The purpose of this review is to provide practical information to help researchers intending to perform \"from field to laboratory\" studies on phleboviruses transmitted by sandflies. This guideline addresses the different steps to be considered starting from the field collection of sandflies to the laboratory techniques aiming at the detection, isolation, and characterization of sandfly-borne phleboviruses. In this guideline article, we address the impact of various types of data for an optimal organization of the field work intending to collect wildlife sandflies for subsequent virology studies. Analysis of different data sets should result in the geographic positioning of the trapping stations. The overall planning, the equipment and tools needed, the manpower to be deployed, and the logistics to be anticipated and set up should be organized according to the objectives of the field study for optimal efficiency.

In this series of review articles entitled \"Practical guidelines for studies on sandfly-borne phleboviruses,\" the important points to be considered at the prefieldwork stage were addressed in part I, including parameters to be taken into account to define the geographic area for sand fly trapping and how to organize field collections. Here in part II, the following points have been addressed: (1) factors influencing the efficacy of trapping and the different types of traps with their respective advantages and drawbacks, (2) how to process the trapped sand flies in the field, and (3) how to process the sand flies in the virology laboratory. These chapters provide the necessary information for adopting the most appropriate procedures depending on the requirements of the study. In addition, practical information gathered through years of experience of translational projects is included to help newcomers to fieldwork studies.

BACKGROUND: West Nile virus (WNV) is a zoonotic mosquito-borne virus with a broad host range that infects mainly birds and mosquitos, but also mammals (including humans), reptiles, amphibians and ticks. It is maintained in a bird-mosquito-bird transmission cycle. The most important vectors are bird-feeding mosquitos of the Culex genus; maintenance and amplification mainly involve passerine birds. WNV can cause disease in humans, horses and several species of birds following infection of the central nervous system.
UNASSIGNED: Cats can also be infected through mosquito bites, and by eating infected small mammals and probably also birds. Although seroprevalence in cats can be high in endemic areas, clinical disease and mortality are rarely reported. If a cat is suspected of clinical signs due to an acute WNV infection, symptomatic treatment is indicated.

BACKGROUND: Understanding the mechanisms that influence the population dynamics and spatial genetic structure of the vectors of pathogens infecting humans is a central issue in tropical epidemiology. In view of the rapid changes in the features of landscape pathogen vectors live in, this issue requires new methods that consider both natural and human systems and their interactions. In this context, individual-based model (IBM) simulations represent powerful yet poorly developed approaches to explore the response of pathogen vectors in heterogeneous social-ecological systems, especially when field experiments cannot be performed.
RESULTS: We first present guidelines for the use of a spatially explicit IBM, to simulate population genetics of pathogen vectors in changing landscapes. We then applied our model with Triatoma brasiliensis, originally restricted to sylvatic habitats and now found in peridomestic and domestic habitats, posing as the most important Trypanosoma cruzi vector in Northeastern Brazil. We focused on the effects of vector migration rate, maximum dispersal distance and attraction by domestic habitat on T. brasiliensis population dynamics and spatial genetic structure. Optimized for T. brasiliensis using field data pairwise fixation index (FST) from microsatellite loci, our simulations confirmed the importance of these three variables to understand vector genetic structure at the landscape level. We then ran prospective scenarios accounting for land-use change (deforestation and urbanization), which revealed that human-induced land-use change favored higher genetic diversity among sampling points.
CONCLUSIONS: Our work shows that mechanistic models may be useful tools to link observed patterns with processes involved in the population genetics of tropical pathogen vectors in heterogeneous social-ecological landscapes. Our hope is that our study may provide a testable and applicable modeling framework to a broad community of epidemiologists for formulating scenarios of landscape change consequences on vector dynamics, with potential implications for their surveillance and control.

Many novel approaches to controlling mosquito vectors through the release of sterile and mass reared males are being developed in the face of increasing insecticide resistance and other limitations of current methods. Before full scale release programmes can be undertaken there is a need for surveillance of the target population, and investigation of parameters such as dispersal and longevity of released, as compared to wild males through mark-release-recapture (MRR) and other experiments, before small scale pilot trials can be conducted. The nature of the sites used for this field work is crucial to ensure that a trial can feasibly collect sufficient and relevant information, given the available resources and practical limitations, and having secured the correct regulatory, community and ethical approvals and support. Mauritius is considering the inclusion of the sterile insect technique (SIT), for population reduction of Aedes albopictus, as a component of the Ministry of Health and Quality of Life\'s \'Operational Plan for Prevention and Control of Chikungunya and Dengue\'. As part of an investigation into the feasibility of integrating the SIT into the Integrated Vector Management (IVM) scheme in Mauritius a pilot trial is planned. Two potential sites have been selected for this purpose, Pointe des Lascars and Panchvati, villages in the North East of the country, and population surveillance has commenced. This case study will here be used to explore the considerations which go into determining the most appropriate sites for mosquito field research. Although each situation is unique, and an ideal site may not be available, this discussion aims to help researchers to consider and balance the important factors and select field sites that will meet their needs.

BACKGROUND: The recent notifications of autochthonous cases of dengue and chikungunya in Europe prove that the region is vulnerable to these diseases in areas where known mosquito vectors (Aedes albopictus and Aedes aegypti) are present. Strengthening surveillance of these species as well as other invasive container-breeding aedine mosquito species such as Aedes atropalpus, Aedes japonicus, Aedes koreicus and Aedes triseriatus is therefore required. In order to support and harmonize surveillance activities in Europe, the European Centre for Disease Prevention and Control (ECDC) launched the production of \'Guidelines for the surveillance of invasive mosquitoes in Europe\'. This article describes these guidelines in the context of the key issues surrounding invasive mosquitoes surveillance in Europe.
METHODS: Based on an open call for tender, ECDC granted a pan-European expert team to write the guidelines draft. It content is founded on published and grey literature, contractor\'s expert knowledge, as well as appropriate field missions. Entomologists, public health experts and end users from 17 EU/EEA and neighbouring countries contributed to a reviewing and validation process. The final version of the guidelines was edited by ECDC (Additional file 1).
RESULTS: The guidelines describe all procedures to be applied for the surveillance of invasive mosquito species. The first part addresses strategic issues and options to be taken by the stakeholders for the decision-making process, according to the aim and scope of surveillance, its organisation and management. As the strategy to be developed needs to be adapted to the local situation, three likely scenarios are proposed. The second part addresses all operational issues and suggests options for the activities to be implemented, i.e. key procedures for field surveillance of invasive mosquito species, methods of identification of these mosquitoes, key and optional procedures for field collection of population parameters, pathogen screening, and environmental parameters. In addition, methods for data management and analysis are recommended, as well as strategies for data dissemination and mapping. Finally, the third part provides information and support for cost estimates of the planned programmes and for the evaluation of the applied surveillance process.
CONCLUSIONS: The \'Guidelines for the surveillance of invasive mosquitoes in Europe\' aim at supporting the implementation of tailored surveillance of invasive mosquito species of public health importance. They are intended to provide support to professionals involved in mosquito surveillance or control, decision/policy makers, stakeholders in public health and non-experts in mosquito surveillance. Surveillance also aims to support control of mosquito-borne diseases, including integrated vector control, and the guidelines are therefore part of a tool set for managing mosquito-borne disease risk in Europe.

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We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

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Most new vector control methods against malaria involve the use of pesticides. Prior to release of these products for general use, their efficacy, persistence, and cross-resistance must be tested on mosquito colonies raised in the laboratory (phase I) then on wild mosquitoes in the field (small-scale), individual dwellings, or experimental huts (phase II). The goal of phase III studies is to evaluate the efficacy and effectiveness of the vector-control product or method against malaria in a population at regular risk for transmission. The main objective of phase III tests is to measure the epidemiologic impact, e.g. on the incidence or prevalence of malaria in humans. This article presents guidelines for carrying out phase III tests of vector-control methods against malaria (e.g. home insecticide spraying or insecticide-impregnated bednet use). It was written by participants in a workgroup formed to define recommendations for the WHOPES (WHO Pesticide Evaluation Scheme).