In Brief


Sumatra has a declining tiger population of around 500, under threat from all sides and increasingly vulnerable to disease outbreak as their population fragments. Reports from human-tiger conflict cases suggest wild tigers are behaving strangely, apparently losing their fear of people and straying into villages - symptoms worryingly consistent with infection with potentially deadly Canine Distemper Virus (CDV).

No relevant veterinary testing has yet been conducted in Sumatra but there are parallels with recent tiger behaviour in the Russian Far East in which CDV infection has been firmly established. Anecdotal evidence suggests the problem may be widespread in Sumatra and potentially in other tiger countries.


WVI’s overall objective is to develop a network of vets and field staff dealing with tigers across their range state, that are able to deal with tigers in a conflict situation and to assess and mitigate any diseases that are affecting the health and behaviour of wild tigers.

Through this network of people working with tigers, we (as a community) aim to determine the following:
- The presence and distribution of Canine Distemper Virus and other significant diseases through sampling both tigers and domestic animals.
- The level of infection lethal and the effect it is having on the tiger populations (both as a pathogen and in that it is likely to change the tiger’s behaviour, increasing the probability of it being killed by man)
- Where the reservoir is (domestic dogs most likely) and how the tigers are coming in to contact with them.

The future, following data analysis, is to develop mitigation strategies to reduce the impact of diseases on tiger populations.

These objectives are appropriate to Sumatra, the Russian Far East (to both the Amur tiger and leopard), and possibly Bangladesh. Other range states have not yet been investigated to any depth.


WVI will enable and supplement resources within the tiger country (Indonesia in the first instance) with its expert support, where necessary. It will provide training to cover everything from safely immobilising/reviving tigers to ensuring efficient sample testing and maximising opportunities for disease surveillance.

Data will be collected and analysed both in-country and internationally for both a local and international overview. A network of vets and field staff working with conflict and non-conflict tigers will enable the in-country tiger community - including the Indonesian Veterinary Medical Association and The Wildlife and Conservation Office (BKSDA) - to provide greater self-support and learn from others’ experiences in different range states.

With a clearer picture established, ways can be found to stop the transmission of disease to the tigers.

Big cats fall prey to dog disease

Indonesia could lead the world in tiger-saving research

Some of the world’s rarest big cats are facing a new and deadly threat – from a dog disease.

Canine distemper virus (CDV) is one of an emerging range of pathogens threatening tigers worldwide, confirms British charity Wildlife Vets International.

Now an Indonesian initiative to help save its dwindling Sumatran tiger population promises a conservation milestone - the world’s first comprehensive tiger disease surveillance programme.

A successful programme could become a lifeline model for tiger range states everywhere, believes Dr John Lewis, a big cat veterinary expert and co-founder and director of WVI.

Following talks earlier this year with Indonesian officials and vets, he is returning to Sumatra in September to advise and help launch a programme to shed new light on the causes and impact of canine distemper and other diseases.

With challenges on every side for Sumatra’s embattled and dwindling tiger population, struggling to survive amidst growing economic and habitat pressures, disease could be catastrophic, says Dr Lewis.

A worrying symptom of canine distemper, that tigers seem to lose their fear of man, increases the chance of human-tiger conflict and leaves them easy prey for poachers.

“We have reports from Sumatra and other tiger range states that tigers are behaving abnormally and we need to know why” he said.  Infection with canine distemper virus could explain at least some cases,

“A tiger disease surveillance programme has never been tackled. If we get it right, it could help us forestall a major problem which is the last thing tigers need in their precarious state.

“We need to find out how these cats are catching distemper, identify how and where they come into contact with domestic dogs which are the most likely virus source, and determine how best to tackle the problem. Otherwise we could lose even more of our vulnerable big cats,” says Dr Lewis.

The Sumatra initiative is a major leap forward in WVI’s work with international tiger conservation alliances from the far east of Russia to the mangrove swamps of the Bangladesh Sundarbans.

Dr Lewis has been involved in the Russian Far East since 2004, and has been invited by Wildlife Conservation Society (WCS) Russia and the Russian Institute of Biology & Soil to work with Russian wildlife vets and Martin Gilbert from Glasgow University on how to combat CDV.

At least three Amur (Siberian) tigers, the world’s largest big cat, have died in recent years after contracting canine distemper. Studies of both the Endangered Amur tiger and the Critically Endangered Amur leopard, with just 40 left in the wild, confirm that many more have been exposed to the virus.

Russia already has examples of abnormal behaviour, where tigers have walked into villages apparently unfazed by their surroundings.

In one incident a gaunt tigress, looking for dogs as an easy meal, was shot by police after several capture attempts failed. In a similar event, an otherwise healthy looking wild tigress was immobilized but later died in captivity. Evidence of CDV were found in both.

Other examples of tigers entering villages or stalling traffic on major roadways, behaviour possibly indicative of distemper, have emerged in the last ten years.

In 1994 CDV wiped out a third of Africa’s Serengeti lion population after an outbreak in feral dogs. Lion numbers only recovered when conservationists embarked on a massive dog inoculation programme.

Editor’s Notes:

Russia’s first-ever symposium on wildlife diseases discussed the threat in 2011.

“With all the threats facing Siberian tigers from poaching and habitat loss, relatively little research has been done on diseases that may afflict tigers,” said Dale Miquelle, WCS Russia Director of Programs.

“There are no records of tigers entering villages and behaving so abnormally before 2000, so this appears to be a new development and new threat. Understanding whether disease is a major source of mortality for Siberian tigers is crucial for future conservation efforts.”

Anatoly Astafiev, Director of Sikhote-Alin Reserve, said, “We have seen a fall in tiger numbers within our reserve, so it is very important to know whether at least one of the causes is a recognizable disease, something we may be able to address and potentially prevent.”

Distemper is found worldwide in domestic dogs and has caused infection and death in wild species such as lynx and bobcats in Canada, Baikal seals in Russia, lions in the Serengeti ecosystem in Africa, and raccoons and the endangered black footed ferret in the United States.