One Health – an integrated approach to health.

Beyond the well acknowledged problems of rising temperatures and catastrophic weather occurrences, climate change, an obvious reality of our day, has far-reaching effects. While it is understandable that worries about human public health dominate the conversation, it is important to realise that the effects of climate change are much more complicated and intertwined. Numerous intricate processes influence changes in the lifecycles of vectors, reservoirs, and pathogens inflicting diseases in domestic and wild animals and plants. This also holds true to the disruption of synchrony between interacting species and the alteration or destruction of ecosystems.

This complex problem incorporates social dynamics, economic inequality, veterinary medicine, environmental deterioration, and changes in the landscape, necessitating an all- encompassing strategy that goes beyond conventional bounds. The "One Health" approach, apotent idea that emphasises the connection of human, animal, and environmental health, is the strategy forward. According to WHO, “One Health is an approach to designing and implementing programmes, policies, legislation and research in which multiple sectors communicate and work together to achieve better public health outcomes.”

To give an example, one crucial strategy for a one health approach to Public health is World Health Organization’s WASH (water, sanitation, and hygiene). Animal and human excreta management must be coordinated because they can both contribute to environmental contamination and the spread of antibiotic resistance. Climate change can lead to more frequent periods of high precipitation and as a result of excess in runoff and associated wash- off of human and animal waste from open defecation or manure-fertilized fields, zoonotic pathogens can contaminate surface and drinking water sources, resulting in disease outbreaks.

The WASH strategy helps nations create national standards, formulate regulations, and set up efficient surveillance systems. Similarly, a rise in leptospirosis cases has been linked to an increase in extreme occurrences, such as hurricanes and flooding, for instance, which calls for a close examination of the animal reservoirs. Such ecosystem approaches to health framework would provide a more thorough and larger context to address the impact of climate change on health because it acknowledges the eternal relationship between people, animals, and their environment.

As Keralites are becoming all the more aware with recurrent Nipah infections, the One Health approach is critical to addressing health threats in the animal-human-environment interface. Fruit bats of the Pteropodidae family are the natural host of Nipah Virus (NiV) and they are being increasingly recognized as reservoir hosts for viruses that can cross species barriers to infect humans and other domestic animals. The infected bats shed the NiV in their secretions and excretions. However, bats that are reservoirs of NiV, remain asymptomatic.

The One Health approach uses the existing surveillance systems of various stakeholders to detect early warning signals of impending outbreaks for timely and effective public health responses. It also facilitates sharing of pertinent information among stakeholders for taking necessary action.

These recurrent outbreaks have taught us that the district, block and panchayat-level administrations, as well as elected people's representatives, should be involved in discussionsnot only during outbreaks but also prior to any occurrence, to highlight the possibility of an outbreak from endemic- and epidemic-prone diseases. In order to improve coordination and cooperation at the community level, regular intersectoral meetings, presided over by district or sub-district administrators, should be convened for sharing of information and to explore potential prevention measures.

Further research on the transmission dynamics and ecological drivers of these viruses in reservoir hosts and spillover events, with special consideration to the influence of seasonal changes, will help us develop evidence that will enable monitoring systems be more aware and readier for a prompt coordinated public health response.