Addressing the media here, Lam said that she will personally chair an inter-departmental steering committee which will hope to issue strategic and other measures as soon as practicable, reports the South China Morning Post newspaper.
She also announced health declaration requirements would be extended to all entry points into Hong Kong, including the border crossings at Lo Wu and Lok Ma Chau.
Lam said the government would also look to impose temperature checks for outgoing travellers, with priority given to those heading to Shenzhen and Macau.
The Standard Chartered Hong Kong Marathon, scheduled for February 9, will be cancelled, with about 70,000 participants affected, Lam added.
Hong Kong school students would get two more weeks of holiday during the Lunar New Year and won't return to classes until February 17.
As of Friday, the five confirmed cases of the coronavirus infection in Hong Kong were patients who had travelled to Wuhan, the epicentre of the outbreak in China.
Flights from Wuhan to Hong Kong were cancelled since the Chinese city was put on a lockdown on Thursday morning.
The development comes after China's National Health Commission on Saturday put the death toll at 41 in the country, while the number of infected persons were 1,287, with 237 patients in serious conditions.
The WHO is yet to declare the outbreak as an international health emergency.
Besides Hong Kong, the others cases outside mainland China were reported in France (two), Australia (one), Thailand (four including two cured), Japan (two including one cured), South Korea (two), the US (two), Vietnam (two), Singapore (three), Nepal (one), Macao (two) and Taiwan (three).
( With inputs from IANS )