Like many parents in Totnes, Lotus Tarn would never permit her daughter to be vaccinated. “It’s just not natural to pump that sort of stuff into children when they are developing,” she said. “I would never allow that to happen.”

Tarn pointed to her 10-year-old child as she danced around the square outside the Greenlife wholefoods and remedies store in the south Devon town. “Look at her. She is so full of life. When we go to the natural doctor he says he can tell she hasn’t been vaccinated. Her immune system hasn’t been compromised. This isn’t hippy stuff, it’s the truth. The body can find its own solutions, its own intelligence, if we let it do that.”

Vince and Daisy (not their real names), who run a successful eco-business in Totnes, said they didn’t mind if people thought of them as “wackos” for not vaccinating their two young children. “The media portray it as a hippy movement but it’s not, it’s an educated choice for many people here,” said Daisy. “We spent months reading medical articles, speaking to parents of vaccine-injured children. Our human body can defend itself. We’re weakening ourselves if we vaccinate.”

Vince added: “Our children have never been sick. Rather than having some foreign bodies put into them, potentially causing disruption to them, they have been immunised naturally. Many people are simply taking the word of doctors and the pharmaceutical industry. If you do a bit of digging, scratch beneath the surface, you find a lot of corruption in the vaccine industry. Just follow the money.”

Health experts have expressed alarm at NHS figures showing a fall in take-up of routine childhood vaccinations across England. The figures showed a loss of confidence not just in the MMR (measles, mumps and rubella) vaccine but in basic immunisations given to babies in the first year of life.

Matt Hancock, the health secretary, has said the government is looking seriously at making vaccinations compulsory for state school pupils and has taken advice on how such a law could work. Other experts have come up with suggestions such as offering vaccines in supermarkets or at pop-up clinics or music festivals. The Daily Mail has launched a campaign encouraging parents to inoculate and criticising the “myths and online scare stories” around the subject.

If the figures nationally are concerning for the government, the statistics for Totnes, a haven for people seeking an alternative lifestyle, are even more stark. Across England, take-up of one dose of the MMR vaccine by five years old is 94.5%, slightly below the 95% target. The latest figure for the Totnes surgery, Leatside, is 78%.

Across England the coverage of the DTaP-IPV/Hib vaccine, which protects against infections such as diphtheria and whooping cough, at 12 months is 92%, the lowest since 2008-9. The south-west of England had 94% coverage for the same period, and the latest figure for Leatside was 84%.

Dr Julie Yates, Public Health England’s lead consultant for screening and immunisation in the south-west, said the vast majority of people did have their children vaccinated. “But there are a significant number of people who have alternative lifestyles and alternative views to healthcare. That’s reasonable. We respect that,” she said. “We offer what we’ve got and keep the door open. We tell them it’s never too late and if you change your mind you can come back. Keeping pestering them with invites and reminders doesn’t help.”

Yates spelled out what she saw as the dangers of not vaccinating in a letter published before a meeting organised by people who are against vaccinations, saying that while four or five children not being immunised per quarter might seem small, it could gradually build to a population of 200 unimmunised children over 10 years.

Yates said that over time this created a group of children and young people who risked becoming ill but could also pass on infections to other vulnerable individuals such as babies, or those with immune deficiencies who are not able to have the immunisations themselves.

She said there had been large outbreaks in the south-west in recent years, which she put down to a drop in the take-up of immunisations. “In 2015-16 more than 240 people developed measles in the south-west, with the outbreak starting and being centred in south Devon. We experienced a similar large outbreak last year, this time centred on Bristol, which is an area that has similar low uptake of immunisations,” Yates said.

“Nothing we do in life is without risk, but immunisation is the safest and most effective option, which is why more than nine out of 10 parents make this choice for their children. One hundred years ago, families sadly took it for granted that some of their children would die in childhood. Fortunately, the tragedy of losing a child is a now very rare occurrence. That difference has a great deal to do with developments in healthcare, including our world-class immunisation programmes.”

PHE works hard to make sure doctors and nurses in Totnes have the information they need to help them make their decisions and makes clinic times as flexible as possible to try to boost numbers.

Lucy Harries, a screening and immunisation manager in the south-west, said the figures for Totnes were concerning. “Vaccines work, vaccines save lives. We want to achieve the 95% uptake.”

But even some local doctors are not sure making it a legal requirement to have children vaccinated is a good idea. Dylan Watkins, a GP at the Leatside surgery, said: “I think the aim of increased or universal vaccine uptake is laudable and desirable but aiming to achieve it through making it compulsory is doomed to failure. It has not achieved its aim in other countries and if it were tried here people would subvert the process in any way achievable. In fact, making it compulsory would feed the conspiracy theorists and could, perversely, feasibly, reduce uptake.”

Confidence in the MMR jab appears to have been falling, at least partly in response to misinformation and scare stories spread on social media. The discredited claims of Andrew Wakefield, who in 1998 theorised that the jab was linked to autism, are widely circulated.

Many of the Totnes parents who are concerned about vaccinations reel off the ingredients they contain, such as aluminium, pork gelatine, egg protein and formaldehyde. Some believe that the ingredients could be toxic and that they are not compatible with choices such as veganism.

On its website explaining why vaccinations are important, the NHS says vaccines sometimes contain other ingredients that make them safe and more effective. It says: “There is no evidence that any of these ingredients cause harm when used in such small amounts.”