A girl shares the entrance to her house with a family of chickens in Oyo State, Nigeria (photo credit: ILRI/Mann).

Researchers at the International Livestock Research Institute (ILRI) argue in an opinion piece published yesterday on the Guardian‘s Poverty Matters Blog (11 February 2011) that the best way to reduce the threat of infectious diseases sweeping the world is to watch for their rise in animal populations. A remarkable 61% of all human pathogens, and 75% of new human pathogens, such as those causing bird flu and HIV/AIDS, are ‘zoonotic,’ that is, transmissible between people and animals.

‘Some of the most lethal bugs affecting humans originate in our domesticated animals,’ says Delia Grace, a veterinary and food safety scientist at ILRI. But, she warns, ‘there’s a dangerous disconnect between the agricultural and health sectors of most countries, with the former focused on increasing the production and profitability of crop and livestock farming, with little regard to their effects on human health, while the medical community focuses on ailments of people, disregarding the spread of diseases through livestock populations, which can then “jump” to human communities.’

‘We ought to be viewing animals as sentinels of infections threatening our public health,’ Grace says, ‘rather than waiting for people to start dying before we start acting to control the spread of a zoonotic disease.’

Grace and another veterinary scientist, ILRI deputy director for research John McDermott, say that this is particularly true in developing countries, where ‘the capacity of veterinary services to track and control outbreaks is lagging dangerously behind livestock intensification’.

They cite Indonesia as a ‘classic example of a “hotspot”, where development and rapid change surpassing the speed of the industrial revolution threaten animal and human health in ways we have never seen before’.

Much of Africa, they say, contains ‘coldspots’—’areas locked in a timewarp of underdevelopment and crippled by old diseases’ easily contained elsewhere.

Ironically, some of the countries most worried about new disease threats, including the United States, Japan and the European Union, ‘have well-established, reasonably well-regulated livestock industries that can usually get new diseases under control. In these wealthy countries, consumer outrage over the occasional appearance of tainted foods is often greater than the disease risk that those foods pose to consumers.’

‘How diseases are managed in these three different regions—hot, cold and worried,’ say Grace and McDermott, ‘should differ.’

Read ILRI’s opinion piece published in the Guardian‘s Poverty Matters Blog: Animal farming and human health are intricately linked, 11 February 2011.

Read more on ILRI’s views on this topic in this week’s Economist.