Climatology at the Service of Veterinary and Human Medicine
Tunis, Tunisia (ots/PRNewswire)
- 6th Merial Symposium on Parasitosis & Arthropod-Borne Diseases: A Bio- Mathematical Model for the Risk Evaluation of Flea & Tick Population
The 6th Merial Symposium on Parasitosis and Arthropod-Borne Diseases opens today in Tunis gathering over 120 climatology, parasitology and veterinary specialists to discuss the impact of global warming on parasitosis(1) and vector-borne diseases(2). This year researchers from North Africa are participating for the first time in focussing on exotic diseases emerging in Europe. The outcome of this year's meeting will be better risk management and the launch of a new climatic biomathematical model called "FleaTickRisk".
For 7 years now, Merial, a joint venture of Merck & Co., Inc. and sanofi-aventis and one of the leading animal health companies in the world, has organized an annual meeting to monitor and discuss diseases both caused by parasites and transmitted by parasites, called the "Merial European Parasitology - Arthropod-Borne Diseases Symposium". The first Symposium was held in Amsterdam in 2001 and the most recent edition was held in Marseille in 2007.
The past few years have seen the emergence of new diseases, or re-emergence of existing ones, sometimes with changes in their epidemiology. In its previous symposia, Merial has reviewed these epidemiological changes (changes in geographical distribution, prevalence, and pathogenicity of vector-borne diseases) and their possible causes.
Today, the theme is much broader as most of these diseases affect both man and animals (zoonoses) and incidence is increasing due to climatic changes, so their management requires a multidisciplinary approach. During last year's symposium, speakers presented results and hypotheses of studies in both veterinary medicine and human medicine conducted in over 25 countries. This year in Tunis, climatologists and socio-economists have joined their veterinary and human medicine counterparts to exchange on this vast topic, but also to discuss common points and differences and set up collaboration programmes between institutes, universities, etc in various countries of Europe and North Africa.
Ticks, Tick Borne Diseases and Modelling: http://www.fleatickrisk.com/
Over the last 10 years, the number of ticks and tick-borne diseases has considerably increased, causing a sudden soar in those human diseases transmitted by forest ticks, such as rickettsiosis, anaplasmosis, and encephalitis; it thus appeared really important to develop epidemiological models linking three key elements:
- biomathematics - to study the dynamics of vectors and pathogens,
- satellite mapping - to monitor the emergence and distribution of diseases related to vegetation & human activities, and
- climatic modelling - to follow parasite activity caused by meteorological trends.
For the first time ever, a new model, called "FleaTickRisk" has been designed in collaboration between climatologists (from Climpact, a start-up between researchers from the CNRS and Paris VI University), biomathematicians (from the research unit of the Lyon Veterinary School associated with the CNRS) and parasitologists (from Merial and the Maisons-Alfort Veterinary School).
After one year of intense development, "FleaTickRisk" can now predict, on a weekly basis, the activity of 3 tick species as well as that of cat fleas in France (pilot country for one year). It can also predict the density of parasites and the risk of disease transmission (ie: animal and human infestations); it has been made available for French Veterinarians on a dedicated website: http://www.fleatickrisk.com/.
This model will be extended to all of Europe in the autumn of 2008 and made available to Veterinarians.
A scientific validation based on parasite collection has started and will continue throughout 2008. The model means that the impact of the climate on parasite burdens can be studied, but it will also help Veterinarians in their day-to-day activity of recommending suitable parasite treatment and prevention.
Impact of global warming
The most recent Parasitology Symposia organised by Merial (Zagreb 2006 and Marseille 2007) confirmed the tendency that certain vector-borne diseases are increasing in Europe, that pathogens are circulating more easily, that the conditions for such changes involve primarily human factors, but that global warming also has a direct impact on arthropod vectors (density, geographical distribution, vectorial capacity).
Within the last ten years, "new" diseases have been reported in horses and carnivores, e.g. babesiosis in Germany, the Netherlands and Belgium, canine monocytic ehrlichiosis in Southern Europe, A. platys anaplasmosis in France and A. phagocytophilum anaplasmosis in cattle, horses, dogs and cats in Northern Europe.
The role of various factors have been identified:
- Transport by air, sea, train, and road has literally "exploded" over the last two decades, with intense movements of production animals, sport and leisure animals, and humans. Whether they are carried out for commercial or leisure purposes, these movements provide ideal conditions for the circulation of pathogens if they are not properly controlled.
- Increasing holiday entitlement and travel to ever-more-distant locations promote pathogen exchanges, especially when domestic pets are travelling with their owner. For instance, more and more Northern Europeans go to Spain, Italy, and France during the summer, and their pets may then return to the Netherlands, Belgium, or Germany with leishmaniosis, ehrlichiosis, or babesiosis.
- The creation of parks facilitates the development of tick populations, vectors of numerous diseases, such as Lyme borreliosis. Open-air activities such as trekking, mountain biking or jogging also increase the risk of being bitten.
- The development of large suburban areas, where everyone has his own little garden ... favours the development of arthropod vectors (e.g. ticks, mosquitoes, and biting flies). In other parts of the world, dams, and artificial lakes sometimes create conditions which can be favourable to the development of disease vectors.
- Measures to protect wild fauna, combined with land rehabilitation and management practices, particularly in forestry, have resulted in a proliferation of red deer, roe deer, wild boar, and foxes, which are all hosts for hematophagous arthropods acting as vectors of pathogens or other parasites. For instance, the development of fox populations and their presence in urban environments has resulted in an increase of Echinococcus multilocularis (tapeworm) infestations, which can cause severe parasitic hepatitis in man.
- Global warming is currently associated with unstable weather conditions and acute phenomena: rain, floods, storms, etc. Far from decreasing vector populations, these phenomena promote their demographic expansion. Moreover, small variations in temperature and humidity levels have rapid effects on arthropod populations (fleas, ticks, mosquitoes, sandflies and Culicoides).
Reports were made on the surveillance networks being set up to monitor impact on both human and animal health, since the majority of these diseases are zoonoses.
"The evolution towards effective risk management and raising awareness among professionals and the general public on the topic of climate changes and vector-borne diseases is the main objective of these meetings. Our modern societies do not accept these kinds of risks anymore, they are too well informed, so we have to take the necessary measures well in advance." Concludes Frédéric Beugnet, Technical Director at Merial EMEA and PhD in parasitology.
About Merial
With its involvement in research as well as with its range of products, Merial provides veterinarians, pharmacists and doctors with epidemiological and clinical data, as well as adequate preventive and therapeutic solutions. The Frontline(R) product range (Frontline Spray(R), Frontline Spot On(R) and Frontline Combo(R)) is the current world leader in flea and tick control for cats and dogs (source: Wood Mackenzie 2006 Report) Pirodog(R) is a preventive vaccine against canine babesiosis, Merilym(R) is a preventive vaccine against canine Lyme borreliosis. The Heartgard(R) range is the world leader in canine cardiopulmonary dirofilariosis prevention.
Merial also produces preventive vaccines against Bluetongue in sheep and West Nile virus infection in horses.
(1) diseases caused by parasites
(2) diseases caused by parasites, bacteria or viruses transmitted by the bite of hematophagous arthropods (mainly ticks and mosquitoes)
Contact:
Press contacts: Merial EMEA, Amanda Evans, +33-4-72-72-31-23 /
Amanda.evans@merial.com. Ruder Finn, Mai Tran / Juliette Billaroch,
+33-1-56-81-15-00 / MerialNet@ruderfinn.fr