The mystery virus that has killed at least 78 people worldwide-- has now prompted both the World Health Organization and Japan to join a growing list of nations and groups to formally advise travelers to avoid Hong Kong and Guang Dong, China.

Researchers fear severe acute respiratory syndrome-- or SARS?has infected more than 2,200 people in 20 countries. Newsline?s Hayley Sterling has the latest:

Hoping to limit the spread of SARS--the Japanese government has issued an advisory to discourage travel to China. Japan?s top government spokesperson Yasuo Fukuda:

?First of all, we urge people to think if their trip to Hong Kong or to Guang Dong is necessary. We think it is advisable to postpone all unnecessary travel and we have announced this warning today.?

So far 14 people in Japan report suffering from SARS-like symptoms of fever, shortness of breath and dry cough?although none are confirmed. But fear is on the minds and faces of many travelers hoping to avoid contracting SARS.

Health investigators suspect the virus with no known cure?originated in Guang Dong province last fall?and quickly spread to Hong Kong, where travelers carried it into Toronto, Singapore, Vietnam and the U.S.

Chinese officials have agreed to cooperate with researchers. China agreed Thursday to allow the World Health Organization to travel to Guang Dong to investigate the illness more than four months-- after officials were first notified.

While scientists search feverishly for antibodies to fight SARS?groups like these Buddhist monks in Hong Kong seek cure through prayer. While others still turn to traditional herbal medicines.

Australia and Brazil are the latest countries to identify people who have contracted SARS.

Fear of contagion has spread to New Zealand?where a Chinese delegation scheduled to attend a conference was turned away. Businesses and organizers feared the Chinese may be carriers of the virus.

World health organization officials say only the coordinated efforts and timely sharing of data will contain the virus.