Definition Botulism is a condition caused by a toxin made by bacteria called Clostridium botulinum. This toxin triggers sudden, progressive weakness and paralysis. Infant botulism is usually seen in babies younger than 6 months old.
What is going on in the body? In adults, botulism occurs after eating the full-blown toxin. In infants, spores from the dangerous bacteria can grow in the gut and produce toxins. The spores settle in a baby's intestines. Once there, they mature and release toxins.
These toxins enter the blood stream and are carried to the ends of the nerves that control muscles. They block the release of a chemical called acetylcholine that transmits signals from nerves to muscles. If this chemical is not released at the proper time, the muscle cannot contract. This causes muscle weakness or paralysis.
The diaphragm is a strong layer of muscle below the lungs. If nerves in the diaphragm are blocked, the baby will not be able to breathe. If untreated, this can cause death.
What are the signs and symptoms of the infection? Usually, symptoms start 12 to 36 hours after the bacteria spores enter the body. It can take just a few hours, though, or as long as a week. The symptoms include:
constipation as muscles in the gut stop working properly
loss of the gag reflex and other nervous system problems
worsening paralysis of the muscles of the body
respiratory failure, or inability to breathe
What are the causes and risks of the infection? The Clostridium botulinum bacteria is one of the most poisonous substances known to man. Just a small amount of the toxin it produces can be fatal. Some sources of the bacteria and its toxins include:
honey, which should never be fed to babies younger than 12 months old
soil, which can infect a wound
canned or home-preserved foods that were not cooked enough to destroy the spores
What can be done to prevent the infection? To keep babies safe:
honey should not be given in a bottle, on a nipple, or in any other way to infants under one year of age
soil should not be allowed to contaminate the belly button before the cord stub falls off at around 2 weeks of age
food should be handled and prepared carefully
canned goods should not be eaten if the can is not swollen or the safety button on the lid had popped up before the lid was opened. Food safety cannot be judged by appearance. Food may not taste or look spoiled even if the toxin is present.
Although the toxin may be killed by heat, botulinum spores are heat-resistant. Boiling foods for 10 minutes or heating at 176°F to 212°F for 30 minutes before eating will destroy the toxin. Only high temperatures obtained in a pressure cooker can destroy bacterial spores in food. All low-acid foods must be canned in a pressure canner at 240°F (115.6°C) to destroy botulism spores.
Commercially canned foods rarely are responsible for botulism. But when sealed foods are not processed at high enough temperatures to kill the organism, the toxin and spores can thrive in the sealed container. The bacteria do not need oxygen to survive.
How is the infection diagnosed? Diagnosis includes a thorough examination by a doctor. The diagnosis can be made based on the signs and symptoms the infant is having. It is important to give the doctor information on any possible exposures. Tests to confirm the diagnosis include the following:
a stool sample test to check for the bacteria
testing of the food that may have caused the botulism
an electromyogram, or EMG, which may show signs of abnormal muscle function. An EMG is a study of how the muscles respond to electrical stimulation.
What are the long-term effects of the infection? When botulism is not treated, the death rate is very high. In recent years, it has decreased among adults due to the development of an antitoxin.
If a baby survives the first few days after botulism has been diagnosed and treated, recovery is usually complete. If serious respiratory paralysis occurs, this condition may be fatal.
What are the risks to others? This illness does not spread from one person to another. However, tainted food or soil may affect others.
What are the treatments for the infection? Treatment of infant botulism includes:
hospitalisation
supportive measures, such as bed rest, fluids given through a vein, comforting the infant and family
special enemas, which may be used to clear out the spores in the intestinal tract
It is not clear whether antitoxin can help in infant botulism.
What are the side effects of the treatments? Side effects vary depending on the treatment used. Penicillin can cause stomach upset and allergic reactions. Before the botulism antitoxin is given, a doctor may order a skin test to make sure the baby does not have an allergy to the antitoxin.
What happens after treatment for the infection? Once a baby has been treated and symptoms have subsided, no further treatment is needed. If a baby survives the first few days of botulism, symptoms subside over many months. Recovery is usually complete. If necessary, physiotherapy or occupational therapy may be used to help a baby recover muscle function.
How is the infection monitored? A doctor may monitor the baby closely over the first few months while symptoms of botulism disappear. The baby's ability to breathe properly and muscle control will be watched closely.
Author: Eileen McLaughlin, RN, BSN Reviewer: eknowhow Medical Review Panel Editor: Dr John Hearne Last Updated: 7/1/2005 Contributors Potential conflict of interest information for reviewers available on request
