The decision over whether to offer he Covid vaccine to children aged 12-15 will be made by the four Chief Medical officers of the UK after the government's independent vaccine advisors said the medical benefits were too marginal for them to recommend it's use.
The emphasis there on the word "medical."
The vaccine is regarded as safe for children. There have been extremely rare cases of heart inflammation called myocarditis in children in the US and other countries where the vaccine is widely used in the under 15s.
The rate of myocarditis in children after vaccination is around six in a million. The natural background rate is around six in 100,000, according the government's drug watchdog.
For children at risk of severe Covid, the benefits of the vaccine massively outweighs the potential (and far from certain) risk of an inflamed heart.
The problem is when it comes to healthy children.
For the vast majority of children, the risk of severe Covid is very rare. There's a fundamental principle in medicine that you don't give a treatment where there is no medical benefit.
The Joint Committee on Vaccination and Immunisation found that there is evidence of "marginal benefit" for all children, but it was too small to recommend its wider roll-out.
But - and it is a big one - the committee acknowledged that the vaccine could bring other, non-medical benefits to children that could readily tip the balance in favour of vaccination.
Education and welfare of children are two major factors that will weigh heavily. However, because they are a medical committee, they argued a decision on wider benefits would have to be made by others more qualified.
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The Chief Medical Officers aren't expected to make a final decision for several days, however they have firmly stated that they will only consider risks and benefits to children, not what the benefits to other age groups might be of having children vaccinated. This is an important ethical distinction.
The advice takes us into uncharted territory when it comes to vaccine policy in the UK.
The opinion of the is JCVI is even enshrined in our public health regulations: "The Secretary of State must make arrangements to ensure, so far as is reasonably practicable, that the recommendation of the JCVI is implemented."
The government will have to tread very carefully to act in the best interests of children, but also ensuring its decision is supported by solid evidence.