More than 1.5 million children across the globe have lost a parent or caregiver during the first 14 months of the pandemic, according to a new study.

In a study published by The Lancet medical journal on Tuesday, the researchers estimated that 1,562,000 children have experienced the death of at least one parent or a custodial or other co-residing grandparent, or other older relative.

"The COVID-19 pandemic priorities have focused on prevention, detection, and response. Beyond morbidity and mortality, pandemics carry secondary impacts, such as children orphaned or bereft of their caregivers," the study said.

The estimates were developed using excess mortality and COVID-19 deaths for 21 countries that accounted for more than 76.4 percent of global COVID deaths up to April 30, 2021. These include Argentina, Brazil, Colombia, England and Wales, France, Germany, India, Iran, Italy, Kenya, Malawi, Mexico, Nigeria, Peru, Philippines, Poland, Russian Federation, South Africa, Spain, United States, and Zimbabwe.

The researchers predict that many more children will experience such losses as the pandemic continues.

"Children losing primary caregivers have higher risks of experiencing mental health problems; physical, emotional, and sexual violence, and family poverty," the study said.

It added that these traumatic experiences are associated with increases in substance use, suicide, infectious diseases such as HIV/AIDS, adolescent pregnancy, and chronic health conditions.

“These unnamed children are the tragic overlooked consequence of the millions of pandemic dead,” the researchers wrote.

The magnitude of parent and caregiver loss in COVID-19 also shows an urgent need for ensuring equitable global access to vaccines, along with evidence-based programs and services, the researchers added.

The study was led by various experts from Centers for Disease Control and Prevention, World Health Organization, United States Agency for International Development, World Bank, University of Oxford, Imperial College London, Harvard University, and University College London.