The 21st century is often referred to as a century of viruses. Since its beginning, the world has seen the emergence of several viruses, including severe acute respiratory syndrome coronavirus (SARS- CoV), Influenza A/H1N1 (pandemic flu), Ebola and Zika, causing public health threat of international concern. Currently, we are facing a pandemic threat from the 2019-novel coronavirus that originated in China and spreading globally.
Communicable or contagious infectious diseases can transmit from one infected individual to others in a variety of ways. The 2019-nCoV is primarily transmitted from an infected person to close contact through droplets and fomites. However, more data is required to understand the transmission dynamics fully.
This is not the first time the world is dealing with contagious diseases. In the past, we have had plague and influenza pandemics, including the 1918 Spanish flu which wiped out 20-50 million victims, but spread at a slow pace from continent to continent. However, today’s world is a global village with seven billion people well connected. The 2019-nCoV that emerged in China in December 2019 reached several countries by mid-January and has severely affected the economy. For enabling a globally coordinated response, the World Health Organization has declared this outbreak a public health threat of international concern.
Though India mysteriously escaped the 2002-03 SARS-CoV from China and MERS-CoV from the Middle East, it experienced the 2009 pandemic flu (Influenza A /H1N1) and Zika. In 2018, we had a deadly but limited outbreak of the Nipah virus, which took the lives of 18 people, including a healthcare worker in Kerala. Influenza viruses account for nearly 20 per cent of annual fever-related hospitalisation and cause a significant mortality. Most of these emerging viruses are zoonotic -- the transmission occurs from animals to humans. Fruit-eating bats appear to be harbouring several viruses, including SARS-CoV, MERS-COV, Ebola, and Nipah. Live animal markets, hunting of wild animals and habitat loss due to deforestation have increased the human-animal interphase conducive for transmission to humans.
Is our public health system prepared to handle these threats? India’s investment in healthcare is mainly focused on curative services. Though immunisation and specific disease control/elimination programmes are working substantially well, our real-time laboratory-supported disease surveillance and disease containment systems are inadequate. They function exceptionally well in firefighting mode, often compromising with other services. India needs substantial investment in public health services in terms of infrastructure, trained workforce and a strategic vision. The public healthcare system should be inclusive. Sustainable models of public-private partnerships should be built to enhance the public health response.
We should be prepared to expect the unexpected in public health. Availability of a rapid diagnostic service across India, along with proper clinical and infection prevention and control practices in hospitals, including dedicated well-maintained isolation facilities at designated hospitals, is a must for controlling the outbreaks like 2019-nCoV.
Innovative data collection, processing and analysis platforms and disease prediction modelling can significantly augment the public health response or even avert a calamity. Another area we should focus on is to encourage interdisciplinary research to complement public health. India has the capacity and, if put together strategically, can develop diagnostic kits, vaccines and therapeutics like any developed country.
Influenza vaccines are available, but annual vaccination is not suitable for most of the countries due to enormous expenditure. However, researchers are working on developing next-generation influenza vaccines that can provide long term generic protections. At least seven candidate vaccines are under development for coronaviruses. Several groups have started working on the 2019-nCoV vaccine and the WHO research and development blueprint is coordinating the work.
However, at least a year is required to take any of these vaccines to people. China has already started clinical trials of available antivirals among 2019-nCoV infected cases.
The best way to contain the 2019-nCoV outbreak in India is the strict home quarantine of people returning from virus-affected areas for 14 days and isolating the symptomatic cases. Any lapse will allow the virus into the community as during the incubation period, the person can be infectious.
Preparedness of the public health system is the key to curb any repeated outbreaks of contagious diseases and limit their impact on global health and economic security.
Prof Arunkumar Govindakarnavar
Director, Manipal Institute of Virology, Manipal Academy of Higher Education (Deemed to be University)