Infectious diseases can spread at an alarming pace, resulting in enormous losses of human lives as well as large costs to the society.¹ The 21st century has witnessed a wave of infectious diseases outbreaks having a devastating impact on the lives and livelihoods globally.² An article by Mukherjee S has shown that atleast 30 new infectious diseases have emerged over the last 3 decades posing a grave threat to millions of people worldwide.³ Glaring examples include SARS-CoVoutbreak in 2003, swine flu pandemic in 2009, MERS-CoVoutbreak in 2012, Ebola outbreak in West Africa in 2013-16, and zika virus epidemic in 2015 which have resulted in substantial mortality and morbidity.² They have spread their tentacles across borders to infect multiple countries.² 

Numerous studies and reports have shown that approximately 60% of all human infectious diseases recognized so far, and approximately 75° /o of the emerging infectious diseases (EID) that have affected the human race over the past 30 years were zoonotic in nature.³ 

The major challenge to combat these infections is that there are no specific approved vaccines or treatment for many of them as well as limited scope to prevent or control them.³ Factors contributing include urbanization and destruction of natural habitats, climate change and changing ecosystems, changes in population of reservoir hosts or intermediate insect vectors and genetic mutation within the microbes, international trade and commerce, changes in human demographics and behavior, lack of public health services and infrastructure, and antibiotic resistance.³ 

References: 

1. Barac A, Poljak M, Ong DSY. Editorial: Innovative Approaches in Diagnosis of Emerging/Re-emerging Infectious Diseases. Front Microbial. 2020;11:619498. Published 2020 Dec 3. doi:10.3389/fmicb.2020.619498.
2. Baker RE, Mahmud AS, Miller IF, et al. Infectious disease in an era of global change. Nat Rev Microbial. 2022;20(4):193-205. doi:10.1038/s41579-021-00639-z.
3. Mukherjee S. Emerging Infectious Diseases: Epidemiological Perspective. Indian J Dermatol. 2017;62(5):459-467. doi:10.4103/ijdijD_379_17.