Armadillos are unique mammals with armor-like shells, primarily found in Central and South America. The nine-banded armadillo has expanded its range into the southern United States. While they can carry pathogens, the overall risk of disease transmission to humans is generally low.
Armadillos and Leprosy
Armadillos have a unique association with Mycobacterium leprae, the bacterium responsible for leprosy (Hansen’s disease). The nine-banded armadillo is one of few animals, besides humans, known to host this bacterium. Partly due to the armadillo’s lower internal body temperature (32-35°C / 90-95°F), this environment is optimal for bacterial growth.
Transmission of M. leprae from armadillos to humans occurs through direct, prolonged contact with an infected animal, such as handling or consuming its meat. Up to 20% of armadillo populations in some areas may carry the bacterium. While human-to-human transmission accounts for most global leprosy cases, armadillos are a known source for some U.S. cases, particularly in Florida, Texas, and Louisiana.
Leprosy primarily affects the nerves, skin, and upper respiratory tract, causing skin lesions, numbness, and muscle weakness. Symptoms take years to appear, with an average incubation period of five years, sometimes up to 20 years or more. Early diagnosis and multidrug therapy are important to prevent permanent damage.
Other Diseases Armadillos Can Carry
Beyond leprosy, armadillos can carry other pathogens. They are known to harbor Salmonella bacteria, transmissible through their feces. Contact with contaminated soil or food can cause salmonellosis in humans, with symptoms like fever, diarrhea, and abdominal cramps.
Armadillos can harbor Trypanosoma cruzi, the Chagas disease parasite, though direct transmission to humans is uncommon. While rare, armadillos can carry the rabies virus, but they are not primary carriers. Other potential pathogens include Giardia, tapeworms, and fungi like Histoplasma capsulatum, which can cause histoplasmosis.
How Diseases are Transmitted and Prevention
Diseases from armadillos transmit to humans through direct contact with an infected animal or indirect exposure to contaminated environments. Indirect exposure occurs if individuals contact soil, water, or surfaces contaminated with armadillo feces, saliva, or bodily fluids.
Preventive measures minimize exposure risks. Avoiding direct physical contact with armadillos is the most effective way to prevent transmission, even if the animal appears docile. If contact is unavoidable, such as during animal removal, wear sturdy gloves and thoroughly wash hands with soap and water afterward. Avoid consuming armadillo meat and educate children about observing wildlife from a safe distance.
Maintain good hygiene, especially after gardening or outdoor activities in areas where armadillos are present, to prevent exposure to contaminated soil. Securing properties with fences that extend below ground can deter armadillos from burrowing and reduce contamination. Report sick or unusually behaving armadillos to local wildlife authorities.
Assessing the Overall Risk
While armadillos can carry various pathogens, including the leprosy bacterium, the overall risk of disease transmission to the human population is low. Transmission requires specific conditions, such as prolonged or direct contact with an infected animal or its contaminated environment. Most people are not genetically susceptible to leprosy, further reducing the risk even upon exposure.
For individuals with direct armadillo contact or suspected exposure who develop unusual symptoms like skin lesions or numbness, consulting a medical professional is advisable. Prompt medical evaluation can lead to early diagnosis and effective treatment, preventing complications.