The vaccine protects against human papillomavirus — a group of very common viruses that infect about four out of five people at some time in their lives.
HPV spreads through skin-on-skin contact, and most people would not know they had an HPV infection.
They often go away on their own, but sometimes they hang around and can lead to a range of cancers later in life.
Cervical cancer is the most common cancer caused by HPV, but the virus can also cause head and neck cancer, and cancer in other parts of the body.
About a third of all HPV cancers can also affect men.
The HPV vaccination programme was introduced in 2008, and a recent University of Otago-led study aimed to determine its impact on the occurrence of high-grade cervical abnormalities and cancer.
"We need to encourage all our young people to have this vaccine.
"It is incredibly important and makes a real difference.
"Not only does it prevent cervical cancer, it has the additional benefit of preventing other HPV-related disease, including cancers of the mouth and throat," he said.
Researchers matched data from the National Cervical Screening Programme with the national vaccination register and the incidence of detected cervical abnormalities.
They found vaccination was associated with a marked reduction — more than two-thirds — in cervical cancer and that vaccinated people were about one-third less likely to have pre-cancer cervical changes that required treatment.
The study identified a greater benefit for those vaccinated at a young age, which Prof Sykes said highlighted how the vaccination programme should effectively deliver to those aged under 16.
It also indicated the importance of an HPV vaccination programme as an intervention which promoted equity, as access to it was also found to be equitable for Māori, Pacific and European people.
He said the results of the study were what the researchers had hoped to see.
"All the effort and cost of introducing the HPV vaccination programme has been worth it.
"However, our vaccination rates are low, and they fell during the Covid-19 pandemic, particularly among Māori.
"If the promise of cervical cancer elimination for all people in Aotearoa New Zealand is to be achieved, it is essential we equitably improve vaccination rates and meet the World Health Organisation recommendation of vaccination of 90% of all young people.
"We need to invest further to meet the goal of eradicating cervical cancer as a public health problem for all."
