Friday, February 29, 2008

India Hotspot for Emerging Diseases

From National Public Radio another eye opener on emerging diseases. A team of researchers from the Consortium for Conservation Medicine, the Institute of Zoology (London) , Columbia University and Univ. of Georgia have shown that infectious diseases such as SARS, Ebola, AIDS are on the rise and their emergence likelihood is spatially non-random. Some places are more likely to act as sources of these diseases than others. Being something of a spatial analysis buff and a map freak I found this most revealing:

Source: Nature

a) zoonotic pathogens from wildlife
b) zoonotic pathogens from non-wildlife
c) drug-resistant pathogens
d) vector-borne pathogens

Spin the combinations any way you like and India especially north India emerges as a hotspot for emerging diseases in every which way. Not very surprising considering the very high population density and proximity with domesticated animals. The recent outbreak of Avian Bird flu in West Bengal is a reminder that such threats are real and the assessed risks are not an outcome of some computer simulation done in a far away lab. In this case Indian authorities acted promptly to control the threat and even received a commendation from the UN Food and Agriculture Organization. Yet there are still worrying trends that we have be aware off. Take case d in above figure, the one that indicates risk distribution of vector-borne pathogens. Nearly all of India is a high risk area. It's not just population density that is the problem but the abysmal state of public sanitation and cleanliness in our cities and villages. The Surat plague epidemic some years ago shows that this is a clear and present danger we face. Case a which is risk from pathogens from wildlife also takes a more urgent meaning especially in the light of recent reports of deforestation and dwindling tiger populations. I have written about these issues in earlier posts from a perspective of biodiversity and wildlife protection, but human wildlife interaction is increasing in India due to encroachment into forest by people living at the margins of these forests and by continued logging of dense forests. This is what Kate Jones one of the paper authors had to say:

Emerging disease hotspots are more common in areas rich in wildlife, so protecting these regions from development may have added value in preventing future disease emergence

There is a positive spin to everything. The fact that this research identified India as a hotspot for pathogens from wildlife indicates we still have some wildlife areas left intact! Protecting them will be good for both animals and people.


  1. West Bengal is in East India, no matter which way you look at it.

    FYI North India consists of J&K, HP, Punjab, Haryana, Rajasthan, Uttranchal and UP. Now compare the population density of these areas with rest of India. Unless of course you belong to that school of thought that anything apart from TN,AP,KA and KL is "North India".

  2. For me a southindian, anything apart from TN,AP,KA and KL is "North India". It doesn't matter to us if WB is east of is still NORTH