Image copyright BECTU Image caption Nurses say there will be more time to make sure all children are adequately vaccinated against diseases
The vaccination schedules for young children will now start in October rather than the middle of the month as initially planned.
The national plan for vaccinating children under the age of five covers 97% of children.
However, a cost-cutting deal between health trusts and the government has seen the recommended dates pushed back by four weeks.
There is concern that children may be excluded from nursery if they fail to catch up.
The reduction in the recommended dates has been blamed on the £400m pound funding shortfall suffered by Primary Care Trusts.
It also allows additional time for parents to arrange childcare, and make appointments and referrals for health and other appointments – these should not be affected by the change.
Mother and grandmother Jan Applegarth has a three-year-old granddaughter and a three-year-old grandson.
Mrs Applegarth said: “I find it incredible that there are still so many young children that are being missed out on being fully vaccinated, especially given the huge drop in the risk of infectious diseases in recent years.
“We were all taught to get the vaccinations as a matter of course during my childhood but without the data on the scale of the disease threat when I was young, I’m surprised that the government would expect young children not to be fully vaccinated now.”
A Department of Health and Social Care spokesperson said: “We will continue to introduce universal vaccinations for children in autumn this year.
“This means anyone who is yet to be fully vaccinated can see a GP or nurse and book in for the initial vaccination in person later this year.
“Parents and carers can continue to vaccinate their children in their local clinics or at home through routine vaccinations.”
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