Rates of a highly-infectious virus which causes vomiting and diarrhoea in infants and children have dropped drastically since a vaccine programme came in.

New figures confirm a dramatic decline in rotavirus infections in Waikato, and experts say there'll be a similar picture across the country.

The findings will be presented at a conference today, and immunisation specialist Dr Nikki Turner believes vaccine hesitancy has been a hot topic at the event, with some hoping to answer the question of "why at times, even when the science around vaccines, people have myths and concerns and safety aspects that don't match our knowledge of science."

Turner said the message isn't yet getting through about the importance of pregnant women getting flu and whooping cough vaccines.

"We've got really strong and compelling data that vaccinating pregnant women is fantastic protection for our very young infants who themselves are too young to be vaccinated."

Turner insists the vaccines are great, they just need to work on how to communicate that.