Salmonella serotypes isolated from minced meat beef, mutton and pork in Addis Ababa, Ethiopia

Foodborne salmonellosis often follows consumption of contaminated animal products, which usually results from infected animals used in food production or from contamination of the carcasses or edible organs [2, 3]. Salmonella infection in meat animals, including cattle, swine and sheep, arises from intensive rearing practices and the use of contaminated feeds [8]. Cross-contamination of carcasses with Salmonella can also occur during slaughtering operations. Stress associated with transport of animals to abattoir augments shedding of Salmonella by carrier animals and this may contribute to the spread of the organism to other animals in the slaughter plant [5, 13]. Slaughtering procedures potentially involve many risks of both direct and cross-contamination of carcasses and meat surfaces. During slaughter, faecal contamination of edible organs with subsequent contamination of the carcass may occur. This can be carried through all slaughter procedures up to the processing of the raw products, which are important sources of Salmonella in the human food chain [5, 10]. Contamination of equipment, utensils and hands of workers can spread Salmonella to uncontaminated carcasses and parts, which can occur in subsequent handling, processing, transport, storage, distribution and preparation for consumption. The true incidence of salmonellosis both in humans and animals is difficult to evaluate because of lack of an epidemiological surveillance system in place, which is particularly true in developing countries. However, the number of outbreaks particularly in humans has increased considerably in recent years [1, 7]. Carrier states of humans are of concern to the food manufacturing and food service industries because of the perceived risk of contamination of food by infected food handlers and the risk of foodborne disease outbreaks [9]. Meat processing and packaging at the wholesale or retail levels are likely to contribute to the higher levels of contamination in minced beef and pork products compared to beef and pork carcasses. The presence of even small numbers of Salmonella in carcass meat and edible offals may lead to heavy contamination of minced meat and sausage. When meat is cut into pieces, more microorganisms are added to the surfaces of exposed tissue. Raw meats, particuSalmonella serotypes isolated from minced meat beef, mutton and pork in Addis Ababa, Ethiopia