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Accurate identification of insect species is an indispensable and challenging requirement for every entomologist, particularly if the species is involved in disease outbreaks. The European MediLabSecure project designed an identification (ID) exercise available to any willing participant with the aim of assessing and improving knowledge in mosquito taxonomy. The exercise was based on high-definition photomicrographs of mosquitoes (26 adult females and 12 larvae) collected from the western Palaearctic. Sixty-five responses from Europe, North Africa and the Middle East were usable. The study demonstrated that the responders were better at identifying females (82% correct responses) than larvae (63%). When the responders reported that they were sure of the accuracy of their ID, the success rate of ID increased (92% for females and 88% for larvae). The top three tools used for ID were MosKeyTool (72% of responders), the ID key following Becker et al. [2010. Mosquitoes and their control, 2nd edn. Berlin: Springer] (38%), and the CD-ROM of Schaffner et al. [2001. Les moustiques d'Europe: logiciel d'identification et d'enseignement - The mosquitoes of Europe: an identification and training programme. Montpellier: IRD; EID] (32%), while other tools were used by less than 10% of responders. Responders reporting the identification of mosquitoes using the MosKeyTool were significantly better (80% correct responses) than non-MosKeyTool users (69%). Most responders (63%) used more than one ID tool. The feedback from responders in this study was positive, with the exercise being perceived as halfway between educational training and a fun quiz. It raised the importance of further expanding training in mosquito ID for better preparedness of mosquito surveillance and control programmes., (© N. Rahola et al., published by EDP Sciences, 2022.)

The mosquito species Aedes (Ochlerotatus) coluzzii Rioux, Guilvard & Pasteur, 1998 was distinguished from its sibling species Aedes detritus (Haliday, 1833) using an isoenzymatic method that required the destruction of the entire specimen, therefore no holotype was designated by the species authors. We aimed to designate a neotype for Ae. coluzzii from specimens collected from the type-locality and individually reared up to adult stage. Genomic DNA was extracted from pupal exuvia and ITS2 was sequenced, enabling verification of the identity of each specimen as Ae. coluzzii or Ae. detritus. Among the series of Ae. coluzzii, a male was designated as neotype and deposited in a collection. To our knowledge, this is the first time the type of a mosquito species is deposited thanks to its molecular identification from its pupal exuvia. The set of identified specimens allowed additional phylogenetic and morphologic studies., (© A. Berger et al., published by EDP Sciences, 2022.)

Control of invasive species relies partly on permanent surveillance at international points of entry. We report the exceptional trapping of one adult mosquito (Diptera: Culicidae) in the port of Marseille, France, in July 2018, during a routine survey conducted according to International Health Regulations. Morphological and molecular identification classified the specimen as a female Aedes (Stegomyia) aegypti (L.), vector of many arboviruses, absent from Europe and the Mediterranean rim since the 1950s. A world reference panel of approximately 23,000 genome-wide single nucleotide polymorphisms determined that the mosquito originated from Cameroon, west Africa. Cross-reference of this geographic location with boats traveling from Central Africa to Marseille during the trapping period suggests that the mosquito travelled within an identified merchant ship, a vehicles carrier connecting Douala, Cameroon to Marseille, France. This ship left Douala on June 25, 2018 and arrived 20 days later in Marseille on July 15. The mosquito was captured 350 m away from the dock. The interception of a propagule of an invasive species is a rare event that must be considered a priority to prevent its successful establishment., (© C. Jeannin et al., published by EDP Sciences, 2022.)

Background: In 2016, a field study was implemented in all Armenian provinces in order to update knowledge on the presence and distribution of both native and invasive mosquito species. Larvae and adult mosquitoes were sampled and identified on the basis of their morphology. Supplementary field surveys were performed in 2017-2018., Results: Between June 20 and July 12, 2016, 117 localities were visited. A total number of 197 sampling units were checked, of which 143 (73%) were positive for mosquitoes (with 1-6 species per sampling unit). A total number of 4157 mosquito specimens were identified to species or species complex level. Ten species represent first records for Armenia: Aedes albopictus, Ae. annulipes, Ae. cataphylla, Ae. cinereus/geminus (probably Ae. cinereus), Ae. flavescens, Anopheles plumbeus, Coquillettidia richiardii, Culex martinii, Cx. torrentium and Culiseta subochrea. The invasive species Ae. albopictus was recorded in a single locality (Bagratashen) at the border point with Georgia, along the main road Tbilisi-Yerevan. This species was further recorded in 2017 and 2018, demonstrating its establishment and spread in north Armenia. These surveys confirm the presence of vectors of malaria parasites (in particular An. sacharovi) and West Nile virus (Cx. pipiens)., Conclusion: The knowledge of the Armenian mosquito fauna is extended to a list of 28 species. The record of Aedes albopictus, an important potential vector of many arboviruses, has important implications for public health., (© L. Paronyan et al., published by EDP Sciences, 2020.)

An inventory of Phlebotomine sandflies was carried out in the Ankarana tsingy located in far northern Madagascar. A total of 723 sandflies were used for morphological, morphometric, and molecular studies (sequencing of partial cytochrome B (mtDNA) and partial 28S (rDNA)). Nine species were identified: Phlebotomus fertei, Sergentomyia anka, Se. sclerosiphon, Se. goodmani, two species of the genus Grassomyia, as well as three new species described herein: Se. volfi n. sp., Se. kaltenbachi n. sp., and Se. ozbeli n. sp. The recognition of these new species is strongly supported by molecular analyses. The first two of the new species could not be classified into any existing subgenus, therefore we proposed two new subgenera (Ranavalonomyia subg. nov., and Riouxomyia subg. nov.), with combinations as: Sergentomyia (Ranavalonomyia) volfi and Sergentomyia (Riouxomyia) kaltenbachi. Our study reveals important molecular variability in Se. anka, with the recognition of a population whose taxonomic status remains below that of species. Our research confirms the need to further study the specific diversity of Malagasy sandflies, which until the start of this millennium remained mostly unknown., (© A. Blavier et al., published by EDP Sciences, 2019.)

The Common bed bug, Cimex lectularius, had virtually disappeared from France in the 1950s; however, a worldwide resurgence of bed bugs (C. lectularius and C. hemipterus) has been observed since the 1990s. To document modern pest control activities for the management of bed bugs, a survey was conducted in metropolitan France among the two main categories of professionals regularly called upon to deal with the control of infestations: Municipal Health and Safety Services (MHSSs) and private Pest Management Companies (PMCs). These professionals responded to a questionnaire targeting their knowledge, attitude and practices related to the process for diagnosing a bed bug infestation and the processes taken to actually control an infestation. There were 68 responses received from MHSSs and 51 from the PMCs. The responses indicate that every single département (French administrative division) in metropolitan France has witnessed at least one intervention for bed bugs. Among the criteria considered sufficient to confirm a bed bug infestation, direct observation of bugs was the most commonly cited response. Faced with an infestation, most PMCs used a combination of non-chemical and chemical methods, and systematically performed two treatments. This survey is the first of professionals involved in bed bug control in metropolitan France and confirms the growing importance of bed bugs as a public health pest. Establishing a database to monitor this emerging pest would improve the understanding of the distribution of these insects, help guide educational requirements, identify research needs and assist in ensuring that the most appropriate control practices are undertaken., (© F. Jourdain et al., published by EDP Sciences, 2016.)

An identification key of the Phlebotomus in Madagascar is proposed as well as the description of the male and female Phlebotomus (Anaphlebotomus) vaomalalae n. sp. from Mikea Forest in the south-west of Madagascar. The assignation of this new species to the genus Phlebotomus is based on the presence of mesanepisternal setae. Its inclusion in the subgenus Anaphlebotomus is based on the males on the presence of four spines on the style, the lack of a coxite basal process and the existence of a bifurcated paramere. The female has cibarial and pharyngeal armature and spermathecal architecture similar to Phlebotomus fertei and Phlebotomus berentiensis, two other Malagasy species which belong to Anaphlebotomus. Male and female are held to belong to the same species because of their morphological characters, the homology (100%) of their partial cytochrome b mtDNA sequences and their capture in the same trap. P. vaomalalae n. sp. is a small species compared to the other Phlebotomus species of Madagascar. The cibarium of the male and the female of P. vaomalalae n. sp. is armed with teeth, like those of other Malagasy Phlebotomus. However, it differs in the arrangement and shape of the respective teeth and denticles. The male of P. vaomalalae n. sp. looks like that of P. fontenillei due to its tuft of coxal setae (lacking in P. berentiensis and P. fertei) but differs from this species by the location of this tuft. As P. fertei and P. berentiensis, there is no spermathecal common duct in P. vaomalalae n. sp., (© F.J. Randrianambinintsoa et al., Published by EDP Sciences 2013.)

Four mosquito species, including a new species of the genus Stegomyia, are reported from Mayotte in the western Indian Ocean. The most abundant species were Stegomyia aegypti and St. albopicta. Only one species of the St. simpsoni group was observed, St. bromeliae. The fourth species is Stegomyia pia Le Goff & Robert n. sp. of which the larva, pupa, male and female are here described. The larval stages of St. pia n. sp. are morphologically similar to St. aegypti but differ in the number of branches of the seta 1-X; the adult is morphologically distinct for a number of characters, for instance the scutal ornamentation. Stegomyia pia n. sp. is uncommon but not rare, and largely distributed across Mayotte. Its larval habitats are natural and diverse including rock pools, tree holes, and cut and severed bamboos. The biology of adults remains unknown, especially female biting behaviour. Both morphological characters and nucleotide sequences of the ITS2 and COI genes indicate that this species is best placed in the genus Stegomyia. Dichotomous keys to the four species of Mayotte Stegomyia are presented for adults and fourth-instar larvae. The potential vector role of these mosquitoes is hypothesised. This paper underlines advances in knowledge of the biodiversity in the French overseas departments and territories., (© G. Le Goff et al., published by EDP Sciences, 2013.)

No Phlebotomine sandflies had ever been reported in the Comoros Archipelago, including the three islands of the Republic of the Union of Comoros (Grande Comore, Mohéli and Anjouan) and the French oversea department of Mayotte. During three field surveys carried out in 2003, 2007 and 2011, we provided the first record of Phlebotomine sandflies in this area. A total of 85 specimens belonging to three species were caught: a new species S. (Vattieromyia) pessoni n. sp. (two females from Grande Comore), a new subspecies of Sergentomyia (Rondanomyia) goodmani (80 specimens from Grande Comore and one from Anjouan) and Grassomyia sp. (two females from Mohéli). The individualisation of these taxa was inferred both from morphological criteria and sequencing of a part of the cytochrome b of the mitochondrial DNA. These taxa are closely related to Malagasy sandflies.

The females of the moths Hylesia metabus have their abdomens covered by urticating hairs looking like micro-arrows and causing a puriginous dermatitis to humans known as "papillonite" in French Guiana and also called yellowtail moth dermatitis or Caripito itch. The densities of the moths show great seasonal and annual variations depending on mechanisms mostly unknown. When H. metabus infestations occur, numerous cases of dermatologic manifestations are reported from people living near the mangrove swamps where the moths are developing. One hundred years after the first "papillonite" epidemic reported from French Guiana in 1912, the data presented herein summarize the actual state of knowledge on H. metabus biology and ecology and on the lepidopterism. Some recommendations are proposed for the surveillance and warning systems of H. metabus infestations and to avoid contact with the moths. Research priorities are suggested to improve the control against this problem emerging between nuisance and public health.

The Hippoboscidae or "louse-flies" is a family of pupiparous Diptera, which in their adult stage are ectoparasites of mammals and birds. This paper presents a comprehensive review of Malagasy Hippoboscidae. In total, amongst the 213 species of this family known worldwide, 14 have been reported in Madagascar, among which six are considered as endemic to the Malagasy region. In addition, data are presented from a collection of 17 Hippoboscidae obtained from seven species of forest-dwelling birds in the "Parc National de Midongy Befotaka", southeastern Madagascar, in 2003. The flies in this collection belong to three different species: Icosta malagasii (one), Ornithoica podicipis (ten) and Ornithoctona laticomis (six). The two former species were previously only known from single specimens in museum collections; the later species is distributed across much of the Afrotropical region and the records presented herein are the first for Madagascar. All the seven bird species are new hosts for hippoboscids. We present the first description of the male of Icosta malagasii. An illustrated dichotomous determination key of the 14 Malagasy species, based on morphological criteria only, is presented.

Leucocytozoon coracinae sp. nov. is described from the avian family Campephagidae and Hepatozoon apodis sp. nov. from the Apodidae. The distribution of these parasites within their respective families is discussed.

Three new species of Phlebotomine sandflies belonging to the genus Sergentomyia França & Parrot are described from Madagascar: Sergentomyia sclerosiphon n. sp. S. namo n. sp. and S. anka n. sp. The taxa are created on the basis of the morphology of females. The males of S. sclerosiphon n. sp. and of S. anka n. sp. have been associated to the females according to the homologies of a fragment of the mtDNA cytochrome b sequences. The original morphology of the spermathecae and the sclerification of a part of the individual spermathecal ducts allow the creation of a new subgenus, Vattieromyia subg. nov., which includes these three new species.

Sergentomyia majungaensis, a new species of Phlebotomine sandfly, is described from Madagascar. The female is characterised by an unusual antennal formula (1/IV-V to VII; 2/VI to VIII-XV) and smooth and narrow spermathecae, with a common duct, whose shape is intermediate between Sergentomyia and Parrotomyia subgenera. The male has the same antennal formula than Grassomyia (1/IV-XV) but no hairs on the mesanepistern and a longer third antennal segment.

The presence of the filarial genus Litomosa in Malagasy bats is demonstrated by the finding of L. goodmani n. sp. from Miniopterus gleni and Litomosa sp. (male unknown) from M. manavi, both in the Special Reserve of Ankarana. These materials are compared to the 22 Litomosa species, including two Indian species originally placed in the genus Litomosoides, L. fotedari (Gupta and Trivedi, 1989) n. comb. and L. tewarii (Gupta and Trivedi, 1989) n. comb., and the new taxon L. seurati n. sp. (= L. beaucournui Bain, 1966 pro parte), type-host Rhinolophus ferrum-equinum, Algeria, distinguished by the narrow area rugosa and the female caudal extremity with two conspicuous points, instead of several small ones. The Malagasy material belongs to a group of species close to the type, L. filaria, which have a male area rugosa composed of cuticular bosses and microfilariae folded within the sheath, and which are parasitic in Vespertilionidae, Hipposideridae and Rhinolophidae from Africa and Europe. The two Malagasy species resemble L. seurati n. sp., L. beshkovi Jancev, 1971, L. chiropterum Ortlepp, 1932, L. adami Petit, 1980 and L. ottavianii Lagrange et Bettini, 1948, with the enlarged third segment of the buccal capsule. L. goodmani n. sp. is distinct with its small size and female caudal extremity with a single point, which is suppressed in old mature worms; the females of Litomosa sp. have two conical points. Relationships among Litomosa species appear to be dependent upon both the chiropteran host groups and the geographical region.

This work is the fourth related to species recently described from Madagascar. The authors describe Sergentomyia goodmani on females and males. The female has tubular spermathecae with internal spines. It has an aspect, in Canada balsam, of transversally striped spermatheca, without being completely segmented. The spermathecal ducts share a proximal common part. The pharynx is narrow. The cibarial armature is comb-like. Based on these characters, the authors consider that S. goodmani belongs to the subgenus Rondanomyia. They reinstate this subgenus and consider Neophlebotomus sensu Lewis, 1977 as invalid. Considering Grassomyia as a genus, this is the first record of Sergentomyia in Madagascar.

The male of Phlebotomus (Anaphlebotomus) fontenillei n. sp. is described from Namoroka area (Madagascar). Its belongs to the subgenus Anaphlebotomus: style with four spines, coxite without basal process and paramere with two branches. It shares with P. berentiensis an original and exclusive antennal formula: 2/III-XII which distinguishes them from P. fertei. P. fontenillei n. sp. differs mainly from P. berentiensis by about 40 setae in tuft on the ventral face of the coxite, the length of the genital ducts and the position of the spines on the style. Sequence of the second internal transcribed spacer (ITS2) of the ribosomal DNA (rDNA) is very informative: the male of P. fontenillei n. sp. cannot be linked to the female of P. huberti (male unknown) regarding the size of amplified DNA fragment (459 bp versus 600 respectively) and the high degree of variability. There are few differences (10 mutations) between the sequences of P. fontenillei n. sp. and P. berentiensis which are closely related species.

Mayotte is a French island located in the Comoros archipelago in the Indian Ocean. Due to the high level of resistance to chloroquine and sulfadoxine-pyrimethamine in this area, new therapeutic strategies are required. The aim was to assess and to document the efficacy of artemether-lumefantrine (AL) combination in four oral dosages. The follow-up was carried out during 21 days to monitor the antimalarial drug efficacy in an open trial in April-May, 2002. Results were obtained from 51 patients, aged from three to 46 years (12% less than five years). No case of therapeutic failure was observed. At day 2 after treatment, all the patients were apyretic and none of them had parasitaemia until day 21. This first therapeutic trial of the AL combination in the Indian Ocean sub-region shows that this association is safe, effective and rapid. AL should be an alternative treatment of uncomplicated malaria attacks in Comoros Archipelago, and will be of help to manage imported chloroquine-resistant falciparum malaria strains in Madagascar.

The female of Phlebotomus (Anaphlebotomus) fertei Depaquit, Léger & Robert, 2002 is described from Madagascar. The spermathecae have separated ducts, a body with an enlarged-sclerified dilatation and a deriviated large bladder with thin walls and long head. P. fertei female has the following characters: long antennal segments, pharyngeal armature with small teeth and cibarium with 15 to 30 denticles, and very long legs. Its remarkable spermatheca is closely related to that of P. berentiensis. The status of P. (Anaphlebotomus) berentiensis (Léger & Rodhain, 1978) is revised into this paper. The female is redescribed and the male is described for the first time. The latter has an unusual antennal formula (2/III-XII), a cibarium with four teeth and about 30 denticles, no tuft of setae on the coxite, four spines on the style, including a very long proximal one. Males and females were linked to each other based on morphological and molecular characteristics (second internal transcribed spacer of the ribosomal DNA and ND4 gene of the mitochondrial DNA). The inclusion of these taxa into the subgenus Anaphlebotomus Theodor, 1948 is exclusively based on male characters as listed by Theodor (style with four spines, no basal lobe on the coxite, paramere with two or three branches). The very heterogeneous characters of the females do not allow their use for the definition of this subgenus, which is probably not homogeneous.

The mosquitoes of the Anopheles gambiae complex have been characterised at specific and sub-specific levels in two islands of the Comoros archipelago: the island of Mayotte (French departmental collectivity) and the island of Grande Comore (Comoros Union). Results are similar in the two islands and are presented together. The species An. gambiae s.s. was observed alone (determination performed on 149 specimens by PCR product of IGS of rDNA). The molecular form observed alone was S, and corresponds in this geographic area to the chromosomal form Savanna (determination performed on 123 specimens by another PCR product of IGS of rDNA). The haplotype IB was observed alone (determination performed on ten specimens, by sequencing the ITS of rDNA, with special attention at the position 871 of ITS), as previously observed by other authors in East Africa. Finally, in Mayotte and Grande Comore the An. gambiae complex is only composed by An. gambiae s.s. from the molecular form S/type IB.

First record of Phlebotomine sandflies belonging to the genus Phlebotomus from Madagascar. Description of two new species: Phlebotomus (Anaphlebotomus) fertei n. sp. from three males and Phlebotomus (Anaphlebotomus) huberti n. sp. from two females. Their belonging to the subgenus Anaphlebotomus is supported by several characters. Male have four spines on the style, a coxite without basal tubercle, a paramere with two branches, one to three antero-inferior setae on the mesanepisternum. Female, closely related to the Asiatic species of the same subgenus, has a characteristic pharyngeal armature, about ten cibarial teeth, and annealing spermathecae with long ducts including a short basal common part. These two taxa differ by variation in the second internal transcribed spacer (ITS2) of the ribosomal DNA (rDNA). At the present time, the subgenus Anaphlebotomus includes six species (excluding P. fortunatarum from it), completing the known species from Africa (P. rodhaini and P. rousettus) and from Asia (P. stantoni and P. colabaensis).

Plasmodium falciparum gametocytaemia was studied in 266 Senegalese children (median 4 years, range 0.5-16) with uncomplicated malaria treated with chloroquine (CQ), amodiaquine (AQ) or sulfadoxine + pyrimethamine (SP). The proportion of resistant infections in vivo to these drugs was 44%, 16% and 7%, respectively. Gametocytes were counted by microscopy in thick smears on days 0, 4, 7 and 14 after treatment. There was a peak of gametocytaemia one week after treatment; on days 0, 7 and 14 the gametocyte prevalences were 35%, 73% and 63%, and the geometric means of gametocyte densities were 1.3, 12.5 and 5.6/microliter of blood. Three factors were found to influence gametocytaemia: treatment, efficacy of treatment, and duration of symptoms before treatment. Gametocyte prevalence and density significantly appeared higher in children treated with SP than with CQ, and higher with CQ than with AQ. Gametocyte prevalence and density were higher in resistant than in sensitive infections. The period between the appearance of the first clinical symptoms and treatment was positively and significantly linked to gametocyte prevalence and density on days 0 and 4. Early treatment with AQ, against sensitive infection, was followed by the lowest gametocytaemia. By contrast, treatment with SP against resistant infection was followed by the highest gametocytaemia. No clear relationship was observed between the density of asexual stages on day 0 and the gametocytaemia at any day between days 0 and 14. The epidemiological significance of post-therapeutic gametocytaemia and its possible role in the spread of resistant parasites are underlined. Solutions are proposed in order to avoid or reduce this gametocytaemia.

Anopheles arabiensis is the unique species of the An. gambiae complex observed in the wells dug by market-gardeners in the Dakar area. In order to relate the numbers of immature stages and emerging adults mosquitoes, population measurements were performed in eight wells in which An. arabiensis was the only mosquito species. Mean density of immature stages was measured using two sampling methods, the dipping with a tray by giving 50 dips in each well, and the quadrat with a frame on 2 or 3 m2 in each well. The absolute number of emergent adults was obtained by collecting mosquitoes under net-trap covering entirely each wells. The dipping method was quicker and more operational than quadrat method. Density estimations of larvae at stage I to IV did not significantly differed using dipping or quadrat methods. On the contrary, pupal density was underestimated when measured by dipping. Mosquito nets placed over wells increased significantly emergence rate of adults, thus measurement of emerging mosquitoes was possible only the first day following the net putting up. The total number of immature stages in each well was significantly correlated with the number of emergent mosquitoes. The mean number of mosquitoes emerging daily from one well corresponded to 5% of the total number of immature stages. Stage distribution for larvae I to IV and pupae, estimated by quadrat, was respectively 29%, 28%, 22%, 16% et 5% (total = 100%). Taking account the mean duration of various immature stages and the number of emerging mosquitoes by day, the equation of the survivorship curve from larval hatch (excluded) to emergence included was: y = 427.2-136.8 Log x. Therefore the mean mortality at immature stages was 80% i.e. an emerging rate of 20%. The results of this study, associated with those of previous ones, permit to evaluate the average productivity of malaria vectors in market-gardener wells in the Dakar area.

Literature on artificial membrane feeding has traditionally supported the notion that mosquitoes have to be enough old to present a high gorging rate and enough young to present a high surviving rate. In order to know the best mosquito age to perform a Plasmodium sp. experimental infection revealed by oocyst examination, Anopheles arabiensis of known ages were fed on baudruche membrane with fresh human blood thermostated at 37 degrees C. The response was evaluated in term of gorging after ten minutes in contact with the membrane feeder and, for engorged females, in term of survival eight days after the engorgement. Two strains of mosquitoes were used, one wild, collected at larval stages in the city of Dakar and the other, originating from the same place but reared in our insectary since three years. The two strains showed their highest gorging rate at 3-4 days after emergence (39.4% for the wild strain and 63.3% for the insectary strain). The survival rate of the wild strain was highest at 2-3-4 days after emergence (64.8%) and those of the insectary strain at four days (65.6%). In conclusion, the gorging mosquitoes would have to be aged of 3-4 days after emergence for the wild strain and of four days for the insectary strain in order to obtain eight days after the engorging the best output of fed and surviving mosquitoes.

In order to get an accurate measure of malaria transmission by mean of human bait attraction, three methods of catches for human-bail mosquitoes were compared in a Cameroonian village of high anopheline density. These three methods were 1) the classical human landing catches where the man was in the same time bait and catcher, 2) the single-nets which acted as a trap and 3) the double-nets where the outer net acted as a trap and the inner avoided mosquito bites. The anopheline densities per man with human landings were 1.6 time higher than those obtained with single-nets, these later being 4.7 times higher than those obtained with double-nets. In the three methods, the results were similar for the anophelines species catched and for their respective proportions. The samples of Anopheles nili and An. gambiae had comparative parity rates and sporozoitic indexes. From these results, in order to estimate the malaria transmission it can be envisaged to change the standard human-bait catch for the human-baited single bed-net catch; on the contrary the double-net have to be discarded because of their poor results.