The Italian health minister’s decision to sack the entire board of the country’s most important committee of technical-scientific experts, who advise the government on health policy, has raised alarm over who will replace them.

In a move on Monday night that shocked Italian scientists, Giulia Grillo, from the vaccine-sceptic Five Star Movement , which has supported unproven cures for cancer, said it was “time to give space to the new”.

“We are the #governmentofchange and, as I have already done with the appointments of the various organs and committees of the ministry, I have chosen to open the door to other deserving personalities,” she wrote on Facebook.

The decision will mean the replacement of 30 higher health council board members, including the president, Roberta Siliquini, the head of the school of hygiene and preventive medicine at the University of Turin who was nominated in December 2017 by the former health minister Beatrice Lorenzin.

Siliquini told the Guardian the move was concerning.

“We are worried about why they have decided to remove people who were selected due to their experience and competencies at the highest level,” she said. “We are also worried about who will make up the next council and especially if the nominations are politically motivated.”

Grillo did not explain in further detail the motive behind her decision. She said in her post that some of the removed board members “could be reappointed”, but “not the leaders … who must have the trust of and be in full harmony with the minister in charge”. She said on Tuesday that the new council would be formed in January and nominees would be selected “based on [their] curriculum”.

Alfonso Celotto, a former chief of staff at the health ministry, said the move was worrying but compatible with the populist government’s strategy to do away with choices made by the previous administration.

“They call themselves ‘the government of change’ and so want new people,” added Celotto. “But the crucially important thing is that the new people are competent – it would be like sending [Francesco] Totti away from the football team and replacing him with someone meagre. If you send Totti away you replace him with [Cristiano] Ronaldo.”

Celotto worked at Grillo’s ministry for just three months, but declined to say why he quit. News reports claimed it was because of differences over issues including vaccines.

Other distinguished experts on the board included the geneticists Giuseppe Novelli and Bruno Dallapiccola, and the pathologist Napoleone Ferrara. The members are nominated every three years and it is unusual for their mandates to be cut short.

Siliquini, who received a formal letter of her dismissal on Monday morning that contained no explanation, said that in the six months since Grillo became health minister the pair had never met.

“We’re the organisation that helps them, from a scientific and technical point of view, to make decisions on policy,” said Siliquini. “But she never asked us anything during these six months, which was probably a strong signal.”

In 2013 the Five Star Movement was a vociferous supporter of Stamina, a controversial stem-cell therapy promoted by a psychologist that was later proven to be a con.

Grillo has also caused confusion after making several U-turns on the government’s child vaccine policy. Her party, which is governing in coalition with the far-right League, came to power pledging to reform a policy brought in by the previous administration making 10 vaccines mandatory.

Grillo then said in June that parents could “self-certify” that their children had been vaccinated, instead of providing a doctor’s note, causing mayhem at the start of the school year. Then in mid-November, amid a measles epidemic, the government said it would uphold the vaccines obligation while calling for 800,000 infants, children and young adults to be vaccinated.