BEIJING (AP) – China announced its fourth confirmed SARS case of the season Saturday, saying the patient had already left the hospital after “total recovery” – a disclosure that prompted a strongly worded statement from the World Health Organization urging an urgent investigation.

The 40-year-old doctor fell ill on Jan. 7 with a high fever, sore throat and fatigue, the official Xinhua News Agency said. It cited an unnamed spokesman from the Health Ministry.

The man – identified only by his family name, Liu – checked himself into a hospital Jan. 13, Xinhua said. Within five days, “his body temperature dropped to normal and his condition stabilized.” Liu “was already discharged from hospital several days ago upon total recovery,” Xinhua said.

The doctor, who works at a hospital in Guangzhou, the capital of the southern province Guangdong, denied having any contact with animals or SARS patients, the report said. Health officials have been monitoring 48 people who had contact with him, but none has showed any symptoms, it said.

Criticized for its sluggish, secretive response last year after the initial outbreak of severe acute respiratory syndrome, the Chinese government has vowed to be more open and has since mounted an aggressive campaign against the disease.

Daily reports on suspected or confirmed cases are issued by the Health Ministry, and Xinhua reported on the third patient’s release from the hospital minutes after it said it occurred.

According to Xinhua, Guangzhou experts diagnosed Liu as a suspected case on Jan. 24 and the health ministry was informed two days later. It was not immediately clear why no word about him was released until Saturday.

“The case raises a number of concerns about the manner in which the man’s infection was detected, treated and reported,” the World Health Organization’s Beijing office said in a statement e-mailed to reporters Saturday night.

“WHO was not informed about this case until January 30,” the agency said. “Early detection, swift isolation and prompt reporting of cases are vital in the control of any infectious disease.”

It said it was told about the case four days after the man was declared a suspected SARS patient and two weeks after he was isolated. WHO said it was “strongly recommending further investigation into the sources of infection of recent SARS cases in Guangdong.”

Telephones were not answered at the ministry, and an official at the Guangdong anti-SARS office in Guangzhou said he “wasn’t clear” about any details of the case. He refused to give his name.

Liu’s case was announced the same day that two new suspected outbreaks of bird flu were reported in Guangdong and central Hubei province. The potentially fatal disease, which has ravaged poultry in much of Asia, has killed at least 10 people. Millions of chickens in 10 countries have been slaughtered.

China’s first confirmed case of bird flu was announced Tuesday in a duck in the southern region of Guangxi. On Friday, the government announced confirmed cases in its central provinces of Hunan and Hubei and suspected cases in Shanghai, Guangdong and Anhui, an eastern province.

No human infections have been reported in China so far.

The first known case of SARS emerged in Guangdong in November 2002. A subsequent worldwide outbreak killed 774 people last year, including 349 in mainland China, and sickened more than 8,000 before subsiding last July.

This season’s three other patients in China – a businessman, a waitress and a television producer – have been released from the hospital in recent weeks. All were from Guangzhou.

Earlier, WHO said it was important for health authorities to trace how the patients became sick as soon as possible.

“Now we have four cases without a concrete source of infection,” said Roy Wadia, a WHO spokesman in Beijing. “It’s something we’re very concerned about.”

AP-ES-01-31-04 1241EST