Why aren’t kids getting vaccinated?
While much of the world is engaged in a frantic scramble to get vaccinated against covid-19, there’s one group noticeably absent from the queues of people at vaccine clinics: children.
The Pfizer-BioNTech vaccine is still approved for use only in those aged 16 years or older, and the Moderna vaccine is only for adults. Both are now in trials for younger age groups, and results are expected by the summer. The Oxford-AstraZeneca and Johnson & Johnson vaccines are also due to start trials in children soon. But in a world where most vaccines are given to children under two, why is it that during a global pandemic, children are being left behind? And what does it mean for how the pandemic will unfold in adults?
One reason children are not yet priorities for vaccination is that they are much less affected by SARS-CoV-2 infection than adults. Children make up nearly 13% of all cases reported in the United States so far, but less than 3% of all reported hospitalizations and less than 0.21% of all covid-19 deaths. When they have symptoms, they are similar to adults’—cough, fever, sore throat, and runny nose—but less severe.
Even a year into the pandemic, it’s not yet entirely clear why this is the case. Research points to a different immune response to viral exposure in children, which may signify that their immune systems are able to neutralize the virus much faster and therefore stop it from replicating. Children may also benefit from cross-protection by antibodies to other circulating coronaviruses that they are more regularly exposed to.
And there’s also the possibility that children have fewer ACE2 receptors in the cells that line nasal passages, which are the doorways the SARS-CoV-2 viruses uses to gain entry to host cells and infect them. That would make it less likely for the virus to get a foot in the door. There is a more serious complication of SARS-CoV-2 exposure that can occur in children, called multisystem inflammatory syndrome in children, or MIS-C. However it is rare, with fewer than 1,700 cases and just 26 deaths reported across the US.
Children’s apparent resilience to covid-19 makes them a lower priority for vaccination, especially when demand for vaccines far outstrips supply.