What do the US states of Texas, New Mexico, Arizona, Utah, Colorado, Kansas, Idaho, Illinois and Indiana have in common? They are locations of reported illnesses from Salmonella Saintpaul infections, forty in Texas and New Mexico alone, with 17 hospitalizations. Thirty more cases have been reported in the other seven states. The cases are connected by being genetically identical. S. saintpaul is a less common cause of human infection than other non typhoid Salmonella strains and the bugs isolated from these cases are said to be identical. This makes a common source the only reasonable explanation. But a look at the map doesn’t make the source obvious:
Preliminary outbreak investigations in New Mexico implicate uncooked tomatoes, Roma and red round, as a common source. But no infected tomatoes have been located as yet.
There is a larger point, here, than the fact that tomatoes can be a vehicle for a nasty kind of foodborne infection. The map shows that the putative common source is not local. Whatever the source, this very specific bacterium got into the stream of commerce and was widely distributed. The food distribution system is like a huge and ramified tree. Our dinner tables are the leaves on the tree. If you contaminate the roots, the poison spreads to our tables.
A hundred years ago the US reduced epidemic infectious disease — the kind that killed Americans wholesale in its teeming urban slums — not with vaccines or antibiotics. It did it with environmental sanitation, primarily the provision of clean water and clean food. Now our water distribution systems are decaying and our food distribution system has grown into something that we aren’t able to control completely.
At least that’s the testimony of the Salmonella map.