WHO defines Disease Outbreaks as, "occurrence of cases of disease in excess of what would normally be expected in a defined community, geographical area or season. An outbreak may occur in a restricted geographical area, or may extend over several countries. It may last for a few days or weeks or for several years"(Disease Outbreaks, World Health Organization). Further, Disease outbreaks are usually caused by an infection transmitted through person-to-person contact, animal-to-person contact, from the environment or other media or from exposure to chemicals or radioactive materials. The environment constantly backs health of an individual where he/she lives in, conditions around, prevalence of diseases and other risks factors associated with it. India having the second largest population in the world, dense tropical livestock that succumbs to the transmission of diseases between man and animals more strongly (Sekar N, Shah N, Abbas S, kakkar M, 2011). It is evident that India from time immemorial has been a witness for many diseases to occur within its territory like plague, malaria, cholera, dengue etc. New diseases like Nipah and Zika are coming to India. The battle with these diseases is not an easy one. Furthermore, there is an emergence of rare diseases in India, with already 450 kinds of rare diseases recorded in India poses a huge public health challenge (National Policy, rare diseases, 2017). Further, the growing challenges of Morbidity from Antimicrobial resistance (AMR) is yet another issue emerging in India. Antimicrobial resistance in India equally poses a threat to the health system. The rampant use of antibiotics results in formation of super bugs that are resilient to all types of drugs. Unnecessary prescription and over the counter drugs are of the main reasons behind their excessive overuse. It is estimated that 56 524 neonates die due to resistance - neonatal sepsis caused by bacteria resistant to first line of antibiotics in India (Laxinarayan R, Bhutta Zulfikar, 2016). Drug resistance like multi drug resistance in case of tuberculosis, malaria resistant to ACT therapy etc. (Dikid T, Sharma A et al, 2013).
This document thus becomes very important in understanding the prevalence of various health risks, diseases outbreak and other rare/orphan diseases in India over the years. A strong prevention mechanism, early warnings system, research, strong surveillance structure is needed to combat the huge challenge of disease outbreaks. There are also social, behavioral and environmental factors, which affect the level of disease outbreaks (Heymann D, 2005).