Anthrax is preventable if stock farmers take a proactive and responsible approach to disease monitoring and control.
This is a disease that comes with loss guarantees: loss of animals; loss of income, including potential export revenue; loss of small and medium businesses and a potential threat to human life.
So, if you live in an area where there have been reports, rumours or even rumours of rumours, of anthrax, get out into your herd or flock now. Check, block and vaccinate your livestock right away.
Anthrax is a soil-dwelling, spore-forming bacterium; tough and resilient, it can survive long periods of dormancy. Any event within the previous seven years is a signal for stock farmers to put the anthrax vaccination and booster into their annual ‘must-do’ vaccine list.
When the weather changes from dry and cool to hot and wet, and animals trample areas around water points, or farmers deep rip their lands, the scene is set for the perfect anthrax storm.
Once the spores emerge from the soil and make contact with oxygen, the bacilli (bacteria) are released and activated.
Bacillus anthracis, is a highly infectious and fatal strain of anthrax that infects via the spores. An infected carcass, once opened, can release thousands of spores into the air and infect a great number of other animals.
Ruminants (including cattle, sheep and goats and certain game animals) are particularly susceptible to anthrax, but other herbivores like horses (hindgut fermenters) are also at risk.
Anthrax can infect pigs and carnivores but they usually recover, although pigs may die if septicaemia sets in.
Carnivores (including dogs) suffer from intestinal cramping and fever with anthrax, but recover fully once treated with penicillin. Be vigilant about keeping dogs away from dead animals because they may puncture the carcass and in this way release spores.
Rapid death with no warning
Anthrax is generally asymptomatic (without symptoms) although some cases show symptoms shortly before death. In cattle and sheep, once the stockman has noticed the high temperature, staggering, trembling, breathing difficulties, convulsions and collapse, it’s far too late to treat, and death will generally follow in two to three hours.
In horses, there are symptoms of fever, chills, colic, anorexia, depression, weakness and bloody diarrhoea for two to three days before the animal succumbs.
Anthrax is a zoonotic disease and will kill humans as well as animals, if it is not treated. In humans it usually starts with a skin infection. The pathogen enters the body through a cut or lesion unless it is inhaled.
Common pathways of animal infection are eating contaminated soil, contaminated grazing or bagged feed, or spore inhalation.
The anthrax bacteria produces lethal toxins that cause necrosis (tissue death) and extensive edema (fluid accumulation). As the bacteria reproduce in the body, the toxic effects increase, more tissue is destroyed and ultimately there is organ failure. The incubation period is between three and seven days.
Pay attention and act
To stay on top of an anthrax outbreak, farmers must be aware. Ignorance is no excuse, waiting for the state to mobilise is not always sensible.
The state herds are not going to die – yours are. With anthrax around, don’t wait; act and stay ahead of the disease.
Never open the carcass of a suspected anthrax-infected animal. If you have seen any of the signs, and the rapid death follow up, do not touch the animal. Once the spores inside the carcass are released and exposed to oxygen, the outbreak is likely to gain momentum. However, anthrax will not survive the change in body pH, if it is contained within a dead animal.
If you don’t know what has killed the animal, leave it strictly alone. Certainly to eat such a carcass, especially when there is an anthrax outbreak in the region, is sheer lunacy. People who eat anthrax infected meat will get anthrax which may take from one day to two months to become symptomatic and, if untreated, will lead to death.
Burn or deep bury infected carcasses, after covering them with quick lime. Dr Danie Odendaal of Afrivet says incinerating carcasses is best, because safe and effective burial needs a really deep hole.
Treatment and vaccination
The good news is that there is an effective vaccine that protects against anthrax. If the state has not vaccinated your herd, do it yourself.
Vaccinate young animals between four and six months and then boost the vaccine every year. If there are regular regional outbreaks, boost about a month before the expected time.
Vaccination for cattle is subcutaneous (under the skin) and in front of the shoulder. Vaccinate sheep and goats in the mid-thorax area on the side, halfway between the front and back legs, and horses in the middle of the neck. Keep horses out of work after vaccination for anthrax.
The anthrax vaccine is live so it is sensitive to antibiotics and to antiseptic agents.
Make sure animals are not on antibiotic treatment when you vaccinate against anthrax, and don’t wipe down the needles or the injection site with an antiseptic such as methylated spirits. Sterilise needles in boiling water.
Keep the anthrax vaccine in a cooler box to maintain the cold chain. If there is no fridge, use ice to keep vaccines cool. Heat will make it ineffective.
Let’s assume there is an outbreak close to your farm or grazing area, quarantine your animals as a precaution, and move them away from camps near the outbreak.
On the positive side, anthrax is treatable with penicillin. The problem is that one generally doesn’t know an animal has anthrax until it’s too late for treatment.
My personal strategy (I remind readers that I am not a vet) would be to block my herd or flock immediately, with a long-acting penicillin. This way, I would hope to catch any lurking, incubating anthrax. Depending on the life of the antibiotic, but somewhere between eight and ten days later, I would vaccinate the herd.
Find the funds and talk to your vet
Do not count the cost in implementing this kind of plan – borrow the money from your bank or your rich uncle if you have to. Use a few animals as security; but get the necessary treatment and vaccines.
Sitting back and hoping for the best just won’t cut it. You could lose everything you have worked for.
Always talk to your vet first. A good relationship with the vet is one of the best tools a livestock manager can have.
There is just no substitute for it. If you can’t afford a vet visit once a month, then try for one once every two months or even every six months. The vet will often help his clients with telephonic advice for which he usually doesn’t charge. I’ve never met a large animal vet who refuses to help with advice; even more so when there is a serious infectious disease around.