Anthrax And Agriculture: Risks Of Anthrax Infection In Livestock

Anthrax disease is caused by a bacterium known as Bacillus anthracis. It is an infectious disease that spreads from animals to humans through the spores of the bacteria. It mainly affects livestocks and can be potentially life-threatening.¹ Treatment of anthrax involves the use of antibiotics and vaccination for individuals at risk.²

What is anthrax disease?

Anthrax is an infectious disease that occurs in both humans and animals. It is caused by a spore-forming bacteria called Bacillus anthracis. It commonly affects livestock, where and it spreads to agricultural workers and veterinarians.³ 

How does anthrax spread?

Anthrax spreads through the spores produced by the bacteria. These spores contain toxins that are responsible for their virulence.⁴ 

The spores remain in the soil for a long time and are very resistant. They live for about five years in the surface soil and much longer in the deeper soil. Wet weather and tilling of soil bring them to the surface. 

Animals commonly affected by anthrax are herbivores, mainly cattle and sheep. Dogs and cats also get the disease on contact with infected blood from the dead animals. Most of the birds are resistant to anthrax due to their high body temperature. Swine, horses, as well as humans are less susceptible to anthrax compared to sheep and cattle.⁷

People get the infection when they come in contact with an infected animal or animal products that contain the spores.³

What are the different forms of anthrax disease?

There are different forms of the disease depending on how the bacteria enters the body. Bacillus anthracis enters the body through the skin, lungs, or gastrointestinal tract.⁵

Cutaneous form

The bacteria requires a lesion to cause the disease. Spores enter a person's body through any scratches or cuts, causing infection. If not controlled, the disease may spread throughout the body. 

Inhalational form

Anthrax spores also enter the body through inhalation. This can even lead to death of the animal. It is also called wool sorter's disease.³

Gastrointestinal form

Spores of the bacteria are ingested from raw and undercooked meat of infected animals. The bacteria can affect the digestive tract anywhere from throat to the intestines, resulting in a variety of symptoms.⁵

How does anthrax affect agriculture?

Anthrax can occur in acute and subacute forms. 

Acute type

In the acute form of the disease, animals show signs of high fever, breathing difficulty, and muscle tremors. This may be followed by the sudden collapse and death of the animal. The blood does not clot and exudes from the body. The animal’s body does not stiffen.

Subacute type

The subacute form of anthrax disease is characterized by a fever that slowly progresses to weakness and loss of appetite, depression, a state of prostration, and finally death.

Symptoms like stomach upset, fever, colic, swellings, and depression may occur for about four days before the death of the ruminant. Carnivorous animals may feed on the infected meat and develop fever and muscle cramps. Symptoms are not severe and the animals survive in most of the cases.³

What are the signs and symptoms of anthrax disease?

Symptoms of anthrax mostly develop within 6 days after exposure to the spores. It may take time for the symptoms to start appearing in the inhalational form of anthrax. The symptoms present vary according to the type of infection. 

Cutaneous form

Cutaneous form is the most common type of anthrax. Symptoms in cutaneous anthrax are mild. They include:

• An itchy and raised bump progresses to an ulcer with a black center, which is often painless
• Fever 
• Headache
• Swelling of lymph nodes

Gastrointestinal form

Eating anthrax infected meat affects the gastrointestinal tract causing symptoms like:

• Vomiting of blood
• Nausea
• Stomach pain
• Loss of appetite
• Sore throat
• Fever
• Headache
• Bloody diarrhea⁶

Inhalational form

Inhalational form of anthrax is the deadliest and can be fatal. There is a 75% death rate associated with this form of the disease.² Symptoms include:

• Initial episode of fever, sore throat, and fatigue.
• Breathing difficulty 
• Bloody cough
• Chest discomfort 
• Difficulty swallowing
• Meningitis
• Shock leading to circulatory collapse

Injection form

Anthrax disease may also spread through the injection of illegal drugs causing symptoms like:

• Swelling
• Redness
• Shock
• Meningitis
• Organ failure

How is anthrax diagnosed?

Diagnosis of anthrax disease involves the following procedures:

1. Blood tests
2. Stool and mucus examination
3. Biopsy of the cutaneous lesion
4. CT scan
5. Chest X-ray
6. Lumbar puncture

How is anthrax treated?

Prophylactic treatment is initially given to those who have been suspected of exposure to anthrax spores. Treatment involves the use of antibiotics medication and antitoxins.^1,6

Antibiotics

Antibiotics can be taken through oral or intravenous routes. Commonly used antibiotics are:

• Doxycycline 
• Ciprofloxacin

Antitoxins

Antitoxins are medications containing antibodies injected to neutralize the anthrax toxins.

Is there a vaccine for anthrax disease?

Vaccines against anthrax are available for both animals and humans.

Anthrax in livestock is controlled by vaccinating animals using veterinary vaccines. 

Vaccines for humans are limited. They are provided mostly for individuals with occupational hazards and suspected of exposure to anthrax spores.⁶

A vaccine called BioThrax is given to prevent anthrax in people who are at a higher risk for anthrax exposure. It is given in 3 doses over a period of 4 weeks.¹

How can you prevent anthrax?

Proper control of the disease in animals can prevent its spread to humans. Source of the anthrax infection must be identified and eliminated as early as possible. 

Control measures include proper disposal of animal carcasses along with sterilization of the site and the instruments used in the disposal of carcasses. Incineration is the best method for disposal. This is because incineration provides a closed environment which prevents the exposure of carcasses to oxygen and the subsequent formation of spores.³

Animals should be vaccinated if they have been suspected of anthrax exposure.

Proper quarantine of the area and sanitation of dairy factories can prevent the spread of anthrax to humans and other livestocks.⁶

FAQs

What are the effects of anthrax on animals?

Animals affected with anthrax show signs of fever, swellings, breathing difficulty, loss of appetite, and muscle tremors. This may be followed by sudden collapse and death of the animal.

What is anthrax disease?

Anthrax is a disease that occurs due to a bacterial infection. It commonly affects the livestocks from where it spreads to humans.

How to treat anthrax in livestock?

Anthrax in animals is treated using antibiotics, antitoxins, and veterinary vaccines.

Summary

Anthrax is a bacterial infection that occurs commonly in animals. Humans get the disease due to ingestion of infected animal products or on exposure to the spores of the bacteria. Symptoms include fever, vomiting, breathing difficulty, sore throat, and swelling of the infected area. Anthrax is fatal in animals and may lead to sudden collapse followed by death of the animal. It can be treated by antibiotics, antitoxins, and vaccination. Proper disposal of carcasses and sanitation of facilities are essential to prevent further spread of the disease.