistant director said Tuesday.  Dr. Debra Williams said all signs point to shredded lettuce served by Little Rosie’s Taqueria as the probable culprit.  [Not too fast – everyone at a Mexican Restaurant eats lettuce or it is on the plate]  Fourteen of the 15 people who have tested positive for E. coli O157:H7 poisoning ate at the Whitesburg Drive restaurant June 28-29, she said. The other victim did not eat there.  [This is an interesting and important fact – 1)  did this victim have ANY contact with anyone who ate at the restaurant – possibly a secondary case, 2)  did the victim eat lettuce or meat that was also served at the restaurant – where did the restaurant and the 15th person buy these food items?]

Health officials are awaiting test results on three other Little Rosie’s customers who have symptoms of E. coli exposure.  [It will be interesting to see the PFGE pattern (genetic fingerprint) of the stool cultures.  It is most likely that  all the people at the restaurant have the same pattern.  It will be interesting to see if the 15th person also share that pattern.]

“We think it was a cross-contamination handling issue” by a restaurant employee, Williams said.  [Probable, but not for sure as yet.  We really need a bit more information on the 15th victim].

Fred Grady, chief of the state health department’s epidemiology division, said it’s “a little premature” to call lettuce the source of the outbreak because his agency is still reviewing information collected from victims and the restaurant.  “There are so many things we can’t say yet because we haven’t looked at the data,” Grady said Tuesday. “Statistically, we ought to be able to make some pretty strong assumptions, but (the investigation) is not nearly complete.”  [I would tend to agree with Fred.  A couple of more questions to ask:  1)  has the genetic pattern of the stool isolates been uploaded to PulseNet, 2)  is the genetic pattern a match to any other E. coli outbreaks or illnesses in the Untied States?

After handling hundreds of E. coli cases in the last 14 years – see, I have learned that it is better to do a complete investigation to find the source of the bacteria – whether it is lettuce or meat.  Other news sources: