Health officials on Monday reported 737 Covid infections, as they warned the tally could reach four digits down the line.

The Centre for Health Protection's Albert Au said the daily caseload has gone up considerably from around 300 two weeks ago, adding that authorities are keeping a close eye on the situation.

"The most important thing is we have to ensure there is no increase, or we need to monitor the trend of severe diseases, hospitalisation and the number of deaths. So far, we haven't noted a continuous increase in these parameters," he said.

Of the new cases, 305 were identified through laboratory testing, while 432 were from rapid tests that were later confirmed by the authorities. 104 of the new cases were imported.

Au also reported a small cluster of infections at a quarantine hotel, involving two cleaners and a room attendant at the Regala Skycity Hotel.

Three workers at the Central Kowloon Route construction site in Ho Man Tin also came down with the virus.

A cluster of infections had also emerged from the Fu Hong Society Yuet Kwan Home in Aberdeen, where five residents came back positive.

Au said 36 other residents from the home for the disabled would be be required to undergo quarantine at the AsiaWorld-Expo.

Meanwhile, several classes had to be suspended after 193 schools across the city reported a total of 275 infections.