
Pandemic is a term used to describe the spread of an infectious disease over a large geographic area that affects a large number of people. Due to the high morbidity and mortality rate, a pandemic can cause significant damage to the economy.
Although the spread of COVID-19 across the globe has highlighted this term recently, COVID-19 is not the first time a pandemic has occurred. Examples of pandemics include:
- Smallpox
- HIV/AIDs
- Plague in Europe in the 14th century
- Influenza pandemic of 1918
- H1N1 or swine flu in 2009
Factors that determine the severity of a pandemic include:
- Transmission rate of the disease-causing organism
- Severity of the illness caused
- Age groups affected
- Immunity of the people infected
Factors that affect disease prognosis and outcome include:
- Age
- Ethnicity
- Gender
- Related medical conditions
- Pregnancy
- Medications
- Poverty and crowding
- Certain occupations
6 stages of a pandemic
According to the World Health Organization, the progression of an infectious disease occurs in six stages:
- Phase I: Disease is limited to animals and humans have not been affected.
- Phase II: Human infection from animals is seen.
- Phase III: Cases of infected individuals are seen here and there.
- Phase IV: Infection starts spreading from one person to another, leading to a community outbreak of the disease (epidemic).
- Phase V: Disease spreads across countries.
- Phase VI: More than one country in every continent gets affected (pandemic).
If the disease occurs frequently in one area but nowhere else, it is called endemic.
What are protective measures to take during a pandemic?
The following measures can help reduce the risk of infection during a pandemic:
- Washing hands frequently
- Wearing masks
- Keeping hands away from the eyes, mouth, and nose
- Maintaining personal hygiene
- Avoiding crowded places
- Maintaining social distance
- Staying away from infected individuals
- Isolating if infected
- Keeping basic medications, food items, and other essentials available
- Avoiding unnecessary travel
- Getting vaccinated if eligible
What is the impact of a pandemic?
Besides taking millions of lives, a pandemic is also associated with extensive economic loss. It can also cause:
- Political instability
- Poor mental health
- Fall in the gross domestic product (GDP), losses in business and jobs

SLIDESHOW
Bacterial Infections 101: Types, Symptoms, and Treatments See SlideshowReady. Pandemics. https://www.ready.gov/pandemic
Madhav N, Oppenheim B, Gallivan M, et al. Pandemics: Risks, Impacts, and Mitigation. In: Jamison DT, Gelband H, Horton S, et al., eds. Disease Control Priorities: Improving Health and Reducing Poverty. 3rd ed. Washington (DC): The International Bank for Reconstruction and Development / The World Bank; 2017 Nov 27. Chapter 17. https://www.ncbi.nlm.nih.gov/books/NBK525302/
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