Vultures and Voltaren

When I lived in India in the 80’s, one of the commonest sights encountered daily were congregations of vultures. Said to be the most abundant raptor species on the planet, the White-backed Vulture, and the Long-billed Indicus Vulture were more common than pigeons in South Asia and then numbered an estimated 10 million.

A most unlovely bird, with its crooked neck and bald, wrinkled head, the various species of native vulture nevertheless played an important role in ancient myth, religious practice, and practical hygiene. Vultures were sacred birds to Hindus because they rescued King Rama’s wife, Sita, from captivity. The Parsee community of Bombay, which followed ancient Zoroastrian practices forbidding burial and cremation, left their dead to be consumed by flocks of vultures living in the surrounds of their famous “Towers of Silence”. Vultures played an essential ecological role in the Asian setting, cleaning up dead and diseased livestock before they could putrefy in the heat and transmit diseases to other animals and human beings.

Then in the late 1990’s, something serious happened to the Indian vulture population. It crashed and it crashed spectacularly all over the sub-continent. In 2003, researchers from Washington State University reported high mortality rates of up to 86% in nesting populations being studied in Pakistan. This alarming data matched comparable findings from nesting sites in India where declines in adult bird numbers as high as 95% were being recorded. What was happening? Was some mystery virus at work?

Painstaking post mortem work on dead birds failed to point to a virus or microbe as the factor behind the mystery deaths. Many post mortems instead showed high crystalline uric acid deposits characteristic of visceral gout, and clear evidence of renal failure.

Vultures with gout? The imagination boggles--- but this seemed to be incontestably the case, following further exhaustive toxicology tests of dead birds.

Eventually, suspicions settled on the new and widespread use in India of diclofenac as a veterinary cure-all for lameness, fever and general well being among Indian livestock. Subsequent experimentation showed that birds fed on buffalo and goat meat from diclofenac treated animals resulted in renal failure and death.

Diclofenac is one of a class of drugs called Non Steroidal anti-inflammatory Drugs (NSAIDS) and includes such familiar products as Ibuprofen. It is commonly marketed for human use as Voltaren. Interestingly, the US Food and Drug Administration turned down a request to use the drug to treat lameness in horses in 2003.

Following extensive study of vulture mortality both within India and abroad, in early 2005, the Prime Minister of India endorsed a recommendation to ban the drug for veterinarian use. Hopefully once sufficient time has passed to eliminate the drug from treated Indian livestock, vulture numbers in the sub-continent will begin a slow recovery.

Now obviously, the physiologies of birds and upper mammals are very different and I certainly do not intend to frighten anyone away from using Ibuprofen or Voltaren simply because Indian vultures are dying off. But I do think the vulture story adds a necessary note of caution for all of us who have arthritis and who find ourselves obliged to resort to regular NSAID ingestion. We must remember that no drug is without toxicity and that all drugs, whether prescription or not, have to be approached in full awareness of that plain fact, after a careful balancing of potential benefits and potential risks.

And let me tell you too, those Indian vultures always struck me as very hardy creatures indeed, with gastric systems far tougher than my own! I’ll think of them next time I reach casually for an NSAID.