Endemic Disease

• 16 May 2020

Why in News

Recently, the World Health Organisation (WHO) predicted that novel coronavirus could become endemic to the world.

• The rapid spread of Covid-19 across the world has been characterised as Pandemic by the WHO.
• Though India has made great efforts in containing the spread of the virus, the probability of its conversion into the category of endemic would be a great vulnerability.

Key Points

• Endemic Disease:
  
  • A disease is called endemic when the presence or usual prevalence of its infectious agent is constant within a given geographical area or population group.
  • When the cases begin to rise, it is classified as an epidemic. If this epidemic has been recorded in several countries and areas, it is called a pandemic.
  • Some examples of endemics include chicken pox and malaria, where there are a predictable number of cases every year in certain parts of the world.
  • According to the WHO, the novel coronavirus may become just another endemic virus in communities, and may never go away.
• R0 and Spread of the Disease:
  
  • The mathematical figure ‘R0’(pronounced “R-naught”) indicates how fast an infection is spreading.
  • It is called the basic reproduction number and indicates the average number of people who will contract the virus from a person who has already been infected, in a population that does not have immunity for the said disease.
  • If R0=1, then the disease is endemic.
  • When R0>1, it implies that the cases are increasing and that the disease will eventually become an epidemic.
• When a Disease Becomes Epidemic
  
  • The Disease becomes “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.
  • 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.
  • Epidemic diseases typically have higher mortality and morbidity than the diseases which have become endemic, owing to lack of clinical experience and knowledge. Over time, effective prevention and treatment interventions emerge for the disease that has become endemic.

Types of Endemic Diseases

• Holoendemic Diseases: This kind of endemic disease affects mostly children. This infection is highly prevalent in the early years of life. The adult population do not show traces of diseases as much as children do. Malaria is a type of holoendemic disease.
• Hyperendemic Diseases: These types of endemic diseases are constantly present at a high rate and are found among all age groups equally. E.g. African Sleeping Sickness and Chicken Pox.

Source:IE