Vaccination does not just protect individuals but a high vaccination rate also prevents diseases from spreading, the National Institute of Public Health (NIJZ) said at a special news conference a day before the week was launched.

Slovenia has a relatively high vaccination rate for contagious diseases, with a falling vaccination rate stopping over the past few years, said Marta Grgič Vitek from the NIJZ.

"We've not had cases of polio, diphteria or rubella for several decades, while measles and mumps appear occasionally as single cases brought from abroad.

"It is important to keep the vaccination rate as high as possible to avoid outbreaks of the diseases which we have almost forgotten already," she stressed.

The head of the Health Ministry directorate for public health, Mojca Gobec, pointed out that in Slovenia vaccination is widely available to children.

"Preventing a disease is better than treating it. We'd like more people to understand that vaccination is a privilege and to trust experts."

She stressed that Slovenia was no isolated island and that travelling abroad posed a risk to spreading the diseases against which there was an effective protection.

But paediatrician Denis Baš said that pro-vaccination campaigns had resulted in more parents deciding to have their children vaccinated over the past few years.

What parents who oppose vaccination most often fear is side effects, so Baš would like paediatricians to have more time to respond to their concerns.

Slovenian medical students have launched the projects termed Vakcinet and Imuno to provide reliable information about vaccination by visiting schools, giving talks and promoting vaccination on social media.

Imuno project manager Vid Čeplak Mencin said their experience was that "there are not many opponents to vaccination, yet they are very loud and well organised".

The Vakcinet project also raises awareness about vaccination among medical professionals, who play a key role in preventing infectious diseases. Its head Ana Keršič noted their awareness was raising.

But many children still die world-wide as a result of not being vaccinated against diseases which can be prevented.

UNICEF Slovenija executive director Tomaž Bergoč said some 20 million children were still not vaccinated and 1.5 million died annually as a result.