created by Mario Marino 2009 for www.zanzare.eu
EMCA Workshop 2009 Highlights
created by Mario Marino 2009 for www.zanzare.eu
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created by Mario Marino 2009 for www.zanzare.eu
Nina Paulic
Establishing of the dispersion capacity of Simulium ornatum Meigen, 1818 (complex) larve by application of methylen blue vital dye
Nina Pualić, Aleksandra Ignjatović Ćupina, Marija Zgomba, Dušan Petrić
University of Novi Sad, Faculty of Agriculture, Laboratory for Medical and Veterinary Entomology,T.D.Obradovića 8, 21000
Novi Sad, Serbia
Identification of the dispersion capacity of S. ornatum late instar larvae, by artificial positioning in the upstream uninhabited sections of the stream, distant from typical breeding zones was the main
objective of this study. Further more, the convenience of methylen blue vital marker application as a suitable tool in biological studies of black flies in natural environmental conditions was tested.
Larval marking was performed in methylen blue aqueous solution 25 mg/l and 45 minutes exposition. High portion of visually detectible dyed larvae (about 90%) was recorded, no mortality and high persistence of the dye in the larval body all over the 15 days period.
Tendency of dispersion and successive inhabitation of downstream sections at increasing distances was expressed in majority of larvae (99,33%). The increase of distances covered in function of time
was recorded, starting from 17 m to 93 m after 1 and 15 days, respectively.
Filiz Gunay
Variation in the productivity (Ro), morphology and age specific mortality in Culex quinquefasciatus (Diptera: Culicidae) samples reared at different constant temperatures
Filiz Günay, Ergi Deniz Özsoy and Bulent Alten Hacettepe University Faculty of Science Department of Biology 06800 Beytepe-Ankara-TURKEY
Over the last six years, several vector-borne, parasitic or zoonotic diseases have emerged, re-emerged or spread in the European territory, especially in southern Europe, with major health, ecological, socioeconomical and environmental consequences. Most of these outbreaks are linked to global and local changes
as ecosystems, habitats, rangeland disturbances, mostly instabilities resulting of climatic changes or growth in human populations and their activities.
As we know that the earth’s climate is in a warming phase, a part of which may be due to human activities.
Both local and global changes may independently or in combination have a negative impact on human and animal health by favouring the spread of vector-borne diseases. Recent experiences with West Nile Virus show how diseases may appear in one continent, be transferred to other continents and become widespread
within the space of a very few months. Many of vector-borne diseases are not only dependent upon carriers that are themselves very sensitive to their environment, the local climate and weather, but also have some of the greatest capacities for rapid increase over short periods of time and for rapid evolutionary responses to
new situations.
It is well known that one of the most important factors affecting the biology and morphology of vectors is temperature. Hypothesis is that populations of Cx. quinquefasciatus rearing under different temperature regimes show subtle variations in reproductivity, morphology and also age specific mortality. A purpose of
this work is to evaluate the dissimilarities among cohorts reared at different five constant temperatures (15 oC, 20 oC, 23 oC, 27 oC and 30 oC) using geometric morphometrics and demographic techniques.
Maximum likelihood estimations of the rate of increase in age specific mortality (the b parameter from Gompertz function) were calculated in Culex quinquefasciatus samples reared at different temperatures.
Between temperature comparisons to assess if significant differences in age specific mortality occured rearing the samples at different temperatures were performed via a likelihood ratio test. In that way, variation in age specific mortality in response to temperature was defined in terms of a reaction norm after one
generation of rearing.
Rearing temperatures affected egg, larval and pupal formation and also the lenght of the developmental period from egg to imago. Furthermore, when temperature increased adult longevity decreased for both sexes. While significant differences could be demonstrated among cohorts for predictive parameters such as
net reproductive rate, Ro, and generation time, Tc, no significant differences among the cohorts were found in terms of intrinsic rate of increase, rm, finite rate of increase,, birth (b) and date (d) rates. As we know, the net reproductive rate (Ro), integrates several important variables, and is indicative for the absence (if<1) or
presence (if>1) of potential spread of disease. Therefore, Ro values and the productivity of all cohorts in different temperatures were determined as “presence (if>1)”. Almost 20 parameters in all life stages were used as phsiological variables and these operational taxonomic units were analyzed using Principal
Component Analysis (PCA).
Wing shape was analyzed using 22 wing landmarks following mosquito rearing at constant temperatures.
Geometric morphometric analysis showed that variables in wing shape and size were statistically correlated with rearing temperatures in both sexes..
Christian Engelbrecht
Continuous trapping of adult Asian tiger mosquitoes (Aedes albopictus) with BGSentinel traps reduced the human landing rate and density indices in an urban environment in Cesena, Italy.
Ch. Engelbrecht1, C. Venturelli2, A. Rose3,1, M.Geier3,1
1 University of Regensburg, Regensburg, Germany
2 Dipartimento di Sanità Pubblica, Cesena, Italy
3 Biogents AG, Regensburg, Germany
Background and Objectives:
Mosquito density, longevity and the daily survival probability of mosquitoes are important factors for diseas transmission in vector-borne diseases such as Chikungunya or Dengue fever.
Conventional strategies to control the main vectors of these diseases (Aedes aegypti, syn. Stegomyia aegypti and Ae. albopictus, syn. St. albopicta) and thus to reduce the risk of disease transmission are the reduction of breeding sites and the application of insecticides.
Additional methods that are currently being tested include the release of sterile males and the continuous application of highly efficient mosquito traps. This strategy seems to be especially promising for Aedes aegypti and Ae. albopicus because of their strong adaptation to the urban environment and their limited flight
range.
The objectives of the study presented here was (1) to measure the impact of BG-Sentinel mosquito traps on local Ae. albopictus populations in an urban environment and (2) to compare the standard surveillance method using ovitraps to an adult mosquito monitoring using the BG-Sentinel mosquito traps.
Material and Methods:
The study was conducted during the summer of 2008 in Cesena, Province Forli-Cesena, Emilia Romagna,
Italy. Six clusters with similar urban, geographic and climatic conditions, and population densities for Ae.
albopictus were selected.
Three clusters received treatment with eight BG-Sentinel traps each (intervention), three clusters served as acontrol without adult mosquito traps.
Monitoring was conducted in each cluster by (1) using two ovitraps per cluster, (2) placing one (additional) BG-Sentinel as an adult monitoring trap in intervals of two to five days in every cluster, and (3) by the determination of the human landing rates once per week at the beginning of the study and twice per week later, when mosquito density increased. Captured mosquitoes were collected for later examination.
Eggs in ovitraps were counted in weekly intervals. Mosquitoes collected in the BG-Sentinel traps and in the human bait collections were all determined to species, sexed and counted. Females were dissected to determine their parity by the Detinovas tracheolation method.
Results:
In all parameters measured (human landing rate, parous rate, eggs per week), a clear difference between treatment and control areas was observed. In the clusters with the BG-Sentinel traps, the biting rate of Aedes albopictus was reduced by up to 80%, the density of adult Asian tiger mosquitoes was reduced up to 70%.
The daily survival probability, indirectly measured by the parous rate, was reduced in the treatment areas and the amount of eggs per ovitrap and week was lower in the treatment areas, compared to the control areas (reduction by up to 60%).
Somwang Kurusarttra
Identification of the potential effect of climate change on Dengue epidemic using spatial analysis in Chachoengasao province, Thailand
Somwang Kurusarttra1, Kanchana Nakhapakorn1 and Pattamaporn Kittiyapong2
1Industrial Ecology and Environment Program, Faculty of Environment and Resource Studies, Mahidol University, Nakhon
Pathom 73170, Thailand
2Center for Vectors and Vector-borne Diseases and Department of Biology, Faculty of Science, Mahidol University, Rama 6
Road, Bangkok, 10400, Thailand;
Dengue is a mosquito-borne viral infection causing a constant and serious risk to most tropical regions. As the countries become more developed and environmental transformed from rural to urban, the human population inexorable growth will change global patterns of the disease and mortality. Furthermore, changes in climate pattern phenomenon are thought to be a major contributing factor. Our aim was to indentify the potential effects of climate change on human
health, and in particular, on the incidence of vector-borne diseases. We studied among 11 districts both rural and urban sites in Chachoengsao province, Thailand from 1999 to 2007. Geographic
Information Systems (GIS) has been used to links between georeferenced factors including medical records, demographic data, and climatic data. Using multivariate regression analysis and spatialtemporal modelling, four classes of risk categories have been identified. The nearest neighbourhood method has been allowed to generate a spatial risk map. Dengue incidences in case numbers were significantly associated with climatic variables. The two most significant ones were mean minimum 2-weekly temperatures at t-1 (n = 2530, r2 = 0.245, P = 0.001) and total 2-weekly rainfall during t-2 (n = 2530, r2 = 0.137, P = 0.001). All variables, when entered into the same regression model by stepwise method, together evaluated 66.1% of the total variation in case numbers. At a small temporal scale, we assumed that the changes of land use/cover would not change much. However the predicted regression model implied that dengue epidemics were likely to associate with urbanization and industrialization. Not only they are a suitable ecological niche of denguemosquitoes in term of breeding sites and living habitats, but also urban and industrial increasing effected on the global warming directly. In summary, this research makes advances in dengue
research using GIS spatial analysis for planning prevention and control programs.
Cagasan Karacaoglu
The Use of GIS Tools in Vector Control Programs; Management and Scientific Research
Caglar S.S. and C. Karacaoglu Ç. KARACAOGLU
Hacettepe University Science Faculty Biology Department (ESRL), 06800 Beytepe, Ankara-Turkey
The GIS tools are being widely used in vector control programs. The benefits of these tools can be considered in two different aspects. One of their important role is the planning and management of
vector control programs. Another important role is more scientific that they provide some modelling oppurtinities and information on environment, vectors and parasites, diseases, etc.
Vector control programs are being done in urban, rural, touristic and many other areas all over the world, in different scales. The GIS tools are practical in managing this programs such as online tracking of staff working on field, determining the systematical sampling points, breeding sites, type and amount of insecticides used. By using the data collected and processed in GIS, future planning, predictions and decision making is more effective and easy.
Vectorial diseases can cause epidemics. In both presence and absence of vectorial diseases, if there is a vector than there is always a risk. By using remote sensing and GIS, environmental data,
entomological data, social data and many others can be converted into databases and digitally referenced data. By processing this data, distirbution maps of vectors, diseases risk maps, low and high resolution enviromental maps such as digital elevation, land use, climate maps can be created.
If we go one step further by using this GIS data some simulations with different environmental conditions can be tested for vectorial diseases epidemics.
Emma Orefuwa
The Chikungunya outbreak in the Seychelles: implications for vector control
Emma OREFUWA – Kings College, the University of London, London, UK,
The recent Chikungunya outbreak that swept across the Indian Ocean in 2005-2006 was of unprecedented magnitude. This arbovirus reached the small Indian Ocean Islands of the Seychelles
in July 2005, resulting in a two wave epidemic, totalling 9221 suspected cases, with a peak of 3832 cases in February 2006 and an overall estimated attack rate of 11% (cases from July 05-Oct 07)
The presumed vector of this incapacitating disease among the Islands affected was the container breeding mosquito, Ae. albopictus. To more fully understand the timing and development of the epidemic, an epidemiological profile of notified cases was constructed. The highest number of cases was found in the 15-44 age category which reported 13% of cases. A significant difference
was found in the number of cases reported by women compared to men ( χ2=134.106(1), p<0.0005).
With the backdrop of a high incidence of Chikungunya in Seychelles, Mahe, an ovitrap based survey was carried out for a duration of five weeks, from the 29th August to 6th Oct 2008 in residential and communal areas to study the geographical distribution and abundance of Aedes species during the Winter season.
Ovitrap surveillance was conducted for 5 weeks, conventional ovitraps were placed outside randomly selected houses and communal areas to collect outdoor breeding Aedes mosquitoes. It
was found that Aedes albopictus was the most abundant Aedes species even though a small percentage of Culex quinquesfasciatus was found to breed simultaneously in the same ovitrap.
Aedes aegypti was not found. The results from this survey indicate that the dominant mosquito species is Aedes albopictus, and that during the winter season, there are elevated levels of egg
laying. These findings indicate that monitoring and surveillance initiatives need to be ongoing to identify any risks of any future disease outbreaks that can be transmitted by the Asian ‘tiger’
mosquito.
Andreas Krueger
Tabanids and their medical importance
Andreas Krueger
German Armed Forces – Hospital Hamburg, Dept. Tropical Medicine at the Bernhard Nocht Institute for Tropical Medicine, Labgroup Medical Entomology. Bernhard-Nocht Str. 74, 20359 Hamburg, Germany
Tabanids (clegs, horse flies, deer flies) belong in the order Diptera to the “low” infraorder Tabanomorpha and are represented with over 3500 species worldwide, predominantly in the tropics.
Most of the 160 or so European species are confined to the Mediterranean area. Only the females feed blood on mammals including humans. They are usually diurnal and exophilic as well as
exophagous. They develop in (semi-)aquatic or terrestrial habitats. The optical remote perception of the host is steered by large, dark, heat-emitting objects (also cars!). Tabanids are good and fast
fliers, and a potential host is pursued actively by them.
Adult Tabanus species can be larger than 2 cm. The eyes of many tabanids have a species-specific, brightly coloured pattern of spots or stripes. For Chrysops species dark-brownish wing patterns are
characteristic, while in Haematopota species the wings are greyishly mottled and typically kept roof-like over the abdomen. In particular, the clearly segmented antennae distinguish tabanids from
“higher” flies. The mouthparts superficially resemble the sponging labella of the cyclorrhaph flies.
However, they accommodate stylet-like mandibles and laciniae for piercing the host skin, which leads straight to their medical and economic importance: on one hand the robust proboscis causes
quite painful bites and leaves, on the other hand, relatively large, after-bleeding wounds. These can attract other flies and be thus entrance gates for various secondary infections. In addition, the saliva may cause toxic effects. A massive nuisance of domestic animals can lead to growth inhibition and
reduced milk production. Of special interest is the role of tabanids in the cyclic or mechanical transmission of pathogens to humans and animals. Some Chrysops spp. act as obligatory vectors of
the filaria Loa loa (Nematoda: Spirurida, Onchocercidae), the causative agent of human loiasis disease in Central Africa, where approx. 10 million humans are infected. By migrating of the adult
female worms in the connective tissue (hence the German name „Wanderfilarie“) it comes to swelling („Calabar“- or „Cameroon swelling“) as well as to provoking of the eyes, if the worm
moves under the conjunctiva.
Experimental data suggest the possibility of the mechanical transmission of numerous pathogens,
but the situation in the field is widely unclear. Due to the specific behaviour of tabanids, i) short time feeder (at least Tabanus spp.), ii) causing after-bleeding wounds, iii) predominant zoophily,
and the association of high population densities during respective disease outbreaks, at least a veterinary meaning must be derived for viruses (equine infectious anemia virus, EIA virus), for bacteria (Bacillus anthracis, Francisella tularensis) as well as for certain protozoa of the genus Trypanosoma. Regarding anthrax only once from India species-related data were given for an outbreak, whereby Tabanus indianus, T. bicinctus (=T. biannularis) and Haematopota montana were incriminated. Eventually, in South America tabanids can act as phoretic vehicles for the eggs
of the myiasis-causing human bot-fly Dermatobia hominis.
Dusan Petric
Establishing of the dispersion capacity of Simulium ornatum Meigen, 1818 (complex) larve by application of methylen blue vital dye
Nina Pualić, Aleksandra Ignjatović Ćupina, Marija Zgomba, Dušan Petrić
University of Novi Sad, Faculty of Agriculture, Laboratory for Medical and Veterinary Entomology,T.D.Obradovića 8, 21000
Novi Sad, Serbia
Identification of the dispersion capacity of S. ornatum late instar larvae, by artificial positioning in the upstream uninhabited sections of the stream, distant from typical breeding zones was the main
objective of this study. Further more, the convenience of methylen blue vital marker application as a suitable tool in biological studies of black flies in natural environmental conditions was tested.
Larval marking was performed in methylen blue aqueous solution 25 mg/l and 45 minutes exposition. High portion of visually detectible dyed larvae (about 90%) was recorded, no mortality and high persistence of the dye in the larval body all over the 15 days period.
Tendency of dispersion and successive inhabitation of downstream sections at increasing distances was expressed in majority of larvae (99,33%). The increase of distances covered in function of time
was recorded, starting from 17 m to 93 m after 1 and 15 days, respectively.
Patricia Valle Trujillo
Colonisation patterns of Catalonia (northeast Spain) by the tiger mosquito (Aedes albopictus): trends from 2004 to 2008
Antoni Torrell, Jordi Ruiz, Mariano Rojo: Flora, Fauna and Pet Protection Service, Government of Catalonia, Barcelona, Spain.
Roger Eritja: Mosquito Control Service, Regional Council of El Baix Llobregat, Spain.
Eduard Marquès: Mosquito Control Service of Roses Bay and the Lower Ter, Castelló d’Empúries, Spain.
Presented by: Patricia Valle Trujillo: Public Health Manager – Kenogard Spain.
Aedes albopictus was initially detected in Spain in 2004 (Aranda et al.) in the municipality of St. Cugat del Vallès (Barcelona province). In the last 5 years, the tiger mosquito population has spread, and stable populations of this mosquito being currently to be found in 85 municipalities in Catalonia, potentially affecting over 4 million people.
2005 saw the establishment of a Working Group that comprises the Departments of Health and of the Environment of the Government of Catalonia, Barcelona Provincial Council, the Barcelona Public Health Agency, the Regional Councils of El Baix Llobregat (including the group Mosquito Control Service) and El Vallès Occidental and different municipalities where presence was potential.
To fight the tiger mosquito, this Working Party established the following priorities:
- Communication of the problem, since some preventive control measures on a private level stem from notification.
- Coordination of control work on a municipal scale.
- Monitoring to determine dispersion and the colonisation of new sites by Aedes albopictus.
- Advising population.
In 2005, ovitraps were used to characterise the tiger mosquito population in Catalonia and to accurately determine the municipalities affected and with what intensity.
The 2006 study left no doubt that the tiger mosquito was clearly expanding throughout Catalonia. Not only was it spreading like an oil stain; it was also travelling large distances, which was demonstrated by its presence in municipalities located several kilometres from the initial concentration.
In 2007, monitoring of the species continued to determine its evolution and its rate of expansion, bearing in mind the likelihood that the mosquito would continue to colonise new territories close to those already affected. Nonetheless, the possible appearance of concentrations that were isolated and distant from the risk
area also had to be considered.
The 2008 study has shown that the colonisation of new territories by this mosquito has not stopped, mainly because of: climate, the large number of available breeding sites, and the great mobility of vehicles in Catalonia.
A predictive model is being developed to asses the final scenario for the presence of the species.
Simone Ciadamidaro
Simulium ornatum (complex) in the Province of Rome
Davorka Jaric
Comparison of insecticide toxicity research results performed using induct-test and microcosm
1Josip Milas, 2Branimir K- Hackenberger, 2Davorka Jarić, 2Enrih Merdić
1Public Health Institute of the Osijek-Baranja County, Osijek, Croatia
2Josip Juraj Strossmayer University, Department of Biology, Osijek, Croatia
Abstract:
Induct-test is a standard procedure for testing toxicity of various chemicals for experimental organisms after intraperitoneal (i.p.) administration of tested compound and “incubation” period of 4-12 days, while a microcosm as a procedure for toxicity testing
relies on imitating natural conditions and routes of exposure. Tested insecticides were malathion, temephos and carbofuran. Experimental organisms used were common carp (Cyprinus carpio) in both experiments and, additionally, prussian carp (Carrasius
auratus gibelio) in the induct-test.
Measured enzyme biomarkers in both experiments were: Ethoxyresorufin-O-deethylase (EROD), Total Glutathione (GT), Glutathione-S-transferase (GST), Thiobarbituric Acid
Reactive Substances (TBARS), Acetylcholinesterase activity (AChE) and Catalase activity (CAT). The microcosms contained 150 L of water, 35 specimens of common carp, artificial soil as sediment and 10 specimens of swan mussel (Anodonta cygnea) as a
filter-feeding organism. The pollutants were administered in realistically expected concentrations and 7 fish were sampled every 5 days, with a total of 5 samplings.
The results showed expected differences in biomarker change between induct-test and microcosm experiment (40- to 100-fold). The concentrations used in the induct-test are hardly expected in the environment even if species bioaccumulation potential is taken
into account. On the other hand, the microcosm experiment showed that all biomarkers used in the experiment can detect changes obtained by environmentally realistic concentrations and, therefore, microcosm test has a far more realistic and significant role
in ecological risk assessment of insecticides.
Luigi Avella
Fıeld evaluation of the IGRs, Diflubenzuron, s-methprene, and bactierally-deprived insecticide, spinosad, against Culex pipiens molestus and Aedes albopictus mosquitoes in North-eastern Italy
Dalla Pozza G.1, Avella L. 2,Ceretti G.1 , Baldazzi L.3, Tagliapietra P.1, Ali A.4.
1 Department of Public Health, Azienda ULSS 12 Veneziana, P.le S.L. Giustiniani, 11/D. 30174 Venice, Italy.
2 R&D Department Chemtura Italy Srl, Latina, Italy
3 Via De Carolis, 27. 47900 Rimini, Italy.
4 Mid-Florida Research and Education Center and Department of Entomology and Nematology, University of Florida, 2725
Binion Road, Apopka, Florida 32703, USA
Initially effectiveness and residual activity of three insect growth regulator (IGR) commercial products, Device® SC 15 (15% AI diflubenzuron, flowable), Altosid® SR-10 (5% AI s-methoprene,
microencapsulated), and Proxilar® (4% AI pyriproxyfen, emulsifiable concentrate), and a bacterially-derived insecticide, Laser® (48% AI spinosad, emulsifiable concentrate), were evaluated
against mixed populations of Culex pipiens molestus and Aedes albopictus inhabiting manholes in north-eastern Italy. The test products were applied at recommended field-use rates (label) to the
manholes in Venice-Mestre (Venezia Province) and Riccione (Rimini Province). The post-treatment efficacy of the IGRs and spinosad was judged by monitoring inhibition of adult mosquito emergence (IE) weekly up to 11 weeks post-treatment, compared to the corresponding untreated manholes serving as controls in each study area. Device® SC 15 at 0.75 ppm AI, induced >90% IE of Cx. p. molestus for 8 and 7 weeks post-treatment at Venice-Mestre and Riccione, respectively, while simultaneously yielding similar (>90% IE) control of Ae. albopictus for 9 weeks (Venice-Mestre) and 7 weeks (Riccione) post-treatment. Altosid® SR-10 at 0.75 ppm AI resulted in good control (>90% IE) of both mosquito species for 4-5 weeks post-treatment in the two study areas.
Proxilar® applied at 0.2 ppm caused >90% IE of Cx. p. molestus for 5 weeks (Venice-Mestre) and 4 weeks (Riccione) post-treatment; this IGR gave >90% IE control of Ae. albopictus for 3 and 4 weeks post-treatment at Venice-Mestre and Riccione, respectively. Laser® at 1 ppm AI induced >90% IE of Cx. p. molestus for 8 weeks post-treatment at Venice-Mestre, and for 7 weeks at Riccione,
whereas Ae. albopictus emergence was reduced >90% IE for 6 weeks and 7 weeks posttreatment at the former and latter study area, respectively. Two-way ANOVA and Tuckey test revealed
significantly (P < 0.001) longer post-treatment persistence of Device® SC 15 and Laser® over Altosid® SR-10 and Proxilar® at the treatment rates employed in this study, providing superior
control of the two mosquito species in terms of magnitude and post-treatment time duration.
Roger Eritja
Assessing larvicidal ground-based applications on Aedes albopictus by misting BTI
Roger Eritja
Servei de Control de Mosquits,Consell Comarcal del Baix Llobregat, Parc Torreblanca s/n, 08980Sant Feliu de Llobregat, Spain
Mosquito control in urban environment is a complex topic. Adulticiding applications are restricted by legal issues and larviciding applications using Bacillus thuringiensis israelensis are not cost effective for container-breeding species, because larvae are scattered in many small breeding places in private ground that
cannot be individually sprayed.
The presence of Aedes albopictus in Spain since 2004 has challenged the urban mosquito control in the Baix Llobregat region, performed since 1983 by the Mosquito Control Service of the Baix Llobregat Regional Council in 19 municipalities totalling a population of 879,000 over a surface of 250 sq km. Operations
include larviciding and adulticiding in public areas, education at primary schools, raising concern by spreading information, and promoting suppression of breeding places.
There are strong evidences that the majority of the breeding sites are found in private areas. However, larviciding operators either cannot legally enter the area where the breeding containers are found, or there are too many containers to individually apply Bti by hand. Though such situations can only be managed by
chemical adulticiding, they would be obvious candidates for distance larviciding by misting or cold fogging, provided the availability of suitable Bti formulations.
In cooperation with the manufacturer Valent Biosciences Inc. it was decided to set a test on the performance of misting their Vectobac WDG formulation via a low-volume misting Martignani 748 machine, at a dose of 1 kg of powder per hectare, using adequate dilution rates to accommodate outputs of 200 to 500 liter per
hour.
An array of five single-floor holiday cabins were used to simulate urban conditions in an abandoned camping ground. Small plastic containers ca. 250 ml each were placed in several locations of the housings up to 31 meter from the application path. All tests were duplicated and controls were used. After spraying, they were
brought to the laboratory and populated with Aedes albopictus larvae to assess the mortality rates at 24 and 48 h.
The tested output rates behave slightly differently but a mortality near to 100% could be obtained up to a distance of 20 meter. These promising results will be discussed along to the environmental factors to be considered, as well as further test planning.
Klaus Hoffmann
Using Internet GIS to support the management of helicopter applications in a decentralized organizational structure
Klaus Hoffmann (KABS), Thomas Schorr (Thomas Schorr IT consulting), Norbert Becker (KABS)
Fast flow of indisputable information is a crucial task for mosquito control organisations in executing helicopter application of larvicides with dense daily schedules.
In a decentral organization structure like the German Mosquito Control Association (KABS) a webbased GIS-application warrants optimal performance in an economical manner.
Principal aim of the application is to ensure clear information between all involved parties in a reliable workflow, furthermore documentation and transparency of all up to date and past helicopter treatments in a central database is guaranteed.
The user defined system is entirely based on open source software. Main components are the web application server Zope and the web mapping platform UMN Mapserver.
Key features are:
- Unified, easy to use web interface for all involved actors
- Editing, upload and download function for treatments orders (ESRI-shape file)
- Obligatory workflow for all orders
- Up- and download function for documentation files and tabular summaries
- Download to Google-Earth KML-files of order and documentation files
- Modular contract based development gives a clear overview on costs
- It is open to future enhancements
The presentation will show how a distinct workflow with a huge number of involved parties (32 field officers spread over the upper Rhine valley in Germany and France (Alsace), flight operations
contractor (2 pilots), larvicide supply and workflow management) acting at different locations with different tasks is guaranteed by use of the system.
Panagiotis Pergantas
Mosquito surveillance in Rice fields and Wetlands of Greece – Focus on Evros River in Greek-Turkish Borders.
P. Pergantas, J. Moraitis, M. Botzaki
1: Bioapplications Ltd.
We performed a longitudinal survey of mosquitoes abundance in more than 40 sampling areas in 14 prefectures in Greece with ricefields (approximetly 24.000 ha) and wetlands. Analysis of selected samples showed great differences in abundance in Evros River compared to other areas in Greece with similar enviroments. The hypothesis was that differences were due to Turkish ricefields
(approximately 39.000 ha), situated across the river on the Turkish side, and not to the Evros delta (4.600 ha). We implemented different technologies(GIS, CO₂ traps ,Species Analysis) in order to
monitor the population abundance in three sampling areas consisting of eleven sampling stations.
Each sampling area was a vertical sections across the river with different geomorphological structure. Data analysis of over 135.000 trapped mosquitoes showed differences in species composition and relative decrease in abundance as we move away from the river. Those findings and seasonal distribution, support the hypothesis that mosquitoes nuisance in Evros area is due to Turkish ricefields.
Spiros Mourelatos
Integrated Mosquito Control in Comporta, Portugal
Mourelatos Spiros1, Sandra Gewehr2 and Antonio Moreira3
1Ecodevelopment (Greece)
2Herdade da Comporta (Portugal)
A three-year mosquito control project is carried out by Ecodevelopment at Portugal (a coastal zone, 100 Km south of Lisbon): 2007 (implementation study), 2008 (pilot project), 2009 (foreseen control project). The predominant mosquito species in the region are: Culex theileri (mainly coming from the 1.000 ha of rice fields), Aedes caspius (originating from the coastal wetlands and partially from the rice fields) and Anopheles spp. (exclusively from the rice fields).
A detailed mapping of the most significant reproduction sites of the control area was concluded in 2007: 180 ha of coastal wetlands (ecological mapping) yielded 46 sampling stations; 1076 ha of rice
fields were divided into 611 plots. A first estimation of the productivity of the rice system was made during 2007: samples were taken from the 40% of the total plots of the rice fields on 3 occasions (mid June, July, August).
In 2008, the rice fields, the wetlands and the peri-urban system were monitored exhaustively on a 5-day basis and were treated with Bti when needed. An evaluation of the larval productivity of the
wetlands and the rice fields between years 2007 (no treatment) and 2008 (treatments from mid May to mid September) and adult samplings were made as well. Substantial divergences were found
between the Mediterranean and Atlantic wetlands and rice agro systems in Greece and Portugal respectively and these differences lead to different control strategies.
Maurizio Calvitti
Preliminary characterization of a new Aedes albopictus strain obtained by horizontal transfer of Wolbachia from Culex pipiens
M. Calvitti1, R. Moretti1, R. Bellini2 & S.L. Dobson3
1BAS-Biotec_Agro, C.R. ENEA Casaccia (Roma), Italy;
2CAA ”G.Nicoli” Crevalcore (BO), Italy;
3Dept. Entomology, University of Kentucky (Lexington), KY, USA
Wolbachia (Rickettsiales) is a maternally inherited endosymbiont present in a wide range of insects. Depending on hosts and bacterium strains, the infection may induce Cytoplasmic Incompatibility (CI), a phenomenon of non-viability of embryos resulting from mating of males carrying a specific Wolbachia strain with females that are uninfected or are infected by a different
Wolbachia strain. The release of CI males has the potential for the genetic control of insects,
following the principles of the sterile insect technique. Aedes albopictus is reported to be uniformly superinfected with two Wolbachia strains (wAlbA and wAlbB) throughout its geographical
distribution. Infected males were proved to be fully incompatible with artificially obtained aposymbiotic females.
In this work, we report on the attempt to infect an aposymbiotic strain of Ae. albopictus (RT) with a Wolbachia strain drawn from Culex pipiens embryos (wPip strain). Further experiments were
designed to study the supportive host background and the adaptation of the wPip Wolbachia strain to the new recipient host and evaluate the infection dynamics key parameters like (i) CI level and (ii) maternal inheritance in the new host-Wolbachia association.
About 7.6% of the Ae. albopictus embryos survived the microinjection procedure. About 11% of the adults developed from microinjected embryos were infected with Wolbachia wPip strain. The progeny obtained from two females were found infected and used to establish the new transinfected Ae. albopicuts line (RTP) and then perform the subsequent tests.
CI was very high in all crosses between RTP males and females characterized by a different infection status. No viable eggs (i.e. high CI) were found in the reciprocal cross between normal superinfected males and RTP females as well. Maternal inheritance was found close to 100%.
Further studies are focusing on the analysis of the potential fitness costs associated with the new infection in terms of immature and adult survival, fecundity and egg hatching rate.
Results are discussed in relation to the possibility of using the new Ae. albopictus–Wolbachia symbiosis as suitable system for the study and development of CI-based strategies for the suppression of the vector population.
Alessandro Albieri
Monitoring of Aedes albopictus (skuse) in emilia-romagna: cluster investigation and geostatistical analysis
Albieri A.1, Carrieri M. 1, Angelini P.2., Baldacchini F.2, Venturelli C.3, Mascali Zeo S.3, Bellini R. 1
1Centro Agricoltura Ambiente “G.Nicoli”, Medical & Veterinary Entomology Dept., Italy
2Emilia Romagna Region Public Health Dept., Italy
3Emilia Romagna Region Public Health Dept., Urban and Health Entomology Dept., Italy
The Emilia-Romagna Regional Aedes albopictus (Skuse) control project use ovitraps as tools for mosquito population density estimation.
2,741 ovitraps have been positioned in urban areas using standard criteria and checked weekly during the favourable season 2008. Distance between ovitraps is fixed in the range 200-800 m.
The estimation of distribution and abundance based on ovitraps or on mean eggs density for municipalities provide only point data and not a continuous spatial distribution of the target species.
Kriging interpolation was used to estimate seasonal abundance of the species at unsampled locations throughout the study area, and cluster analysis was used to identify particular areas that had consistently high or low mosquito density statistically significant.
Definition of large geographic areas with consistently high or low abundance of Ae.albopictus may provide information on environmental variables that promote species diffusion and on disease risk surveillance programs (Chikungunya and Dengue surveillance in Emilia-Romagna).
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