E.COLI
What is it?
Escherichia coli (E.coli) are members of a large group of bacteria M more than 700 types have been identified. They are mainly harmless and inhabit the intestinal tract of people and other warm blooded animals but a few strains, including the notorious O157:H7, can be deadly.
History
E.coli O157:H7 was first described as an ‘emerging food borne zoonotic pathogen’ (illness that can be transmitted from animals to humans) in 1982 during an investigation into an outbreak of haemorrhagic colitis (bloody diarrhoea), associated with the consumption of contaminated burgers.
Source
The US Centers for Disease Control and Prevention has estimated that 85 per cent of E.coli O157:H7 infections are foodborne in origin. E. coli O157:H7 is found in the guts of many animals, but mainly cows. The bacteria is excreted in the faeces and is a potential risk to anyone working with or visiting farmed animals and their environment. The increased number of human cases has been attributed to the intensification of farming practices and the consequent widespread use of antibiotics. Studies in France, Sweden and Canada have identified a positive correlation between the cattle density of an area and rates of human infection. Britain’s deadliest human E. coli O157:H7 outbreak occurred in 1996 when 21 people died after eating infected meat from a butcher in Lanarkshire, Scotland. Another 400 were infected. An inquiry found that there had been contamination between raw and cooked meat. Scotland has the highest incidence of E. coli O157:H7 in the world M every year about 250 people fall ill. Research by the Scottish Agricultural College suggests that E.coli O157:H7 is present in about eight per cent of cattle on about one in five farms. More recently, a major E.coli O157:H7 outbreak occurred in September 2009, when 36 cases were confirmed by the Health Protection Agency. The disease was spread by animals at a petting farm in Surrey. Twelve children under the age of 10 were hospitalised.
Symptoms in animals
E.coli O157:H7Linfected farmed animals show no signs of illness.
Symptoms in people
E.coli O157:H7 can cause a range of symptoms in people, from mild diarrhoea to severe abdominal pain. In a proportion of patients N2L7 per cent and mainly children, it can cause kidney failure. Infection with E. coli O157:H7 is now the leading cause of acute kidney failure in previously healthy children.
Routes of transmission
Consuming contaminated beef products is the most common source of infection for people, but the disease can spread by any food or drink that has been contaminated by animal (especially cattle manure). Contact with infected animals or their faeces are other routes of transmission.
Treatment
Most people recover without specific treatment. Use of antibiotics may increase the risk of complications. In serious cases, transfusions of blood or blood clotting factors as well as kidney dialysis may be necessary. Slaughterhouses are an obvious place for contamination of meat. Operators are urged to ensure the animals’ skins are not covered in faeces, and prevent the spillage of the digestive tract contents during and after evisceration (organ removal).