What is bovine anthrax? How to respond after cattle are infected

In the process of raising livestock, anthrax is a relatively common disease. Not only are animals susceptible to infection, but the humans who tend them may also become infected. Let us take a look below at what anthrax is and what to do if cattle get it.

1. What is anthrax?

According to experts, anthrax is an acute, febrile, septic zoonotic disease caused by Bacillus anthracis. China classifies it as a Class II animal disease, the Law of the People's Republic of China on the Prevention and Control of Infectious Diseases classifies it as a Class B infectious disease, and the World Organisation for Animal Health (OIE) lists it as a notifiable animal disease.

Bacillus anthracis has very strong vitality. It not only grows and reproduces easily, but also has a self-protective function: it forms a capsule on the outside of the bacterium, as if the bacterium has put on armor, which can resist the attack and phagocytosis of immune cells. Under certain conditions, a small part inside this bacterium becomes concentrated and forms a hard “spore”, making it resistant to high temperatures, resistant to drying, and not destroyed by ordinary disinfectants, lying dormant in the soil for as long as 40-50 years without dying; once conditions are suitable, the bacterium inside the spore will grow out like “sprouting”, becoming a bacterium capable of reproduction again.

Anthrax is a global zoonotic disease, with about 20,000-100,000 cases each year. It occurs in Europe, Asia, Africa, the Americas and Oceania. In China, anthrax outbreaks are mainly concentrated in some provinces in the northwest, southwest and northeast. Outbreaks can occur in all four seasons, with the peak incidence from June to September each year, and drought and flooding are the main triggers.

Humans and animals are mainly infected through the digestive tract, and can also be infected through the respiratory tract or contact with damaged skin. Contaminated soil, water sources and sites can form persistent epidemic foci. In most cases, cattle, sheep and other herbivores become infected by ingesting spores while grazing, and humans become infected by contact with the meat, fur, blood of infected livestock or other contaminants such as soil. Contact with healthy cattle, sheep and other animals and their meat products will not cause anthrax infection.

2. What should be done if cattle get anthrax?

1. Maintain good barn hygiene and promptly remove sources of infection (manure, bedding, leftover feed, walls and ceilings, etc.). Removing sources of contamination is the basis for reducing transmission through respiration;

2. When sick cattle need to be handled, it is recommended to wear masks, gloves and other necessary protective equipment to avoid zoonotic infection. For some relatively serious diseases, under the premise of not being fully prepared, be sure not to perform necropsies at will;

3. For ground cleaning outside the barn, especially stagnant water pits and manure accumulation areas that easily breed bacteria, parasites and viruses, carry out disinfection and sterilization measures for barn entry and exit where conditions permit;

4. Follow-up handling: for dead and diseased animals, it is recommended to use burial (quicklime should be spread both above and below the burial pit to avoid contaminating groundwater); for contaminated animal manure, it is recommended to use the stacked bio-thermal fermentation method.

5. Immunization: in areas where anthrax has occurred, inject anthrax No. 2 spore vaccine subcutaneously once a year;

6. Isolation, blockade and disinfection: when a disease outbreak occurs, immediately blockade the affected site and promptly report it to the local veterinary department. The carcasses of diseased cattle, as well as manure, bedding and other waste, should be incinerated or deeply buried, and the burial site should be far from water sources, roads and pastures. Barns, sites and tools contaminated by diseased cattle and sheep should be disinfected with a 20% bleaching powder solution or a 0.2% mercuric chloride solution.