What is it? - There are about 2000 different forms of
bacteria in the genus Salmonella, all of which are considered pathogenic, or disease causing. This genus includes
S. typhi (which causes typhoid fever), S. choleraesius, and S. enteritidis, which are the most frequent causes of
salmonellosis, or Salmonella gastroenteritis. About 45,000-50,000 cases of salmonellosis are reported each year,
but the disease is thought to be underreported. An estimated 2-4 million cases likely occur each year, resulting in
about 500 deaths.*
What does Salmonella have to do with my iguana? - Many animals, including some reptiles, can carry Salmonella. In pet reptiles, the carriage rate is as high as 90%.* In some iguanas, Salmonella bacteria live in the intestine. These bacteria are shed with the feces and can be picked up by humans. A disease that can spread from animals to humans is called a zoonosis. Thankfully, your iguana can’t give you typhoid fever. That strain of Salmonella is transmitted only from person to person. However, your iguana may carry other forms of Salmonella that could cause you to experience salmonellosis.
How can I tell if my iguana carries Salmonella? - Unfortunately, you can’t. Many iguanas infected with Salmonella are not sick themselves. You cannot see the bacteria in the feces, and therefore have no way of telling if they are present or not. You can have your iguana tested for Salmonella by having your vet culture the bacteria from your iguana’s feces, but these results may not be reliable. Salmonella may be shed on and off periodically, which means that an iguana that tests negative at one time may be infectious sometime later. The best way to deal with Salmonella in your iguana is to assume that it is there, and act accordingly.
How can I get Salmonella from my iguana? - The most common mode of transmission from iguana to human occurs something like this: The iguana defecates and gets minute amounts of feces on itself - perhaps on the tail or foot. This problem is compounded if the iguana’s habitat is not kept clean. (See our page on Cleaning and Cleanliness.) The owner handles the iguana, or cleans up objects the iguana has climbed on or touched, and unknowingly gets the feces on his or her hands. The owner then proceeds to touch his or her mouth or prepare food without washing hands first.
What are the symptoms of salmonellosis? - Usually, an infected person experiences a moderate fever, nausea, abdominal pains and cramps, and diarrhea. Most healthy adults will recover in a few days without lasting effects. Thankfully, the overall death rate from salmonellosis is very low, probably less than 1%.* Salmonellosis can be deadly, however, in infants, the elderly and those with compromised immune systems.
How can I prevent the spread of Salmonella from my iguana? - The easiest thing you can do to prevent the spread of Salmonella is to practice good hygiene. Wash your hands after handling your iguana or anything your iguana has come into contact with. Keep your iguana and its habitat clean. Avoid allowing your iguana to come into contact with those who may be especially at risk, such as young children. If you are careful and use common sense, you can easily avoid getting Salmonella from your pet.
Note: Information on this page marked with an asterisk (*) was taken from Tortora, Funke & Case, 1998, Microbiology: An Introduction, Addison Wesley Longman Inc., Menlo Park, CA.
is a probiotic (living “good” bacteria) that can be given to iguanas
to help suppress the shedding of Salmonella bacteria.
Melissa Kaplan’s page on Salmonella
discusses many aspects of this bacteria’s occurrence in reptiles.