The latest outbreak of coronavirus is taking its toll worldwide: with more than 900 deaths and more than 24 000 known cases, the world is in the grip of fear.
The median age of coronavirus-related deaths is 75, while, in the case of the latest outbreaks, it’s between the ages of 49 and 56 years, according to the Journal of the American Medical Association.
And while at least two newborns have been infected, it seems that children are not succumbing to the virus in a big way. But why exactly is that?
"We don't fully understand the phenomenon – it may be because of differences in the immune responses of children compared to adults," Dr Andrew Pavia, the chief of the Division of Pediatric Infectious Diseases at the University of Utah stated in the publication Live Science.
"One hypothesis is that the innate immune response, that is the early response that is aimed broadly at groups of pathogens, tends to be more active, in children," he said.
"My strong, educated guess is that younger people are getting infected, but they get the relatively milder disease," stated Dr Malik Peiris, chief of virology at the University of Hong Kong in the Straits Times.
The exception to the rule
In one case, a 10-year old travelled to Wuhan, China with his family. When they returned to Shenzhen, the entire family, ranging from ages 36 to 66, displayed symptoms like a sore throat, fever, diarrhoea and pneumonia.
The child, however, had signs of viral pneumonia in his lungs, but otherwise displayed no symptoms.
In the cases of previous coronavirus outbreaks such as severe acute respiratory syndrome (SARS) and Middle Eastern respiratory syndrome (MERS), the pattern was similar – no children died during the outbreak and deaths tended to occur within the age group 45 and older.
Children under the age of 12 displayed minimal symptoms and were much less likely to be admitted to hospital, according to news reports.
Immune system and age
Experts are baffled but agree that adults may be more susceptible because of their age. As we age, our immune systems also deteriorate. And with a weakened immune system comes chronic diseases – higher blood pressure, heart disease, diabetes – making it more difficult to fight off infections.
Respiratory system and age
While children and adult are equally exposed to the coronavirus, a likely explanation may be that children have healthier and stronger respiratory systems than their older counterparts, who have had years of smoke and pollution exposure that might have weakened their respiratory systems.
According to Dr James Cherry, a professor in paediatrics and infectious diseases at UCLA’s Geffen School of Medicine, adults are more likely to suffer from an immune response that causes acute respiratory distress syndrome. When the immune cells do not function as they should, it can cause an inflammatory response in the lungs, leading to fluid filling the air sacs in the lungs, according to Annals of Translational Medicine. This reaction is fatal, with a 40% death rate – which is in fact the main cause of death in people with coronavirus, according to Dr Cherry.
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