COVID-19: Scientists explain why children are less affected, cite difference in lungs

Differences in lung physiology and immune function in children may be the reason why they are more often spared from the COVID-19 than adults, research, which sheds more light on the biological process behind the deadly infectious disease, revealed. Meanwhile, the deadly pandemic has now spread to infect more than 1,22,32,745 people in 188 countries.

A team of scientists, which also consisted of researchers from The University of Texas Health Science Center at Houston (UTHealth) revealed that children under 18 years of age make up 22 per cent of the US population, but added that only about 1.7 per cent of the first 1,49,082 COVID-19 cases in the country belonged to this age group.

Citing the reason behind the same, they said that a molecule in humans called the Angiotensin-converting enzyme 2, or ACE2, which act as doors that allow the novel coronavirus, SARS-CoV-2, into cells, are lesser in number in children's lungs than in adults.  In addition to lesser ACE2, the researchers said that the immune system in children acts differently as compared to the adults, leaving lesser chances of the infection to spread in pediatric patients.

"ACE2 are important for viral entry and there seems to be less of them in children because they increase with age," said Matthew Harting, a co-author of the study from UTHealth.

Most prevalent symptoms

In another research, scientists asserted that persistent cough and fever were confirmed as the most prevalent symptoms associated with Covid-19. Health experts studied a sample of over 25,000 cases of the adults above the age of 16 years with laboratory tests confirmed COVID-19 respiratory disease. A random-effects model for pooling of binomial data was applied to estimate the prevalence of symptoms, subgrouping estimates by country. 

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The researchers – from five universities including the University of Leeds – observed data of COVID-19 patients from over 9 countries and combined the studies from over 851 unique citations, 148 separate studies including the UK, China, and the US. Of that, researchers listed the most common symptoms and the possible outcomes if one contracts the coronavirus. 

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We acknowledge that there is both within-country and between-country differences in the estimated prevalence of different symptoms. We confirm that fever and cough remain the most prevalent symptoms of adults infected by SARS-CoV-2—authors wrote in the study.

Read: Coronavirus: Researchers Say Persistent Cough And Fever Are 'most Prevalent' Symptoms

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