Definition
Botulinum toxin is the most poisonous substance known to man. Even a small amount is lethal. It is produced by bacteria in the Clostridium genus. The US State Department reports that a number of countries that support terrorism are developing or have the toxin as a germ-warfare weapon. Some terrorists have tried attacks using botulinum toxin produced from bacterial spores found in the dirt. As a weapon, the toxin might be released in the air or placed in the food supply. The toxin causes the disease botulism. In tiny doses, the toxin is injected as a treatment for eyelid muscle spasms, migraine headaches, and other conditions.
Causes
Botulinum toxin poses a great threat. It is easy to produce and transport. Only one gram of the toxin evenly released and inhaled could kill one million people. However, it is hard to keep stable for release in the air. Some experts believe it would not work in stopping a military enemy. US troops receive a botulinum toxoid vaccine to prevent the disease if exposed to the toxin. But release of the toxin in a civilian population would present serious results. Botulinum toxin is colorless and odorless. The toxin cannot be passed from one person to another.
Risk Factors
A risk factor is something that increases your chance of getting a disease or condition.
• Exposure to the toxin after its release during a biological terrorism attack
• Rarely, accidental exposure to the toxin may occur as a result of food contamination, especially if the contaminated food was not packaged properly or was served undercooked (heat destroys the toxin)
Symptoms
Experts predict symptoms from an airborne bioterrorism attack would begin 12–72 hours after exposure. Symptoms from a food attack could start within two hours or as long as eight days after eating food with the toxin. Severity and speed of onset might vary depending on the amount of toxin absorbed.
Symptoms include:
• Double or blurred vision
• Trouble swallowing
• Difficulty speaking
• Weakness in clenching jaw
• Droopy eyelids
• Loss of head control
• Weakness, on both sides, starting at the head and working down the body
• Constipation
• Paralysis
Diagnosis
The doctor will ask about your symptoms, medical history, and possible source of exposure, and perform a physical exam. Expect to answer questions about where you have been and what you have eaten. Blood, stool, and stomach contents will be tested for the toxin. Samples of questionable food may also be tested. Other cases in the area may alert healthcare workers to the possibility of a bio-terrorism attack. Special tests to confirm a diagnosis take days to complete.
Tests to rule out other medical conditions may include:
• MRI scans – tests that uses magnetic waves to make pictures of tissue inside the body
• Spinal fluid analysis
• Electromyogram and nerve conduction tests
Treatment
Early therapy with an antitoxin is essential to decrease resulting nerve damage. Treatment should start without waiting for confirming diagnostic test results.
Antitoxin
If started early, an antitoxin can stop the paralysis from progressing and may shorten symptoms. It does not reverse the disease process.
Supportive care
The most serious complication is respiratory failure. Treatment aims to maintain adequate oxygen supply. Patients may require a ventilator and close monitoring in an intensive care unit. Feeding through a tube also may be needed. Recovery occurs after the body produces new nerve fibers. This process may take weeks or months.
Public health measures
Cases are reported to public health officials. Contaminated clothing and surfaces should be washed with a bleach solution or left untouched for days.
Ridding the body of ingested toxins
Methods to eliminate the toxin include:
• Enemas
• Suctioning of stomach contents
• Medication to stimulate vomiting
Prevention
Antitoxin could be given after a known release of the toxin. But there are limited supplies of antitoxin. In the event of a terrorism attack, the antitoxin likely would be given to patients at the first signs of illness.
Laboratory workers and military personnel can receive a toxoid vaccine to prevent the disease by building immunity. As stated in the Journal of the American Medical Association, the botulinum antitoxin is available from the Centers of Disease Control and Prevention (CDC) through state and local health departments.
There would be no warning systems to alert authorities that the toxin had been released. The success of an attack would depend on its secrecy, the size of the toxin particle, and weather conditions at the time of release. If aware of an attack, covering your mouth and nose with clothing or a hankie might offer some protection. Experts predict some of the released toxin could live in dry, cool air for up to two days.
Botulinium toxin in food or drink can be inactivated by heating to 85°C (185°F) for at least five minutes.
Botulinium toxin is also degraded under general environmental conditions. Exposed objects can be decontaminated by washing them with a 0.5% sodium hypochlorite solution (bleach).
