June 2009

 We wrote in May about the new, faster tests that are in the works for detecting botulism.  Sandy Miller Hays of the Agricultural Research Service picks up this subject in today’s Everybody’s Science. She writes:

Although cases of foodborne botulism are rare in the United States these days, they do still occur. Botulinum toxin occurs in seven different forms, known as serotypes A through G, although serotypes A and B are the culprits in about 90 percent of the foodborne botulism cases in the United States. (Botulism is the reason why your mother warned you to never, ever eat food from a can that’s dented, swollen or–heaven forbid–leaking.)

Botulinum is a protein that acts like a neurotoxin, interfering with the neurological system that otherwise transmits vital signals throughout your body. In particular, it can cut off normal messaging to muscles, causing paralysis. Worst-case scenario: The toxin paralyzes the muscles of your diaphragm and you die of suffocation.

Unfortunately, there is no federally approved vaccine against botulinum. An injection of horse antiserum can help remove the toxin from your bloodstream, but that treatment can cause serious side effects.

Its worth going to her site and reading the rest.

The Sea Harvest Restaurant of Carmel, CA is not a licensed cannery, but is recalling its canned cioppino sauce because there is a possibility it is contaminated with botulism.

The sauce was being canned by the Sea Harvest and sold as a retail product in the restaurant.

No illnesses have yet been associated with the recall.

The restaurant is cooperating with the California Department of Public Health and the Monterey County Health Department in the voluntary recall.

California officials said  Sea Harvest does not have the required cannery license to produce the cioppino sauce. 

We are very fortunate that while botulism is deadly it is also rare.

Today’s issue of Morbidity & Mortality Weekly Report (MMWR) published by the Centers for Disease Control & Prevention (CDC) carries an article that dissects all the food-borne disease outbreaks that occurred in 2006.

In “Surveillance for Foodborne Disease Outbreaks — United States, 2006;” CDC looks at all 1,270 Food-borne Disease Outbreak (FBDOs) that were reported during that year, resulting in 27,634 confirmed illnesses and 11 deaths.

Only one of the 11 deaths was from Clostridium botulinum or botulism. That fatality was attributed to the C. botulinum toxin being transmitted by carrot juice.

Writing on his personal blog last December, Seattle food safety attorney Bill Marler told us what happened:

"For those that do not recall, in September 2006, three people living in Georgia developed food-borne botulism that was eventually traced to commercial carrot juice from a single bottle. Soon thereafter an additional case in Florida and two in Ontario, Canada surfaced. One of the 6 botulism patients died 90 days after illness onset. One year later, two others were still on ventilators. The remaining three were taken off ventilator support after 54, 90, and 129 days. Two survivors were at home, two were in rehabilitation facilities, and one was still hospitalized. All the patients had consumed carrot juice from the same manufacturer.

"Now, here is the interesting part, according to Dr. Anandi N. Sheth at the Centers for Disease Control in Atlanta, Georgia and colleagues, an investigation eventually determined that inadequate refrigeration probably led to botulinum toxin production. As the investigators pointed out, the pasteurized carrot juice had no protection against the bacterium Clostridium botulinum other than refrigeration. "This investigation demonstrates that carrot juice and other processed foods with no natural barriers to C. botulinum germination require additional chemical or thermal barriers," the investigators wrote in the medical journal Clinical Infectious Diseases. Accordingly, they report, "In June 2007, the FDA modified its guidance for refrigerated low-acid juices to recommend adding a validated juice-treatment method, such as acidification or appropriate thermal treatment, to decrease the risk of C. botulinum contamination, should any breaches in refrigeration occur."

Its comforting to know FDA may have addressed the problem and implemented the fix for the 2006 carrot juice outbreak.  However, it also shows that botulism from food products remains a concern.


The deaths in April of a dozen horses on one pasture in Natrona County, WY were due to botulism. Over last weekend, KCWY-13, Wyoming’s NBC affiliate reported that:

Dr. George Marble says 3 horses were already dead on April 10th and when he went to the ranch he found two more that weren’t able to walk. Within two days, all twelve the of the rancher’s horses were dead or euthanized. Almost all the horses suffered paralysis of the legs and tongue which are both classic signs of botulism. The vet says no other pastures were affected by the toxin.

The veterinarian told KCWY-13, "the animals that were upstream so to speak from this particular pasture cause there was a little creek that ran through and those downstream from those horses and those that bordered on a fence line are all unaffected."

An equine health site associated with Horse Magazine says: "Horses usually become infected with botulism by ingesting the neurotoxin produced by the anaerobic bacterium Clostridium botulinum in contaminated feed or water. Feed contamination can occur when the decomposing carcass of a rodent or bird is baled in hay. This is seen more often in round bales. Feed can also be contaminated through improper storage or poor fermentation. Rarely, horses can get botulism when C. botulinum from the soil gets into an open wound."

KCWY-13 said it is extremely important for ranchers to check the hay before feeding, especially in the summer.