Italys government on Friday declared a new law making a series of childhood vaccinations a condition of school inscription in a move triggered by a spike in measles cases.
The move will "make compulsory certain vaccinations that until now were simply recommended," Prime Minister Paolo Gentiloni said after a cabinet meeting approved the legislative decree.
After that age, the point at which school attendance becomes compulsory in Italy, parents will be liable for fines if their children are not vaccinated.
The 12 conditions which children must have protection against are polio, diphtheria, tetanus, hepatitis B, haemophilus B (Hib), meningitis B and C, measles, rubella, mumps, whooping cough and chickenpox.
"We are sending a very strong message to the public," said Health Minister Beatrice Lorenzin.
The move came amid reticence on the part of the education ministry and objections from the opposition Five Star Movement, which says the reform amounts to a gift to pharmaceutical companies.
Lorenzin pushed for change after the number of measles cases tripled, largely because of children not being vaccinated.
Her ministry blamed the spike on spurious health scares which resulted in the number of two-year-olds vaccinated against the common disease falling from over 90 percent a few years ago to 85 percent in 2015.
The World Health Organization (WHO) recommends aiming for coverage of 95 percent to prevent dangerous outbreaks.
Although it usually only triggers relatively mild symptoms, measles can cause fatal complications. In Italy's last major epidemic, there were 18,000 registered cases and 15 deaths.
The vaccine issue in Italy has become embroiled with broader questions of misinformation and "fake news", which the centre-left administration accuses its populist rivals Five Star of peddling.
Lorenzin last month reprimanded public broadcaster Rai over a programme raising issues about possible side effects of the vaccine against the virus that causes cervical cancer.
And Italy was one of the countries where a discredited scare about the combined vaccine for measles, mumps and rubella (MMR) being linked to autism gained the most currency.