All the participants had either mild symptoms, such as cough and fever, or had no symptoms.
IgG is the most prevalent antibody in humans and it can indicate an individuals immunity to certain pathogens.
The researchers found that only 37% of children produced antibodies, compared to 76% of adults.
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Each group had similar viral loads and factors like age and sex didnt seem to impact individuals antibody levels.
This may mean that children are less likely to produce antibodies against COVID-19 and therefore more vulnerable to reinfection.
How Do Pediatric and Adult Immune Responses Differ?
Scientists have long known that children tend to have more reactive innate immune responses.
Adults who had symptomatic COVID-19 in the Australia study had 3-times higher IgG levels than asymptomatic adults.
But between asymptomatic and symptomatic children, there was no significant difference.
How Well Protected Are Children Against Reinfection?
A lack of these long-term immune cells could potentially leave them vulnerable to reinfection.
However, we should not discount other parts of the immune system that can also respond to the infection.
For instance, cellular immunity, which doesnt include antibodies, may play a key role.
Children may also have a more robust response from the immune cells in the mucosa of the respiratory tract.
This study only accounted for individuals who were infected with the original COVID-19 strain.
Further research will help scientists better understand how children mount antibody responses to more recent variants.
Vaccination is still the best way to protect children from COVID-19 infection and outcomes like long COVID.
