NEARLY 20 months since Sars-CoV-2, the virus that causes coronavirus disease (Covid-19), was first reported in China on Dec. 31, 2019, there still seems to be no end in sight to the pandemic it has caused and the restrictions imposed to curb its spread.
Over 214 million people worldwide have been infected, of whom 4.47 million have died, as of Aug. 27, 2021, for a case fatality rate of 2.08 percent, according to the World Health Organization (WHO).
Yet infections are accelerating, courtesy of more highly transmissible virus strains, like the Delta variant now detected in 132 countries.
The Severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2), now in 200 countries and territories, continues to threaten lives, jobs, health care systems and economies.
When will this pandemic end?
A look at past pandemics may provide a hint on how the current pandemic could play out.
There have been four influenza pandemics since the 20th century—in 1918, 1957, 1968 and 2009—says the WHO.
While Covid-19 and influenza (flu) are caused by different viruses—Covid-19 is caused by infection with a coronavirus, and flu by infection with influenza viruses—both are contagious respiratory diseases, said the United States Centers for Disease Control and Prevention (CDC).
Despite its fearsome reputation, the 2002-2003 outbreak of the first identified strain of the Severe acute respiratory syndrome coronavirus (Sars-CoV-1) was not classified as a pandemic. It infected just 8,437 people worldwide, killing 10 percent of them.
A pandemic occurs when an epidemic has spread over several countries or continents, affecting large numbers of people, said the CDC.