Health officials in Canterbury say more than 800 preschool children have now been vaccinated against hepatitis A.
The final two clinics in a mass vaccination campaign in mid Canterbury are being held in Methven and Rakaia on Wednesday.
Public health authorities are aiming to vaccinate 80% of the 1500 children aged between one and five in Ashburton and surrounding towns, to end a hepatitis A outbreak.
They say the vaccination is needed to protect everyone against the highly infectious hepatitis A virus which has already hospitalised four adults and a child.
Medical officer of health Alistair Humphrey says he is pleased with the community response to the mass vaccination campaign.
Dr Humphrey says unvaccinated preschoolers can still get the injection free from their doctor.
He is also reminding everyone that good hand-washing remains important.
Dr Humphrey says it is not clear what the resource-intensive mass vaccination clinics have cost, on on top of the $60,000 cost of the vaccine, but it will be money well spent if it halts the spread of the virus.
Whether that has been achieved will not be known until late December.