Accueil > Pour les médias > Communiqués de presse
The Working Group of the Office International des Epizooties has just submitted its annual report on wildlife diseases reported throughout the world over the past 18 months.
Some of the major diseases to have emerged during this period include:
Diseases transmissible to humans
Bovine tuberculosis is a particularly serious problem in the Kruger National Park in South Africa, where the geographical spread of the disease has been reported in buffaloes, with the incidental spread to other animal species living in the parks, including kudu, baboons, lions, cheetah and leopards.
In Uganda, the tuberculosis reported in the Queen Elizabeth National Park since the late sixties has just been confirmed in buffaloes in the Kadepo Valley National Park.
In Zambia, tuberculosis has been identified for several years in Red Lechwe on the Kafue flats. Transmission of the infection to herds of wildebeest was confirmed for the first time in 1998.
In Europe, tuberculosis was reported in Spain (fallow deer, red deer, wild boar and lynx), and in the United Kingdom (in badgers, roe deer, fallow deer and red deer).
In the United States of America, the outbreak of tuberculosis that had struck white-tailed deer in the state of Michigan continues to pose problems as it has been found that the disease has been transmitted to coyotes, red foxes, racoons, black bears and bobcat. Attempts are under way to combat the disease in cervids by reducing the density of their populations and by prohibiting the feeding of deer by humans.
In Hawaii, the search is on for a sylvatic reservoir of tuberculosis following detection of the disease in a cow; wild pigs seem to be the most likely source of the infection.
In Canada, bovine tuberculosis is endemic in a sub-population of bison, and a case has just been reported in an elk.
Brucellosis is still endemic in several wild animal populations in Africa, the main species affected being buffalo, hippopotamus and waterbuck.
In Europe, the agent of the disease was identified in wild boar in France and Italy, as well as in brown hare in Austria, France, the Czech Republic and Switzerland. The recent spread of the infection amongst free-roaming domestic pigs seems to indicate that a wild reservoir is the source of the pathogenic agent. Brucellosis was also reported in chamois and red deer in the Alps.
In Canada, the pathogenic agent was isolated in American bison, reindeer and caribou, as well as in aquatic mammals, including beluga whale, narwhal and ringed seal.
In the United States of America, the disease was diagnosed in elk in the state of Idaho. In this region, elk have been fed by humans for several years, and this situation substantially increases the risk of transmission of the pathogenic agent.
Epizootic rabies in foxes continues to recede in Western Europe following immunisation campaigns involving the distribution of bait containing vaccines against the disease. Other forms of rabies, in particular the infection in insect-eating bats, persists with no perceptible change. In early 1999, an Egyptian fruit-eating bat was found to be infected with a strain of rabies of African origin in the south of France. These bats (fruit bats) are not present in Europe, but they have been sold as pets for several years. The sick animal was imported into Belgium directly from Africa, in January 1999, then sold to a pet shop in Bordeaux (France) in March 1999. One hundred and twenty-two people had to be given preventive treatment against rabies. The sale of Egyptian fruit bats and other chiroptera, which is legal in the European Union, will certainly need to be reviewed very rapidly given the health risks associated with bats from tropical countries.
Rabies in terrestrial animals is enzootic in several parts of North America. Oral vaccination programmes against the disease are being carried out in four states in the United States of America and in one province in Canada.
In Namibia, 76 cases of anthrax were reported in wild animals, most of them in the Etosha National Park where the disease in enzootic. Eleven wild species were affected, including elephant, zebra, wildebeest and springbok.
The West Nile virus belongs to a group of viruses transmitted by arthropods, hence their name "arthropod-borne" or "arbovirus". First discovered more than 60 years ago in Uganda, the West Nile virus was later identified in various African, Eurasian and Middle Eastern countries. In humans, the disease generally shows flu-like symptoms such as fever, headaches, muscular aches, sore throat and rash. Mortality in humans varies between 3 and 15% and is higher in elderly people.
The West Nile virus was isolated in more than 40 species of mosquitoes and certain ticks. In nature, the viral cycles include apparently healthy birds and mosquitoes, with birds considered to be the vertebrate hosts that act as a reservoir for the pathogenic agent. The problem currently facing the state of New York is different from previous episodes, because in this case the wild birds perish from the infection. American crows were the worst affected, but it also struck fish crows, blue jays, laughing gulls, American robins, rock doves, mallards, sandhill cranes, black-crowned night-herons, and several species of birds in captivity in the Bronx zoo.
Serious diseases affecting only animals
Several major diseases that can affect both wild and domestic animals have been reported to the Working Group:
Classical swine fever which remains a very significant problem in European wild boar. In 1998, outbreaks were reported by Germany, France, Italy, the Czech Republic and Switzerland. The classical swine fever virus, which was isolated in Tessin (Switzerland), was identical to the one previously found in wild boar in the Varese region of Italy.
The virus can be transmitted from wild boar to domestic pigs both directly (where contact is possible) and indirectly (via contaminated feed). In Germany and Italy, the epidemiological data suggest that there is cross transmission of the virus between domestic pigs and wild boar. When domestic pigs and wild boar live well apart, human activity could be the cause of transmission of the disease from wild swine to domestic pigs, and vice versa.
The prevalence of this endemic situation seems to have increased in Europe over recent years.
Surveillance was less intensive in the eastern United States of America because no abnormal deaths had been reported in this region. Since surveillance began in late 1997, laboratory examinations have not identified any cases of the disease.
Further information concerning wildlife health