Nine members of a Hong Kong family are feared to be infected with the coronavirus after sharing a hotpot meal, officials said Sunday.

Two members of the family -- a 24-year-old man and his grandmother, who is in her 90s -- are confirmed to have the virus, while seven more have returned preliminarily positive results for the disease, health authorities said.

Two more relatives are waiting for their results.

Officials said the family was part of a gathering of 19 who shared a hotpot meal over the Lunar New Year holiday at the end of January.

A hotpot -- also known as a steamboat -- is a bubbling cauldron of stock shared communally, to which diners add ingredients.

First found in the city of Wuhan in central China last December, the coronavirus has infected more than 36,000 people on the mainland and at least 29 in Hong Kong.

More than 800 people have died on the mainland, and one death has been reported in Hong Kong.

The semi-autonomous city began enforcing a 14-day quarantine period on Saturday for all people arriving from mainland China, in a fresh bid to curb the spread of the virus.

The city's health minister said Sunday that around 470 people have so far been ordered to stay at home, in hotel rooms or at a government quarantine camp since the policy took effect.