As the world reels under the coronavirus outbreak which has over 1,18,000 confirmed cases globally, it is quite noticeable how there are very few cases of children being affected by COVID-19 compared to adults and the elderly. Out of the 61 cases in India, there are only two children who have been detected with coronavirus – a three-year-old in Kerala and a 13-year-old in Bengaluru. Cases of children have been detected elsewhere also, like the US and Italy. And the youngest to be diagnosed with coronavirus disease was an infant who was 30 hours old in China.
The Chinese Center for Disease Control and Prevention analysed 44,672 confirmed cases of the novel coronavirus till February 11, 2020, and found that less than 2% of the cases affected were those under 19 years of age, compared to 87% cases in the 30-79 age group. Further, there have been no fatalities in the 0-9 age group in China, compared to the 21.9% fatalities in the 80+ age group. The overall mortality rate for coronavirus as per the World Health Organisation (WHO), as of March 3, 2020, is 3.4% – higher than the initial calculation of 2%.
So, are children somehow less likely to contract COVID-19? Or are there less cases being detected? Here is what experts and existing research say so far.
If those affected are between 1.5 months to 17 years old, the symptoms are likely to be milder, research has shown. Children in this age bracket in China were found to be asymptomatic or manifested with fever, dry cough, and fatigue, and a few respiratory symptoms such as runny nose. Adults however show more severe symptoms. The research showed that most children in the given age group also recovered in one to two weeks.
While research on understanding and tackling the novel coronavirus is still ongoing, some experts say that children being less affected could have less to do with the virus and more to do with the host.
Esper, who studies viral respiratory infections and new diseases, told Washington Post that the effects of coronavirus are more severe when people have underlying health issues such as diabetes, cardiovascular diseases, or hypertension, among others. And compared to adults, fewer children have these conditions. Further, children’s lungs have been exposed for lesser time to pollution, cigarette smoking and other pollutants.
However, children with underlying health conditions like asthma are more likely to be worse affected by COVID-19.
Research in Texas also indicates that there could be immunological factors at play that could be protecting children from the novel coronavirus’s more severe effects. Research on mice at the University of Texas Medical Branch shows that while the babies recover well from SARS, the infection affects adult mice in a much worse manner. SARS also belongs to the coronavirus family.
Vineet Menachery, a virologist, told Washington Post that that the older mice’s immune systems have a dysregulation which causes higher fatalities because their immune system “overreacts to the SARS virus”, reacting aggressively, and causing more damage than the infection.
Another expert, Dr MacDermontt also told BBC that it was strange that children’s immune systems were not going into overdrive if they are affected by COVID-19. Given that children’s immune systems are still immature and overreact to infections, leading to frequent high fevers in kids, this behaviour around novel coronavirus is something worth studying.
A study published in The Lancet, a medical journal, also hypothesizes that “biological differences” could be behind children being less affected. Further, children may have developed immunity as they are affected by some other coronaviruses like ones that cause common cold. “Previous immunity from infection with a related coronavirus has been speculated to potentially protect children from SARS, and so might also have a role in COVID-19,” the study says – a possible reference to how the 2002 SARS outbreak also affected very few children (only 80) as compared to adults, with no fatalities among children.
Given that children are either asymptomatic or showing milder symptoms, it is also likely that we aren’t seeing as many cases of children being affected because they are not being reported enough.
Further, some reports also point out that a major portion of those who tested positive for COVID-19 were travellers, and are automatically adults. Most of the cases reported of children in China are those who got it within the household from another affected person.
When it comes to adults affected by coronavirus disease, we know that someone who is asymptomatic could nevertheless be a carrier of the disease and transmit it to someone else. During the SARS outbreak though, there was reportedly only one published report of someone getting SARS from an affected child. However, we do not know enough about the novel coronavirus yet to say if children are less likely to transmit it also, which is why children should also come in ambit for taking precautions.
Meanwhile, Some research has also shown that children exposed to coronavirus are just as likely to contract it as the general population, even though they may show milder symptoms.
Regardless of what the reasons behind children reporting with fewer coronavirus cases are, it is a good thing. If more children were affected, the virus’s spread would also hasten, considering children are less likely to be careful about precautionary measures like washing hands, and covering their nose and mouth while coughing or sneezing.