Throughout history, there have been several pandemics, including the 2009 H1N1 virus, the 1918 Spanish flu, and most recently COVID-19. In each occurrence, these pandemics have been linked to similar features, causes, and severe effects. As a result, based on the past, it can aid in determining what exactly defines a pandemic. The characteristics of global spread and little or no population immunity, as well as effects such as high mortality rates, can all define a pandemic.
A pandemic can be characterized as a disease that is prevalent globally. A global spread is considered to be inevitable as the entire world is susceptible when a pandemic emerges. For example, the COVID-19 virus is no exception as it spans six continents. According to Worldometer, the COVID-19 pandemic has spread across 220 countries and territories. On the European continent, the pandemic has been recorded across 48 countries/territories, while in Asia - 49. In addition, the pandemic has also been reported in 39 and 14 countries/territories in North and South America respectively. Furthermore, there have been reported cases across 58 countries/territories in Africa and 12 on the continent of Oceania. This emphasizes that a pandemic is not limited to a particular place or country; it is prevalent across the world.
Another distinguishing feature of a pandemic is minimal or no population immunity. When a pandemic emerges anyone, is at risk of contracting the disease. In fact, according to Worldometer, there have been 158.3 million reported cases of COVID-19 worldwide to date. Moreover, there are reports of people getting infected with COVID-19 for a second time (WHO, 2020). However, vaccines have been developed and administered to fight off the illnesses associated with the coronavirus. But this still does not protect against transmission, therefore, wearing masks and physically distancing are necessary. Another example is the 1918 influenza pandemic, known as the 'Spanish flu', which infected about 500 million people, or one-third of the world’s population (CDC, 2019). Thus, a pandemic can be defined by its low or non-existent level of population immunity as they affect millions of people.
Finally, a pandemic is a disease that results in high mortality rates. As defined by CDC, (n.d, par.1), “A mortality rate is a measure of the frequency of occurrence of death in a define population during a specified interval”. For example, COVID-19, which is primarily caused by SARS-CoV-2, can result in death based on its level of severity. In fact, the COVID-19 virus continues to circulate at very high rates and has claimed the lives of 3.2 million people worldwide, with 5786,000 recorded in the USA (Elflein, 2021). Furthermore, the 1918 Spanish flu was very severe. As a result, 50 million deaths were estimated worldwide, with about 675,000 occurring in the United States (CDC, 2019). Furthermore, according to CDC (2019), the 2009 H1N1 virus killed approximately 151,700 – 575,400 people globally during the first year. This highlights that pandemics are associated with high mortality rates and can be defined based on it.
In a nutshell, a pandemic is defined by its global spread as it continues to spread across six continents. Notably, COVID-19 and Spanish flu recorded a whopping 158.3 million and 500 million infection rates respectively, thereby supporting the claim of minimal to no population immunity. Furthermore, pandemics result in high death rates, with the COVID-19, Spanish flu, and the 2009 H1N1 virus killing millions of people worldwide. Therefore, a pandemic can be defined based on the characteristics of global spread and the minimal or no population immunity, plus the effects of high mortality rates.