Fewer babies in Hampshire were vaccinated against whooping cough last year than a decade ago, new figures show.

The World Health Organisation says 95% of children should be vaccinated against preventable diseases such as whooping cough.

It comes as cases of the respiratory disease have exploded this year, with the UK Health and Security Authority confirming the number of reported cases in 2024 is more than three times as many as last year.

A leading health expert has warned more babies will die if vaccination rates across the country do not rise.

UKHSA figures show 96.1% of babies in Hampshire had received their six-in-one vaccine by their first birthday, which provides immunisation against a range of diseases including whooping cough.

This was down from 96.8% the year before, and 99.3% a decade earlier.

It means Hampshire was one of only 31 areas to reach the 95% vaccination target set by the UKHSA.

Professor Sir Andrew Pollard, consultant paediatrician and chairman of the Joint Committee on Vaccination and Immunisation, told BBC Radio 4’s Today programme under-vaccination is putting "the most vulnerable – those who are too young to have been vaccinated – at greatest risk".

He said the "only thing we can actually do" about rising cases is to ensure higher vaccination rates.

He warned: "The troubling thing is that if we continue to have high rates of spread and low rates of vaccination, there will be more babies severely affected and sadly there will be more deaths."

The UKHSA confirmed five babies in England died after being diagnosed with whooping cough in the three months to March.

Meanwhile, in the year to April 21, GPs nationally reported 9,575 suspected cases of whooping cough to the UKHSA.

This included 387 in Hampshire.

Not all these cases will be confirmed as whooping cough. The UKHSA, which does not release local data, said there were 2,793 confirmed cases in England in the three months to March.

That compares to just 858 cases for the whole of 2023, while in March alone, some 1,319 cases were reported, according to the provisional data.

Pregnant women can also receive a whooping cough vaccine, though just 59.3% in England did between October and December 2023.

This was down almost 16% on the same quarter in 2016-17.

Sir Andrew said: "Very importantly, for this very vulnerable group, those who are too young to be vaccinated, is the vaccination rates in pregnant women.

"Very worryingly, those have fallen from a peak of about 75% of women being vaccinated during pregnancy to under 60% today, and that’s what puts these very young infants at particular risk."

Professor Sir Stephen Powis, national medical director for the NHS in England, said: "With cases of whooping cough continuing to rise sharply across the country, and today’s figures sadly showing five infant deaths, it is vital that families come forward to get the protection they need.

"If you are pregnant and have not been vaccinated yet, or your child is not up-to-date with whooping cough or other routine vaccinations, please contact your GP as soon as possible, and if you or your child show symptoms ask for an urgent GP appointment or get help from NHS 111."