What is a pandemic?


  • The World Health Organization (WHO) declared the COVID-19 outbreak a pandemic.

What is a pandemic?

  • Simply put, a pandemic is a measure of the spread of a disease. When a new disease spreads over a vast geographical area covering several countries and continents, and most people do not have immunity against it, the outbreak is termed a pandemic. It implies a higher level of concern than an epidemic, which the US Centers of Disease and Control Prevention (CDC) defines as the spread of a disease in a localised area or country.
  • There is no fixed number of cases or deaths that determine when an outbreak becomes a pandemic. The Ebola virus, which killed thousands in West Africa, is an epidemic as it is yet to mark its presence on other continents. Other outbreaks caused by coronaviruses such as MERS (2012) and SARS (2002), which spread to 27 and 26 countries respectively, were not labelled pandemics because they were eventually contained.

Which outbreaks have been declared pandemics in the past?

  • A major example is the Spanish flu outbreak of 1918, which killed between 20-50 million. Cholera pandemics have been declared multiple times between 1817 and 1975. In 1968, an pandemic was declared for H3N2 that caused about a million deaths. The last pandemic declared by the WHO was in 2009, for H1N1.

Why has WHO declared a pandemic for COVID-19?

  • China announced the outbreak on December 31 and declared a public health emergency on January 30. The WHO waited for 72 days before declaring it a pandemic. The outbreak was so far mostly limited to China, which has taken stringent countermeasures.
  • In the last two weeks, cases outside China increased thirteen-fold and countries infected have tripled. Italy, for instance, had 888 cases on February 29 which rose to 4,636 in a week. “We expect to see number of affected countries, number of cases and number of deaths go higher in coming days,” WHO director general Tedros Adhanom said.

Does the declaration change the approach to the disease?

  • “Describing the situation as pandemic does not change WHO’s assessment of the death risk posed by the virus, it does not change what WHO is doing, and it doesn’t change what countries do,” WHO said.
  • There is a view among many experts, however, that the categorisation as a pandemic can lead to more government attention. “The categorisation by WHO indicates the risk of disease for countries to take preventive measures. It will help improve funding by international organisations to combat coronavirus. In India, we are already doing all that is possible and more government funding is not needed at this point.” said Dr Balram Bhargava, director of Indian Council of Medical Research.