BEIJING, May 29 -- In South Korea, the tally of patients of Middle East Respiratory Syndrome, known as MERS, has risen to seven. On Thursday, health officials in China quarantined one suspected victim in Guangdong province, after he arrived on a business trip from South Korea on Tuesday.

"The tally of infected patients rose to seven, six among them caught the virus from the first confirmed case. There was no additional infection caused by secondary infected patients," said Yang Byung-Kook, director of The Korea Center for Disease Control and Prevention.

"We confirmed on May the 27th that a suspected patient of Middle East Respiratory Syndrome left for China on May the 26th. Under the international health regulations, we notified the World Health Organization for Western Pacific region and China's health ministry to take him in to be examined and treated."

The rise in cases of MERS has alarmed many in South Korea, with health authorities in the country being criticized for not moving quickly enough to quarantine suspected patients. The health ministry in South Korea says that all of the seven patients infected have been linked to a man who returned from the Middle East - where cases of MERS are more common.

Meanwhile, Chinese authorities have placed the businessman suspected of being infected with the illness in quarantine. 35 people who came into close contact with the man, have so far shown no symptoms of the virus. MERS has been detected in more than 20 countries.