ROME — The coronavirus continues to spread rapidly in Italy despite a near-total lockdown on residents’ movements and interaction.

Data as of Sunday evening revealed 20,603 people currently testing positive for the disease, a significant 24-hour jump of 2,853 new cases.

Italy’s coronavirus death toll rose to 1,809 deaths, an increase of 368 over Saturday’s figure. On the positive side, Italy also reported that the number of those who have tested positive and then recovered from the disease is now 2,335, representing a similar increase of 369 cases.

Although the mortality rate of the coronavirus in Italy seems quite high — 1,809 deaths out of 24,747 registered cases (7.3 percent) — this figure is grossly misleading.

As the World Health Organization (WHO) reported recently, for the coronavirus, “data to date suggest that 80% of infections are mild or asymptomatic.” This suggests that the vast majority of those infected with the virus are unaware of it and therefore undiagnosed. Current attempts to calculate the mortality rate in Italy (and elsewhere) based on the number of known cases are, therefore, fraught with complications.

According to reports, as of Sunday, the total number of those tested for the disease in Italy is only 124,899 out of a population of just over 60 million, or just 0.2 percent of the population. Those being tested are not randomly selected, but overwhelmingly present symptoms of the infection.

Using WHO’s estimate as a guide, it is possible that Italy’s actual number of cases of coronavirus is closer to 125,000 than the 25,000 currently being reported. This would also mean that the fatality rate could be closer to 1.4 percent than the 7.3 percent suggested by reported data.

Given that Italy has the second oldest population in the world, only exceeded by Japan, the percentage of deaths from the virus is probably abnormally high in Italy as well, as the coronavirus overwhelmingly targets the elderly and especially elderly males. The current average age of those who have died of the virus in Italy stands at about 80 years of age.

Given the coronavirus’s long incubation period, the success of Italy’s current efforts at containment should only become evident in the coming days. Recent new cases are likely the result of contagion that occurred prior to the general quarantine of the population.

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