Bacteria illustrates Darwin's law

I've been following the news on the German E. coli epidemic, but still have a few questions. How likely is it to spread to New Zealand, or to occur here on its own? And how treatable is it? - TL
The outbreak in Germany involves enterohaemorrhagic ("gut-bleeding") E. coli, which as of the first week in June, had infected more than 2000 people and killed 22.
These bacteria normally live in the gut of around 1 per cent of cows, and spread to humans through undercooked mince, unpasteurised milk, or faecally contaminated produce, as appears to be the case in Germany.
The bacteria make it past the body's natural defences including stomach acid and white blood cells, and cross the intestinal wall into the bloodstream, where they spread widely. In most cases the symptoms are limited to abdominal cramping and bloody diarrhoea. But in perhaps a quarter of the German cases, a more serious condition developed: haemolytic-uremic syndrome (HUS). This occurs when bacterial toxins bind to and destroy kidney cells, provoking an immune reaction that causes out-of-control clotting and bleeding throughout the body. These patients can suffer kidney failure, strokes, and heart attacks. So far, about 5 per cent of the German HUS victims have died.
Unfortunately, there is no magic bullet treatment. Antibiotics in HUS can actually be dangerous, as dead bacteria may be free to release even more toxins than live ones.
The mainstay of treatment is to give people fluids by mouth or, if necessary, intravenously. If patients progress to severe disease, then dialysis, transfusions of blood cells or platelets as needed, and exchanging patient plasma with donor plasma are all options.
The risk of contagion is far lower than for measles or flu, as the route of transmission is faecal-oral rather than airborne droplets. Still, washing vegetables, even "ready-to-eat" ones like pre-packed salads and bean sprouts, is always a good idea.
Even briefly cooking food to 70C is enough to kill the bacteria.
As for whether it could happen here, outbreaks of one kind or another are the rule, not the exception. Natural selection ensures that we'll continually face "smarter" microbes despite our best treatments.
Gary Payinda MD is an emergency medicine consultant in Whangarei.
Have a science, health topic or question you'd like addressed? Email: drpayinda@gmail.com
(This column provides general information and is not a substitute for the medical advice of your personal doctor.)