Another two cases of H7N9 bird flu have been reported in Shanghai following this winter’s first case early this month.

A 58-year-old woman surnamed Zhang was confirmed with the infection last Friday and a 56-year-old man surnamed Shi was diagnosed on Saturday, the Shanghai Health and Family Planning Commission said yesterday.

The commission didn’t say whether they had contact with live poultry.

Shanghai’s first case, reported on January 4, was an 86-year-old man surnamed Zhou who had bought live poultry.

Officials from the Shanghai Center for Disease Control and Prevention said there was no evidence the H7N9 virus spread between humans and thus there was no need for panic. Effective protection from the virus, it said, was to reduce contact with poultry, especially dead or sick poultry.

Experts said exposure to live poultry at markets was a major risk factor and the city had taken preventative measures. Shanghai’s live poultry markets will shut from the end of this month until April 30 and the shutdown could become an annual feature for the next five years, authorities said.

The H7N9 virus emerged last year in China and has since infected around 150 people on the mainland and in Taiwan and Hong Kong, killing at least 45.

International experts say there is no evidence of any easy or sustained person-to person transmission of the strain. But an early scientific analysis of probable transmission of the new flu from person to person, published last August, gave the strongest proof yet that it can, at times, jump between people and so could cause a human pandemic.

The World Health Organization said the source of the human infections was still being investigated.

At the launch of a health education week in Shanghai yesterday, experts found many people didn’t know the difference between an ordinary cold and the flu.

A survey involving 6,327 residents found that more than 40 percent thought a cold and the flu were the same thing and could be cured without medicine while 12.4 percent believed antibiotics were a must for any kind of cold and that they could kill both bacteria and viruses.

Only 34.8 percent knew how the H7N9 virus spread and just 49.8 percent knew how to prevent the virus with measures such as good personal hygiene and avoiding contact with live poultry or wild birds.

The authority said it was disturbed at how some people would deal with birds or poultry which had died from disease.

The survey found that 3.5 percent would pick up the birds and throw them in a river while an alarming 1.1 percent said they would take them home to eat.