THEY were the last age group to be offered Covid vaccinations, and uptake has been notably sluggish.

Just 18 per cent of boys and girls aged five to 11 in Scotland have received a first dose of Covid vaccine since the rollout was extended to all primary school-aged children in early April, having previously been limited to higher risk youngsters only.

In Highland - which has also been lagging behind in the delivery of second boosters to over-75s - uptake is a particularly lowly 6%.

HeraldScotland: Uptake of first dose by age group (Public Health Scotland)Uptake of first dose by age group (Public Health Scotland)

So why is coverage so low - and does it actually matter?

Firstly, Scotland is not unusual: in England, just 7% of five to 11-year-olds have been vaccinated six weeks into the rollout, while US authorities described "initial high demand" from parents which then "slowed significantly". More than two months in, it had stalled at around 28%.

In Wales, official figures revealed that nearly one in eight doses earmarked for the 5-11 age group had to be binned in the first week of the rollout because there was insufficient demand and, once opened, Pfizer vials have to be used up within six hours.

The unanswered question whether this is rooted in genuine vaccine hesitancy or simply ambivalence after successive waves which have already exposed the vast majority of youngsters to the infection.

HeraldScotland: Uptake of a first dose in the US levelled off after two monthsUptake of a first dose in the US levelled off after two months

Even the UK's Joint Committee on Vaccination and Immunisation (JCVI), which finally recommended a "non-urgent offer" of two microdoses of the Pfizer vaccine in February this year, noted that "it is estimated that over 85% of all children aged 5 to 11 will have had prior SARS-CoV-2 infection by the end of January 2022 with roughly half of these infections due to the Omicron variant".

If so, this alone may have delayed inoculations for as many as 178,000 youngsters in Scotland since guidance recommends a gap of at least 12 weeks between a positive test and a subsequent vaccination.

Parents may also have wondered, what's the point?

The risk of serious complications in very young children is extremely low unless they have other health conditions, such as Down's Syndrome.

READ MORE: NHS Lothian apologises over error in children's vaccine invite letters

According to National Records of Scotland (NRS), Covid has been an underlying or contributory cause of death for only four children aged one to 14 in Scotland since March 2020.

The JCVI stresses that vaccination is expected to "prevent a small number of hospitalisations and intensive care admissions" in the 5-11 age group; in fact, its modelling suggests that, even in the event of a future wave caused by a variant with disease severity more like Delta, only 98 hospitalisations due to acute Covid would be prevented for every million five to 11-year-olds double-vaccinated.

Given that around 74,000 youngsters in Scotland have had one dose so far (and presumably will get a second) that might translate into around seven fewer children needing a hospital bed for Covid.

However, if the pandemic continues to be driven by a milder Omicron-like variant "in a population with high levels of natural immunity", the JCVI anticipates vaccination having an almost negligible impact as far as the NHS is concerned: preventing 17 Covid-related hospitalisations for every million children fully jabbed.

Given that Scotland has 419,000 five to 11-year-olds in total, that would still only equate to seven hospital admissions avoided even if every one of them came forward.

HeraldScotland: The JCVI sets out the estimated impact of Covid vaccination on 5-11s based on prevention of hospital and ICU admissions depending in future Covid wavesThe JCVI sets out the estimated impact of Covid vaccination on 5-11s based on prevention of hospital and ICU admissions depending in future Covid waves

Overall, however, the JCVI stressed that the potential health benefits still outweigh the risks from any possible vaccine side effects.

But the fact that UK authorities took so much longer than their counterparts in Europe and North America to recommend the vaccine for children may have fostered undue suspicion in some parents.

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Misinformation has spread on social media in recent months, including fake parental consent forms falsely claiming that the chance of dying as a result of Covid vaccination is less than one in 30,000 (the true figure is more like one in five million for all age groups combined, and compares to a mortality rate from Covid infection of nearly one in a 1000 for unvaccinated individuals).

Worries have also been raised about the risk of myocarditis and pericarditis - forms of heart inflammation - after vaccination.

Analysis has shown an elevated risk of myocarditis in adolescents - especially teenage boys after a second dose - but this is still extremely rare, usually mild, and outweighed by the combined potential risk of cardiac and other complications associated with Covid infection.

HeraldScotland: The JCVI estimated that 85% of 5-11s in the UK would have been infected with Covid at some point by the end of January 2022The JCVI estimated that 85% of 5-11s in the UK would have been infected with Covid at some point by the end of January 2022

Among children aged five to 11 the risks appear even tinier: in the US, fewer than two cases of vaccine-related myocarditis were reported for every million doses administered.

In the UK, where the interval between doses is three times longer, this is likely to be lower still.

Meanwhile, scientists and campaigners critical of the delay to vaccinating younger children say it left them unfairly exposed to the virus and, in some cases, needlessly burdened with Long Covid.

READ MORE: Leaked report reveals delay in isolating Covid patient led to Lanarkshire hospital outbreaks

While vaccination doesn't necessarily prevent Covid infection (US surveillance suggests the low-dose paediatric Pfizer jags might be just 31% effective at stopping Omicron cases in children), it does appear to reduce the probability of it morphing into chronic, debilitating symptoms.

The Office for National Statistics estimates that more than 40,000 two to 11-year-olds in the UK have some form of Long Covid.

In an editorial in February, the journal Nature said it was "irresponsible of governments" to allow the virus to spread in children.

HeraldScotland: Data for England shows that Covid infection rates were higher among two to 11-year-olds in March than any other age group (Source: ONS)Data for England shows that Covid infection rates were higher among two to 11-year-olds in March than any other age group (Source: ONS)

That view is not universally shared, however.

Professor David Livermore, a medical microbiologist at the University of East Anglia, said the the UK "shouldn't be vaccinating children in the first place" given their low risk of serious Covid.

"These vaccines would be far better used in the old and vulnerable worldwide," he added.

Vaccinating children is always emotive; the MMR saga taught us that.

Whether UK children have been overly protected, or unfairly neglected, by the Covid vaccine rollout remains to be seen.