Five children die unnecessarily every day of conditions such as asthma, meningitis and pneumonia because NHS care for young people is badly organised and dangerously inadequate, the leader of Britain's 11,000 specialists in children's health warns.

About 2,000 children a year lose their lives because of an array of problems, which means the UK has some of the worst death rates among children up to the age of 14 in Europe, the president of the Royal College of Paediatrics and Child Health told the Observer. Branding the situation "a major crisis", Hilary Cass said in an interview that sick children were at greater risk of dying because some GPs lacked paediatric skills, expertise was absent in too many small paediatric units, and there was a serious shortage of consultants. The college believes a lack of senior paediatric doctors is so acute that the safety of treatment cannot be guaranteed at every unit. Cass urges the NHS to instigate radical changes in how it treats children, including a centralisation of hospital services to reduce preventable deaths.

Cass, a consultant paediatrician at London's Evelina children's hospital, cited World Health Organisation (WHO) research showing that 6,198 preventable deaths a year among children up to 14 across 14 European countries, including the UK, could be avoided if they all tackled children's health as effectively as Sweden.

"In Britain there are five deaths of children a day – 2,000 a year – that are preventable and unnecessary if our services perform as well as those of Sweden. The country's children are our future. We should do so much better. This is a major crisis," she added.

The WHO's mortality database for last year shows that the UK had by far the highest number of the 6,198 "yearly excess child deaths compared with Sweden" across the 14 nations – 1,951 in all. That was more than twice the number in France (962) and more than that in other similarly sized countries such as Germany (815), Italy (683) and Spain (545).

"What do these 6,000 children a year die from?" added Cass. "Some are born with severe congenital abnormalities. They have palliative care and die within the first few weeks, well supported."

But the main other group, apart from those involving accidents, are what experts call "healthcare amenable" – that is, the child would not have died if treatment had been better. "If services were improved, we could do something about those five a day," said Cass.

The WHO found that the UK had the worst asthma mortality rate among 0- to 14-year-olds among eight European nations and was fourth worst out of 15 for pneumonia deaths.

Failings in care mean that only 3% of children with asthma have a personal care plan and only 4% of children with diabetes receive care that complies with existing guidance, while deaths from meningococcal disease are two to three times higher than in other western Europeancountries, Cass said [see footnote]. Failure to overhaul how services are organised and delivered means the UK has gone from having average childhood mortality to being the worst in Europe.

Her concerns are supported by the royal college's new medical workforce census, a major biannual study among the UK's 11,000 paediatricians to investigate the pressures on them. It identifies problems such as:

■ Sharply rising demand as more children contract non-communicable diseases such as asthma and obesity.

■ A chronic shortage of consultants, especially when hospital units are busiest.

■ Worryingly wide variations in the number of consultants in different parts of England, with 48 per 100,000 children aged 0-15 in London, but just 27 per 100,000 in the east of England.

Cass's prescription for improving children's health services – cutting the number of hospitals providing such care and offering more care in the community – is controversial given the opposition aroused when any rundown of a hospital's services is proposed, and is unlikely to be endorsed by ministers so close to the 2015 election.

Children's health minister Daniel Poulter said Cass was right. "Children's health is an issue that is right at the top of the healthcare agenda, and I agree that our NHS needs to do better on this," he said. "We have asked every organisation with the power to make a difference to pledge to work together to improve children's health by delivering more care in the community to better look after children with disabilities and long-term illnesses, like asthma and diabetes."We want our NHS to do even more to make sure every child has the same opportunity

to lead a healthy life, no matter where they live or who they are."

• This article was amended on 17 July 2013. The original referred to children with diabetes and went on to say that diabetes is closely related to obesity. To clarify: only a small percentage of children with diabetes have Type 2, which can indeed be related to obesity. The large majority (90%-95%) of diabetes in the age group 0 to 14 is Type 1, which is an auto-immune condition, not lifestyle-related at all.