India is highly vulnerable to a range of animal-to-human infections

The Indian government is making an all-out effort to contain the outbreak of swine flu. Already, over 14,500 cases have been reported and some 850 have died. But swine flu, or the H1N1 influenza, is only one among several diseases with zoonotic origin that can spread rapidly. 'Zoonoses' are infections that are transmissible from animals to humans. Incidentally, swine flu, has now moved on from being zoonotic to becoming a seasonal flu that spreads from humans to humans. More worryingly, while India is prone to their occurrence, there is limited information available to effectively combat them. Right now, they have been occurring in small pockets but some have been spreading across the country, and without better facilities to monitor them India would be ill equipped to manage a large outbreak of these diseases.

"Studies have shown that India has one of the highest density of livestock population and this in the backdrop of poorly guarded animal-human interface makes the country highly vulnerable to zoonotic disease outbursts," says Manish Kakkar, Senior Public Health Specialist at the Public Health Foundation of India (PHFI). "Majority of this livestock is in small holdings and in informal settings. 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," he adds.

Indeed, various zoonotic diseases have been occurring in different pockets of the country at regular intervals. Consider, for instance, Leptospirosis. The disease shot into the limelight after the 2005 floods in Mumbai. It is a water-borne bacterial infection spread from the urinary tracts of rodents and cattle. Leptospirosis can damage the liver, cause jaundice and, in some cases, even affect lungs. Its symptom is often fever with jaundice which means it can go undetected initially. The high risk population includes sewer workers and farmers tending to their crops in paddy fields. The disease, first noticed in the Andaman Islands, used to earlier occur in pockets of Gujarat, Maharashtra, Tamil Nadu and Kerala. But now, according to PHFI, there are reports of people with this ailment even in North India. This means it is spreading across the country and there is an urgent need for the government to evolve a strategy to combat it and prevent an outbreak.

Similarly, Brucellosis is another zoonotic disease. It spreads from cattle, sheep and goat, causing fever, infertility and even abortions. The high risk groups are dairy farmers and veterinarians. "The problem here is that there is no national level data available," says Kakkar. "While there are various government agencies we have really no idea of how widespread this is nationally. There are smaller studies that have shown that animal population impacted by this could be 12 to 15 per cent, which is quite high. Among the high risk human population that deal with these animals, five to 15 per cent could be affected, which again is high."

There are host of other infections which are spread from animals. Bovine tuberculosis is spread from cattle. Anthrax is a bacterial infection spread from dead animals, usually cattle, and tends to occur in backward tribal areas, where sometimes sick animals are killed and consumed. Then there is Avian flu which is spread from poultry to humans. "It is a serious disease," says Kakkar, "The mortality levels can be quite high as it could be fatal in almost every second person affected by it." SARS (Severe Acute Respiratory Syndrome) is another disease of zoonotic origin but today spreads human to human and causes respiratory problems.

The most commonly known animal to man disease is, of course, Rabies. It is spread through dog bites and scratches but most Indian towns and cities have made little effort to combat it. "There would be an estimated 30 million street dogs across the country and of these, less than 10 per cent would have been vaccinated and sterilised," says S. Chinny Krishna, Vice Chairman of the Animal Welfare Board of India. The World Health Organization mandates a higher coverage (at least 70 per cent). "It will help if Rabies is made a notifiable disease and if municipal corporations in states are strengthened to better handle waste management," he adds.

Clearly, given the elevated risk to India from zoonotic diseases, it is important that we have a policy framework in place to prevent an outbreak. "We need to fund creation of data and evidence-base (data to support actions) on these infections so that they can be controlled in animals," says Kakkar. "We 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."