Coronavirus statistics, food for thought

The Coronavirus cases in Europe have moved the focus away from China, but the news coming from there is interesting: outside Hubei province, the Covid-19 epidemic is in a downward phase. The study by a scientific journal confirms the mortality rate (about 2% of those infected), which increases with age and the presence of chronic diseases, and is more lethal for males (2.8% vs 1.7% of females) and smokers.

World 29_02_2020 Italiano

The unreasonable fear that has been generated in recent days by the cases of pneumonia from the new Coronavirus (Covid-19) has completely diverted attention from what is happening in China, now outclassed in media attention by local cases.

Yet the news coming from China is extremely interesting and worthy of reflection. These are the figures: the confirmed cases of Coronavirus have reached 77,658.

The deaths during the last week were 71 - the lowest figure for over two weeks - for a total of 2,663 deaths. The mortality rate is therefore 2.8%.

But there is another very important figure to note: outside Hubei province - the epicentre of the epidemic, where over 90% of Chinese cases occurred - there were only nine new cases in the rest of China.

What does all this mean? That the epidemic has entered a downward phase. It may be thanks to the quarantine measures, or to the weather that is getting milder, in any case the surge of the virus that made the world tremble seems to be declining. At least where the contagion started.

But back to the figures. In recent days, on February 17, a scientific journal, the Chinese Journal of Epidemiology, released an important epidemiological study on the mortality rate from Covid-19. The study examined 72,314 patients, including 44,672 confirmed cases of Coronavirus. The report confirms the mortality rate highlighted so far, i.e. a 2% death rate among those infected.

However, it is the analysis by age group that provides us with the most interesting data. First of all, among children from 0 to 9 years of age, the rate is zero percent: no children of that age died. The mortality rate increases with age: it goes from 0.2% in the 10-39 age group, i.e., including children, young people and young adults, to 1% of those in their fifties, 3.6% of those in their sixties, 8% for people between 70 and 80 years of age, and finally it peaks at 14.8% for those aged 80 years and over.

What do these figures tell us? That Covid-19 is a respiratory virus able to cause serious problems to elderly and frail people, like many other strains of pneumonia and bronchitis, for instance those produced by Pneumococcus - which in Italy alone causes about 8,000 deaths every year - mainly in elderly people. It may seem strange, but, again in Italy, an analysis of hospital discharge records shows an increasing trend in recent years in the incidence of pneumococcal pneumonia in the period 2001-2010 with an average hospitalisation rate of 9.8/100.000 in the paediatric population and 16.5/100,000 in subjects over 65 years of age: 200,000 cases of pneumonia of viral and bacterial origin, therefore transmissible, which, however, have never led to attacks on pharmacies and supermarkets on a quest for masks, or to a curfew.

In addition, the presence of serious chronic diseases such as diabetes, hypertension, cancer, chronic respiratory failure and cardiovascular problems are fertile ground for the Coronavirus. Especially in adults aged 70 and over, with a compromised immune system. This is the identical evidence emerging from Italian cases in the present days.

Other interesting data coming from the Chinese epidemiological study are those concerning the characteristics of the affected people: the virus is more lethal for men than for women: 2.8% vs 1.7%. The researches highlighted that one of the factors that make the Coronavirus more dangerous is smoking: about one third of worldwide smokers live in China, of which 50% are men and only 2% women.

This is another finding that should be obvious: smokers damage the cells in their lungs, therefore obviously more cases are found among smokers. Perhaps smokers should reflect on this finding and instead of wearing a mask or sprinkling themselves with household bleach, they should ditch their packets of cigarettes.

Finally, the analysis of Chinese researchers shows that 80.9% of Coronavirus infections can be classified as “mild”, 13.8% as “serious” and only 4.7% as “critical”. If then, as some speculate, the number of people who have contracted the Coronavirus is much higher than reported so far, this would mean an even lower mortality rate.

In short, although alarmism is still extremely high, this study is a source of great optimism.