The Government has passed regulations giving medical officers of health greater powers to prevent the spread of swine flu.
The Government says the regulations, gazetted on Monday, are a precautionary measure as confirmed cases of swine flu continue to rise in this and many other countries.
The regulations give medical officers of health the legal power to require people to isolate themselves at home and to exclude children and teachers from school if they have swine flu or are in close contact with someone who has swine flu.
The Government has also recently added swine flu to the list of infectious and notifiable diseases.
Health Minister Tony Ryall says the regulations do not allow for total school closures, which can be done only with special authorisation from him or if an epidemic notice is in force.
Confirmed cases at 17
The number of confirmed cases of swine flu in New Zealand has risen by three to 17 in the past 24 hours.
There are also 10 probable cases and 92 people in isolation.
The Health Ministry says the seven-year-old son of a Canterbury man who returned to New Zealand from Los Angeles in late May has swine flu.
Another passenger on the same flight, NZ5, is the second new case to be confirmed.
Officials say they believe these two people caught the virus separately.
The third new case involves a passenger off Air New Zealand flight NZ124 which came in from Melbourne on 5 May.
Meanwhile, a south Auckland childcare centre closed after a case of swine flu may be able to open its doors again this week.
On Friday, a one-year-old from the Tama A Le Eleele A'oga Amata centre in Papatoetoe tested positive for the virus.
The 37 children and seven staff at the centre were given the anti-viral drug Tamiflu and quarantined.
Auckland Regional Public Health service says all results so far from those at the centre have come back negative - apart from the initial child.
If there are no further cases, the centre may be able to open as early as Thursday.