Foodborne illness (also referred to as food poisoning) causes symptoms that range from general discomfort to the possibly of life-threatening illness. On a scale of severity, foodborne botulism is quite possibly the most dangerous variation of food poisoning in existence.

What is botulism?

Clostridium botulinum | Image courtesy Phil Moyer | Flickr

The Centers for Disease Control and Prevention (CDC) defines botulism as: “a rare but serious paralytic illness caused by a nerve toxin that is produced by the bacterium Clostridium botulinum and sometimes by strains of Clostridium butyricum and Clostridium baratii.”

Foodborne botulism is contracted by consuming foods contaminated by the botulism toxin. Without medical attention, foodborne botulism is a potentially deadly illness. All instances of foodborne botulism are considered a public health emergency, as the risk of widespread illness from a common food source is disproportionately high.

The early symptoms of botulism include severe weakness, fatigue, and vertigo. Difficulty swallowing and speaking, dry mouth, and blurred vision are also reported early symptoms. The paralytic properties of botulism toxin include progressive weakness and numbness in the arms and neck as well as difficulty breathing.

In most instances, symptoms of botulism appear within 12 to 36 hours of the consumption of contaminated food. Without proper medical intervention, including the administration of an antitoxin, the toxin’s paralytic properties can cause respiratory failure and eventual death. Statistics reveal that 5 to 10 percent of all foodborne botulism cases today result in the death of the victim. However, prior to the advent of many now-common medical practices, upwards of 50 percent of all botulism cases ended in death.

Cases of botulism are very rare, with an average of 145 cases being reported annually. Roughly 15 percent of these cases originate from contaminated foods, 65 percent are instances of infant botulism, and 20 percent are from wound-based contamination. It is noteworthy that outbreaks of foodborne botulism that involve more than one individual are usually the result of consuming contaminated, home-canned foods.

Diagnosis and Treatment of Botulism

Diagnosing foodborne botulism commonly involves a process of deduction. Generally, the symptoms of botulism are quite similar to those of other diseases, illnesses, and medical events or emergencies. For example, Guillain-Barre syndrome — a disease in which the immune system attacks parts of the peripheral nervous system — can mirror many of the adverse effects of botulism, including progressive weakness and difficulty breathing. Stroke and heart attack, along with other cardiovascular and neurological variables, are often ruled out before a diagnosis of foodborne botulism is made.

Additional tests, including a brain scan, electromyography and spinal fluid examination may be conducted as a precautionary measure and/or to obtain supplementary evidence to support a diagnosis. Ultimately, the treatment methodology varies between physicians, but the practice of eliminating other potential causes for the symptoms being experienced is common. In rare instances, tests for botulism toxin may be undertaken at a health department laboratory.

As foodborne botulism is a medical emergency, immediate treatment is necessary. The subsequent respiratory failure and paralysis can cause death if treatment is not administered. In severe cases, victims may be placed on a ventilator or similar breathing apparatus while they undergo intensive treatment, often for a prolonged period of time.

Provided medical attention is administered promptly, paralysis symptoms gradually reside. To eradicate the remaining toxins, the tending physician may induce vomiting or conduct an enema. Attentive and competent care in a qualified medical facility is paramount to the successful treatment of foodborne botulism.

Prevention of Botulism

The vast majority of foodborne illnesses can be prevented, including botulism. Since many foodborne cases of botulism originate from home-canned food, the practice of appropriate canning techniques can aid in the reduction of the number of botulism cases.

canned fishOf the different varieties of canned foods, certain types unquestionably carry a higher risk for contamination with botulism. Foods with low acidity levels, such as asparagus, beets, corn, and green beans, have accounted for more cases of home-canned foodborne botulism than any other type.

For those that home-can foods, knowledge and practice of proper canning techniques is invaluable to reducing the risk of foodborne illness. Pressure canners and other canning equipment should be used with an understanding of the operation of such products.

In certain areas of the United States, foodborne botulism sources include fermented fish and other types of water game. A fundamental rule is to monitor current events for any adverse health news related to such foods. Abstaining from the consumption of certain fish, particularly if raw, as well as certain types of game can further limit the odds of contracting foodborne illness, including foodborne botulism.

The application of high temperatures through heating and/or cooking is important in minimizing the likelihood of contracting foodborne botulism, as botulism toxin is eradicated at such temperatures. The CDC strongly recommends boiling home-canned foods for approximately 10 minutes to ensure safe consumption. Cooking any type of prepared food thoroughly and at elevated temperatures is fundamental to preventing foodborne illness, including botulism.

Food safety measures, including the prevention of foodborne illnesses, have demanded the attention of public officials. As such, resources allocated to the prevention, investigation, and resolution of food safety issues such as foodborne botulism have assisted in efforts to help ease public health concerns.