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In Morocco, Culex pipiens plays a role in the high annoyance experienced by most urban cities, suburban and rural areas, especially since it was strongly suspected as the most likely vector in the transmission of West Nile virus epidemics that have hit Morocco in 1996. Chemical insecticides are generally the way in which they use the programs against harmful mosquitoes and disease vectors. However, the repeated and excessive use of these products regularly led to the emergence of the phenomenon of insect resistance. At the center of Morocco, information on the susceptibility or resistance to insecticides in mosquitoes (larvae and adults) vectors of diseases or pests, are almost nonexistent. This article reports the results of studies conducted between 2007 and 2010 with sensitivity tests WHO on larvae local populations of Culex pipiens collected in three lodging in the city of Fez, towards the insecticide mostly used by hygienic services: temephos. Five concentrations of insecticide (0.0025 mg/l, 0.005 mg/l, 0.0125 mg/l, 0.025 mg/l, 0.0625 mg/l) in addition to control, were used to determine the LC50 and LC 90 of Culex pipiens species towards temephos. Sensitivity tests were carried out at the entomology unit and monitoring of insect sensitivity towards insecticides installed at the Regional Diagnostic Laboratory Epidemiological and Environmental Hygiene (LRDEHM), Fez, under the Regional Directorate of Health in Fes Boulemane Region. The LC50 and LC90, concentrations corresponding to 50 and 90% mortality were determined graphically, by the linear relationship between the decimal logarithm of insecticide concentrations (x-axis) and the percentage of mortality transformed into probit values (ordinate) on logarithmic gausso paper. Resistance rates were determined on the basis of the sensitivity of a reference strain (S-Lab). The bioassay results affirmed the presence of resistance in larvae Culex pipiens towards temephos and that this species has also equally developed resistance levels similar and comparable in the three lodging studied, resistance rates recorded varying between 12.17 and 14.34. Facing such a situation, the surveillance of susceptibility of mosquitoes to insecticides used in mosquito control and anti-malarial fight has become imperative. This would undoubtedly allow a good management of the products available and consequently to adopt suitable measures for the best management of this resistance which must be an integral part of any program of vector control.

This survey, conducted from July 2003 to June 2004, was to assess the variation of the level of sensitivity of Cx. quinquefasciatus to the pyrethroids recommended for the impregnation of the mosquito nets, in the township of Yopougon situated in the Northwest of Abidjan city in relation with the bed of a drainage channel of sewage water that passes through the township from the north to the south. Five districts have been chosen along this channel according to the level of urbanization, for the withdrawal of the pre-imaginal populations of Cx. quinquefasciatus in collections of stagnant sewage water of this township. The female Cx. quinquefasciatus aged three to five days from the exits of the insectarium have been exposed to papers impregnated with deltamethrin 0.05%, permethrin 1% and DDT 4% in view of the diagnosis of a possible resistance of these populations to these insecticides. The populations of Cx. quinquefasciatus proved to be resistant to the three insecticides used, in four districts. On the other hand, the population of Cx. quinquefasciatus from the district "Zone industrielle," situated upstream of the channel, proved to be sensitive to permethrin 1%, and a drastic decrease of sensitivity of the same mosquito has been observed with deltamethrin 0.05% and DDT 4%.

This is the first description of Ae. albopictus in Grande Glorieuse and Juan de Nova, which are two isolated French islands of the Mozambique Channel. The recent introduction of this species is underlined by its absence in the inventories realised between 2000 and 2003. The last severe arbovirus epidemic of chikungunya (2005-2006), vectored by Ae. albopictus, which occurred in the area of the Indian Ocean emphasized the epidemiological role of this vector. So that, notifying its presence might help to target potential exotic arboviruses that could be introduced into the island. Furthermore this study allowed us to update the culicidae inventory, not only with this species, but also with the first observation of Culex sitiens in Europa and the confirmation of Ae. dufouri on this island. In order to determine the different species at the adult and/or at the larval stage, the authors propose keys of identification for mosquito species of the Eparse islands. All the described species on these islands are allochthonous species and some are being a nuisance. Sanitary recommendations together with biological and mechanical controls are proposed in order to reduce the nuisance and to prevent from any new introduction on these islands.

In April 2008, Abidjan was again faced with another case of yellow fever after the epidemic of 2001 causing mass immunization campaign. In order to evaluate the extent of amaril virus circulation and the risk for local people, an entomological investigation was carried out by the Ministry of Health and Public Hygiene of Côte d'Ivoire. At "Entent" area of Treichville, Breteau index was estimated at 34, recipient index at 20% and house index at 25%. Those indexes were respectively 53, 21 and 31% at "Vridi canal" of Port Bouet. In the both neighborhood, Aedes aegypti accounted for more than 80% of mosquitoes caught and more than 90% of mosquitoes adults obtained from larval breeding. This new situation of epidemic risk could be explained by several factors including the reception of 70% of forced migration people caused by the crisis in the country occurred in 2002, the probable drop of preventive immunization, the environment deterioration creating of more breeding sites of Ae. aegypti.

Culex pipiens gonotrophic cycle has been studied, for the first time in Morocco, under experimental conditions. Its average duration was estimated at 5.54 +/- 1.73 days.

The islets of Europa, Juan-de-Nova and Grande-Glorieuse are French territories isolated in the Mozambique Channel (Indian Ocean) which have remained relatively preserved from anthropization all along their history These three islets have been classified entire nature reserves from 1975 and are today inhabited only by a permanent military detachment of about fifteen men even if they occasionally greet technical and scientific staff. Sanitary and environmental issues brought about assessment of the present culicid fauna. The authors propose a synthesis of the culicid knowledge from the islets and make an inventory of new species. The role played by humans in importation of culicids is discussed as well as sanitary consequences of their adaptation to environment

Three surveys related to the knowledge, attitude and practices of populations towards mosquitoes were conducted in Côte d'Ivoire. The first survey was undertaken in June 1994 in the city of Bouaké and the other two respectively in January 1996 and in June 1999 in the village of Kafiné. The surveys have revealed that whatever the environment, nuisance due to mosquitoes constitutes a great concern for the population of the villages. The majority of people interviewed in urban (94%), peri-urban (68%) zones and in Kafiné (94%) associates mosquito with malaria against 18% only in Kabolo. Furthermore, these surveys have allowed the inventory of methods of controlling mosquito currently used by the communities in both urban and rural areas. Generally mosquito coils as well as insect sprays are currently used because of their cheapness and their availability on the local market. in Bouaké, insect sprays (97% to 99%) are used as much as mosquito coils (87% to 98%). However, in Kafiné and Kabolo, insect sprays are only used by respectively 76% and 69% and the mosquito coils by respectively 68% and 71%. In urban zones, the insect sprays are more common than mosquito coils. On the contrary mosquito coils are currently used in villages due to their low price (40 to 50 FCFA) and their constant availability on the local market. Furthermore, local plants characterized by a repulsive essence are known by 48% and 75% of people interviewed respectively in the urban and peri-urban area of the city of Bouak6, by 74 % of the population of Kafiné and 73% of people living in Kabolo. In the last village 57% of people who were interviewed do not use any means of orotection due to financial reason; only 14% use mosquito coils and 20% use local plants with a repulsive essence. Mosquito net is known by the majority of people interviewed (82 - 98%) as an excellent means of orotection against mosquito bites. However only 27%, 13%, 26% and 5% of people respectively living in the urban and peri-urban areas of Bouaké and in the villages of Kafiné and Kabolo own their mosquito net. Its cost is the main reason for not using it as mentionned by 25% of people interviewed in the urban neighborhood, by 48% in the peri-urban areas, respectively 46% and 89% in the villages of Kafiné and Kabolo. Although its effectiveness has been proved by the communities, mosquito net still remains less common. Its price is relatively high (3500 - 5000 FCFA). It is not constantly available on the local market. Other socio-cultural factors such as local beliefs and taboos hinder the use of mosquito nets by the communities.

In the framework of a pluri-institutional research project, led in Abidjan and aimed at defining measures to fight against mosquitoes in Abidjan area, a test to struggle for C. quinquefasciatus larvae was carried out in 1990. This test was conducted in Koumassi, which is one of Abidjan district, in which environmental conditions are very favourable for developing C. quinquefasciatus non-adult stages. The test consisted essentially in spreading a Bacillus sphaericus waterish solution (dose: 10 g.m-2) in previously cleaned gutters. The efficiency of the fight test was essentially assessed through: -the size of C. quinquefasciatus non-adult stages populations according to their development stage (egg, larva, nymph); -variations of both, C. quinquefasciatus females aggressive density and their physiological age. The gutters cleaning did not reduce significantly C. quinquefasciatus non-adult stages populations. On the other hand, the effectiveness of B. sphaericus was convincing. Its effects were tested to last for four weeks. The results were confirmed by the observations made on C. quinquefasciatus adult populations.

In October 1988-January 1989, as a part of a malaria and filariasis control programme in Federal Islamic Republic of Comoros an entomological survey was carried out in 19 rural and urban localities of Grande Comore. Anjouan and Moheli Islands. The potential breeding places were examined and pyrethrum spray catches were made to evaluate the indoor resting densities of mosquitos. A total of 14.578 adult mosquitos potential vectors of filariasis was collected: 94.5% Culex quinquefasciatus, 3.5% Anopheles gambiae s. str. 1.9% A. funestus and 0.1% other anopheline species. A. funestus, uniformly spread in Moheli, was present only in the south-west coast of Anjouan and absent in Grande Comore. A. gambiae and Cx quinquefasciatus were present in Grande Comore. A. gambiae and Cx quinquefasciatus were present in the three islands with different densities in the villages. Only Cx quinquefasciatus specimens la maximum of 150 for each locality) were dissected to search filaria larvae being the Anopheles specimens used to evaluate the malaria transmission. The global infection rate (9.4%) and the infectivity rate (0.9%) observed in Cx quinquefasciatus are higher than indices reported in previous surveys. All the larvae in the third development instar (L3) were identified as Wuchereria bancrofti. The results suggest that in FIR of Comoros W. bancrofti is well adopted to local Cx quinquefasciatus population. Because of the presence of high mosquito density this species plays a prominent role in the transmission of lymphatic filariasis in that area. The high transmission levels calls for the implementation of a specific control program.

The presence of an anautogenous and stenogamic population of Culex pipiens pipiens in Languedoc, France, is reported. The anautogeny was confirmed through 10 generations. A Callot morphogram corresponded to the anautogenous form. These results raise again the question of the type of relationships, genetic or ecological, of the characters classically associated with autogeny.

Culex bitaeniorhynchus, reported from New Caledonia after a single collection of larvae in Noumea in 1952, has been found in two other localities, on the south-west and on the north-east coasts. The morphological features show some differences between the local population and the forms from the Oriental Region. Adults have been caught during the hot and rainy season, by light traps mainly. The females have been very rarely collected on human bait. Though found naturally infected by dengue 4 virus, that species is not likely to have an epidemiological importance in New Caledonia. It seems doubtful that it has been imported recently.

The author gives the results of an entomological survey in neo-caledonian archipelago (New Caledonia and Loyalty Islands), november-december 1972. Concerning the distribution and the abundance of Aedes aegypti, the local dengue vector, this study shows the presence of this culicid not only in Noumea, but also all along the western developped coast of New Caledonia, and in Ouvea Island. This constitutes a great risk of outbreak extension from Noumea if a dengue virus is again imported there.