Spending less time outdoors and more time looking at screens during prolonged school closures brought on by the pandemic, school-aged children are at risk of experiencing a substantial myopic shift due to the home confinement resulting from COVID-19, according to a new study published in JAMA Ophthahlmology.

“Younger (aged six to eight years) children’s refractive status may be more sensitive to environmental changes than older children, given that they are in an important period for the development of myopia,” the researchers wrote in their paper.

They launched a prospective, cross-sectional study of school-based photoscreenings (noncycloplegic photorefraction) that included 389,808 eyes of 123,535 children aged six to 13 from ten elementary schools in Feicheng, China. About half of the students were boys.

The researchers noted a substantial shift in myopia prevalence in the 2020 screenings compared with preceding years for younger children (Table 1). These differences were minimal in children aged nine to 13 years.

“This substantial myopic shift was not seen in any other year-to-year comparison,” the researchers concluded. They say that “the cause [is] possibly due to the unusual occurrence of home confinement in 2020.”