One of the Philippines' oldest and most exclusive golf clubs went into lockdown yesterday after a guest tested positive for the coronavirus shortly after returning to Singapore.

The Wack Wack Golf and Country Club is closing its golf course and clubhouse "to disinfect and sanitise the premises, to ensure that our club remains safe for everyone", club president Lawrence Tan said in a letter.

Media reports said a Singapore permanent resident went to the golf club as a guest of one of the members on March 2. The guest played a round of golf. He did not use the club's locker room, but his host did.

Grab Philippines president Brian Cu later issued a statement confirming he was the guest's host at the golf club.

The guest went back to Singapore on March 3. On March 7, he tested positive for Covid-19.

Mr Cu said he sent samples to the Research Institute for Tropical Medicine soon after learning his guest had tested positive.

A company representative said results came out negative.

Mr Cu disclosed that the other colleagues of his guest in Singapore all tested negative for the virus.

"I am not experiencing any ailments related to the disease such as cough, cold or fever," said Mr Cu.

Two caddies who were with the guest and his host have been asked to go on quarantine, the Inquirer said.

The Singapore permanent resident was reported to have stayed in the Philippines for three days.

A Japanese and a South Korean who had also been in the Philippines recently tested positive shortly after they returned home.

The Philippines currently has at least 49 confirmed cases of infection, with the spike in numbers happening in just the past five days.

There are close to 100 Filipinos who have also tested positive abroad, including three who are in Singapore.

A recent case involves a former top executive of Philippine conglomerate San Miguel, who is said to be "critically ill… and in induced coma" in a hospital in Paris.

He was on a trade mission in Paris and had also been in China and Russia. San Miguel said in a statement that the executive "is no longer with the company".

On Monday, President Rodrigo Duterte declared a health emergency amid growing anxiety that the deadly coronavirus is already spreading undetected in the capital Manila and in nearby suburbs.

The Health Ministry has raised its alert to "code red sub level 1", the second-highest level, after the Philippines recorded its first cases of local transmission.