Handling packaging containing raw chicken could cause food poisoning, Birmingham trading standard officers have warned.

The team said 40 per cent of all plastic packaging containing the meat in Birmingham contained food poisoning bacteria.

People are now being warned to wash their hands after handling chicken cartons and wrapping to combat the risk of catching the campylobacter bug which can induce vomiting, diarrhoea and abdominal pain.

In a pioneering survey of 20 supermarkets, convenience stores and butcher’s shops throughout the city, food safety officials found that eight were contaminated on the outside of the packet.

They also found seven chickens were contaminated inside the wrapping, while one tested positive for salmonella. There was no link between those infected inside and outside the packaging. Both types of bacteria are dealt with by thorough cooking and hand washing.

The council’s food safety team are believed to be the first to test packaging and they have now reported their findings to the Government’s Food Standards Agency and major retail chains. During the last three years there have been a steady rate of just over 900 reported cases of campylobacter poisoning a year in Birmingham.

Team manager Nick Lowe said: “Our message to consumers is that handling the packaging should be regarded as just as likely to cause food poisoning and touching the raw meat.”

He said that the contamination is believed to take place during the manufacturing and shipping. But fears that once handled in a supermarket the bacteria can be passed on through trolley handles, shopping bags and transferred to other foods.

In one supermarket a pool of juice collected on the chiller shelf was also contaminated.