The Hong Kong Jockey Club says it's closing the two clubhouses at its Happy Valley racetrack after four people who'd visited in the past two weeks tested positive for Covid-19.

The club says its old and new clubhouses will be closed from Tuesday until at least Thursday after the customers got in touch to say they had contracted the virus.

"The clubhouse management will review the pandemic situation and take appropriate actions as needed before re-opening the Happy Valley Clubhouse," the club said in a statement.

"The temporary closure will enable the clubhouse to complete the identification of customers and employees who have been in contact with the confirmed cases on the Happy Valley Clubhouse premises.

"The Clubhouse is arranging for the identified employees to undergo Covid-19 testing, and will continue to reach out to those customers who have come into contact with those confirmed cases in a timely manner."

The guests had spent time in the swimming pool, changing rooms and at various bars and restaurants on November 11, 15 and 19.

Hong Kong has seen an upsurge in Covid-19 cases in recent days, with some 132 cases linked to 21 dance studios across the territory.