It is a misnomer to think COVID-19 kills only the older populations as people of all ages are susceptible to SARS-CoV-2 infection like any other respiratory infections like influenza. As people age, their immune system response is lowered and they have more chances of conditions like diabetes, hypertension, cancer, cardiac disease, which increases risk of death, say public health experts as the pandemic rages on with no signs of let-up.
“Some people age faster (biological age) compared to their actual chronological age due to frailty. Frail people or those with co-morbidities have higher risk of severe disease and death. Therefore, a significant proportion of COVID-19 deaths are in the elderly. Irrespective of age, the transmission of COVID-19, severity and risk of death depends upon how much of the virus the person is exposed to,” explains Public Health Foundation of India’s (PHFI) Indian Institute of Public Health (IIPH)-Hyderabad Director G.V.R Murthy.
The infectious dose required to transmit SARS-CoV-2 is low because people have never been exposed to it before.
So, children and younger adults — more active and mobile compared to adults have a high chance of contacting adequate infectious dose of SARS-CoV-2 either at play, school or work.
Dr. Murthy says for most of the younger population the immune system responds rapidly to fight the virus invasion and successfully blocks more severe disease. However, underlying unknown or undetected health conditions may be present among the younger people, which increase the risk of death, he warns.
Exposure to a high infectious dose can lead to a higher viral load which also increases severity. It only means all age groups are susceptible to COVID-19 infection, but most youths show milder infections so recover faster compared to the elderly where even with a lower infectious dose, a more severe infection is observed. More severe the infection and the lower the person’s immunity, greater is the risk of death.
Behaviour a factor
People’s attitudes and behaviour contribute significantly to the increased transmission and doubling rates of infected persons. Recent evidence which has looked at doubling times in nine countries including India shows that the doubling time is significantly affected by preventive measures taken and large gatherings also impacts the doubling time adversely.
Since health, social and economic development go hand-in-hand and one affects the other, ‘empathetic development’ is the way forward. “We have seen opening the metro has not lead to a sudden spike in cases because steps have been taken to enforce people to behave properly. Study after study has reiterated face masks should be considered a useful low-cost device along with social distancing and hand hygiene,” says IIPH State chief, who had worked with World Health Organisation (WHO) and was UNAIDS Consultant with National AIDS Control Organisation (NACO).
Mask measure
Masks should now become a ‘fashion statement’ since studies reveal early termination of social distancing measures could trigger a devastating second wave. Yet, if greater than 70% of population uses ‘safe’ masks properly, it can lead to cessation of transmission, he insists.
This data should be effectively used to educate people and change their behaviour and for governments to mandate safe measures and strictly enforce them. ‘Safe’ mask is one that’s worn properly, cleaned (if reusable) and used as long as people are outside their homes or in offices and disposed off in a closed bin/ bag.
Lockdowns reducing physical contact between individuals outside the house have a limited role as most transmission is within the confines of a house, adds Dr. Murthy.