May 3, 2006
Stuff (New Zealand)
Nikki MacDonald
Public health experts are taking up their magnifying glasses, looking for clues to explain why New Zealand has the highest campylobacter rates in the world.
Notified cases of the nasty stomach bug increased again last year, after a brief drop in 2004, Environmental Science and Research’s 2005 notifiable diseases annual report shows.
Case numbers have risen by 75 per cent in the past five years, from about 8000 to almost 14,000 last year. New Zealand’s rates are the highest in the developed world, and Wellington rates are consistently some of the highest in the country.
Campylobacter bacteria are found in the gut of poultry, cattle, sheep, cats and dogs. Human cases of the bug are often blamed on poor preparation and cooking of chicken.
Of last year’s reported sufferers, more than half had eaten food from a restaurant or retailer, and almost 30 per cent had had contact with farm animals.
Food Safety Authority principal public health adviser Donald Campbell said it was not clear why New Zealand had such high campylobacter rates. However, work was under way to find out.
A telephone survey is being conducted around the country to find out if Kiwis are more likely to report, and seek treatment for, diarrhoea-like illnesses. The authority is also setting up a study to thoroughly investigate each reported case, in an effort to track its cause.
Food hygiene was variable, and a lot of work had gone in to remind people of the need for careful food preparation and storage, Dr Campbell said. However, there was nothing to suggest practices were worse in New Zealand than elsewhere.
Though often brushed off as “just a touch of diarrhoea”, diseases such as campylobacter and salmonella are a significant public health issue, because they can have serious and long-term consequences.
Last year 635 people were admitted to hospital with campylobacter, and one person died.
Wellington consistently has one of the highest campylobacter rates in the country, and last year was no exception. There were 1185 cases in the region in 2005, a rate of 482 per 100,000 residents.
Wellington infectious diseases specialist Tim Blackmore said it was a mystery why the region had such high rates. He had noticed a spike in cases over summer holidays, probably linked to barbecues.
Compared with salmonella and campylobacter, gastroenteritis cases fell last year, largely because of fewer outbreaks of norovirus in institutions such as rest homes and hospitals.