In 2020, children represented only a small proportion of COVID-19 cases worldwide. The Delta strain has increasingly infected children and young people in 2021 as it has become the dominant strain around the world.1
Delta spreads faster and much more easily than other strains of the virus. According to the US Centers for Disease Control and Prevention (CDC), this variant is more than twice as contagious as previous variants.
According to Professor Kristine Macartney, “the Delta variant is more transmissible and is resulting in a greater number of COVID-19 cases among children and young people.”3
A study completed by Australia’s National Centre for Immunisation Research and Surveillance found that the high transmissibility of the Delta variant resulted in a five times increase in its spread in schools, early childhood education and care services, and households compared with the original strain in 2020.3
In New South Wales, Australian Capital Territory and Victoria, case numbers among young people made up a significant proportion of the outbreak of the Delta variant in 2021. This includes children under the age of 5.
To 30 September 2021, the number of confirmed cases reported to the National Notifiable Diseases Surveillance System was:
· 12,387 cases in those aged 0-9
· 14,792 cases in those aged 10 to 19
· 22,780 in those aged 20 to 29
The total of 49,959 represents nearly half (47.5%) of 105,123 total cases recorded in Australia since January 2020.4
Data from the United States paints a similar picture. Around 14% of all COVID-19 cases in children since the start of the pandemic were recorded in the four weeks to 30 September 2021.5
One of the reasons for this could be the lower levels of hygiene, and the inability to social distance, among children. For these reasons, children “could be more likely to spread infection once they have got it,” said Dr Robert Booy.6
Fortunately, children remain less likely to experience severe symptoms, serious illness or die from COVID-19. Data from 1 January to 1 August 2021 shows that only 2.5% of children aged 0-9 and 2.9% of children and teenagers aged 10-19 who contracted COVID were hospitalised. This is compared to 7.7% of young adults aged 20-29, with the rates continuing to increase with age.7