Salmonella
Karin, a 7 year old girl from Germany, loves eating scrambled eggs on Sunday mornings with her grandmother, Astrid. Every weekend, they get up early before breakfast and walk to the market to buy fresh eggs from a local farmer, Oliver. Oliver has been selling eggs produced from his flock of chickens for over twenty years and is acutely conscious of ensuring that his products are safe and healthy. One of his main concerns is Salmonellosis, a potentially deadly foodborne disease that is predominantly contracted by humans through the consumption of infected food such as eggs, meat, vegetables and fruit.
Salmonella is the most common zoonotic infection often transferred by food. It was first identified in 1884 by Dr. Daniel E. Salmon, who isolated the bacteria from the intestines of a pig. Almost 80 per cent of human cases today stem from chicken meat and eggs (Salmonella enteritidis) and the gastrointestinal tract of animals (Salmonella typhimurium). Salmonella bacteria residing in untreated water is also known to cause typhoid fever.
In humans, the disease can cause nausea, vomiting, abdominal cramps and diarrhea; it can even result in death. In fact, Alexander the Great’s death in 323 BC is said to have been caused by the bacteria. Although in most cases symptoms are temporary and self-limiting, they can sometimes be more severe in young children like Karin and the elderly like Astrid, which is why it is vital for farmers such as Oliver to prevent their poultry and eggs from being infected with salmonella.
In a world without animal health products, Oliver would not be able to reduce the risks of disease in his food products. With the help of livestock veterinarians to ensure his animals are as healthy as possible, Oliver routinely checks his flocks for Salmonella and takes measures to reduce the prevalence in his chickens. Although no single measure alone can achieve effective Salmonella control, vaccination and prevention (also known as biosecurity) can help to reduce the risk of infection significantly. In some quality assurance programmes the use of Salmonella-vaccines is obligatory. As a matter of fact vaccination is obligatory across the EU under certain circumstances to reduce the prevalence.
Although measures to control infections in animals reduce the risk of Oliver selling contaminated food, it is still important for Astrid and Karin to take measures into their own hands to protect their health by good kitchen and hygiene practices. Once they return home from the market, they scramble the eggs at a high temperature (above 75°C) and wash their hands with soap and hot water after handling them. By taking these precautions, Astrid and Karin are able to enjoy their breakfast without the fear of salmonella infection.
Preventing salmonella infection is important at every stage of the food chain; from Oliver’s farm to the end consumer, in this case Astrid and Karin. (See CDC diagram on “prevention from the farm to the table – salmonella”)
