Salmonella and E.coli

Salmonella:

Get this - In 1996 1994 (thanks Kris for the fact check) 224,000 people in the united states were infected with Salmonella enteritidis after eating Schwan's ice cream (I'm glad I've never heard of that brand)! Why did this happen? Well, take note that Salmonella is commonly found on chickens (estimates reach nearly 80% for chickens infected with Salmonella, or Campylobacter), and that ice cream contains eggs. Now, Schwan's Ice cream making process, as far as eggs go, involves three factories:

1) an egg breaking plant: makes liquid egg
2) a processing plant: makes an ice cream pre-mix using the liquid egg from factory "1" and pasteurizes said mix.
3) The final Ice cream making plant: makes ice cream.

Unfortunately, in order to increase efficiency, Schwan's decided to use the same trucks that transported liquid egg from plant "1" to plant "2," to transport the pasteurized pre-mix from plant "2" to plant "3." Not a bad idea, but apparently nobody told the truck drivers to clean out their tankers before transporting the pre-mix, effectively nullifying pasteurization... DOH! From the New England Journal of Medicine, "Written procedures called for the washing of tanker trailers after the delivery of liquid eggs and specified that the interior of the tanker trailer was to be washed and sanitized and the outlet valve removed for hand cleaning plus sanitization before premix was loaded. Officials of the FDA and the Minnesota Department of Agriculture noted soiled outlet-valve gaskets, inadequate record keeping, and the lack of routine inspection of the interior of the tanker trailer." I guess that's how to get a quarter million people sick with dysentery.

E. coli:

Ever wonder why you should always get your burger "Well done?" E. Coli is present on the surface of meats, so when you cook a steak, in order to kill E. coli, you only really need to thoroughly cook the surface. The problem with ground beef is that you take that bacteria, originally just on the surface, and mix it all up inside the meat. So, don't eat pink burgers!

Jack in the Box learned this the hard way... A rare and particularly virulent form of E. coli (serotype O157:H7) happened to find it's way into their undercooked burgers, infecting 47 people. This is the same serotype of E. coli that caused the recent spinach scare. E. coli O157:H7 (a.k.a. EHEC for EnteroHemorrhagic E. Coli) is the main cause of Haemolytic-uremic syndrom, the main cause if kidney failure in children.

To see a cool video on how EHEC infects a cell go to: http://www.hhmi.org/biointeractive/disease/animations.html
scroll down and click on E. coli infection strategy. And while you're there, check out all the other cool videos about such topics as; Horizontal gene transfer "Bacterial conjugation" (as discussed in a previous post on antibiotic resistance), viral life cycle, recombination of viral genome, and HIV life cycle.