As one looks at the numbers, one wonders if this is actually a single outbreak.
Right from the beginning, there was something curious about this distribution of cases. New Mexico early on named names, saying that:
Individuals and restaurants that bought tomatoes from Walmart in Las Cruces or Farmington, Lowe’s in Las Cruces, or Bashas’ in Crownpoint since May 3 should not eat them uncooked.
This was peculiar to us as such chains typically buy through distribution centers, and so we would expect other stores serviced by the DC to have identical product and also have sick people.
At the same time, if, say, Wal-Mart’s DC had bought tomatoes that had this pathogen, it would be a strange coincidence if Lowe’s and Basha’s had also bought from the same farm.
This led us to think, as we said at the time that this might be a case of store managers buying outside their procurement systems.
For a local New Mexico outbreak with four stores in or near Las Cruces implicated, it made perfect sense.
One farmer with tomatoes, selling directly to each of four local stores explains how they would all have the same problem but the other stores serviced by the chain’s distribution center would not.
Now, of course, with the outbreak expanded with sick people in 30 states, our one-farmer theory seems unlikely.
Now we don’t know enough to deduce simply from the map and the numbers. We sometimes think that someone at CDC wants to write a great academic paper, and so they keep information bottled up. After all, if they really wanted to solve this as quickly as possible, they would tap into the collective wisdom of the population by publishing on the Internet all non-confidential information.
What days did people actually report the onset of illness? Are the 27 people in Virginia and Maryland individual local cases or did the Smith family have a reunion in Las Cruces, NM, and they returned home sick?
If the government would make this kind of information available, very smart people all over the world would help it figure out the case — and they would do it for free.
In any case, on a press call there was a reference made by the government to two “bumps” during the course of this outbreak. We look at the distribution of cases and it is easily possible to imagine separate events in the southwest, in the Midwest and, maybe, in the DC metro area.p>
It might even be product of two regions. What if the Southwest and Midwest got Mexican product but Florida sent product to DC metro?
Now, of course, this is classified as one outbreak because it all shares the same genetic fingerprint. But that is an unfortunate term, bringing to mind the distinctiveness of human fingerprints.
That is not how it works. A flock of migratory birds could do its business and leave behind a distinctive “fingerprint,” and then fly somewhere else and do it again.
We don’t have the information to know but, presumably, the reason the traceback hasn’t yet succeeded is that FDA can’t find a common source. The FDA long ago had purchasing records from Wal-Mart, Lowe’s and Basha’s, and New Mexico is very certain they found the retailer where sick people bought tomatoes. Even without “solving” the outbreak for everywhere, that is a lot to go on. And it is the kind of data that should be relatively easily traceable.
If, however this outbreak spreads over several farms, say because they were all drawing on the same irrigation water source, or the same flock of birds visited several farms, then there won’t be a common source.
But why would the FDA by this time not have visited all the farms that the Wal-Mart, Basha’s and Lowe’s traceback led them to?
Curiouser and curiouser.
