Currently, children and teenagers are the only age groups in which the number of positive tests increased in mid-September. This shows that transmission rates are still high among segments of the population that have, for the most part, not been vaccinated. On 30 September, 204,000 pupils enrolled in English state schools were absent from school for Covid-related reasons. This number would significantly reduce with vaccination campaigns.
Furthermore, in recent weeks, cases have also started rising among 35- to 50-year-olds, suggesting that children are now transmitting the virus to their parents. Although there is a consensus that the risk of young children being severely affected by Covid-19 is extremely low, there is a strong case to be made as to why administering Covid vaccines to those aged 5 to 11 should be encouraged. While severe cases remain uncommon, during the first week of September, around 2 per cent of Australian children who tested positive for Covid-19 required hospitalisation. Should these numbers stay consistent while cases rise among children, it will place unnecessary strain on health services.
A study currently at pre-publishing stage in the Lancet estimates that vaccinating 5- to 11-year-olds would reduce Covid-19 deaths in the UK by 60 per cent. If trials are successful and scientific advice permits it, then vaccinating children would greatly help control transmission rates and reduce the number of vulnerable people being exposed to and dying of Covid-19.
Infection and Hospitalisation Levels
In most countries with high vaccination rates, the only age groups in which case numbers are increasing are children and teenagers, due to the fact that small numbers in these age groups are fully vaccinated. Although in most cases children experience either mild symptoms or none at all, over 2 per cent of children in the US and Australia who test positive for Covid-19 are hospitalised. If case numbers continue to rise in the UK, there is a risk that the NHS will be placed under further pressure. Below is a collection of useful data and information on cases, infections and hospitalisation in the UK, the US and other countries across the world.
In the week ending 18 September 2021, the percentage of people testing positive increased for two groups: 2-year-olds to Year 6 pupils and those in Year 7 to Year 11. In the same week, the trend was uncertain for those aged 50 to 69 and decreased in all other age groups.
The percentage of people testing positive was highest in young people at secondary school. In the week ending 18 September 2021, 2.81 per cent (95 per cent credible interval: 2.35 per cent to 3.33 per cent) of children in Year 7 to Year 11 tested positive for Covid-19. Non-vaccinated groups are testing positive at the highest rates.
On 30 September, 204,000 state-school-enrolled pupils were absent from classes due to Covid. This amounts to 2.5 per cent of pupils, and represents a two-thirds increase over a two-week period.
A study by the Lancet on UK schoolchildren aged 5 to 17 found that out of all children who tested positive, although most experienced symptoms for less than a week, 4.4 per cent experienced symptoms for 28 days or more.
Studies released in July, using data from the first 12 months of the pandemic, showed that 25 under-18s had died from Covid-19 in England, 250 required intensive care and 5,800 were admitted to hospital. Twenty-five deaths from around 12 million under-18s amounts to around two deaths per million people.
Currently, in England and Wales, positive cases in schools do not mean that the whole class is sent home, with Test and Trace working with schools to identify close contacts.
Cases have been rising since schools reopened, initially only among school-age groups. However, case increases have recently been noted among 35- to 50-year-olds, suggesting that children are now transmitting Covid-19 to older populations (see below).
Throughout the first three weeks of September, the only age groups where the number of positive Covid cases increased were children aged between 5 and 19 years old. The trend is notably highest among 5- to 14-year-olds, with over 800 per 100,000 children testing positive each week. However, since then, the number of positive cases has also increased for all age groups between 35 and 49, which suggests that children are now transmitting the virus to their parents.
There is also evidence to suggest that fully vaccinating children and teenagers, as opposed to administering single doses (which is the government’s current policy), helps to reduce the likelihood of children suffering from Long Covid in the event that they do test positive for the virus. If cases among 10- to 19-year-olds reach 1,000 per 100,000 per week (estimates place the current figure at 680 per 100,000), then fully vaccinating teenagers would prevent 4,430 hospital admissions and 36 deaths over a 16-week period, greatly reducing the strain on the NHS.
In the US, up to 2 per cent of children testing positive for Covid-19 are hospitalised, and doctors are urging child vaccination to be prioritised.
Children are now becoming the index case among households. A study in Pediatrics published in August 2020 found that in only 8 per cent of cases were children the index case (the first to catch and transmit Covid-19 to family members). However, the trend has now reversed, and children are now seemingly transmitting to the virus to their parents. Studies using public health data in Ontario, Canada, shows that children and teenagers are increasingly likely to be the primary case in households.
Rest of World
In Australia, 2.7 per cent of children up to the age of 9 testing positive for Covid-19 are hospitalised, with that figure rising to 2.9 per cent among 10- to 19-year-olds.
“Children under 10 were roughly half as likely as adults to spread the virus to others, consistent with other studies. That may be because children generally exhale less air – and therefore less virus-laden air – or because they exhale that air closer to the ground, making it less likely that adults would breathe it in.” – New York Times article on a study in Korea about the risk of school re-openings causing clusters. Although children are less likely to spread the virus, the risk remains. Vaccinating 5- to 11-year-olds would greatly reduce this risk.
When state-level interventions on vaccines (for 12- to 17-year-olds) and masks are implemented, schools are not the most likely source of infection for children. However, when measures are not enforced, then schools do become the dominant location where children become infected with the virus. Essentially, mask-wearing and vaccine mandates greatly reduce transmission in schools.
In France, the number of children testing positive for Covid increased tenfold between the start of July and the end of August. Emmanuel Macron said at the start of September that when scientific bodies give the green light, he will be ready and willing to begin a vaccination campaign for 5- to 11-year-olds.
Medical Advice, Studies and Trials
Recently, medical advisors and paediatricians have voiced their support for making vaccinations available for younger children. Pfizer has announced encouraging results from their trials on child vaccinations, at lower doses, and will seek approval from national and international regulators imminently. Vaccine manufacturers Moderna and Johnson & Johnson are currently trialling, or intend to trial, vaccines for younger children.
Pfizer has announced that one dose is safe for 5- to 11-year-olds, and has made public its intention to seek the Food and Drugs Administration, the European Medical Agency and other regulatory bodies’ approval before the winter. Each vaccine contains less than 3 micrograms per dose, compared to 10 micrograms in vaccines administered to adults, which shows the precautions being taken by the pharmaceutical companies producing vaccines.
Pfizer has also been trialling vaccinations on two other age groups (6 months to 2 years, and 2- to 5-year-olds). Data and reports are expected to be released by the end of the year.
Trials by Pfizer show robust antibody levels in vaccinated children. Children were administered two doses, each containing one-third of what adults receive (10 micrograms instead of 30), three weeks apart. Immune systems are not weight dependent, which explains why all children are given the same smaller dosage than adults and teenagers.
Moderna is also in the process of trialling its vaccine on primary-school children.
Johnson & Johnson is currently conducting trials with teenagers aged 12 to 17 but intends to start trialling a vaccine for 5- to 11-year-olds.
Pfizer Vice-President Dr Bill Gruber, a paediatrician, announced that children tested experienced a similar amount, or even fewer temporary symptoms – such as fever, aches and sore arms – than teenagers experienced.
Currently, Pfizer’s vaccine has not been trialled on large enough groups to make estimations on possible long-term side effects such as heart inflammation amongst young men.
The rate of myocarditis (a rare inflammation around the heart, easily treatable when diagnosed) is twice as high for 12- to 15-year-olds than for 20- to 24-year-olds. Whether or not this would increase for younger children remains to be seen. This being said, myocarditis is more likely to occur after contracting Covid itself than from receiving the vaccine.
However, parents will be eager to know the vaccine is safe before letting their children receive it. Dr David Strain, who co-authored the upcoming Lancet paper on how vaccinating children will reduce hospitalisations, said that he is unsure about whether he would have his children vaccinated when instead people could just work from home and wear masks. This illustrates the nuanced and sensitive nature of the topic, and emphasises the need for clear proof that children will not suffer adverse effects after receiving the vaccination. If these fears are not allayed, parents will choose not to have their children vaccinated and uptake will be low.
In a previous paper (Pandemic to Endemic), the Institute advocated for 12- to 15-year-olds to be fully vaccinated (as opposed to single doses being administered – which is the government’s current policy). We also support the idea of vaccinating 5- to 11-year-olds, but only if the science shows evidence that the benefits of vaccinating them safely largely outweigh the possible risks involved.
The reasoning for supporting vaccination of children derives from the idea that we must protect vulnerable populations from infection, and reduce transmission rates in general. We acknowledge that children are at low risk from serious Covid complications, but they can still transmit the disease – including when asymptomatic – so vaccinating them would protect the older populations they interact with, especially if there is low take-up for booster programmes.
Vaccinating 5- to 11-year-olds should be authorised in the medium term due to the fact that this would greatly reduce transmission, and therefore limit the number of vulnerable people being exposed to Covid-19.
As specified in the Institute’s previous Pandemic to Endemic paper, mask mandates should be reintroduced as an interim measure in specific contexts, including public transport, largescale indoor events, and while interacting with vulnerable family members. These mandates should be in place until all children aged between 5 and 11 have been fully vaccinated, in order to protect them from infection and reduce transmission rates. Furthermore, all teenagers (aged 12 to 17) should be fully vaccinated and not merely receive one dose, as recent data has demonstrated that fully vaccinating teenagers would prevent thousands of cases of Long Covid. Currently, the government has only sanctioned the administration of one dose for 12- to 15-year-olds.