IMPACT OF LIVESTOCK DISEASES ON FOOD SAFETY

Safer food saves lives. With every bite we eat, we are potentially exposed to illness from either microbiological or chemical contamination. Unsafe food containing harmful bacteria, viruses, parasites, or chemical substances can cause more than 200 different diseases – ranging from diarrhea to cancers. Access to sufficient amounts of safe and nutritious food is key to sustaining life and promoting good health. 

Food safety, nutrition, and food security are closely linked. Unsafe food creates a vicious cycle of disease and malnutrition, particularly affecting infants, young children, elderly, and the sick. In addition to contributing to food and nutrition security, a safe food supply also supports national economies, trade, and tourism, stimulating sustainable development. The globalization of food trade, a growing world population, climate change and rapidly changing food systems have an impact on the safety of food. 

Public concerns over food safety are heightened during outbreaks of any disease in food-producing animals. If an animal is affected by a particular disease, tissues from the animal, including its meat or milk, are a potential source of human infection if allowed to enter the food chain.  More commonly, however, animals can be infected with zoonotic pathogens but show little or no signs of clinical disease. These ‘carrier’ animals are more difficult to detect either on the farm or at the slaughterhouse, so eradication is more of a problem. Many of these organisms live in the intestinal tract of healthy animals and can spread to humans through faecal contamination of the environment or of products such as milk during milking or eggs during laying. In addition, small amounts of intestinal contents may contaminate the carcass after slaughter and be present on raw meat.

Cross-contamination of other foods can occur if they come into contact with a contaminated product either directly, during storage or preparation, or indirectly via humans, work surfaces, utensils or other objects. Fruit or vegetables that have been irrigated or washed in untreated water that is contaminated with animal faeces can also be a source of human infection.

 Some of these diseases, however, like Peste des Petits Ruminants (PPR) and Newcastle Disease Virus (NDV) which are more prevalent in Nigeria have few or no implications for the human food chain. PPR poses no public health risk as humans are not affected by the virus. Though Newcastle disease is a minor zoonosis (disease of animals that can also infect humans) and can cause conjunctivitis in humans, however the condition is generally very mild and self-limiting. Other livestock diseases may carry a potential risk of foodborne transmission, but their impact on human health can be minimized through a combination of animal health control measures and food hygiene practices.