The campaigners allege that the dangers of vaccination is being ignored by medicine and demand free choice in vaccinating children.

The protesters gathered in Prešeren Square in the centre of town to demand that authorities change the current protocols for obligatory vaccination.

Despite broad consensus in the medical community that organised vaccination has brought extensive benefits to people by virtually rooting out numerous dangerous infectious diseases, protests like today's are part of a small but increasingly vocal campaign against vaccination in Europe.

Today's meeting in Ljubljana was part of rallies organised by like-minded groups in Bulgaria, Croatia, Macedonia, Montenegro, Serbia and Slovenia.

The Slovenian Society for Freedom of Choice, which put on the rally in Ljubljana, argues that parent should have the right to choose whether to vaccinate their children on the basis of the right to bodily integrity.

The group's head, Primož Verbič, alleged today that medicine refuses to admit the dangers of vaccination for children and therefore allows virtually no exceptions to obligatory vaccination.

While Slovenian law allows for exception to obligatory vaccination in children who may experience harmful side-effects, Verbič said the position of health experts means that few are granted the exception.

Alleging that dangerous side effects "are not rare", Verbič argued that vaccinated people had nothing to fear from those not wanting to be vaccinated.

Medical experts have rejected the arguments of the campaigners as inaccurate, saying that near-full vaccination of the population is the only way to effectively root out numerous dangerous infectious diseases.

Moreover, doctors warn that allowing healthy children not to be vaccinated would actually unfairly endanger children who are medically unfit for vaccination.

The current rate of vaccination in Slovenia under the national immunisation protocol for common infection diseases such as measles, mumps, smallpox and polio stands at around 98%.

Recent isolated outbreaks of measles in Slovenia have been used by doctors as examples of what can happen when the share of vaccinated individuals starts to drop, since no vaccine is fully effective and a small share of the population cannot be vaccinated.

In a notable case in March in the Ljubljana UKC hospital, a pregnant nurse vaccinated for measles was infected by a child she was attending to who had not been vaccinated because of a medical condition.

While the Slovenian anti-vaccination group alleges that children are being forced into vaccination, parents in the country can actually ignore the obligatory vaccination protocol at the risk of being fined EUR 500 for each vaccine. The fine is equivalent to that for running a red light.