Context

As per the World Health Organization (WHO), like HIV, the novel coronavirus could become endemic and “may never go away”, and urged for a “massive effort” to contain the spread of COVID-19

About

• A disease is endemic when its presence or usual prevalence in the population is constant.
  • Epidemic: When the cases begin to rise, it is classified as an epidemic.
  • Pandemic: If this epidemic has been recorded in several countries and areas, it is called a pandemic.
• Some examples of endemics include the chicken pox and malaria, where there are predictable number of cases every year in certain parts of the world.
• A 1948 definition of endemic cholera cited in the Indian Journal of Endocrinology and Metabolism defines it as:

“An endemic area is one in which over a number of years, there is a practically continuous presence of clinical cholera with annual seasonal exacerbation of incidence.”

• The dictionary of epidemiology defines an endemic disease as,

“the constant presence of a disease or infectious agent within a given geographic area or population group; may also refer to the usual prevalence of a given disease within such an area or group.”

When does a disease become endemic?

• RO=1: If R0, which is the rate at which the virus is transmitted is equal to 1, then the disease is endemic.
• R0>1: When R0>1, it implies that the cases are increasing and that the disease will eventually become an epidemic.
• R0<1: If R0<1, it implies the number of cases of the disease are decreasing.

Here, R0 refers to the number of people infected by a person who has the disease.

Why is it a risk? 

• When epidemics become endemic, they become “increasingly tolerated” and the responsibility of protecting against it shifts from the government to the individual.
• This means, rather than government agencies actively engaging in tracking and identifying cases, the individuals themselves will be responsible for managing risk from the disease and seeking care.
• Further, the sociopolitical response to the disease may also change, with investment in the disease becoming institutionalised along with the disease-inducing behavioural changes in people.
• Once people become aware of the risks of infection, they will alter their behaviour and mitigate the consequences.
• Epidemic diseases typically have higher mortality and morbidity than endemic diseases, owing to lack of clinical experience and knowledge, as well as innate pathogenicity.
• Over time, effective prevention and treatment interventions emerge.