Yesterday it was announced that a dairy cow in California tested positive for bovine spongiform encephalopathy (BSE) also known ubiquitously as mad cow disease. It was the 4th cow in the U.S. to test positive. Two months ago two Californians were found to have Creutzfeldt-Jakob disease – another type of Transmissible spongiform encephalopathies. Neither of these cases are thought to have been caused by eating infected cattle.
Mad cow is a nasty disease that basically makes the brain into swiss cheese and it can be passed on through eating a sick animal. When humans eat an infected cow they can develop variant Creutzfeldt-Jakob disease (vCJD). Both are caused by errant proteins called prions. Unfortunately heat doesn’t destroy the prions so even eating cooked meat won’t make it safe. What’s even scarier is that it can take up to 10 years before you show symptoms of being sick. By then who knows how many other people could have been infected considering one cow can be spread across thousands of products.
The cow found in California is said to have had atypical BSE which means it *probably* didn’t get it through feed and since it didn’t enter the food system we won’t have to worry about that specific cow sickening hundreds or even thousands of people. However, only 1,000-2,000 animals a year are tested for this disease so finding this one was simply a stroke of luck.
The first cow back in 2003 to be infected with BSE actually entered our food system. Fortunately the beef was recalled in time before people ate it. The second cow was from Texas. Most of the cows from the herd that #2 came from were slaughtered and had already entered our food system. In addition proper records were not kept on the animals and so many became untraceable. The third cow’s herd was never found.
What has made BSE such a problem is that we are feeding ruminants food they aren’t meant to eat – other ruminants. The mad cow outbreak in the UK likely started when a cow with a spontaneous form of BSE or a scrapie-infected sheep was processed into cattle feed. One animal – that’s all it took to infect 184,500 animals in the UK through to 2010. Why in the world are we even thinking about feeding animals to herbivores though? That’s the big question here.
The US finally decided to create an enhanced feed ban in 2009 that simply bans mammals to be fed to ruminants and that the brains and spinal cords of animals over 30 months of age will not be used for any feed whatsoever. As stated earlier it can take up to 10 years for BSE to show itself so there may still be animals out there that are infected.
I can’t say this enough. Know your farmer and only eat grass fed and finished beef.