Mount Sinai Researchers: Why COVID-19 May Be Less Common in Children Than Adults
Findings Published in JAMA Could Lead to Potential Biomarker of Susceptibility
The virus that causes COVID-19 uses a receptor known as ACE2, found on the surface of certain cells in the human body, to enter its victims. Now, Mount Sinai researchers have found that children have lower levels of ACE2 gene expression than adults, which may explain children’s lower risk of COVID-19 infection and mortality. Gene expression is a measure of how much a gene is transcribed. These results, published in JAMA on Wednesday, May 20, may point to a potential biomarker of susceptibility to the virus, known as SARS-CoV-2.
“ACE2 expression may be linked to our susceptibility to COVID-19,” says lead author Supinda Bunyavanich, MD, MPH, Professor of Genetics and Genomic Sciences and Pediatrics, Icahn School of Medicine at Mount Sinai. “ACE2, which stands for angiotensin converting enzyme 2, is a receptor that some might be familiar with because of its role in blood pressure regulation. The coronavirus uses ACE2 to enter the human body, where it spreads. ACE2 is known to be present in our airway, kidneys, heart, and gut. In our study, we took this knowledge a step further, finding that there are low levels of ACE2 expression in the nasal passages of younger children, and this ACE2 level increases with age into adulthood. This might explain why children have been largely spared in the pandemic.”
The research focused on ACE2 due to its significance in COVID-19 infection. The nasal passages are usually the first point of contact for SARS-CoV-2 and the human body. Dr. Bunyavanich’s study is one of only a few examining the relationship between ACE2 in the airway and age.
The retrospective analysis, led by Dr. Bunyavanich, examined nasal passages epithelium from Mount Sinai Health System patients aged 4 to 60. The researchers found ACE2 gene expression in nasal epithelium was age-dependent, lowest in younger children and increasing with age into adulthood.
About the Mount Sinai Health System
Mount Sinai Health System is one of the largest academic medical systems in the New York metro area, with more than 43,000 employees working across eight hospitals, over 400 outpatient practices, nearly 300 labs, a school of nursing, and a leading school of medicine and graduate education. Mount Sinai advances health for all people, everywhere, by taking on the most complex health care challenges of our time — discovering and applying new scientific learning and knowledge; developing safer, more effective treatments; educating the next generation of medical leaders and innovators; and supporting local communities by delivering high-quality care to all who need it.
Through the integration of its hospitals, labs, and schools, Mount Sinai offers comprehensive health care solutions from birth through geriatrics, leveraging innovative approaches such as artificial intelligence and informatics while keeping patients’ medical and emotional needs at the center of all treatment. The Health System includes approximately 7,300 primary and specialty care physicians; 13 joint-venture outpatient surgery centers throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and more than 30 affiliated community health centers. We are consistently ranked by U.S. News & World Report's Best Hospitals, receiving high "Honor Roll" status, and are highly ranked: No. 1 in Geriatrics and top 20 in Cardiology/Heart Surgery, Diabetes/Endocrinology, Gastroenterology/GI Surgery, Neurology/Neurosurgery, Orthopedics, Pulmonology/Lung Surgery, Rehabilitation, and Urology. New York Eye and Ear Infirmary of Mount Sinai is ranked No. 12 in Ophthalmology. U.S. News & World Report’s “Best Children’s Hospitals” ranks Mount Sinai Kravis Children's Hospital among the country’s best in several pediatric specialties.