Corona Daily 315: Sophie’s World and the Coronavirus

One of the several mysteries of the current pandemic is the way it has spared children so dramatically. The number of infections among children, as compared to adults, is tiny. This phenomenon is uniform across all countries. A major study headed by Dr Betsy Herold published its results this week. When reading it, I was reminded of the novel Sophie’s World.

*****

Sophie’s World by Jostein Gaarder, a Norwegian writer, is a philosophy textbook disguised as a novel. Highly readable, this bestselling book introduces the reader, along with Sophie, to the history of philosophy.

In one place, the book talks about a toddler, who sees and hears a dog bark for the first time. The one-year old is excited, perhaps alarmed, because it has never seen a barking dog before. If the toddler were to see an apple shooting up from the ground to the tree, or its mother walking on the ceiling, it would not be shocked; it would simply store these new experiences. In that sense, pre-school children have a very open mind, because they haven’t yet learnt gravity in school. Children have no preconceived opinions. A child’s mind is a Tabula Rasa (clean slate).  

Adults however, become slaves of the expectations of habit based on their experiences and education. A barking dog is not an event to pay attention to, and if a magician makes an apple fly, they know it is only a trick of some kind.

*****

Dr Herold’s team studied 60 adults and 65 children (age under 24) in a New York hospital from March to May.

The study finds that the children’s “innate immune defence” is rapid and overwhelming. Compared to adults, children have experienced few viruses. As soon as a child’s immune system confronts the coronavirus, it becomes alert and starts fighting with all force.

Human beings have two types of immunity – innate and adaptive. Adults, over time, have experienced a series of viruses; their systems carry a large database of the pathogenic villains. Their response, called the “adaptive response”, is more virus-specific. The adaptive immunity tries to create antibodies and immune cells to target the particular virus.

Apoorva Mandavilli, in her New York Times article compares the children’s immune response to an ambulance that immediately starts working on the patient. The adults’ adaptive response is like that of the skilled specialists at the hospital.

By the time the adult gets the adaptive system up and running, the virus gains valuable time to inflict harm. In older adults, the innate system fades making them more vulnerable.

*****

This is not a speculative hypothesis. The children studied had much higher blood levels of two particular immune molecules – interleukin 17A and interferon gamma. The largest quantities were found in the youngest patients. Quantities declined progressively with age.

All viruses have their inbuilt tricks to evade the innate immune system, and the novel coronavirus is known to be particularly skillful. By producing interleukin-17 early in the course of infection, children seem to successfully defeat the virus’s attempts to avoid the innate response.

Dr Herold noted that most existing vaccine candidates focus on boosting the neutralizing-antibody levels. She suggests developers should consider vaccines that can promote immunity by bolstering the innate immune response.

*****

Adults, alas, can’t be children any more. But they can try to mimic how children defend themselves against the novel coronavirus.

Ravi