Table 2 summarizes the health impact of four past pandemics in the 1918–2018 period: Spanish flu, February 1918 to April 1920; severely acute respiratory syndrome (SARS), November 2002 to July 2003; swine flu, January 2009 to August 2010; and Middle East respiratory syndrome (MERS), April 2012 to present. These four pandemics could be put into two groups according to the type of virus that them: the Spanish flu and swine flu were caused by an influenza virus, while SARS and MERS were caused by a coronavirus.7
Health consequences of selected pandemics
| Number of cases . | Number of deaths . | ||||
|---|---|---|---|---|---|
| Disease . | Period . | Global . | USA . | Global . | USA . |
| Respiratory pandemic caused by influenza virus | |||||
| Spanish flu (H1N1) | February 1918 to April 1920 | 1/3 of global population | na | 50 million | 675,000 |
| Swine flu (H1N1/09) | January 2009 to August 2010 | 0.7 billion to 1.4 billion | 60.8 million | 284,000 | 12,649 |
| Respiratory pandemic caused by coronavirus | |||||
| Severely acute respiratory syndrome (SARS-CoV) | November 2002 to July 2003 | 8,439 | 73 | 812 (WHO) | 0 |
| 774 (CDC) | 0 | ||||
| Middle East respiratory syndrome (MERS-CoV) | April 2012 to present (December 2020) | 2,566 | 2 | 882 (up to December 2020) | 0 |
| COVID-19 (SARS-CoV-2) | November 2019 to present (26-2-2021) | 118.8 million | 29.3 million | 2.5 million | 0.5 million |
| (2nd and 3rd highest are India and Brazil at 11.3 million each) | |||||
| Number of cases . | Number of deaths . | ||||
|---|---|---|---|---|---|
| Disease . | Period . | Global . | USA . | Global . | USA . |
| Respiratory pandemic caused by influenza virus | |||||
| Spanish flu (H1N1) | February 1918 to April 1920 | 1/3 of global population | na | 50 million | 675,000 |
| Swine flu (H1N1/09) | January 2009 to August 2010 | 0.7 billion to 1.4 billion | 60.8 million | 284,000 | 12,649 |
| Respiratory pandemic caused by coronavirus | |||||
| Severely acute respiratory syndrome (SARS-CoV) | November 2002 to July 2003 | 8,439 | 73 | 812 (WHO) | 0 |
| 774 (CDC) | 0 | ||||
| Middle East respiratory syndrome (MERS-CoV) | April 2012 to present (December 2020) | 2,566 | 2 | 882 (up to December 2020) | 0 |
| COVID-19 (SARS-CoV-2) | November 2019 to present (26-2-2021) | 118.8 million | 29.3 million | 2.5 million | 0.5 million |
| (2nd and 3rd highest are India and Brazil at 11.3 million each) | |||||
Sources: Center for Disease Control, CDC (2019a and 2019b), Johns Hopkins University (2021), World Health Organization, WHO (2020 and 2021).