Medical experts in Hong Kong are suggesting changes to coronavirus containment measures to prevent imported cases, as they cautioned that the city faces mounting risks from overseas amid a global outbreak.

The remarks came after Hong Kong saw at least nine new cases in the past week with links to overseas travel. These patients or their close contacts visited countries including India, Japan, the United Kingdom, France, Mexico and the United States during their incubation periods.

The latest new case in Hong Kong was a 44-year-old male driver of a 56-year-old patient of Indian origin, who visited multiple countries before returning to Hong Kong and developing suspicious symptoms, health authorities said at a news briefing on Monday.

This has brought the city's total to 115 cases, including three deaths and 59 people discharged from hospitals.

Yuen Kwok-yung, a leading Hong Kong microbiologist and one of the Hong Kong's government advisers on epidemic control, noted that the current challenge for Hong Kong is to prevent imported cases from foreign countries－not the Chinese mainland.

It's increasingly difficult to cut the global transmission chains, as the virus has been spreading across the world, Yuen said.

Even when Hong Kong enters the summer, countries in the Southern Hemisphere will enter winter at the same time and have another outbreak, with the possibility of it spreading elsewhere, he warned during a radio interview on Monday.

Yuen said he believes the outbreak will be brought under control only after vaccines or specialized drugs are available, or 70 percent of the population develops an antibody against the virus.

This could take years, he warned. During this time the disease might become endemic in Hong Kong, always present but under control, like the flu, he said.

He suggested that the government considers requesting arrivals from epidemic areas to provide a health certificate, or complete a 14-day quarantine before entering Hong Kong.

As of Monday, novel coronavirus infections had been reported in over 100 countries and regions around the world. The number of remaining patients overseas has surpassed those in China, and reached 25,000, while China has some 19,000 patients.

Keiji Fukuda, a former WHO official who is also a member of the Hong Kong government's expert team on the COVID-19 outbreak, told China Daily that he thinks Hong Kong has to adjust control strategies, both on border control and local prevention.

"Control strategies like social distancing, keeping yourself at home when you are sick or not going out, personal hygiene, these things will become more important," he stressed. "But we are also trying to develop vaccines."

Another member of the government's medical expert team, David Hui Shu-cheong, a professor of respiratory and infectious diseases, said the government should constantly review the situation of the epidemic overseas, especially in developing countries such as India, as six cases in Hong Kong are linked to that country.

Limited medical resources there can result in inaccurate statistics of actual infection numbers, Hui warned.

Kathy Zhang also contributed to this story.

Contact the writers at heshusi@chinadaily.com.cn