HONG KONG - The Hong Kong Special Administrative Region (HKSAR) government will closely monitor South Korea's Middle East Respiratory Syndrome (MERS) situation, as third tier infection may have occurred, Secretary for Food and Health of the HKSAR government Ko Wing-man said here on Wednesday.

Ko told reporters that despite all of South Korea's confirmed cases being infected within a healthcare setting, the HKSAR government will be on alert for other sources of transmission.

Hong Kong authorities boosted port health surveillance on Tuesday by requiring visitors to sign a health declaration confirming that the information they provide is the truth.

Hospital authorities also urged healthcare workers to suspend all medical exchange activities in South Korea, especially those in Seoul.

Ko said travelers to South Korea are advised to avoid healthcare institutions, adding they should wear face masks and keep their hands clean if they must visit such facilities.

Eighteen people in Hong Kong having close contact with a South Korean man infected with MERS have been sent to a quarantine camp, the HKSAR government said earlier.

The 44-year-old South Korean MERS patient flew from Seoul to Hong Kong last Tuesday before heading to the China's mainland by bus.