A mother whose daughter will need testing for HIV and hepatitis after a trip to the dentist says she does not blame the clinic, and will continue to use it when it reopens.
Pukekohe Intermediate School's Dental Clinic was closed on 23 January after it was found that a hose used to suck out saliva and blood from children's mouths was connected to one that blows in air.
This means there may have been cross-contamination.
About 2500 children who were treated between 13 September and 23 January when the clinic was closed will be contacted within a week to set up a time for testing.
Helen Alexander's 10-year-old daughter Anna had a dental procedure last October.
Ms Alexander said she had looked at the details and information and although there was a low risk she was still worried.
"One of my first thoughts was what do I tell my child, because as an adult you can discern information and make a judgment that there's a low risk. But a 10-year-old child doesn't have that kind of maturity," Ms Alexander said.
"I'll probably tell her that she needs testing to see if she's picked up any bugs but if it turned out that she had something serious then we could deal with that then. But I don't want to worry her now."
She would wait and see if she got a call from the nurse today and contact them the following day if she had not, Ms Alexander said.
She did not blame staff and would continue to take her children to the clinic when it was up and running again.
Machine faults happened, so it was not done intentionally or neglectfully, she said.
"We just need to make sure we do the right things now."
District Health Board chief medical officer Gloria Johnson said infectious disease specialists had indicated the risk of cross-infection to children was low as it was extremely rare for New Zealand children to have blood-borne viral infections.
It was not easy to tell which children had been exposed until they were tested, she said.
"These children range in age from two-year-old through to 12-year-old and probably about a quarter of them are pre-schoolers.
"Many of the children will only have had a visual inspection of their teeth and won't actually have had anything done. But it's not easy for us to quickly determine which child actually had what done from our records."
Testing began today at two clinics.
"We have established that it's not going to make any difference to the health risks for the individual children exactly how quickly they are seen, and I do want to emphasise the risks really are very low indeed," Dr Johnson told Morning Report.
"We are aiming to see all of the children in about the next three weeks and are aiming to contact them all within the next seven days."
The DHB had sought "extensive expert advice" about the possible risks, she said.
"The risks of transmission in this circumstance are very much lower than initially it might sound as they would be.
"The lines are flushed with an antiseptic which in fact should remove any risk of infection. We are very much erring on the side of caution in doing this."
The September cut-off date was the last time the centre was absolutely sure the system was functioning normally but the DHB believed the issue was quite recent, with no visible problems in the system until January.
However, it did seem likely to be a human error, Dr Johnson said.
"It appears that that would have to be, that somebody has made an incorrect attachment. One of the things we are going to be asking the engineering firm that produces it to do is to see if there is something they can do to make it impossible to make that misconnection so nobody can do this again."
She also reassured that all other dental clinics in Auckland city which used similar equipment had been checked already.
"None of the rest of them have this problem. I don't know whether other dental clinics elsewhere in the country use the same equipment as us."
Dozens of parents and children turned up at Pukekohe Intermediate Dental Clinic this morning where children were being screened.
Mother of seven Danielle's two youngest boys received treatment during the affected dates so were given blood tests straight away.
She said the Ministry of Health's healthline had been very informative and reassuring. Parents she has spoken to understand the risk of contamination is extremely low.
Another parent, who did not want to be named says he was concerned about the possibility his daughter had caught hepatitis or HIV.
Dr Johnson said the two clinics open for testing would subsequently be open from 8am to 8pm, seven days a week.