The Centre for Health Protection (CHP) on Friday called on members of the public to exercise caution when travelling to the Middle East.

The reminder came as the World Health Organisation reported four new cases of Middle East Respiratory Syndrome (MERS) in Saudi Arabia, involving chronically-ill men aged between 27 and 78.

Two of the patients have passed away.

In a statement, the CHP said one of the infected patients has had indirect contact with dromedary camels and their raw milk.

"The CHP also recommends travel agents organising tours to the Middle East to refrain from arranging for visitors to ride dromedary camels or to participate in any activities involving direct contact with dromedary camels, which are known risk factors for acquiring MERS-CoV," the statement read.

Officials also reminded people to maintain good personal hygiene.