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This Scientific Opinion addresses a European Commission request on the welfare of calves as part of the Farm to Fork strategy. EFSA was asked to provide a description of common husbandry systems and related welfare consequences, as well as measures to prevent or mitigate the hazards leading to them. In addition, recommendations on three specific issues were requested: welfare of calves reared for white veal (space, group housing, requirements of iron and fibre); risk of limited cow–calf contact; and animal-based measures (ABMs) to monitor on-farm welfare in slaughterhouses. The methodology developed by EFSA to address similar requests was followed. Fifteen highly relevant welfare consequences were identified, with respiratory disorders, inability to perform exploratory or foraging behaviour, gastroenteric disorders and group stress being the most frequent across husbandry systems. Recommendations to improve the welfare of calves include increasing space allowance, keeping calves in stable groups from an early age, ensuring good colostrum management and increasing the amounts of milk fed to dairy calves. In addition, calves should be provided with deformable lying surfaces, water via an open surface and long-cut roughage in racks. Regarding specific recommendations for veal systems, calves should be kept in small groups (2–7 animals) within the first week of life, provided with ~ 20 m2/calf and fed on average 1 kg neutral detergent fibre (NDF) per day, preferably using long-cut hay. Recommendations on cow–calf contact include keeping the calf with the dam for a minimum of 1 day post-partum. Longer contact should progressively be implemented, but research is needed to guide this implementation in practice. The ABMs body condition, carcass condemnations, abomasal lesions, lung lesions, carcass colour and bursa swelling may be collected in slaughterhouses to monitor on-farm welfare but should be complemented with behavioural ABMs collected on farm. info:eu-repo/semantics/publishedVersion

In this Opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of certain kept fish species have been assessed. Atlantic salmon (Salmo salar), carp (Cyprinus spp.), rainbow trout (Oncorhynchus mykiss), sea bream (Sparus aurata) and tilapia (Oreochromis spp.), selected as representative of the most important fish species and production systems that are commercially reared in fresh and saltwater farms, were the focus of this assessment. The assessment was performed following a methodology based on information collected by an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate Opinion. The global state of play of antimicrobial resistance in Aeromonas hydrophila, Aeromonas salmonicida, Flavobacterium psychrophilum and Flavobacterium columnare is provided. Among these bacteria, none was identified as being among the most relevant antimicrobial-resistant bacteria in the assessed kept fish species in the EU due to the very limited scientific evidence available. info:eu-repo/semantics/publishedVersion

In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of pigs have been assessed. The assessment has been performed following a methodology based on information collected by an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial resistant Escherichia coli, Streptococcus suis, Actinobacillus pleuropneumoniae, Pasteurella multocida, Glaeserella parasuis, Bordetella bronchiseptica, Staphylococcus aureus, Staphylococcus hyicus, Brachyspira hyodysenteriae, Trueperella pyogenes, Erysipelothrix rhusiopathiae, Streptococcus dysgalactiae, Mycoplasma hyosynoviae, Mycoplasma hyorhinis, Mycoplasma hyopneumoniae and Brachyspira pilosicoli has been provided. Among those bacteria, EFSA identified E. coli and B. hyodysenteriae with > 66% certainty as being the most relevant antimicrobial resistant bacteria in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions. info:eu-repo/semantics/publishedVersion

In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of horses have been assessed. The assessment has been performed following a methodology composed of information collected via an extensive literature review and expert judgement. Details on the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial-resistant Actinobacillus equuli, Dermatophilus congolensis, Enterococcus spp., Escherichia coli, Klebsiella pneumoniae, Pasteurella spp., Pseudomonas aeruginosa, Rhodococcus equi, Staphylococcus aureus and Streptococcus dysgalactiae subsp. dysgalactiae/equisimilis and Streptococcus equi subsp. equi and subsp. zooepidemicus has been provided. Among those bacteria, EFSA identified E. coli, Staphylococcus aureus and R. equi with more than 66% certainty as the most relevant antimicrobial-resistant bacteria in the EU, given their importance as causative agents of clinical disease in horses and the significant levels of resistance to clinically relevant antimicrobials. The animal health impact of these ‘most relevant’ bacteria as well as their eligibility of being listed and categorised within the animal health law framework will be assessed in separate scientific opinions. info:eu-repo/semantics/publishedVersion

In this opinion, the antimicrobial resistant bacteria responsible for transmissible diseases that constitute a threat to the health of cattle have been assessed. The assessment has been performed following a methodology based on information collected by an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play on antimicrobial resistance in clinical isolates of Escherichia coli (non-VTEC), Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Pasteurella multocida, Mannheimia haemolytica, Histophilus somni, Mycoplasma bovis, Moraxella bovis, Fusobacterium necrophorum and Trueperella pyogenes is provided. Among those bacteria, EFSA identified E. coli and S. aureus with ≥ 66% certainty as being the most relevant antimicrobial resistant bacteria in cattle in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions. info:eu-repo/semantics/publishedVersion

In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of farmed rabbits have been assessed. The assessment has been performed following a methodology based on information collected through an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play on antimicrobial resistance in clinical isolates of Pasteurella multocida, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Bordetella bronchiseptica, Clostridium difficile, Clostridium perfringens and Clostridium spiroforme is provided. Among these bacteria, none were identified as being the most relevant antimicrobial-resistant bacteria in rabbits in the EU due to the very limited scientific evidence available. info:eu-repo/semantics/publishedVersion

The European Commission requested that EFSA provide study designs for the investigation of four research domains according to major gaps in knowledge identified by EFSA in a report published in 2019: (i) the patterns of seasonality of African Swine Fever (ASF) in wild boar and domestic pigs in the EU; (ii) the epidemiology of ASF in wild boar; (iii) survival of ASF virus (ASFV) in the environment and (iv) transmission of ASFV by vectors. In this Scientific Opinion, the fourth research domain on ASFV transmission by vectors is addressed. Eleven research objectives were proposed by the EFSA working group and broader ASF expert networks, such as ASF stop, ENETWILD, VectorNet, AHAW network and the AHAW Panel Experts. Of the 11 research objectives, six were prioritised based on the following set of criteria: (1) the impact on ASF management; (2) the feasibility or practicality to carry out the study; (3) the potential implementation of study results in practice; (4) a possible short time-frame study (< 1 year); (5) the novelty of the study and (6) if it was a priority for risk managers. The prioritised research objectives were: (I) Studies on the potential vector fauna at the pig-wild boar interface and the feeding preference of blood-feeding potential vectors in ASF-affected areas; (II) Assessment of the efficacy of insect screens on indoor/outdoor pig holdings to prevent the entry of blood-sucking vectors (i.e. Stomoxys) in ASF endemic areas; (III) Assess the role of mechanical vectors in the virus transmission in ASF-affected areas; (IV) Distribution of the potential mechanical transmission vectors in ASF-affected areas of the EU; (V) ASFV transmission by synanthropic birds; and (VI) Assessment on the presence/absence of the soft tick Ornithodoros erraticus in ASF-affected areas in Europe. For each of the selected research objectives, a research protocol has been proposed considering the potential impact on ASF management and the period of 1 year for the research activities. (C) 2021 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

The European Commission requested that EFSA provide study designs for the investigation of four research domains according to major gaps in knowledge identified by EFSA in a report published in 2019: i) the patterns of seasonality of African Swine Fever (ASF) in wild boar and domestic pigs in the EU; ii) the epidemiology of ASF in wild boar; iii) survival of ASF virus (ASFV) in the environment and iv) transmission of ASFV by vectors. In this Scientific Opinion, the third research domain on ASFV survival is addressed. Nine research objectives were proposed by the working group and broader ASF expert networks, such as ASF stop, ENETWILD, VectorNet, AHAW network and the AHAW Panel Experts. Of the nine research objectives, only one was prioritised and elaborated into a general protocol/study design research proposal, pertaining ASFV survival in feed and bedding. To investigate the survival of ASFV in feed, bedding and roughage, laboratory survival studies are proposed. To investigate possible risk mitigation measures, proof-of-concept approaches should be investigated. (C) 2021 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

In this opinion the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to dog and cat health have been assessed. The assessment has been performed following a methodology based on information collected via an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial resistant Staphylococcus pseudintermedius, Staphylococcus aureus, Staphylococcus schleiferi, Escherichia coli, Proteus mirabilis, Klebsiella spp., Enterobacter spp., Pseudomonas aeruginosa, Clostridium perfringens, Clostridioides difficile, Enterococcus faecalis and Enterococcus faecium has been provided. Among those bacteria, EFSA identified S. pseudintermedius, E. coli and P. aeruginosa with > 90% certainty as the most relevant antimicrobial resistant bacteria in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions. (C) 2021 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Since the first detection of Xylella fastidiosa (XF) in Majorca (Spain) five years ago, this phytopathogenic bacterium has been found in the rest of the Balearic Islands except Formentera. In the Balearic archipelago, the expansion of the XF infection occurs through the feeding activity of the spittlebugs Philaenus spumarius and Neophilaenus campestris (Aphrophoridae). To date, these are the only confirmed XF vectors in the Balearic Islands. In 2017 we started a project granted by EFSA aiming at, among other objectives, DNA barcoding putative vectors in the Balearics through the analysis of the standardized 5’ end of the mitochondrial COI gene of the insects. Moreover, a cytB mtDNA fragment was also sequenced in order to expand the genetic dataset and to conduct phylogenetic inferences. We take advantage of the P. spumarius and N. campestris DNA sequences available at GenBank to investigate the molecular systematics of the Balearic vectors and the patterns of haplotype divergence among vector populations in Europe., ES; PPT; sofia.delgado@uib.es

The European Commission requested EFSA assess antimicrobial-resistant bacteria responsible for animal transmissible diseases, with a view to listing such pathogens for European Union action. This Scientific Opinion addresses the ad hoc method developed: (i) to give a global state of play as regards resistant animal pathogens that cause transmissible animal diseases, (ii) to identify the most relevant bacteria in the EU and (iii) to summarise their actual or potential animal health impact, and to perform their assessment for being listed and categorised according to the criteria of Articles 7, 5, 9 and 8 within the Animal Health Law (AHL) framework. An extensive literature review is carried out to give the global state of play of selected resistant bacteria that constitute a threat to animal health (i). An expert judgement procedure, based on the outcome of the literature review, is applied to identify which among those bacteria subjected to the literature review are the 'most relevant' in the European Union (ii). Their animal health impact in the European Union and their assessment for being listed and categorised according to the AHL framework will follow the 'ad hoc method for the assessment on listing and categorisation of animal diseases within the framework of the Animal Health Law' that EFSA has developed in the past (iii). The assessment of (i) and (ii) is addressed in distinct scientific opinions that are published separately by animal species of interest (dogs and cats, horses, pigs, poultry, cattle, small ruminants, rabbits and aquatic animal species). The assessment of (iii) is addressed in distinct scientific opinions and published separately by the animal pathogen. (c) 2021 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

The European Commission asked EFSA to provide study designs for the investigation of four research domains (RDs) according to major gaps in knowledge identified by EFSA in a report published in 2019: (RD 1) African swine fever (ASF) epidemiology in wild boar; (RD 2) ASF transmission by vectors; (RD 3) African swine fever virus (ASFV) survival in the environment, and (RD 4) the patterns of seasonality of ASF in wild boar and domestic pigs in the EU. In this Scientific Opinion, the second RD on ASF epidemiology in wild boar is addressed. Twenty-nine research objectives were proposed by the working group and broader ASF expert networks and 23 of these research objectives met a prespecified inclusion criterion. Fourteen of these 23 research objectives met the predefined threshold for selection and so were prioritised based on the following set of criteria: (1) the impact on ASF management; (2) the feasibility or practicality to carry out the study; (3) the potential implementation of study results in practice; (4) a possible short time-frame study (< 1 year); (5) the novelty of the study; and (6) if it was a priority for risk managers. Finally, after further elimination of three of the proposed research objectives due to overlapping scope of studies published during the development of this opinion, 11 research priorities were elaborated into short research proposals, considering the potential impact on ASF management and the period of one year for the research activities. (C) 2021 European Food Safety Authority.

cet article a fait l’objet d’une correctionDOI : 10.1186/s13071-020-04349-y; International audience; ackgroundCulicoides obsoletus is an abundant and widely distributed Holarctic biting midge species, involved in the transmission of bluetongue virus (BTV) and Schmallenberg virus (SBV) to wild and domestic ruminants. Females of this vector species are often reported jointly with two morphologically very close species, C. scoticus and C. montanus, forming the Obsoletus/Scoticus Complex. Recently, cryptic diversity within C. obsoletus was reported in geographically distant sites. Clear delineation of species and characterization of genetic variability is mandatory to revise their taxonomic status and assess the vector role of each taxonomic entity. Our objectives were to characterize and map the cryptic diversity within the Obsoletus/Scoticus Complex.MethodsPortion of the cox1 mitochondrial gene of 3763 individuals belonging to the Obsoletus/Scoticus Complex was sequenced. Populations from 20 countries along a Palaearctic Mediterranean transect covering Scandinavia to Canary islands (North to South) and Canary islands to Turkey (West to East) were included. Genetic diversity based on cox1 barcoding was supported by 16S rDNA mitochondrial gene sequences and a gene coding for ribosomal 28S rDNA. Species delimitation using a multi-marker methodology was used to revise the current taxonomic scheme of the Obsoletus/Scoticus Complex.ResultsOur analysis showed the existence of three phylogenetic clades (C. obsoletus clade O2, C. obsoletus clade dark and one not yet named and identified) within C. obsoletus. These analyses also revealed two intra-specific clades within C. scoticus and raised questions about the taxonomic status of C. montanus.ConclusionsTo our knowledge, our study provides the first genetic characterization of the Obsoletus/Scoticus Complex on a large geographical scale and allows a revision of the current taxonomic classification for an important group of vector species of livestock viruses in the Palaearctic region.

EFSA Panel on Animal Health and Welfare (AHAW)., The killing of pigs for human consumption (slaughtering) can take place in a slaughterhouse or on farm. The processes of slaughtering that were assessed for welfare, from the arrival of pigs until their death, were grouped into three main phases: pre‐stunning (including arrival, unloading from the truck, lairage, handling and moving of pigs); stunning (including restraint); and bleeding. Stunning methods were grouped into three categories: electrical, controlled atmosphere and mechanical. Twelve welfare consequences the pigs can be exposed to during slaughter were identified: heat stress, cold stress, fatigue, prolonged thirst, prolonged hunger, impeded movement, restriction of movements, resting problem, negative social behaviour, pain, fear and respiratory distress. Welfare consequences and relevant animal‐based measures were described. In total, 30 welfare hazards that could occur during slaughter were identified and characterised, most of them related to stunning and bleeding. Staff were identified as the origin of 29 hazards, which were attributed to the lack of appropriate skill sets needed to perform tasks or to fatigue. Corrective and preventive measures for these hazards were assessed: measures to correct hazards were identified, and management was shown to have a crucial role in prevention. Outcome tables linking hazards, welfare consequences, animal‐based measures, origins and preventive and corrective measures were developed for each process. Mitigation measures to minimise welfare consequences are proposed.

Background: Culicoides biting midges are hematophagous insects of veterinary importance able to transmit viruses such as bluetongue virus and Schmallenberg virus to livestock. The aim of this work was to describe the average temporal abundance of biting midges at a continental scale, by comparing the seasonal variation at six different latitude ranges from southern Spain to northern Sweden. Materials and methods: We gathered Culicoides obsoletus group trap data collected by national surveillance programs in nine European countries (Spain, France Germany, Switzerland, Austria, Denmark, Sweden, Norway, Poland) from 2007-2013. In total, 904 farms were sampled for Culicoides midges using UV light traps. We divided Europe into 6 latitudinal bands of 5° width and calculated the average weekly midge abundance as well as the average annual cumulative sum of biting midges for each of these bands. We plotted the results to visualize the spatial and temporal patterns at a continental scale. Results: The midge season began earlier in southern Europe (week 10) compared to northern latitudes (week 19). The season also lasted longer at southern latitudes and became progressively shorter towards the northern latitudes. Abundance peaks occurred during spring and summer at all six latitudinal ranges. Despite the steadily shorter vector season in the north of Europe, the annual cumulative sum of biting midges increased towards the north. Norway and Sweden with the shortest vector periods, had the highest number of the C. obsoletus group, reaching a cumulative sum of 455.000 midges on average annually, with some traps collecting more than 110.000 in one night. Discussion: Temperature drives the start and length of the midge season at different latitudes, but it does not seem to drive the increasing abundance towards the north. A possible explanation could be that midge abundance may be more related to breeding site availability and soil moisture than temperature. Conclusion: This is the first time quantitative seasonal abundances for biting midges have been aggregated and jointly analyzed for the whole of Western Europe. By ignoring the fine scale variation in abundance between farms and regions, we have isolated and quantified an overall south-north trend in the temporal abundance of biting midges. These results may facilitate decision making by e.g. the EU member states when objectives and joint decisions are needed for prevention and control of midge-borne infections on a continental scale.

[eng] Over the last century, vector-borne pathogens have spread to new areas, creating novel public health challenges. As major arthropod disease vectors, mosquitoes represent a significant, growing threat to human health due to their role in disease transmission. Personal protection products such as insecticides and repellents are useful tools available to the general public that can decrease disease incidence and mosquito-related nuisances by reducing contact frequency between mosquitoes and their hosts. However, European Union regulations have become increasingly strict because biocide use generates toxicological risks for human and environmental health. The doctoral research presented herein sought to 1) validate new laboratory and field methodologies and 2) explore alternative parameters and/or approaches for evaluating insecticides and repellents. To this end, four studies were conducted using Aedes albopictus (Skuse, 1894), Culex pipiens (Linnaeus, 1758), and human volunteers. The first study estimated the landing rate outdoors in an area infested with the Asian tiger mosquito (Ae. albopictus) and replicated this rate in the laboratory. More specifically, 16 study participants were exposed to mosquitoes in a highly infested region of Italy. These field results were compared to laboratory results obtained in 1) a 30-m3 room where 9 volunteers were exposed to different numbers of mosquitoes (15–50) and 2) a 0.064-m3 AIC test cage containing 200 mosquitoes. The highest mosquito landing rate in the field was 26.8 landings/min. In the room test, a similar landing rate was achieved using 15–20 mosquitoes and an exposure time of 3 min. In the AIC test, the landing rate was 229 ± 48 landings/min. This study is the first to concomitantly measure and compare Ae. albopictus landing rates in the field and laboratory. The second study assessed alternative laboratory methods for evaluating topical mosquito repellents and took place at three European testing laboratories. Each test utilised female Ae. albopictus and 30 study participants. First, a conventional AIC test and a sleeved AIC test were performed using exposed arm areas of 600 and 100 cm2, respectively, and cage volumes of 0.040 and 0.064 m3, respectively. Mosquito density was consistently 1 female/840 cm3. Second, room-based testing (40 ± 5 mosquitoes in 25–30 m3) was used as a proxy for field testing. A mosquito repellent (15% N,N-diethylm- toluamide) was employed at two doses: 1 and 0.5 g/600 cm2. The two new methods showed themselves to be good alternatives to conventional AIC testing and yielded reproducible protection times across laboratories. The third study used the room test to evaluate the effects of sublethal insecticide doses used in spatial treatments on mosquito fitness; protection against mosquito bites in humans; and toxicological risks to human and environmental health. This work employed a synthetic type I pyrethroid, prallethrin, at three sublethal doses (0.40 ± 0.01 mg/h, 0.80 ± 0.01 mg/h, and 1.60 ± 0.01 mg/h) and utilised colonies of Ae. albopictus and Cx. pipiens. The results showed that sublethal doses reduced mosquito survival, influencing population size in the next generation. The doses also provided 100% protection to human hosts and presented limited risks to human and environmental health. The fourth study explored how well sublethal doses of spatial repellents could protect people from bites outdoors. Two field experiments were performed in Italy in an area with high Ae. albopictus abundance using a synthetic type I pyrethroid, transfluthrin, in aerosol form. The first examined levels of protection for humans, and the second examined mosquito knockdown and mortality. Percent protection for humans remained high (>80%) at 5 h despite the absence of mosquito mortality at 1 h. This study showed that sublethal doses could be useful: they protected human hosts even when mosquito mortality was null. [spa] Los mosquitos representan una amenaza importante y creciente para la salud humana debido a su papel en la transmisión de enfermedades. Productos de protección personal, como insecticidas y repelentes, pueden disminuir la incidencia de enfermedades y las molestias relacionadas con los mosquitos al reducir la frecuencia de contacto entre ellos y sus huéspedes. Sin embargo, la regulación de biocidas se ha vuelto cada vez más estricta debido a que su uso puede generar riesgos toxicológicos para la salud humana y medioambiental. La presente tesis doctoral buscó 1) validar nuevas metodologías de laboratorio y de campo y 2) explorar parámetros y/o enfoques alternativos para evaluar insecticidas y repelentes. Para ello se llevaron a cabo cuatro estudios utilizando Aedes albopictus (Skuse, 1894), Culex pipiens (Linnaeus, 1758) y voluntarios humanos. El primer estudio involucró a 16 participantes que evaluaron la tasa de aterrizaje de mosquitos en un área naturalmente infestada por Ae. albopictus. Los resultados obtenidos se compararon con estudios de laboratorio llevados a cabo en 1) una cabina de 30 m3 donde 9 voluntarios fueron expuestos a diferente número de mosquitos (15–50) y 2) una jaula de 0,064 m3 que contenía 200 mosquitos, test conocido como arm-in-cage (AIC). La tasa de aterrizaje de mosquitos más alta en el campo fue de 26,8 aterrizajes/min. El ensayo en la cabina logró una tasa similar utilizando 15 - 20 mosquitos y un tiempo de exposición de 3 min. En el AIC, la tasa fue de 229 ± 48 aterrizajes/min. Este estudio es el primero en medir y comparar tasas de aterrizaje en campo y laboratorio con Ae. albopictus. El segundo estudio exploró métodos de laboratorio alternativos para evaluar repelentes de mosquitos de uso tópico. Se realizó en cuatro laboratorios europeos; se utilizaron hembras de Ae albopictus y 30 participantes por configuración. 1) Se comparó resultados de protección con el AIC convencional (áreas de brazo expuestas de 600 cm2) versus el AIC con manguito (100 cm2) y volúmenes de jaula de entre 0,040 y 0,064 m3. La densidad de mosquitos fue de 1 hembra/840 cm3. 2) se utilizaron cabinas de entre 25– 30 m3 con 40 ± 5 mosquitos. Se empleó 15% N,N-dietil-m-toluamida en dos dosis: 1 y 0,5 g/600 cm2. Los dos nuevos métodos demostraron ser buenas alternativas al AIC convencional produciendo tiempos de protección reproducibles en todos los laboratorios. El tercer estudio evaluó en laboratorio los efectos de dosis subletales de insecticidas utilizadas en tratamientos espaciales sobre 1) el estado físico de los mosquitos; 2) protección contra las picaduras de mosquitos en humanos; y 3) riesgos toxicológicos para la salud humana y ambiental. Este trabajo empleó un piretroide sintético tipo I, praletrina, en tres dosis subletales (0,40 ± 0,01 mg/h, 0,80 ± 0,01 mg/h y 1,60 ± 0,01 mg/h) y utilizó colonias de Ae. albopictus y Cx. pipiens. Las dosis subletales redujeron la supervivencia de los mosquitos, redujeron el tamaño de la población y brindaron una protección del 100% a los huéspedes humanos. Además, presentaron riesgos relativamente bajos para la salud humana y ambiental. El cuarto estudio exploró cómo las dosis subletales de repelentes espaciales podrían proteger a las personas de las picaduras de mosquitos al aire libre. Se realizaron dos experimentos de campo en Italia en un área de alta abundancia de Ae. albopictus usando un piretroide tipo I sintético, transflutrina, en forma de aerosol. Primero examinó los niveles de protección para los humanos y el segundo evaluó la mortalidad de los mosquitos. El porcentaje de protección para humanos se mantuvo alto (>80%) a las 5 h a pesar de la ausencia de mortalidad de mosquitos después de 1 h de aplicación. [cat] Els mosquits representen una amenaça important i creixent per a la salut humana degut al seu paper en la transmissió de malalties. Productes de protecció personal, com insecticides i repel·lents, poden disminuir la incidència de malalties i les molèsties relacionades amb els mosquits al reduir la freqüència de contacte entre ells i els seus hostes. Tot i això, la regulació de biocides s'ha tornat cada vegada més estricta pel fet de que el seu ús pot generar riscos toxicològics per a la salut humana i mediambiental. Aquesta tesi busca 1) validar noves metodologies de laboratori i de camp i 2) explorar paràmetres i/o enfocaments alternatius per avaluar insecticides i repel·lents. Es van dur a terme quatre estudis utilitzant Aedes albopictus (Skuse, 1894), Culex pipiens (Linnaeus, 1758) i voluntaris humans. El primer estudi va involucrar 16 participants per avaluar la taxa d'aterratge de mosquits en una àrea infestada per Ae. albopictus. Els resultats obtinguts es van comparar amb estudis de laboratori en 1) una cabina de 30 m3 on 9 voluntaris van ser exposats a diferent número de mosquits (15–50) i 2) una gàbia de 0,064 m3 que contenia 200 mosquits, test conegut com arm in cage (AIC). La taxa d'aterratge de mosquits més alta al camp va ser de 26,8 aterratges/min. L'assaig a la cabina va aconseguir una taxa similar utilitzant 15-20 mosquits i un temps d'exposició de 3 min. A l'AIC, la taxa va ser de 229 ± 48 aterratges/min. Aquest estudi és el primer a mesurar i comparar taxes d'aterratge a camp i laboratori amb Ae. albopictus. El segon estudi va explorar mètodes de laboratori alternatius per avaluar repel·lents de mosquits dús tòpic. Quatre laboratoris europeus van repetir les probes amb d'Ae albopictus i 30 participants van particicpar per configuració. Es van comparar resultats de protecció amb l'AIC convencional (àrees de braç exposades de 600 cm2) versus 1) l'AIC amb mànega (100 cm2) i volums de gàbia d'entre 0,040 i 0,064 m3. La densitat de mosquits va ser de 1 femella/840 cm3. 2) cabines d'entre 25–30 m3 amb 40 ± 5 mosquits. Es va emprar 15% N,N-dietil-m-toluamida en dues dosis: 1 i 0,5 g/600 cm2. Els dos nous mètodes van demostrar ser bones alternatives a l'AIC convencional produint temps de protecció reproduïbles a tots els laboratoris. El tercer estudi va avaluar en laboratori els efectes de dosis subletals d'insecticides utilitzades en tractaments espacials sobre l'estat físic dels mosquits; 2) protecció contra les picades de mosquits en humans; i 3) riscos toxicològics per a la salut humana i ambiental. Aquest treball va emprar un piretroide sintètic tipus I, praletrina, en tres dosis subletals (0,40 ± 0,01 mg/h, 0,80 ± 0,01 mg/hi 1,60 ± 0,01 mg/h) i va utilitzar colònies d'Ae. albopictus i Cx. pipiens. Les dosis subletals van reduir la supervivència dels mosquits, van reduir la mida de la població i van brindar una protecció del 100% als hostes humans. A més, van presentar riscos relativament baixos per a la salut humana i ambiental. El quart estudi va explorar com les dosis subletals de repel·lents espacials podrien protegir les persones de les picades de mosquits a l'aire lliure. Es van fer dos experiments de camp a Itàlia en una àrea d'alta abundància d' Ae. albopictus usant un piretroide sintètic, tipus I, transflutrina, en forma d'aerosol. Primer es va examinar els nivells de protecció per als humans i segon es va avaluar la mortalitat dels mosquits. El percentatge de protecció per a humans es va mantenir alt (>80%) a les 5 h malgrat l'absència de mortalitat de mosquits després d'una hora de l’ aplicació.