A vendor waits for customers near chicken cages at a market in Fuyang city, in central China's Anhui province, Sunday, March 31, 2013. (AP/AP)

Chinese authorities tried to calm spreading health concerns Wednesday after a third person was reported to have died from a new type of bird flu.

The emergence in China of the H7N9 strain of avian flu — a total of nine cases have been reported since it was revealed last weekend — are troubling because the strain has not previously been found in humans.

Even as two new cases were announced Wednesday, China’s state media sought to reassure the public that the chances of contracting H7N9 remain low. They also said that testing kits developed for the strain have been distributed to the national flu-monitoring network. Nothing so far, authorities stressed, suggests that the strain can be transmitted from one human to another.

The World Health Organization also urged calm this week but noted the importance of determining how the virus came to infect humans and whether it might spread. Just one patient so far appeared to have had direct contact with poultry. Dozens of people who came into contact with each patient are being monitored, authorities said.

A different strain of bird flu, H5N1, that emerged in 2003 has killed more than 370 people, according to the WHO.

Local media on Wednesday described the latest fatality as a 38-year-old chef in the eastern province of Zhejiang. A second patient from the same area was described as a 67-year-old retiree who was being treated in a hospital. Authorities revealed over the weekend that two other men had died in Shanghai.

Shanghai officials appeared particularly eager to dispel rumors that the new avian flu strain was related to the recent scandal triggered by the discovery of more than 15,000 dead pigs in Shanghai-area rivers. Public statements released Wednesday were aimed at assuring citizens that poultry and pork supplies in the city remain safe to eat.

The Shanghai Animal Disease Prevention and Control Center tested 34 samples from pig carcases and reported finding no traces of bird flu, state media reported. Many city residents, however, remain skeptical.

This week, Vietnam enacted a ban on all poultry products from China, stepping up border controls, while Taiwan put officials on alert and set up a monitoring group as a precaution against an epidemic-level outbreak.

Some experts have deemed China a higher risk for bird flu given the sheer size of its poultry industry and its use of production methods that put farmers in closer proximity to their chickens.

In their media and public-health response, Chinese authorities have been haunted by the specter of past medical crises, most notably the SARS outbreak of 2002 and 2003, when official censorship and tight control of information worsened matters. But Zhong Nanshan, director of the Chinese Medical Association, told Chinese media it is considered very unlikely that this bird flu strain will turn into a problem on the scale of SARS.