Over 1 million children in the US have not enrolled in schools, with the sharpest drop in kindergarten, more than 340,000 students, as the COVID-19 pandemic has continued to sweep the country, a media report said.

The children who had been expected to enrol in local schools did not show up, either in person or online, and the missing students were concentrated in the younger grades, Xinhua news agency quoted The New York Times report published on Saturday as saying.

The report added that besides triggering vast disparities in health care and income, the pandemic also "hardened inequities in education, setting back some of the most vulnerable students before they spent even one day in a classroom," according to an analysis of enrolment at 70,000 public schools across 33 US states.

The analysis by the New York Times in conjunction with Stanford University shows that in the 33 states, 10,000 local public schools lost at least 20 per cent of their kindergartners.

In 2019 and in 2018, only 4,000 or so schools experienced such steep drops.

The survey also showed that the steepest student enrolment drop was in the households below or just above poverty line, adding that the decline was 28 per cent larger in schools in those communities than in the rest of the country.