More than 1.5 million children worldwide saw a parent, custodial grandparent or other relative who cared for them die from the coronavirus disease 2019 (Covid-19), according to a study published Tuesday by the Lancet.

Of these children, more than 1 million children had one or both parents die during the first 14 months of the pandemic, and another 500,000 experienced the death of a grandparent caregiver living in their own home, the data showed.

“By April 30, 2021, these 1.5 million children had become the tragic overlooked consequence of the 3 million Covid-19 deaths worldwide, and this number will only increase as the pandemic progresses,” study co-author Susan Hillis said in a press release.

“Our findings highlight the urgent need to prioritize these children and invest in evidence-based programs and services to protect and support them right now and to continue to support them for many years into the future,” said Hillis, an epidemiologist with the CDC in Atlanta.

Before the start of the pandemic in March 2020, there were an estimated 140 million orphaned children worldwide, World Without Orphans estimates.

These children are at increased risk for mental health problems, family poverty and physical, emotional, and sexual violence, and they are also more likely to die by suicide or develop a chronic disease, including heart disease and diabetes, according to the organization.

For this study, the researchers developed mathematical models using the best available data to estimate the number of children impacted by the death of a parent or guardian during the pandemic.

They based their Covid-19 orphanhood estimates on mortality data for 21 countries that collectively account for 77 percent of global Covid-19 deaths, they said.

The analysis included both reported Covid-19 deaths between March 1, 2020 and April 30, 2021 and the number of excess deaths during the same period.

Covid-19 death rates were linked with fertility data for males and females from the 21 countries to estimate the number of children who had lost a parent to the virus, and the death of both parents was accounted for so that children were not counted twice.

Grandparents not spared

The analysis also included deaths of grandparents or other older adults age 60 to 84 who were living in the same household as the children to account for custodial grandparents who have primary responsibility for their grandchildren’s care.

At least 1.134 million children experienced the death of their mother, father or custodial grandparents due to Covid-19, the data showed.

Of these, an estimated 1.042 million lost their mother or father or both.

More than 1.5 million children are estimated to have experienced the death of at least one parent or a custodial or other co-residing grandparent or other older relative, they said.

The United States was amongst the countries with the most children – nearly 114,000 – who saw the death of a primary caregiver and a per capita rate of one child per 1,000 people in the general population.

These are likely underestimates, the researchers said, because figures for a number of countries included in the study were based on Covid-19 mortality only and excess death data were unavailable.

For almost every country, deaths were greater in men than women, particularly in middle and older ages, and up to five times more children lost their fathers than lost their mothers.

“Our study establishes minimum estimates — lower bounds — for the numbers of children who lost parents or grandparents,” study co-author Dr. Juliette Unwin said in a press release.

“In the months ahead variants and the slow pace of vaccination globally threaten to accelerate the pandemic, even in already incredibly hard-hit countries, resulting in millions more children experiencing orphanhood,” said Unwin, a research fellow in medicine at Imperial College London in England.