School-related Covid-19 clusters have increased substantially in Malaysia since the opening of schools, especially with the most recent Omicron surge.
Most children who are infected have stayed asymptomatic, but they may easily transmit the virus to others, including those who are at higher risk of severe diseases.
According to CovidNow, children aged 5 to 11 made up about 10 per cent of the country’s total Covid-19 cases in recent weeks, and it is predicted that the incidence for younger children is likely to increase further.
Following vaccination drives for adults and adolescents, Malaysia has rolled out a Covid-19 vaccination programme for children. Many countries such as the United States, Canada, Germany, Austria, Belgium, Hungary, Greece, Singapore, and Indonesia have started vaccination for children aged 5 to 11, beginning late 2021.
Many parents in Malaysia are concerned about the safety profile of the Pfizer-BioNTech vaccine for younger children, and so we have laid out some findings of various studies on the efficacy and safety of the vaccine for this age group.
In preauthorisation clinical trials as reported by the US’ Centers for Disease Control and Prevention (CDC), the Pfizer-BioNTech vaccine was administered to 3,109 children aged 5 to 11, and most adverse events were mild to moderate such as pain at the injection site, headaches, and mild fever.
No serious adverse events related to vaccination were reported during these trials. the CDC reviewed adverse events after receipt of Pfizer-BioNTech vaccines reported to the Vaccine Adverse Event Reporting System (VAERS), from November 3 to December 19, 2021.
Approximately 8.7 million doses of this vaccine were administered to children aged 5 to 11 during this period, and VAERS received 4,249 reports of adverse events after vaccination for this age group, of which 97.6 per cent were not serious.
There has also been some concern over cases of myocarditis and pericarditis following the administration of mRNA vaccines. Myocarditis is a rare but serious adverse event that has been associated with mRNA-based vaccines; reporting rates for vaccine-associated myocarditis appears highest among males aged 12 to 29.
To date, myocarditis among children aged 5 to 11 appears very rare, with approximately 11 cases in 8.7 million.
Myocarditis has been well described long before the pandemic. It can occur when a virus, such as the common cold, influenza, or SARS-CoV-2 (the virus that causes Covid-19) infects the body.
Fortunately, current studies show that post-vaccine-related myocarditis is typically much milder than classic myocarditis due to viral infection, with symptoms lasting for a shorter amount of time, and usually resolving with minimal, if any, medical treatment.
In two recently published randomised controlled trials on Pfizer-BioNTech vaccines for children and adolescents, the investigators reported that the vaccine achieved over 90 per cent reduction in the risk of contracting Covid-19 for children aged 5 to 11, as well as adolescents, with no serious adverse events such as myocarditis observed in the period of the study(2, 3).
However, as with adults, mild reactions such as injection site pain, fatigue, and headache were reported. Parents and guardians of children aged 5 to 11 vaccinated with the Pfizer-BioNTech vaccine should be informed of the possibility of such reactions after vaccination, probably more likely after the second dose. The parents should also advise the child to avoid strenuous exercise up to a week after vaccination.
Some parents are considering opting out of vaccinating their children in the hope of depending on herd immunity. Traditionally, herd immunity is achieved when 80 per cent of the population have been fully immunised against an infection.
But this is not so with Covid-19, especially with the new Omicron variant, as the estimates will become much higher. We will likely need more than 95 per cent of the population fully immunised to achieve a degree of protection similar to that conferred by herd immunity(4). Currently, our population of those immunised stands at 79 per cent.
Furthermore, herd immunity is also a dynamic phenomenon that depends on the movement of the herd. Let’s say if a family has five adults and one child, and all adults are immunised, then one can say that the family has herd immunity—provided that the family live in the same house all the time, and the child never spends any time outside.
If the child goes to school, the majority of the population are children. If all children who are not immunised congregate there, there is no herd immunity in that setting.
This may be exacerbated if there are parents adopting a ‘wait and see’ approach to children’s vaccinations because of worries over its current and long-term side effects. However, we will not be able to achieve the 95% of immunisation rate to gain herd immunity if we do this.
The danger of depending on herd immunity is if most parents decide to not immunise their children, then it will be certain that there will not be just a few selected few who opt not to be immunised.
This will spell big trouble for the general level of immunity among children. Consequently, the risk of children contracting the virus, particularly with more contagious variants like Omicron, is significantly higher.
Rest assured, from the data available, the chances of developing severe side effects from the vaccine in this age group are very rare.
The current phenomena of an apparently milder course of illness when one contracts the Omicron variant is the result of having our immunity propped up by vaccination.
The illness will certainly be more serious across the population if we are not vaccinated. Some believe we should now be treating Omicron like a normal flu, but we would advise not to let our guard down just yet.
Vaccination is still the most effective way to prevent Covid-19 infection, and the development of serious complications, including the likelihood of reduced transmission at home and in school, to safeguard vulnerable persons, and create a safer in-person learning environment.
Without effective vaccines for this age group, children could potentially become ongoing reservoirs of infection and sources of newly emerging variants. Widespread vaccination across age groups is therefore essential in ongoing efforts to curtail the pandemic.
In the nutshell, children aged 5 to 11 are encouraged to be vaccinated against Covid-19. Nevertheless, if the child has any pre-existing medical condition or any parents who are in doubt should seek advice from their general medical practitioner or paediatricians.
- Hause AM BJ, Marquez P, et al. COVID-19 Vaccine Safety in Children Aged 5–11 Years — United States, November 3–December 19, 2021. MMWR Morb Mortal Wkly Rep. 2021;70:1755–60.
- JR S. COVID-19 vaccine safety updates:Primary series in children and adolescents ages 5–11 and 12–15 years, and booster doses in adolescents ages 16–24 years. Advisory Committee on Immunization Practices, January 5, 2022 [Internet]. 2022. Available from [Link].
- Frenck RW, Jr., Klein NP, Kitchin N, Gurtman A, Absalon J, Lockhart S, et al. Safety, Immunogenicity, and Efficacy of the BNT162b2 Covid-19 Vaccine in Adolescents. The New England journal of medicine. 2021;385(3):239-50.
- Walter EB, Talaat KR, Sabharwal C, Gurtman A, Lockhart S, Paulsen GC, et al. Evaluation of the BNT162b2 Covid-19 Vaccine in Children 5 to 11 Years of Age. 2021;386(1):35-46.
- Omer SB, Yildirim I, Forman HP. Herd Immunity and Implications for SARS-CoV-2 Control. JAMA. 2020;324(20):2095–2096. doi:10.1001/jama.2020.20892
Dr Lim Yin Sear is a senior lecturer at the School of Medicine, Taylor’s University, and Dr Noor Hafiza Noordin is the head of the Pediatrics Department at Hospital Banting.
- This is the personal opinion of the writer or publication and does not necessarily represent the views of Ova.