Covid-19 immunity can help guide pandemic management

Recent scientific work shows that people who have been infected with SARS-CoV-2 have acquired immunity which lasts for at least nine months.

In other words, for a relatively long period of time, we can’t become ill with COVID-19 twice. This important and most welcome news will have significant consequences.

According to official statistics on November 27:

– 61.36 million people worldwide have been infected with the coronavirus, of which

– 17.48 million (28.49%) are still visibly ill

– 1.44 million (2.35%) have died

– 42.44 million (69.16%) are cured definitively, or at least for a reasonably long period.

The worldwide recovery total includes the following national figures:

– India: 8,718,517

– US: 7,849,718

– Brazil: 5,528,599

– Russia: 1,712,174

– Germany: 676,100

– Italy: 661,180

– Poland: 494,869

– Canada: 280,923

– Switzerland: 218,900

– France: 158,236

– Japan: 116,378

– Belgium: 36,912

The above figures underestimate the real totals considerably. Since the start of the pandemic, the number of people cured is calculated using only diagnosed cases. But cases for which there have been positive tests are only a part of the real number of cases.

Millions of people have been in contact with coronavirus without being tested or even without realising it. Most of them have recovered, or will recover, without having been counted in any way. Figures for France are particularly understated because of a strict method of counting cases but insufficient follow-up due to lack of testing capacity.