Vexed question of Covid vaccines for very young children: Some answers from the UK

Dr. B. J. C. Perera

MBBS (Cey), DCH (Cey), DCH(Eng), MD (Paed), MRCP (UK), FRCP (Edin), FRCP(Lon), FRCPCH (UK), FSLCPaed, FCCP, Hony. FRCPCH (UK), Hony. FCGP (SL)

Specialist Consultant Paediatrician and Honorary Senior Fellow, Postgraduate Institute of Medicine, University of Colombo, Sri Lanka. Joint Editor, Sri Lanka Journal of Child Health Section Editor, Ceylon Medical Journal

The Sri Lankan government and the Ministry of Health have embarked on a committed vaccination initiative for all those over the age of 12 years in the country. Yet for all that, currently there are many questions and concerns expressed by parents of very young children regarding COVID vaccinations for their children below the age of 12 years.

As at present, there is compelling evidence from clinical trials regarding the efficacy and safety of COVID vaccines that have been tested in children under 12 years of age. The main age group on which evidence is now available is the age group of children between five to 11 years of age. However, there is no universal programme, as yet, to vaccinate these children in a global perspective. In such a scenario, we now have definitive recommendations regarding this complex question from the United Kingdom: children aged five to 11 years in a clinical risk group, or those who are household contacts of someone immunosuppressed should be offered primary course vaccination with two 10 microgram doses of the Pfizer-BioNTech COVID-19 vaccine. Each of the shots is one third of the adult dose as that dose has been the one that has been found to be best in research studies. This recommendation is based on the children with comorbidities to safeguard themselves and vulnerable household contacts. It is quite justifiable to get these at-risk group and a group of young children who are at risk of spreading the disease to other at-risk adults in the same household vaccinated for very valid medical reasons.

JCVI has more recently reviewed evidence on the potential impact of extending COVID-19 vaccination to other children aged five to 11. Consideration was given to the health benefits of vaccination in this age group as a whole, the potential educational benefits, and the impact on National Health Services of delivering a two-dose vaccination programme to all of around five million young children of this age group in the UK.

Then on 16 February, 2022, just a few days ago, the JCVI advised in a communique to initiate a non-urgent offer of two 10 microgram doses of the Pfizer COVID-19 vaccine to ALL children aged five to 11 years of age. It advocates that two doses should be offered with an interval of at least 12 weeks between them. The main reason for this offer is to increase the immunity of vaccinated individuals against severe COVID-19 in anticipation of a potential future wave of COVID-19.

This advice on the offer of vaccination to five- to 11-year-old children who are not in a clinical risk group is recognised by the JCVI as a one-off pandemic response. As the COVID-19 pandemic moves further towards endemicity in the UK, the JCVI will review whether in the longer term an offer of vaccination to this and other paediatric age groups continues to be advised. They further state that in all instances, the offer of vaccination must be accompanied by appropriate information to enable children, and those with parental responsibility, to provide informed consent prior to vaccination.

The JCVI also states that vaccination of children aged five to 11 who are not in a clinical risk group is anticipated to prevent just a small number of hospitalisations and intensive care admissions in this population and would also provide short-term protection against non-severe infection such as asymptomatic and mild symptomatic infections that do not require hospital-based care.

Of course, the authorities also admit that the extent of these impacts is highly uncertain. They are closely related to future levels of infection in the population in the period following vaccination, these in turn being influenced by the timing, size and severity of any future waves of infection, as well as the characteristics of any new variants that may dominate future waves of infection.

The vaccination of children aged five to 11 who are not in a clinical risk group is not expected to have an impact on the current wave of Omicron infection. The potential benefits from vaccination will apply mainly to a future wave of infection; the severer a future wave, the greater the likely benefits from vaccination. Conversely, the less severe a future wave, the smaller the likely benefits from vaccination.

In formulating the current advice for vaccinating the five- to 11-year-old children, JCVI has considered evidence on:

* Potential direct health benefits and harms

* Indirect educational impacts of vaccination

* Wider anticipated opportunity costs

In comparison to the rest of the population of older age groups, evidence indicates that children aged five to 11 are at the very lowest risk from COVID-19. Rates of hospitalisation, paediatric intensive care admissions and death are lower in this age group than in all older age groups.

In addition, the high level of likely prior natural infection in this age group of children can be expected to contribute towards their natural immunity against reinfection. There are some data to suggest that natural immunity may last longer than vaccine-induced immunity against non-severe infection.

There is good evidence that the Pfizer-BioNTech COVID-19 paediatric vaccine induces a strong immune response to vaccination. The currently available vaccine was developed based on the original wild-type SARS-CoV2 virus and is less well-matched to the Omicron variant. Therefore, while the current vaccine provides good protection against non-severe infection due to the wild type, Alpha and Delta variants, protection against non-severe infection due to the Omicron variant is less good and is anticipated to be of relatively shorter duration.

JCVI has considered evidence on the educational impact of COVID-19 on children aged five to 11 years, and how the vaccination of children might mitigate these impacts. A major reason contributing towards a loss in education during the Omicron wave is the absence from school due to self-isolation in the event of SARS-CoV2 infection amongst pupils. Because most infections are mild, the duration of absence from school is likely to be mostly determined by existing self-isolation policies, rather than the duration of symptoms severe enough to require time away from school for illness recovery. However, firm data to confirm this observation are lacking.

For vaccination to have a substantial impact on absence from school, persistent high levels of vaccine-induced protection against non-severe infection are required. However, with respect to highly transmissible variants such as Delta and Omicron, currently available COVID-19 vaccines provide good protection against non-severe infections for only a limited period of time.

Estimates of the balance between absence from school due to vaccine-related reactions compared to absence prevented through reductions in infection vary depending on the likely future incidence of infection.

A day after the release of the JCVI recommendations, the Royal College of Paediatrics and Child Health (RCPCH) of the United Kingdom acknowledged that the JCVI had given careful consideration to the assessment of the benefits and risks of vaccinating the healthy five- to 11-year-old children. The RCPCH goes on to state that it is a priority that five–11-year-olds who are deemed to be at risk of COVID infection or who are living with family members who are immunosuppressed, receive this vaccine. The COVID vaccine has been certified as safe by the Medicines and Healthcare products Regulatory Authority (MHRA) of the UK, and that the RCPCH would encourage all those who are eligible to have the vaccine to consider doing so. They seem to be very supportive of the advice provided by the JCVI.

The RCPCH further states that delivering a vaccination programme to five–11-year-olds will require careful planning to ensure a favourable experience for children. Finding child-friendly vaccination sites, staffed with appropriately trained professionals, will be important and should facilitate equal access to all children which is the key to avoiding disadvantaging some families. Governments should develop information and materials that are parent-and-carer friendly, and suitable for children, to facilitate their decision making.

These initiatives and considerations undertaken by the UK agencies have a significant potential impact on the situation in our country. The UK recommendations are very sound on a scientific basis. The local authorities in our Ministry of Health and the Sri Lanka College of Paediatricians need to take cognizance of all considerations that have gone into such carefully considered advice from the UK. We should seriously consider this age group of all children of the five- to 11-year-old age group including the at-risk youngsters for vaccination against COVID-19. It would help allay anxiety on the part of parents of young children of that age group. However, once implemented, it should not be a reason to assume a blasé attitude and run around, disregarding health guidelines including physical distancing, wearing of masks and repeated washing of hands.

(This article incorporates details from a direct communication from Dr Camilla Kingdon, President, Royal College of Paediatrics and Child Health of the United Kingdom.)