For psychologists, however, face masks are de facto barometers, providing measures of people's reaction to the stress of the epidemic.

They said the number of Beijingers wearing face masks, especially outdoors, has dropped significantly compared with late April.

The trend is a sign that people are coming to terms with SARS and taking a more rational approach to the flu-like disease.

"We noticed that fewer people at bus stops and sidewalks are wearing masks," said Dr Zong Jie with Peking University's Psychology Department. "We believe they are getting the balance right."

Zong said panic over SARS overwhelmed people initially because they had insufficient information about the disease and their fears were fuelled by rumors.

The odds were high that they would copy what others were doing - wearing face masks indiscriminately - even if they were in well-ventilated areas, Zong said.

Sha Lianxiang, a professor with the Social Psychology Institute of Renmin University of China in Beijing, agreed.

Now that the public is better informed about how to prevent SARS, they are not unduly worried about it anymore, Sha said.

The latest national survey conducted by the Social Psychology Institute indicated that 57 percent of respondents said they wear face masks when they go out, a "very rational" percentage, Sha said.

But the fall in the number of people donning face masks could also be the result of "mental fatigue syndrome," said Zong, who also works on a SARS hotline in Beijing.

As the SARS epidemic in Beijing drags on for weeks and months, some people are increasingly trying to counter the adverse influence of the disease - and the fear it creates - on their everyday lives.

"They will vent their anger, while others will attempt to resume a normal life, which may in part explain why they choose not to wear face masks," Zong said.

Still, Zong warned that wearing a mask properly is a good way to help prevent respiratory tract infections.

People should wear masks when air circulation is bad or when they feel unwell.

Beijing resident Xiao Fu said he puts on his mask only when he gets on a bus or enters a store where air conditioners are inadequate.

Elsewhere? "I prefer to breathe unhindered," he said.

(China Daily May 12, 2003)