ANOTHER milestone in the Covid-19 vaccine roll out has been reached this week, with three quarters of the UK adult population receiving their first dose. Within the next few days, half of adults will have received their second dose. This is phenomenal progress, achieved within six months since vaccine delivery began.

But questions are being asked about children and Covid-19 vaccines. When will they receive them? Should they receive them? What do we know about the risks and benefits?

In Scotland, 16 and 17 year olds with underlying health conditions that put them at higher risk of serious disease are already eligible for Covid-19 vaccines following advice from the Joint Committee on Vaccination and Immunisation.

Young people in these age groups who are unpaid carers or frontline health and social care workers are also eligible. But thus far younger teenagers are not.

In contrast, a number of other countries are already pressing ahead with vaccinating 12 to 15 year olds. Algeria was the first country in the world to permit the use of vaccines for this age group from April with Canada following in early May.

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Since then, emergency use authorisation has been granted by regulators in the US and, as of May 30, over 2.8 million 12-15 year olds had received at least one dose of a Covid-19 vaccine there. Last Friday approval was granted by the European Medicines Agency and since then governments in both Germany and France have indicated that young people will begin receiving first doses from later this month.

So far, this roll out to teenagers is for one vaccine only, from Pfizer-BioNTech. They conducted a trial with teenagers and provided their results to regulators who carefully reviewed the findings before granting approval. These results were published last week in the New England Journal of Medicine.

The trial was designed to look at safety and how well the vaccine worked to protect against Covid-19 disease. It recruited 2260 12-15 year olds in the US, half of whom received the vaccine and the other half a placebo. Some children experienced mild side effects (sore arm, headache, feeling tired) but there were no vaccine-related serious side effects.

The Herald:

None of the children who received the vaccine developed Covid-19 more than seven days after the 2nd dose compared to 16 in the control group. As with the Covid-19 vaccine trials for adults, children will continue to be followed up to look at longer term safety and how long protection lasts for.

Results are expected soon from a similar trial being run by Moderna. Both Pfizer and Moderna have also recently started studies with children under the age of 12. A trial involving children is also underway with the Oxford Astra Zeneca vaccine in the UK but was paused briefly in April while medicines regulators reviewed data on blood clots in adults. So there will be more results in future that will determine whether vaccines are appropriate for use in those under the age of 16, including primary school aged children.

You would think providing Covid-19 vaccines to children would be acceptable given that vaccinating children for other diseases is common. We do it for meningitis, measles, mumps, whooping cough, and polio, for example.

Scotland and the rest of the UK have high rates of vaccine uptake among children. But there is still controversy about these particular Covid-19 vaccines. Perhaps because they are new, and parents want extra reassurance. But there are other reasons.

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The single biggest risk factor for Covid-19 disease and death is age – in fact the risks increase exponentially in older vs younger groups. Among the just over 10,000 Scots whose deaths have been registered since start of the pandemic and where Covid-19 is mentioned on the death certificate, just three of these have been in children under the age of 18. Comparable data is available for other countries – in the US there have been 437 deaths in children among the 474,710 people who have lost their lives up to June 1. Just 1-3% of children who get Covid-19 end up in hospital as most children have asymptomatic or mild disease. But the risks are not zero.

Long Covid has been reported in children even following a mild illness and there is a very rare but serious condition – Multisystem Inflammatory Syndrome or MIS-C – that children can develop following an infection. Vaccines would, it is expected, prevent this morbidity and mortality even if small numbers are infected.

Vaccinating children will contribute to population immunity, as we know children can be infected with Covid-19 and pass it onto others. There is good evidence now that vaccines help prevent transmission between adults, and the same mechanism would work in terms of vaccinated children being less likely to pass it on. This may be particularly important as we look ahead to the future when there are questions about the duration of protection provided to older people from existing vaccines. These are the main reasons that countries currently vaccinating children are doing so.

The final and perhaps most important area of controversy is vaccine equity. This is a point many others have made but it’s worth repeating. While two billion doses of vaccine have been delivered globally as of this week, the distribution is unequal. The proportion of people who have had one dose in North America and Europe as a whole is around a third compared to under one in five in South America, 6% in Asia and under 2% in Africa.

While rich countries vaccinate children the most vulnerable in poorer countries still go without. As regulators in the UK decide if and when we will start vaccinating children, this is a point that must not be forgotten.

Our columns are a platform for writers to express their opinions. They do not necessarily represent the views of The Herald.