At least 5.2 million children have lost a parent or caretaker to Covid-19, study estimates

(CNN) At least 5.2 million children globally have lost a parent, grandparent or family member who helped care for them to Covid-19, a new study says.

The study, published Thursday in the medical journal The Lancet Child & Adolescent Health, looked at Covid-19 mortality data from 21 countries from the start of the pandemic in March 2020 through October 2021 and estimated the number of children who lost a parent or caregiver. The number of children affected rose by 90% from the end of April 2020 to the end of October 2021.

The study follows an earlier analysis While beyond the scope of the study, real-time data using the same model suggest that the number of kids who lost a parent or caregiver is around 6.7 million as of January. This "heart-breaking hidden pandemic," as the authors call it, has outpaced the total number of Covid-19 deaths, according to World Health Organization totals. The study follows an earlier analysis published in July . The authors said they felt they needed to update it because of "the proliferation of new coronavirus variants, updated mortality data, and disparities in vaccine access increased the amount of children experiencing Covid-19-associated orphanhood."

The authors -- including researchers from the US Centers for Disease Control and Prevention, USAID, the World Bank, University College London and elsewhere -- believe their estimate is conservative. Many countries lack a robust reporting system for deaths. Covid-19 death in Africa, for example, are believed to be 10 times higher than what is known.

Of the children that lost parents, three out of four lost their fathers. Preteens and teens were the most likely to be orphaned with two out of three children that lost a parent being an adolescent. Earlier studies showed in the US, racial and ethnic minority communities were disproportionately impacted by this loss.