With most studies and efforts focused on patients with coronavirus, not much is known about those who are asymptomatic. In general, scientists have determined that asymptomatic people may just be 'silent spreaders' without symptoms, but recently, they've discovered traces of the virus in their lungs.
Around 40% of those infected with coronavirus remains asymptomatic, lacking symptoms such as fever, fatigue, a severe cough, nausea, and impaired senses. A large percentage of people are unaware that their lungs are actually affected.
Dr. Eric Topol of the Scripps Translational Research Institute and Daniel Oran discovered medical evidence in a series of heart and lung X-rays. The computed tomography (CT) scan of asymptomatic patients had 'ground-glass opacities' or cloudy white areas in the lungs.
Lung Damage
In four separate studies with asymptomatic people, around 50% had ground-glass opacities in their lungs. The same opacities were found in the lungs of patients with severe coronavirus symptoms.
One study including over 3,500 passengers on the Diamond Princess cruise ship showed that 331 out of 712 people that tested positive for Covid-19 were asymptomatic. 76 asymptomatic passengers had their lungs examined and more than 50% of them had lungs with ground glass opacities.
Dr. Aileen Marty from Florida International University explained that the cloudy areas are signs of inflammation in the lungs. She's seen the same signs in her patients, around 67% of which didn't show symptoms but had alterations in their lung CT scans.
Their lungs became ill even without symptoms. Experts have yet to determine if the ground glass opacities are temporary or permanent. They also don't know if the infection will cause pulmonary fibrosis or scarred tissue.
'I think that if you're young and you have enough lung reserve, you're not going to miss it because you're still able to function perfectly fine," Marty said. She compares it to having long hair trimmed, that two inches cut off is not a noticeable difference 'because you have so much hair.'
The same ground-glass opacities were also found in asymptomatic children from Wuhan, China. The signs of inflammation are consistent with the inflammatory symptoms common in children with severe coronavirus.
Dr. Alina Alonso of the Palm Beach County Health Department had been hesitant about schools reopening for this reason. What if the lung damage in children could lead to chronic pulmonary problems, she said, 'we don't know how that is going to manifest a year from now or 2 years from now.'
Read Also: Asymptomatic and Presymptomatic People Cause the Most Coronavirus Infections
Possible Heart Damage
Dr. Valentina Puntmann from University Hospital Frankfurt, Germany, looked for signs of heart damage in asymptomatic people. They found high levels of troponin, a protein that the heart muscle releases when there's damage, another sign of inflammation.
However, more research needs to be conducted since normal hearts can sometimes have elevated troponin levels as well, explained Topol. 'Who knows what other organs are being affected? We don't know,' Topol said, 'No one's ever looked.'
