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1980s: a decade of diarrhoea

Food became a disease carrier on a massive scale in the 1980s. Two salmonella epidemics, the second larger than the first, hit the headlines. Less newsworthy but more common, Campylobacter gastroenteritis increased threefold to become the commonest diagnosed foodborne infection.

Botulism returned to produce as many cases in 1989 as had occurred since the twenties. Hepatitis A, although declining overall, became associated with food, particularly shellfish, whilst Giardiasis cases nearly doubled.

Better personal hygiene may have reduced early exposure to these diseases, so that individuals have not developed immunity, but this is unlikely to be the main reason for the rapid increase in foodborne infection. Changes in food production and preparation, and different patterns of consumption, are likely to be the most important causes.

Salmonella can be transmitted from cows or in poultry, and each source has contributed an epidemic to this decade. Infected chickens and eggs have caused the larger and most recent outbreak, with 25,000 cases reported (and many undiagnosed) and 57 deaths attributed to Salmonella in 1989 alone. It looks as if control measures in “battery” farming and public awareness of the risks have had an effect, for the epidemic’s growth appears to be slowing down this year.

Campylobacter probably comes mainly from infected poultry, and produced 33,000 reported cases in 1989. Fortunately it is a milder illness and not fatal, but this means that it is less likely to be diagnosed and reported to Public Health departments.

Botulism reappeared in an unlikely source: hazelnut yoghurt. This outbreak was relatively mild, given the severity of the illness, and was confined to 27 diagnosed cases, of whom one died. Rapid identification of the source made prevention of spread possible, but evidence from the US suggests that botulism may be due for a renaissance.

Hepatitis A has become significant as a form of food poisoning from shellfish contaminated by sewage. Giardiasis produced 6400 diagnosed cases in 1989, and although few were linked to food produced in the UK, reports from elsewhere link this lengthy and debilitating illness with both food and water sources.

This list is incomplete. Listeria caused much anxiety in 1989, although fewer people were known to be affected than with botulism. Beef has been associated with a frequently fatal disease caused by a bacterial toxin, but ‘mad cow disease’ has taken the limelight despite the absence of a single proven human victim. Yersinia and Cryptosporidiosis are out there too, so good advice for the nineties is to go easy on the take-ways and pass on the scampi until the producers clean up their act.