So-called “half-masking,” or wearing a face mask below the nose, may allow coronavirus the opportunity to enter your body, according to a recent study and health experts. During the coronavirus pandemic, half-masking still leaves you at risk for contracting Sars-CoV-2, the virus that causes COVID-19, physicians told Fox News.

“It’s like wearing your pants with only one leg in,” Dr. Frederick Davis, associate chair of emergency medicine at Northwell Health/Long Island Jewish Hospital in New York, told Fox News. “A mask, or other face covering, should cover both your mouth and nose.”

A study out of the University of North Carolina (UNC) published in the journal Cell suggested the novel coronavirus tends to first penetrate and infect the nasal cavity and in some cases can be aspirated into the lungs, where it can progress to pneumonia, according to a study news release.

The team of researchers at UNC used reporter cells to track the Sars-CoV-2 virus and mapped where it infiltrated the respiratory tract. They noted the novel coronavirus infected the nasal passages the most and decreased infiltration as it progressed down the respiratory path to the throat and lungs, according to the study.

The published report also revealed that the virus targeted ACE2 (angiotensin-converting enzyme-2) cell receptors as its means of entry to the body. The ACE2 receptors are more abundant in the nasal-lining tissue and less prevalent in the lower portions of the respiratory tract, according to the report.

One of the co-authors of the study told Fox News this could explain why the nasal portion of the upper respiratory tract was more susceptible to COVID-19 infection and why wearing a mask is ultimately important.

“Unfortunately, SARS-CoV-2 has learned how to evade normal nasal host defense mechanisms and uses this receptor to infect the nasal lining cells,” co-senior author of the study, Dr. Richard Boucher, director of the Marsico Lung Institute at the UNC School of Medicine, told Fox News. “Nasal cells, unfortunately again, are endowed with the ability to produce literally millions of viruses when infected.”

“Viruses produced in the nose can be then distributed to the olfactory tissues in the roof of the nose, producing loss of smell, to the mouth, infecting salivary glands and producing symptoms of dry mouth, and to the lung where they produce pneumonia with shortness of breath and indeed death. So a mask must protect the nose to be effective in preventing the acquisition and spread of COVID19,” Boucher explained.

Dr. Fred Davis, who was not part of the study, also remarked on the importance of covering the nose and mouth with a mask.

“Any face covering is not as effective if only one’s mouth is covered since many viruses are transmitted by respiratory particles that both come from and enter the body through one’s nose and mouth,” Davis told Fox News.

The emergency department physician said half-masking is ineffective.

“Having a face covering only covering your mouth and not your nose does not utilize the covering to its full potential to reduce your risk of spreading or contracting the disease,” Davis said. “It’s important to wear a mask when you are in contact with others, and when you do, to wear it properly.”