Tunis, Tunisia (ots/PRNewswire) -
- 6th Merial Symposium on Parasitosis & Arthropod-Borne Diseases:
A Bio- Mathematical Model for the Risk Evaluation of Flea & Tick
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
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:
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
- satellite mapping - to monitor the emergence and distribution
of diseases related to vegetation & human activities, and
- climatic modelling - to follow parasite activity caused by
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:
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,
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.
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)
ots Originaltext: Merial
Im Internet recherchierbar: http://www.presseportal.ch
Press contacts: Merial EMEA, Amanda Evans, +33-4-72-72-31-23 /
Amanda.firstname.lastname@example.org. Ruder Finn, Mai Tran / Juliette Billaroch,
+33-1-56-81-15-00 / MerialNet@ruderfinn.fr