A nasty gastro-intestinal bug sweeping the country, with a handful of reported cases in the Bay of Plenty, has health officials urging the public to be careful around raw vegetables.

Toi Te Ora Public Health Services confirms five cases of illness associated with the bacteria Yersinia pseudotuberculosis in the last fortnight, part of the 100 cases nationwide and another 41 suspected cases.

Bay of Plenty Medical Officer of Health Dr Phil Shoemack.

The main cluster of outbreaks has been in Christchurch, with about 70 reported cases, while there have been cases in Auckland and the Hawke's Bay.

Yersinia pseudotuberculosis causes stomach cramps and presents symptoms similar to appendicitis, with diarrhoea resulting on rare occasions.

Bay of Plenty Medical Officer of Health Dr Phil Shoemack says there have been five cases reported in the Bay, with one being in the coastal Bay.

Anyone with similar symptoms are advised to consult a GP or seek medical treatment.

'These outbreaks were promoted about two weeks ago,” says Phil, 'and the work to date suggests that it's related to the consumption of contaminated vegetables, in particular lettuce and carrots.”

It is understood the Ministry for Primary Industries and Ministry of Health are working together to determine the sources of the outbreak but overseas outbreaks have been linked to contaminated fresh fruit and vegetables, contaminated water and animal contact.

SunLive is awaiting response from MPI on the matter.

Phil says despite the lack of 100 per cent confirmation, it is a timely reminder to the public of the importance of personal hygiene, particularly in terms of food preparation.

'That means people should wash their hands before preparing any food and eating,” he adds.

'And when preparing fresh food that is going to be eaten fresh and uncooked, it's really important that it's thoroughly washed.”

People are being warned to wash fresh fruit and vegetables as a precaution to reduce the risk of infection.

'Particularly food that's been grown in the ground because of potential contamination from what we call feral animals as well as manure which is often used as fertiliser,” adds Phil.