Introduction:

Zoonotic diseases are those that are transmitted from animals to humans and account for over 60% of infectious outbreaks. Deforestation due to expanding agriculture and logging, animal breeding, and livestock farming are creating a conveyor belt for the transmission of microbes, hitherto confined to their primary animal hosts in wild life, to the veterinary population and then to human habitats. Anthropogenic climate change creates conditions for vectors like mosquitoes and ticks to spread to new geographies. They transport the microbes to the human body. Microbial genetics evolve far more rapidly than humans. Microbes which are confined to forest animals or small human communities follow the survival rules of evolution, and generally have low virulence, because the extinction of their host will lead to their own extinction

Body:

Challenges posed by Zoonotic diseases in India:

• Humans now crowd together in large numbers, travel fast and far in many modes of transport, and unknowingly transmit microbes to other humans through sputum, saliva, semen, blood, and other bodily fluids. This enables the virus to multiply rapidly and mutate to more virulent forms.
• Vaccines are presently not available against many of these viruses, though some early success has been reported in candidate vaccines for Ebola and Zika.
• Specific drug treatments too, are unavailable.
• Laboratory diagnosis is possible in specialised labs but is mainly useful for identifying the nature of the outbreak, modelling its likely spread, and alerting the health system of the anticipated clinical severity of the cases that will arise.
• India has one of the highest density of livestock population and poorly guarded animal-human interface makes it vulnerable to disease outbursts.
• The Indian subcontinent has been identified as one of the four global hotspots at increased risks from emergence of new infectious diseases, particularly zoonoses according to various studies.
• Economic risk:
  • The case for control of zoonotic diseases (zoonoses) is compelling. The economic losses from six major outbreaks of highly fatal zoonoses between 1997 and 2009 amounted to at least US$80 billion.
  • The health infrastructure in India, already quite shabby, would bend it’s back in trying to deal with situations like these.

India’s actions:

• India is now expanding its laboratory network but epidemiological surveillance systems need further strengthening.
• In the absence of specific treatments, supportive care has been provided in the case of Nipah virus attack. Fluids for adequate hydration and electrolyte balance; medicines to control fever, and intensive care with respiratory and circulatory support are given when needed.
• During any outbreak, isolation of the patient, avoidance of direct contact while providing care, tracing, examination of all contacts, and limiting their movement during the incubation period are helping to contain the spread.
• Preventive measures include hand washing and avoiding contact with bodily fluids of a person known or suspected to be infected. Avoidance of direct or indirect contact with animals, who act as primary or reservoir hosts, is necessary and people are being made aware.
• Effective risk communication to the public is especially necessary, to enable them to adopt preventive personal protection measures, seek timely medical care, and avoid mass panic. This requires clear and open information sharing by trusted experts who are adept in jargon-free messaging via mass media.
• In Jaipur, India, dog vaccination and sterilization resulted in a decline of human rabies cases to zero.

Way forward:

• A rational response to such outbreaks requires an understanding of why these viruses cross species, how they are transmitted among humans, what preventive measures can be taken, which tests and treatments exist, and whether the health system is ready to contain the outbreak at an early stage.
• Microbes must be vigilantly monitored during outbreaks to study if highly infective viruses are suddenly seized with mutation madness to develop higher virulence, especially in crowded populations where the virus has a free run.
• Given the elevated risk to India from zoonotic diseases, it is important to have a policy framework in place to prevent an outbreak.
• India needs to fund creation of data and evidence-base (data to support actions) on these infections so that they can be controlled in animals.
• India should prevent infections spreading to humans. This can happen with better collaboration (between various agencies), an operational framework from the government, better surveillance and sharing of data on these diseases.
• The effectiveness of zoonotic disease control requires early detection at the source of the disease in animals, an early and accurate diagnosis, and rapid disease control measures. Therefore, One Health, a collaborative approach finds an important place at this human-animal interface to work effectively in disease prevention.
• Numerous examples already exist of the success of this collaboration in One Health like in Chad, joint animal–human vaccination campaigns of DPT and polio in children and CBPP control in livestock resulted in greater coverage in both humans and livestock, and pastoralists became more aware of public health services.
• Reporting by the media should exercise responsible restraint to avoid stoking mass hysteria.
• Virology centres need to be established more
• Border screening has to be done strictly.