Climate change raises risk of emerging viruses, infectious diseases in India

Changes in climatic conditions, particularly temperature and humidity changes following events such as extreme rainfall in one place and drought in another, undulation In the spread of vector-borne and infectious diseases across India, according to scientists.

It may be too early to attribute climate change to the recent rise in respiratory viral infections, such as H2N3, adenovirus and swine flu, in many parts of India. Scientists say no. But definitely plausible.

The prospect of climate change leading to an increased burden from the spread of diseases such as dengue, chikungunya and malaria is looming large.

According to public health expert Poornima Prabhakaran, steadily rising temperatures affect the transmission patterns of pathogens such as viruses and vectors through different pathways.

“These include changes in incubation period, contagious potential and duration of contagion, all of which can influence disease trends,” said the Public Health Foundation of India (PHFI) Environment Prabhakaran, director of the sanitation center, said. PTI.

The incubation period is the time between exposure to the pathogen and the first appearance of symptoms or signs.

Prabhakaran noted that changing climatic conditions will also favor the spread of viruses and their vectors and the potential for disease transmission.

“Hot and humid conditions can affect both disease transmission routes, disease frequency and disease severity,” she explained.

Ecologist Avi T. Banak said climate change could also lead to changes in species habitats, which could introduce new vectors in some areas and transmit some species to humans. He added that it could make people more susceptible to some new viruses.

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“For example, extreme rainfall and flooding in drier parts of the country can lead to disease outbreaks typically associated with wetter areas,” said Vanak, Interim Director, Center for Policy Design, Ashoka Trust for Research in Ecology and the Environment (ATREE), Bangalore, said PTI.

“This is applicable to both water-borne diseases such as cholera and dysentery, and vector-borne diseases such as malaria, dengue and chikungunya,” he explained.

Extreme weather events such as heat waves can also put animals under great stress, making them vulnerable to disease spread and zoonotic outbreaks, he said.

Prabhakaran’s team is working on a collaborative study aimed at demonstrating links between changing climatic conditions and patterns of vector-borne diseases such as dengue fever and malaria.

The CHARISMa project aims to build a climate health information services dashboard to assist city-level officials in decision-making for timely and effective hotspot-focused interventions.

what is the way out?

Modeling future scenarios using state-of-the-art techniques that enable prediction of future disease patterns and hotspots is a useful tool to help decision makers plan appropriate and timely interventions. Researchers say it could be a tool.

A study published last year in the journal Nature predicted that climate change would greatly increase the risk of new viruses infecting humans.

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It concluded that there are currently at least 10,000 viruses “quietly circulating” among wild mammals, and that climate change could trigger them to infect humans. This is especially true for countries such as Indonesia, China, the Philippines, and some parts of Africa, which have been hotspots for deadly diseases spreading from animals to humans over the past decades, including influenza, SARS, HIV, Ebola, and COVID. increase. -19, said the researcher.

Global warming is associated with the risk of emerging viruses, Postdoctoral Fellow, Infectious Diseases and Vectors – Unit on Ecology, Genetics, Evolution and Control (MIVEGEC) Institute for Development (IRD), Montpellier, France Researcher Debapriyo Chakraborty agreed.

“In India, part of the Global South, it is believed that certain vector-borne viral diseases such as dengue fever are on the rise with global warming,” said Chakraborty. PTI.

“These viruses are now speculated to be spreading to new places such as mountains that were cold for mosquitoes to breed decades ago,” he added.

Chakraborty said global warming could also lead to increased flooding, leading to important water-borne viral diseases such as hepatitis A and norovirus, a highly contagious virus that causes vomiting and diarrhea. I believe there is

“Global warming is also projected to increase the spread of emerging viruses by causing an increase in the movement of environmental refugees. These are some of the risk factors,” he said.

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There are several perspective research papers on the risks between climate change and disease risk in India. However, much of the primary literature, including solid scientific research, still comes from the Arctic.

Chakraborty said climate change could lead to an increase in respiratory virus cases in India, but scientific research is needed to establish a clear link.

“For example, we know that the traditional emergence of bird flu viruses during the winter has been associated with winter migratory ducks. It is speculated that the warmer months also cause eclosion,” he said.

Many respiratory viruses originate in wildlife, and climate change may affect the emergence of new viruses by altering wildlife ecology and behavior.

“Also, changes in human behavior and demographics in response to climate change (e.g., increased use of air conditioners, changes in crop cycles, large-scale migration) could alter viral epidemiology,” said Chakraborty. rice field.

There is another concern that climate change brings. The increased frequency of spread of otherwise rare diseases to new regions and the potential for the emergence of new hotspots for certain pre-existing diseases such as typhus and leptospirosis.

“Also, there can be large inter-annual variations in the emergence of such diseases, and consequently the need for infrastructure and training for such outcomes varies greatly spatially and temporally from year to year. more likely to do so, making precautions and preparation difficult,” he added.