Dr Lech Beltowski takes a swab from Tammie Wolff, who arrived at Auckland Airport on a Qantas flight from the US. Photo / Greg Bowker

Dr Lech Beltowski takes a swab from Tammie Wolff, who arrived at Auckland Airport on a Qantas flight from the US. Photo / Greg Bowker

Tamiflu is available without prescription from today until September, but it will cost flu sufferers at least $60.

A full course of the unsubsidised drug, which is available over the counter for people showing flu symptoms, is priced at between $60 and $80.

The Government said yesterday it would provide for people who presented flu symptoms but could not pay that price.

Pharmacy Guild spokeswoman Annabel Young said the price of Tamiflu was a reasonable retail mark-up which covered the costs of running a pharmacy.

The ministry faced criticism from pharmacists who said over-the-counter sales would bring people with flu symptoms out of isolation, but said it would not relax its rules on the distribution of the drug.

The World Health Organisation announced yesterday that a swine flu pandemic was imminent, but New Zealand health authorities remained in a "contain and mitigate" phase.

A ministry report showed last night that 16 people were being treated as having swine flu, three who were confirmed by WHO tests as carrying the bug and 13 probable cases.

The number of suspected cases crept up to 111 from 104, and more than 121 were in isolation.

Auckland had the most people isolated with 72 and the only probable cases of influenza A.

Waikato District Health Board was investigating three further possible cases of swine flu yesterday, meaning it is now awaiting test results on four cases. Clearances for the region's first two possible cases came yesterday.

Deputy Director of Public Health Fran McGrath said the continuing increase in suspected cases was "absolutely what you would expect with influenza". Most new cases were relatives of people who had returned from the United States in the past week.

Director-General of Health Stephen McKernan announced that a specialist centre was being planned in Auckland to assess suspected cases.

The community-based assessment centre is likely to be at Middlemore Hospital, which is closest to Auckland Airport where incoming passengers are being screened.

"A community-based centre was provided for in the [pandemic] plan. Middlemore is much closer to the airport and has available clinical space," said Mr McKernan.