People don’t think of the far-reaching consequences of an action like bringing fruit illegally across the border, or of buying unmarked pigs at an auction. It might be out of innocence and ignorance that biosecurity measures are flouted, but the revenue lost can amount to billions of rand which can bring a whole sector to its knees – and threaten the livelihoods of thousands.
Biosecurity analyses and manages risks in the sectors of food safety, animal and plant life and health, including the associated environmental risk. It encompasses the policy and regulatory frameworks.
Investing in its capacity to control disease and to protect its food systems is in a country’s interest. Biosecurity is a national and regional issue.
For detailed and specific information about applying biosecurity principles to your operation, consult your veterinarian or the relevant commodity/trade association e.g. the Red Meat Producers Organisation (RPO) and National Emergent Red Meat Producer Organisation (NERPO), whose notes on precautionary measures to protect your herd against diseases acquired because of external contact can be found here.
While developing and maintaining biosecurity is difficult, it is the cheapest, most effective means of disease control available, and no disease prevention programme will work without it.
Infectious diseases can be spread between operations by:
Biosecurity has three major components: Isolation, Traffic Control, Sanitation.
Source: adapted from Biosecurity Basics for Cattle Operations and Good Management Practices (GMP) for Controlling Infectious Diseases, published by Institute of Agricultural and Natural Resources, University of Nebraska-Lincoln Extension
The word zoonosis has its origins in the Greek zoon, meaning animal, and nosos meaning disease. In 1959, the World Health Organisation Expert Committee on Zoonoses, defined zoonoses as “those diseases and infections that are naturally transmitted between vertebrate animals and man”.
Zoonotic diseases are an occupational hazard for all those who work with livestock, including farmers and their workers, veterinary staff, those in the abattoir and dairy industries and, ultimately, the consumers of animal products like meat, dairy products and eggs.
Preventing the transfer of zoonotic diseases from animals to humans rests on three pillars. The first of these is keeping animals healthy through good management, vaccinations and parasite control. The second pillar is personal hygiene and attention to healthy working conditions in the livestock industry – particularly details like the provision of good ventilation and accessible ablution blocks. The third pillar is food hygiene, maintaining a cold chain and the inspection and quality control of animal products from the farm to the table. If these three pillars are kept in place, the chance or risk of catching any disease from an animal is very low – you are much more likely to catch diseases from other people! Prevention is better than cure; however, if you suspect you have a zoonotic disease, it is advisable to consult a medical practitioner as soon as possible.
Further details on the symptoms and treatment of zoonotic diseases are obtainable on the World Health Organisation (www.who.int) and the Centers for Disease Control and Prevention (www.cdc.gov) websites.
The following table, used courtesy of Prof CME McCrindle (Faculty of Veterinary Science of the University of Pretoria), summarises the most important zoonotic diseases of livestock and gives some idea of how to prevent them being transmitted.
| Disease | How it is transmitted | Symptoms in humans | Prevention |
| Anthrax | Contact with blood, skins or meat of diseased cattle, sheep, goats and pigs | Skin, lung and intestinal forms; may be fatal if untreated. | Vaccinate cattle every year. Notify state vet if there are sudden deaths in livestock. Do not slaughter and eat sick animals. |
| Avian Influenza | Contact with diseased birds infected with the virulent strain | Influenza-like symptoms; often fatal in people | Do not handle dead birds of any species without gloves, face-masks and protective clothing. |
| Botulism | Consumption of meat or other foods contaminated with the spores or toxins of Clostridium botulinum | Flaccid paralysis of muscles; it progresses until the patient cannot sit or stand, and eventually is unable to breathe. | Vaccinate cattle. Food hygiene and cooking at high temperatures. |
| Bovine brucellosis | Inhalation of or contact with blood or birth fluids of infected cattle; drinking unpasteurised milk | Acute symptoms look like malaria or influenza; chronic intermittent fever, joint problems | Vaccination of heifers, regular testing of cattle herd. Hygienic handling of aborted material or afterbirths. Pasteurise milk. |
| Bovine tuberculosis and human tuberculosis | Inhalation of droplets from coughing cows; drinking unpasteurised milk | Nodules on the skin and in the lymphnodes; chronic weight loss, severe cough with bloody phlegm | Workers in dairies must be checked regularly for TB. Dairy cattle must be tested regularly for TB. Pasteurise milk. |
| BSE | Consumtion of brain, lymphnodes or spinal tissue of affected cattle | Chronic nervous symptoms that become worse; always fatal as it is incurable | Prevent the disease coming into South Africa. Test cattle that die after showing nervous symptoms. |
| Bacterial wound infections | Cuts and wounds that are exposed to animal manure, pus and would infections of animals | Abscesses, gangrene and “blood poisoning” | Wash and disinfect all wounds immediately using running water. Cover wounds if working with animals, meat or milk. |
| Bubonic plague | Bites by rat fleas | “Bubon” forms in inguinal lymphnode, fatal pneumonia | Rat control. Control fleas on animals – including goats, dogs and cats. |
| Colibaccilosis | Consumption of food, water or other material containing the organism Escherichia coli | Severe acute gastroenteritis; if caused by Ecoli serotype 0157, severe bloody gastro-enteritis and organ failure | Food hygiene. Clean drinking water (prevent it being polluted by human and animal excreta). Wash hands after handling animals and before eating. |
| Cryptosporidiosis | Consumption of food, water or other material containing the organism Cryptosporidium | Severe chronic diarrhoea, difficult to treat | Prevent water being contaminated with human or animal excreta. Wash hands after handling animals and before eating. |
| Congo Fever | Contact with the blood of infected animals or bites by the tick Hyalomma spp., or infected people | Muscle pains, fever, severe haemorrhage under the skin and internally; highly fatal. | Do not crush ticks with your fingernails. Use tick repellents when working in areas with high tick levels. |
| Pseudo Cowpox (Bovine Orf) | Contact with infective nodules on cow teats | Red inflamed nodule on the hands | Hygiene during milking. Prevent transmission between cows. |
| Neuro-cysticercosis | Consumption of the eggs of the pig tapeworm Taenia solium | Cysts on the brain can lead to epilepsy and madness in people. | Personal hygiene – wash your hands well and scrub your nails before eating. |
| Diamond skin disease (Erysipelas of pigs) | Contact with the skin, meat or blood of infected or carrier pigs | Large painful nodule on the hands. Can also cause vegetative endocarditis (growths on the heart valves). | Vaccinate pigs against Erisipelas. |
| Hydatid disease | Consumption or ingestion of the eggs of the tapeworm Echinococcus | Large cysts on the brain, lungs or in the liver of people | Do not feed raw meat, especially cysts from sheep carcasses, to dogs. |
| Leptospirosis | Contact with pigs or cattle infected with the disease; contact with infected water | Kidney failure, jaundice and liver failure; responds well to antibiotic treatment. | Control rats (they carry the disease). Test for the disease in livestock if there are abortions. |
| Orf | Contact with sheep or goats infected with orf | Contagious ecthyma, red swollen areas of skin of hands or face | Wash hands well and do not touch your face while working with sheep or goats. |
| Q-fever | Inhaling dust in the kraals, contact with aborted material from cattle, sheep and goats; drinking unpasteurised milk | Swollen lymphnodes and interstitial pneumonia | Wear masks if working in dusty kraals; protective clothing when working with aborted foetus and uterine fluids. Pasteurise milk. |
| Psittacosis | Inhalation of the droppings or blood of infected pigeons, parrots, ducks and turkeys | Severe coughing which can result in heart failure and death if untreated | Have sufficient ventilation when working in pigeon or poultry houses. Use a face mask and gloves if doing necropsies on dead birds. |
| Rabies | Bites by infected dogs, jackals, cattle, horses, sheep, wildlife | Mania and death | Vaccinate all dogs. If cattle or any other animals show symptoms, call the state veterinarian URGENTLY. If bitten, go straight to a clinic or doctor and inform the state vet. |
| Rift Valley Fever | Mosquito bites during an outbreak, contact with blood or aborted material from infected sheep or cattle | Fever, retinitis with haemorrhage and edema, causing blindness. Encephalistis, liver and kidney failure. Can be fatal. | Vaccinate sheep if there is an outbreak. Use protective clothing and masks if working with infected animals or carcasses. Control mosquitoes. |
| Ringworm | Contact with infected animals | Round, scaley skin lesions | Treat animals with ringworm. Consult a physician if you become infected. |
| Salmonellosis | Consumption of food, water or other material containing the organism Salmonella; contact with animals infected with Salmonella | Severe gastro-enteritis which can be fatal in the very young and the elderly. Sometimes septicaemia and organ failure. | Food hygiene. Prevent contamination of food with animal faeces. Remember personal hygiene and wear protective clothing if working with sick animals or their faeces. |
| Sarcoptic mange | Contact with infected pigs, dogs and cats | Small red itchy areas on the skin due to infection by the mite Sarcoptes scabei | Treat and control sarcoptic mange in animals. |
| Tick bite fever | Bites by ticks | Blackened area after 10 days where bitten by a tick; severe headaches. | Consult a physician for treatment with antibiotics. |
| Toxoplasmosis | Consumption of poorly cooked mutton or pork; ingestion of soil contaminated with cat faeces | Granulomas in the brain of HIV positive people; abnormalities in newborn children if mothers infected while they are pregnant | Cook meat well. Scrub hands and nails before eating, particularly after digging in gardens. |
Source: Prof CME McCrindle, Section head of Veterinary Public Health, Department of Paraclinical Sciences, at the Faculty of Veterinary Science of the University of Pretoria.
Biosecurity legislation includes:
… It is safe to argue that the single largest driver of growth of the South African agriculture and agro-processing sector is animal health and overall biosecurity.
Yet the animal health system, an essential precondition to achieve [growth], is currently inefficient in managing diseases, resulting in more frequent and widespread outbreaks, which hampers productivity and limits export opportunities. Failure to address disease management constraints through improvement in animal health services is costing the industry and the country billions of rands in lost exports and South Africa is missing out on what is perhaps one of the greatest opportunities for inclusive growth in agriculture.
Animal diseases will remain a great concern in the livestock industry and the situation is exacerbated by the shortage of veterinary health professionals in the country. The international norm is to have between 200 and 400 professionals for every million people; in South Africa there are between 60 and 70 veterinary professionals for every million people. This results in inadequate services being provided to small and communal producers, posing a great risk for the country’s biosecurity and growth prospects.
Find documents, forms, contact details for port, regional and national offices, and information on the different directorates on the website www.dalrrd.gov.za (take the “Branches” menu option).
Find the list of provincial contacts for state veterinarians on the “Animal health” page.
Further reference:
Training and research
Companies
Government
Some articles
Regional Plant Protection Organisations (RPPOs):
