A pandemic infection is an infection that attacks or affects the population of one or multiple regions, countries or continents. A pandemic infection results in serious illness globally due to the fact that the virus is easily transmitted from person to person.
Some people confuse a pandemic with an epidemic. An epidemic is a seasonal outbreak that is specific to one region or country while a pandemic affects people globally. A new virus strain or a virus that humans have very little or no immunity to is responsible for a pandemic while an epidemic is caused by a virus which is already circulating among people. In general, a pandemic causes more harm and results in a much higher number of deaths, economic loss, and social disruption than an epidemic.
A pandemic infection normally occurs as a result of the influenza A virus making a sudden change which is known as an antigenic shift thus causing new protein combinations on the virus. This results in a new influenza A virus subtype that humans are not familiar with thus making it easy for it to affect them since that they have little or no immunity to it. Some famous pandemics in history include: Black Death in the 1300, the Bubonic Plague of 1855, the Spanish Flue in 1918 – 1920, HIV or AIDS which emerged in the 1980s and is still spreading and the Swine Influenza of 2009.
A pandemic has six stages as defined by the World Health Organization. Stage 1 is where there is an influenza virus circulating among animals but has not caused infections in humans. Stage 2 is where an influenza virus circulating among animals causes infections in humans. Stage 3 is where an animal or human influenza virus has affected a small group of people but has not caused any community-level outbreaks.
Stage 4 is where the virus has resulted in sustainable community level outbreaks. Stage 5 is where the said virus has resulted in community level outbreak in two or more countries in one continent. Stage 6 is where the community level outbreaks occur in one or more countries in another continent. A pandemic is fully matured once it reaches the sixth stage.
