All of the 75 people who had close contact with the first MERS patient in China were released from quarantine in Guangdong province by Wednesday midnight, the provincial Health and Family Planning Commission said on Thursday.

The first 44 people, after showing no symptoms and testing negative for the Middle East respiratory syndrome virus, were released on Tuesday at midnight. The remainder left quarantine on Wednesday at midnight.

The virus has an incubation period of two weeks, so the potential victims needed to be kept under close medical observation for 14 days from the last day they had contact with a South Korean MERS patient.

He had flown from Seoul to Hong Kong on May 26 and traveled by bus to Hui-zhou, Guangdong, via Shen-zhen, on the same day.

He was confirmed on May 29 to be the first patient with MERS in China.

"The risk of having a second-generation MERS patient in Guangdong was cleared after those who had close contact with the first patient left quarantine," said Zhong Haojie, an emergency management expert from the provincial Center for Disease Control and Prevention.

"The risk of a widespread MERS outbreak brought by the South Korean patient to Guangdong is extremely low, although we still have the risk of newly imported MERS cases from the Middle East and South Korea."

It took only four hours for the South Korean man to be found and sent to a hospital after the health authority in Huizhou was notified.

Altogether 78 people had close contact with the man in Guangdong, and all had been located by June 4, a week after the case was confirmed.

Three of them were found to have returned to South Korea and Taiwan, but the local health authorities were notified of their arrival and put them under medical observation, according to Song Tie, deputy director of the Guangdong CDC.

The prompt reaction was attributed to the importance the government places on disease control centers and to the emergency system China has established after battles against SARS and Ebola, according to Xu Angao, head of the Health and Family Planning Bureau of Huizhou.

The South Korean MERS patient is hospitalized in Hui-zhou; 66 people were put into quarantine there. The patient was in stable condition and his temperature was normal, Xu told a news conference on Thursday.

Experts have been sent to the hospital from across the country to discuss the treatment plan, and the government of Huizhou has spent more than 8 million yuan ($1.3 million) to purchase medical equipment, Xu added.

To quickly track down the patient and those who had close contact with him, government departments at the central, provincial and city levels, worked in close cooperation, Xu said.

Although the outbreak of MERS in South Korea continues tocn