On Tuesday, the World Health Organization (WHO) said the spread of the coronavirus disease around the world is driven by younger people, those in their 20s, 30s, and 40s, many of whom are not just asymptomatic but also unaware that they are infected. “The epidemic is changing,” Takeshi Kasai, the organisation’s regional director for the Western Pacific said in an online briefing, Reuters reported.

WHO’s statement comes at a time when Covid-19 cases around the world appear to be plateauing, perhaps for the first time since April. That was the last time the seven-day average of new cases reported around the world stayed at the same level. It was a long plateau too – it was only in the third week of May that cases started perceptibly rising again, and they continued to till the last week of July. For the past fortnight, though, they have stayed pretty much at the same level (in the 250,000s). All the seven-day averages are from the New York Times database. HT’s Covid-19 data specialist Jamie Mullick wrote about this in an article titled “Coronavirus: Has the third curve flattening begun?” on August 12.

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Kasai was also quoted as saying that WHO believes the Asia-Pacific has “entered a new phase of the pandemic”. That isn’t evident in the numbers yet.

The fact that a large number of the infected are now young has been in evidence for some time. As HT reported in an article on August 11, the virus “disproportionately infects younger people, while it severely affects those who are older”. Based on data till July 31 (by which time India had registered 1.7 million cases), as many as 62% of those infected were below the age of 45 years. A break-up of the 26-44 years age group wasn’t available, but 40% of the people infected by the Sars-CoV-2 virus that causes Covid-19 belonged to it; 22% of those infected were younger than 25 years. There’s more according to the unreleased data from the ministry of health and family welfare that was accessed by HT: 26% of those infected were in the 45-60 age group, which means that it is mathematically possible, and quite probable, that 70% of all Covid-19 positive people in India are below the age of 50 years. Only 12% were over the age of 60.

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This could explain the higher recovery rates not just in India, but elsewhere in the world too – progressive case fatality rates have declined with every passing month of the pandemic’s run. According to the health ministry data cited above, the proportions are completely inverted when it came to deaths: 50% of those who died from the disease in India were over the age of 60, and another 37% between the ages of 45 and 60 years. Only 13% were below the age of 44 years.

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Kasai’s comments and the data reflect contrasting behaviours of the old and the young. Early in the pandemic’s run, data established the vulnerability of older people, and many of them responded by opting for self-isolation and taking adequate precautions. They continued to do so even after the first wave of lockdowns. In contrast, young people ventured out soon after the restrictions on movements and activities were eased. This column has previously referred to the second wave in both Spain and France and highlighted how this was being driven largely by young people originally infected by what can only be described as summer fever – and who then went on to be infected by something that was more dangerous, if not to them, then to older members of their families.