Anthrax in Dogs

Anthrax infection in dogs is rare; if infected your dog can experience significant breathing difficulties and sudden death or develop a more chronic form where they feel vague symptoms of illness. In the chronic form, it will appear that something is not right with your dog. Should your dog be infected with anthrax, it is important to take proper precautions.

Infection with the bacteria Bacillus antracis leads to the disease Anthrax. Infection can lead to sudden death or a more chronic form with vague symptoms of illness.

When an animal is infected with anthrax, the most common sign is sudden death. Infection can be respiratory or intestinal; other symptoms of anthrax infection include:

• Fever
• Muscle tremors
• Breathing difficulties
• Lack of coordination
• Vomiting
• Diarrhea
• Convulsions

Should the anthrax infection result in death there may be bleeding from the mouth, nose and anus post mortem.

Types 

If Bacillus anthracis bacteria is ingested by your dog it could lead to sudden and severe poisoning of his blood. In this acute form, rapid swelling of the throat can occur which will lead to sudden death. 

A chronic form of anthrax is seen more often in dogs, where they display general signs of illness and slowly recover once they are undergoing treatment.

The bacteria Bacillus anthracis cause the disease Anthrax. The bacteria develop spores that make it resistant to conditions that normally destroy other bacteria (heating, freezing, dehydration or chemical disinfection). This leads to an environment being contaminated for a great length of time. Anthrax occurs most often in hoofed animals (cattle, sheep, goats, camels, antelopes) when they ingest the spores while grazing. 

While anthrax is rare in dogs, should your dog be infected it is most likely due to eating raw or undercooked meat that has been contaminated with the bacteria, or having had contact with the blood, tissues, or fluids of other animals that host spores. Dogs are typically very resistant to becoming infected with anthrax by inhaling spores and there is little concern regarding your dog developing the skin form of anthrax that can infect humans.

Should your dog be exposed to the bacteria, the average incubation period is 3-7 days. The bacteria will multiply and disperse within your dog’s body through blood and the immune system. A very strong, lethal toxin is created which will lead to cell death and breakdown of infected tissues, causing inflammation, organ damage and ultimately, organ failure.

If you notice signs of illness in your dog, you will want to bring him to your veterinarian immediately. Your veterinarian will inquire as to the symptoms your dog has experienced and will try to ascertain whether your dog may have eaten infected meat or come into contact with infected blood, tissue or fluids. In cases of anthrax infection, diagnosis can be challenging because symptoms will be similar to those of other conditions. Your veterinarian will require blood samples from your dog that can be analyzed to confirm that Bacillus anthracis bacteria is present. The following tests can be used to determine if the bacteria has infected the blood or tissue:

• PCR test
• A bacterial culture PCR test
• Fluorescent antibody stains 

Western blot and ELISA tests are available in some reference laboratories that can detect antibodies to anthrax. Loeffler’s or McFadyean stains can be used to stain blood smears; however, these can result in about 20% of false positives.

It is imperative that treatment begin as soon as possible as the course of anthrax infection is quick. The following antibiotics have been proven effective in treating anthrax:

• Ciprofloxacin
• Doxycycline
• Amoxicillin

Supportive treatment if necessary will be provided in the clinic in the form of intravenous fluids, medications for symptoms such as tremors or vomiting, and oxygen to assist with breathing if your pet is experiencing difficulties. Monitoring of your dog’s condition will be ongoing until it is determined that he is out of danger.

Should your dog be diagnosed with anthrax and be undergoing treatment, you will want to quarantine him so that the infection does not spread to any other animals or people. Anthrax spores are hard to eliminate, so rather than cleaning and disinfecting bedding or toys, it may be best to replace them. You will want to decontaminate your dog’s fur by bathing him often (no chemicals that kill spores are safe for animals) so that he does not transmit the infection through the spores to you or any other members of your household. You will want to check with health officials on how to decontaminate furniture or other household items. When working on decontaminating your dog and your environment, you will want to take appropriate precautions to avoid infection; this includes wearing gloves, protective clothes, goggles, and masks.