With schools shutting down and restrictions being placed on movement, children have suffered a lot over the last one and a half years. There is a lot of debate now on administering COVID-19 vaccines to children in the context of schools reopening in India. As practising scientists and concerned parents, we have followed scientific literature on these topics. Any medical intervention, specifically for children, should involve a careful risk-benefit analysis. What is the risk of children being affected by COVID-19? Is the risk of the vaccine guaranteed to be lower than this? Are trials designed to uncover rare risks? What about long-term risks? We seek to explore these questions.
The risk of severe outcomes due to COVID-19 in children is very rare , and chance of death is extremely low (about two in a million). Even children who were severely affected were found to have chronic conditions. These facts have not changed even with the Delta variant. Numbers may not make much sense since we are emotional about children. So, to understand the risk, consider the following comparisons. For a child, the likelihood of succumbing to COVID-19 is about the same as being hit by lightning . For those aged below 25, the risk of traffic accidents or even suicide is about 10 times higher than death due to COVID-19. Even the risk of long-lasting COVID-19 symptoms is very rare in children.
Now, let’s compare this with the risk posed by vaccines. While the risk of the current COVID-19 vaccines is certainly low, it is not nil. This is relevant since the risk of severe COVID-19 is low in children. Both serious adverse effects and vaccine-related deaths in adults have been reported all over the world , including in India. Based on a risk-benefit analysis, Australia , the U.K., and many European countries have not recommended AstraZeneca (Covishield) for children. The only vaccines in use for 12+ are the Pfizer/BioNTech and Moderna vaccines, and these too put children at risk of myocarditis (inflammation of the heart muscle). A recent study from the U.S. reported a one in 6,000 risk of cardiac adverse event risk from the Pfizer vaccine for boys aged 12-15; similar numbers have been reported from Israel and Canada too. That such findings are coming after having vaccinated millions of children is worrying.
Long-term safety not assured
Aside from the short-term effects, there is the question of long-term safety too. All the current COVID-19 vaccines being rolled out have only limited short-term safety data; clinical trials will go on till 2023. It may take a few years to start seeing long-term effects. Further, the Pfizer and Moderna vaccines use a new gene-based technology (mRNA) different from prior vaccine technology. The long-term safety of this new technology itself is unknown. These aspects have to be juxtaposed with the low risk children face from COVID-19: there is/was no COVID-19-related medical emergency for children.
An aspect underlining the significance of the issue of long-term safety is that all the COVID-19 vaccine manufacturers have been granted zero liability. An AstraZeneca senior executive explained why pharmaceutical companies have requested zero liability: “This is a unique situation where we as a company simply cannot take the risk if in…four years the vaccine is showing side effects.”
The importance of long-term safety is further stressed by the fact that the past history of ‘emergency vaccines’ is not all rosy. The swine flu vaccine, Pandemrix, was rolled out in response to the 2010 pandemic. It was later withdrawn when it was found that around one in every 55,000 jabs led to narcolepsy (a chronic sleep disorder) in children. Dengvaxia, a vaccine against dengue, was withdrawn in 2017 after 19 children (1 in 44,000) died of possible antibody-dependent enhancement.
A crucial aspect to consider in the context of safety is the size of the current vaccine trials. It is pertinent to note that some of the risks for adults did not show up during the adult trials (for example, given the trial size of 32,449 for AstraZeneca, blood clots as a result of the AstraZeneca vaccine, which is a one in 50,000 chance, could not be detected). In India, the current trial sizes for children are just 525 for Covaxin and 1,000 for ZyCoV-D . These are abysmally low and insufficient to catch even, say, a one in 1,000 side-effect risk. This is extremely concerning.
Even though children and young adults are not at high risk from severe COVID-19 (unlike adults), some countries like France and Germany have allowed all those above 12 years of age to be vaccinated in the hope that this will prevent community transmission and lead to herd immunity via vaccination. However recent data are increasingly showing this to be scientifically wrong as the current vaccines neither prevent infection nor transmission. This is evidenced by high case counts even in highly vaccinated countries such as Israel and Iceland . Furthermore, it is morally wrong to put children at risk (without assured long-term vaccine safety) to protect adults, especially when those adults anyway have access to a COVID-19 vaccine that is effective against hospitalisation/deaths. Indeed, the U.K. decided “not to recommend the vaccine to all healthy children” given the lack of clear benefits for them.
Since the risk of severe COVID-19 is low in children, the medical benefit of COVID-19 vaccination for children is questionable, and the lack of studies on long-term safety as well as small trial sizes are concerning. COVID-19 vaccines for children may be warranted in exceptional cases, such as for those with other co-morbidities who are at higher risk from COVID-19. In any event, parents have the best interests of their children in mind. Given that vaccinations are an irreversible medical procedure, parents should do due diligence before vaccinating their children: examine all available evidence, ask pertinent questions to experts and then make an informed choice. Vaccination should also not be mandated; parental choice is critical.
Time to open schools
There has been recent talk of tying school reopening to children’s COVID-19 vaccines. There is no scientific basis to this as schools were opened safely in most other countries, often before vaccine trials were under way. Further, sero-surveys show that a large percentage of children have already been exposed to COVID-19: we just did not notice it since severe COVID-19 is very rare in children. And it is not that vaccines are readily available in India (Covaxin and ZyCoV-D are still under trials). Uptake among those who wish to take it will take many months. How long can we keep schools shut? The vast majority of parents who want to send their children to school should have the option to do so. We have the ignoble distinction of being one of the few countries which have not yet fully opened schools, while over 175 countries have opened schools with safety protocols prioritising children’s education and safeguarding their country’s future.
Kameswari Chebrolu and Bhaskaran Raman are faculty in the Department of Computer Science and Engineering at IIT Bombay. Views are personal