Health Minister Simon Harris has accused anti-vaccine campaigners of dangerous "scaremongering",
.He said their comments risk the health and in some cases lives of children and adults in need of vital medication care.
Speaking at an Irish Pharmaceutical Healthcare Association information event at the RCPI to mark world immunisation day, Mr Harris insisted that the only people who should be giving medical advice are doctors and qualified experts.
He said there has been a growing trend in Ireland and abroad of unqualified groups giving out "misinformation" about the realities of vaccines, resulting in cases were there remains a low take-up of the HPV cancer vaccine and treatments for other conditions.
Insisting the situation "is not harmless", he said the "nonsense" being put forward by some people "with no medical qualification whatsoever" is putting vulnerable people at risk and must not be listened to by the public.
"I'm not in any way qualified to give advice on vaccinations, but the people who are qualified are doctors, scientists, the European Medicines Agency, our medical community here in Ireland and the World Health Organisation.
"Sadly what we have seen in recent times are people who are not doctors, not scientists, not medical experts giving advice that runs counter to all the medical information available.
"That's not harmless, that has a real impact.
"We have vaccines in this country that can save lives, we have a vaccine that can prevent our young people who can prevent young girls dying of cancer, and yet we have misinformation, scare-mongering and quite frankly nonsense being given out by people with no medical qualification whatsoever," he said.
The vaccine information event also heard from Trinity college biochemistry and immunology expert Prof Kingston Mills, who said "it is incumbent on all of us to assess the benefit versus risks [of vaccines]," adding this should be based on "sound medical advice" and not "misinformation".