There are many aspects of COVID-19 that are poorly understood, but perhaps the most surprising is the data regarding children. Usually, the “vulnerable” populations for infectious disease are the young, the old, and the immunocompromised. In the case of coronavirus, the young have been almost entirely spared. It is wonderful that kids are protecting from this disease, but this raises an obvious question…. why?
A review by Jonas Ludvigsson published March 23 has offered some of the first insights into the subject. This paper looked at 45 articles and letters on COVID-19 that related to children, and summarized the findings. The author found that only 1–5% of confirmed COVID-19 cases were age 19 or below. Given that roughly one-third of the world’s population falls into this age group, this figure is incredibly low.
Not only do children rarely catch the disease, when they are infected the symptoms tend to be very mild compared to adults. A study cited in the review found that less than 1% of hospitalizations for COVID-19 in the US were children. An early document released by the WHO estimated that 2.5% of infections in children would rate as “severe”, and only 0.2% had died.
After providing a compelling case about how resistant children are, the paper provides some theories on why children are protected. Pre-existing conditions could play a role, as children are unlikely to suffer from high blood pressure, diabetes or heart disease. Another theory suggests that children have a general resistance to COVID-19 related viruses - daycares and schools are breeding grounds for disease, which trains the immune system to fight off infections like coronavirus. Children may also be protected due to the configuration of their immune system, which changes on a biochemical level with age. Unfortunately, these are just theories for now, and we must wait for more research to advance this science.
While children are quite resistant, they are also not “immune” to COVID-19. Some otherwise healthy children have contracted severe cases of coronavirus, and some have even died. Children also play an unclear role in spreading COVID-19. Hopefully future studies can clarify why the young are so resistant, but for now we can be thankful that they are largely spared from this pandemic.
This is part of a series covering research that relate to the COVID-19 pandemic. COVID-19 medicine is an area of study that is evolving rapidly, and some of the science discussed here could end up being incorrect. Other articles in this series cover hydroxychloroquine, weather’s effect on COVID-19, the use of masks, airborne transmission and CP therapy.