Twenty people at Gisborne Boy's High School have been quarantined after suspicions they may have swine flu.
Five of the group of 17 students, two teachers and one parent showed mild flu-like symptoms after returning home from a school trip to Brisbane on Sunday.
The five have been prescribed the anti-viral drug Tamiflu, and public health staff have taken swabs from the others.
The results of the swab tests are expected to be available on Wednesday afternoon.
Tairawhiti Medical Officer of Health Geoff Cramp says 12 of the group are showing possible symptoms. But he believes the level of risk is low because of the small number of confirmed cases of the H1N1 virus in the state of Queensland.
On Tuesday, two Wellingtonians were confirmed with swine flu, lifting the country's confirmed total to 19. Others are in Auckland, Christchurch and Hawke's Bay.
The Ministry of Health says the two Wellington individuals arrived in New Zealand from Los Angeles on 31 May.
Staff at Wellington's Regional Public Health unit are tracing close
contacts of the pair, along with those of another Wellington person, a passenger on NZ124 from Melbourne last Friday, who has also been confirmed with swine flu.
The ministry has emphasized the need for good personal hygiene in countering the spread of the virus.
In Australia, authorities have confirmed more than 1,200 cases of swine flu, at least 1,000 of them in Victoria.
Globally, there are more than 25,000 cases in 73 countries.