The problem of Emerging Viral infections
-Dr. Prem Nair, Medical Director, Amrita Institute of Medical Sciences, Kochi, Kerala
Emerging and re-emerging Viral infections are a major problem in South Asia (India, Sri lanka, Bangladesh, Pakistan, Bhutan, Nepal). The main burden of vector-borne infections includes Dengue, Chikungunya, JEV, Influenza, SARS, Nipah, Hantavirus and Chandipura viruses.
Many factors contribute to the emergence of these viral infections such as urbanization, environmental degradation, global warming, extensive deforestation and afforestation, rapid transport, building dams or canals, migration of people/vectors, genetic mutations, rearing of livestock or birds, etc.
There are about 1500 pathogens known to infect humans and 300,000 viruses that infect mammals, some of which can jump from animals to humans and cause disease. The Indian subcontinent is a hotspot of zoonotic, drug resistant, vector-borne pathogens. Their transmission requires contact, the probability increasing with contact. With 1.34 billion people, over 500 million livestock and 800 million poultry, the rates of human-animal, animal-animal and human-human contacts are high. These increase the potential for emergence, re-emergence and sustenance of new pathogens. Deforestation brings wildlife in direct contact with domesticated animals and humans, alters weather patterns and eventually zoonosis.
There should be increasing public awareness of proper garbage disposal, avoidance of water stagnation, environmental degradation, vector control measures, recognition of early signs and symptoms with notification to public health authorities and appropriate treatment.
In the intermediate and long term, a comprehensive strategy needs to be evolved. A national Virus Surveillance system to study the epidemiology of viral disease, development of diagnostic facilities, a central serum bank and a virus repository and capability to rapidly develop and test vaccines is mandatory. An international network of databases of virus infections, together with a global network for diagnosis and containment of virus infections needs to be instituted. Infections originating in South Asia are a global threat and India, aspiring to be a world leader, must not ignore its responsibility towards global health and disease proliferation.