Long Covid may affect 5.8 million children in the U.S., according to an article published on Wednesday in the journal Pediatrics. That’s a large number. It’s also a number that stands in contrast to other published estimates of pediatric long Covid. So, who’s right?
Let’s begin by exploring how the authors of this article arrived at their number. As with any estimate, they started with a few basic assumptions. They assumed that 20% of Covid-19 cases occur in children and that the prevalence of long Covid, or postacute sequelae of SARS-CoV-2, in children is 10-20%.
According to data provided by KFF, the cumulative number of Covid-19 cases in the U.S. at the end of January 2024 was approximately 105 million. If 20% of those cases occurred in children and 20% of those children developed long Covid, then about 4.2 million children in the U.S. should be affected. That’s reasonably close to the number cited by the authors. However, it’s unclear how the authors determined that 10-20% of children with Covid-19 will develop long Covid. They state that experts, “reviewed the literature for relevant pediatric studies and summarized the findings.” That’s all we really know. They list 98 articles that were reviewed. Presumably, their careful review of these articles led the authors to determine that the prevalence is 10-20%. But we don’t have any information about why these articles were selected and, conversely, why other articles may not have been selected.