Biology of two larval morphological phenotypes of Aedes aegypti in Abidjan, Côte d'Ivoire.

Since 2008, several outbreaks of yellow fever and dengue occurred in Abidjan, the economic capital of Côte d'Ivoire. A better knowledge of the biology of Aedes aegypti populations, the main vector of yellow fever and dengue viruses, is necessary to tailor vector control strategies implemented in the city. This study was designed to determine some biological parameters, occurring during the life cycle of two morphological phenotypes of Ae. aegypti larvae. Mosquitoes were sampled in a suburb of Abidjan (Treichville) using the WHO layer-traps technique. Biological parameters were studied in laboratory under standard conditions of temperature (27°C ± 2°C) and relative humidity (80% ± 10%). Our results indicated that the mean eggs laid by females from 'brown larvae' (BL) (85.95, 95% confidence interval (CI 95%) 78.87-93.02) was higher than those from 'white larvae' (WL) (64.40%, CI 95% 55.27-73.54). The gonotrophic cycle was 3 and 4 days in females from BL and WL, respectively. The overall yield of breeding mosquitoes from BL (63.88%, CI 95% 62.61-65.14) was higher compared with those of mosquitoes from WL (59.73%, CI 95% 58.35-61.12). The sex ratio (male/female) was 0.95 and 1.68 in Ae. aegypti populations from BL and WL, respectively. Females from BL lived slightly longer than those from WL (t = -2.332; P = 0.021). This study shows that Ae. Aegypti populations from BL and WL present different biological parameters during their life cycle. This could have an implication on their ability to transmit human disease viruses such as dengue and yellow fever. Further molecular studies are needed to determine genetic divergence between these Ae. aegypti populations.

Qualite de vie des eleves abidjanais : cas des eleves du lycee moderne Harris d'Adjame

"Introduction. En Cote d'Ivoire; la sante des eleves fait partie de la politique sanitaire; a travers le Programme National de Sante Scolaire et Universitaire (PNSSU). Cette etude avait pour objectif de decrire la qualite de vie des eleves d'un lycee de la ville d'Abidjan pour la promotion de la sante en milieu scolaire. Population et methode. Il s'agissait d'une enquete transversale a visee descriptive; realisee du 05 au 30 janvier 2008 au Lycee Moderne Nanguy Abrogoua (Abidjan). Un echantillonnage aleatoire systematique a permis de selectionner 770 eleves qui ont fait l'objet d'interview individuelle a l'aide d'un questionnaire standard. Resultats. Les eleves en majorite de sexe masculin (54;1%) avaient un age moyen de 16;5 ans avec un ecart type de 5;7 ans. Plus de la moitie des eleves (58;5%) residaient hors de la commune d'implantation du lycee. Plus du tiers des eleves (34%) affirmaient que les parents ne disposaient pas d'assez de moyens pour subvenir aux besoins de la famille. Par consequent; 22;7% faisaient de "" petits boulots "" pour financer leur etude et 25;6% affirmaient ne pas manger a leur faim. La majorite des eleves etait souvent angoissee (64;4%); deprimee (73;3%) et se sentait souvent mal dans la peau (68%). Ceux qui avaient des troubles du sommeil representaient 42;5% des enquetes. Pres de la moitie des eleves etait inquiete de leur sante (49;2%) et achetait les medicaments de rue pour se soigner (48;6%). En cas de probleme de sante; plus de la moitie (54;8%) ne frequentaient pas les services de sante scolaire par manque d'information (36;5%) ou par insatisfaction des soins recus dans ces services (24%). Parmi les eleves; 42;3% etaient sexuellement actifs et la sexualite constituait une source d'inquietude ou de preoccupation (48;9%) a cause du VIH-Sida (76;9%); des grossesses non desirees (54;4%). De plus; des comportements a risque tels que la consommation des medicaments vendu dans les rues (48;9%); la pratique du "" boro d'enjaillement (jeux perilleux consistant a s'adonner a des acrobaties et autres pas de danse sur le toit d'un bus en mouvement) "" (1;7%) et l'avortement (10;7%) etaient observes chez les eleves. Conclusion. La prise en compte de ces resultats pourrait contribuer a l'adoption de strategie visant a l'amelioration de la qualite de vie ou du bien etre des eleves; condition necessaire a un bon rendement scolaire. "

[Description of sexual practices of women who have sex with other women to HIV / AIDS in Abidjan (Côte d'Ivoire)]. / Description des pratiques sexuelles des femmes ayant des rapports sexuels avec d'autres femmes face au VIH/sida à Abidjan (Côte d'Ivoire).

The response to HIV must be based on all situations of risk and vulnerability related to sexual behavior. Sexual practices of women who have sex with other women to HIV described in his study come within this framework. This transversal and descriptive study on the sexual practices of 150 women who have sex with other women to HIV was conducted from July to September 2010 in Abidjan. Mean age of the respondents was 26.6 years. Among them, 21.3% was illiterate, 41.4% had no earned income and 57.3% was Christians. At the time of data collection, the majority (70.7%) did not know their HIV status. The analysis of sexual practices has found 13.3% of lesbians, bisexual, 36% and 50.7% of women who say they are lesbian even if they have had sex with men. Women who have sex with other women had sexual risk behavior. It was mostly the non-systematic use of the condom during sexual relation (60%). Among the 26.7% of respondents who had lesbian practices with penetration, 40% took no precaution to prevent HIV and other sexually transmitted infections. Taking into account these results could help to develop specific strategies to promote responsible sexual practices among women who have sex with other women.

[Entomological evaluation of the risk of urban outbreak of yellow fever in 2008 in Abidjan, Côte d'Ivoire]. / Évaluation entomologique du risque d'épidémie urbaine de fièvre jaune survenue en 2008 dans le district d'Abidjan, Côte d'Ivoire.

In April 2008, seven years after the outbreak of 2001, Abidjan faced another epidemic of yellow fever. Three weeks after the case detected in the commune of Treichville at 28(th) of April 2008, two other cases were notified, the first one in Port-Bouet and the second one in Cocody located respectively in the south and north of the city of Abidjan. In order to determine a large-scale risk of urban yellow fever epidemic, epidemiological and entomological investigations were conducted by the Ministry of Health and Public Hygiene of Cote d'Ivoire with the support of the Global Outbreak Alert and Response Network. Entomological investigations revealed the predominance of Aedes ægypti, urban vector of yellow fever in neighborhood visited with larval density indices between 2 and 5, indicating the existence of a sufficient density of the vector for cause an explosion of the epidemic. In fact, the massive influx of people from inside cities towards Abidjan caused by the socio-political crisis occurred in the country in 2002, the deterioration of environment with the creation of more breeding sites of Ae. ægypti as corollary and the circulation of the virus at mosquito level were many factors favorable to the yellow fever outbreak in Abidjan city.

[Culex quinquefasciatus sensitivity to insecticides in relation to the urbanization level and sewage water in Yopougon, a township of Abidjan (Côte-d'Ivoire)]. / Sensibilité de Culex quinquefasciatus aux pyréthrinoïdes en relation avec le niveau d'urbanisation et l'évacuation des eaux usées dans la commune de Yopougon à Abidjan (Côte-d'Ivoire).

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%.

[Resistance of Anopheles gambiae s.l. to pyrethroids and DDT at Tiassalékro, an irrigated rice-growing village in the southern forest of Ivory Coast]. / Résistance d'Anopheles gambiae s.l. aux pyréthrinoïdes et au DDT à Tiassalékro, village de riziculture irriguée en zone sud forestière de Côte-d'Ivoire.

An assessment of the sensitivity of Anopheles gambiae s.l.to three pyrethroids (alphacypermethrin, permethrin, deltamethrin) and DDT has been carried out with a laboratory strain (Kisumu reference sensitive strain) and a wild strain (Tiassalékro strain) using larvae from an irrigated rice-growing area of Tiassalékro, located in the southern forest of Ivory Coast. The sensitivity tests were performed according to the standard WHO cylinder tests with adult female A. gambiae s.l. aged 2 to 4 days. The results showed that the strain of Tiassalékro is resistant to the three tested pyrethroids and DDT. The molecular forms M and S were identified, with a predominance of M form. The resistance mechanism involved is the Kdr mutation. In this region, control measures against malaria vectors by using bed nets impregnated with these insecticides or household sprays could be compromised.

[Micronecta sp (Corixidae) and Diplonychus sp (Belostomatidae), two aquatic Hemiptera hosts and/or potential vectors of Mycobacterium ulcerans (pathogenic agent of Buruli ulcer) in Cote d'Ivoire]. / Micronecta sp (Corixidae) et Diplonychus sp (Belostomatidae), deux hémiptères aquatiques hôtes et/ou vecteurs potentiels de Mycobacterium ulcerans agent pathogène de l'ulcère de Buruli en Côte d'Lvoire.

Buruli ulcer is currently a major public health problem in Côte d'Ivoire. It is a neglected tropical disease closely associated with aquatic environments. Aquatic insects of the Hemiptera order have been implicated in human transmission of Mycobacterium ulcerans, the pathogenic agent of Buruli ulcer. The purpose of this preliminary study using the polymerase chain reaction (PCR) method was to evaluate aquatic insects in Sokrogbo, a village in the Tiassalé sanitary district where Buruli ulcer is endemic. Findings identified two water bugs hosting Mycobacterium ulcerans, i.e., one of the Micronecta genus in the Corixidae family and another of the Diplonychus genus in the Belostomatidae family. The PCR technique used revealed the molecular signatures of M. ulcerans in tissue from these two insects. Based on these findings, these two water bugs can be considered as potential hosts and/or vectors of M. ulcerans in the study zone. Unlike Diplonychus sp., this is the first report to describe Micronecta sp as a host of M. ulcerans. Further investigation will be needed to assess the role of these two water bugs in human transmission of M. ulcerans in Côte d'Ivoire.

[Entomological investigations conducted around ten cases of yellow fever in 2009 in the Denguélé sanitary region, Côte-d'Ivoire]. / Investigations entomologiques menées autour de dix cas de fièvre jaune survenus en 2009 dans la région sanitaire du Denguélé, Côte-d'Ivoire.

In November 2009, ten suspicious cases of yellow fever, including six deaths, were notified in the region of Denguélé, in the northwest of Côte-d'Ivoire. In order to evaluate the extent of yellow fever virus circulation and the risk for local people, a mission of entomological investigation was carried out by the Ministry of Health and Public Hygiene of Côte-d'Ivoire. Entomological investigations were conducted in the villages of confirmed cases (Banakoro and Tron-Touba) and the centers of consultation and hospitalization of cases during illness. Breteau index and recipient index were quasi nil. Aedes aegypti was absent among the captured mosquitoes. On the other hand, Aedes luteocephalus and Aedes opok were present at Banakoro and Tron-Touba with respective average biting rates of 0.8 and 0.6 bite/man/twilight. This situation of epidemic in the northwest of Côte-d'Ivoire could be explained by the deterioration of Denguélé region's health system which is a consequence of the war started in the country in 2002 and which has lowered the immunity of the population.

[Specific diversity and culicidian nuisance in the villages of N'gatty and Allaba in laguna area of Ivory Coast]. / Diversité spécifique et nuisance culicidienne dans les villages de N'gatty et d'Allaba en milieu côtier lagunaire de Côte-d'Ivoire.

Entomological surveys were undertaken between June and December 2006 in N'gatty and Allaba. These villages are located in southern Ivory Coast in a laguna area in Dabou department. In these villages, there are large swampy areas, which have caused the multiplication of anthropophilic Culicidae. Mosquitoes have been collected at preimaginal stage at the time of the larval prospecting and at adult stage through human landing catch. Larval collections have been made using the classic method of "dipping". Larvae have been identified to the genus level. Then, they have been bred in the laboratory to identify adults. Adults collection has been made once a month during three consecutive nights by human landing catch inside houses. Adults have been identified to the specific level. Eight genera of mosquitoes have been collected in these two villages: Aedes, Anopheles, Coquillettidia, Culex, Eretmapodites, Mansonia, Toxorhynchites and Uranotaenia. Twenty-four species have been listed during this stu y. The genus Mansonia is the most predominant with 86% (N = 15,811) and 80% (N = 1,385), respectively, in N'gatty and Allaba. The average biting rate per day varies between N'gatty and Allaba. It is estimated to 308 bites per human per night (b/h/n) in N'gatty and 72 b/h/n in Allaba. In these villages, mosquito nuisance is mainly due to Mansonia with 264 b/h/n and 58 b/h/n, respectively, in N'gatty and Allaba. However, Anopheles gambiae s.l. average rate was 12 b/h/n in N'gatty and 2 b/h/n in Allaba.

[Entomological investigation following the re-emergence of yellow fever in 2008 in Abidjan area (Côte d'Ivoire)]. / Investigation entomologique à la suite de la réémergence de la fièvre jaune en 2008 à Abidjan (Côte d'Ivoire).

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.

[Malaria transmission in Tiassalékro, a irrigated rice growing village situated in the South forest area of Côte d'Ivoire]. / Transmission du paludisme a Tiassalèkro, village de riziculture irriguèe situé en zone sud forestière de Côte d'Ivoire.

A longitudinal entomological study was carried out from January to June 2007 in the rice-growing area of Tiassaékro, a village located in the forest, South of Côte d'Ivoire. The study was based on samples of mosquitoes caught on human volunteers indoors and outdoors. During the 6 months of the study 29481 female mosquitoes were caught. The average biting rate was 272.9 bites per man per night (b/m/n). An. gambiae was the most predominant with 79.1% of mosquitoes caught. The average biting rate of An. gambiae was of 216 b/m/n. The biting activity of this species was noticed between 8 p.m. and 6 a.m. The estimated average sporozoite index was 0.32% (n = 3423 dissected). The inoculation rate was 0.69 ib/m/n with the highest rate (1.99 ib//n) recorded in April. The entomological parameters of the transmission are influenced by the different stages of rice growing.

[Epidemiologic study on patrons of traditional drink establishments (Bandjidromes) in Abidjan, Ivory Coast and surrounding areas]. / Enquête epidémiologique a propos des usagers des débits de boissons traditionnelles (Bandjidromes d'Abidjan et de sa banlieue).

This transverse descriptive study was conducted over a three-month period from January 10 to April 10, 2003. Findings demonstrated a clear profile of 120 patrons of traditional drinking establishments called n the city of Abidjan and surrounding areas in the Ivory Coast. All subjects interrogated were male. Mean age was 31.1 years. Almost all subjects interrogated (99.2%) were of Ivory Coast nationality. The main ethnic group was Akan (86.7%) from Baoulé (60%). More than a third (35.9%) of subjects interviewed were unemployed. Most (62.5%) were single. All subjects interrogated stated that they attended "bandjidromes" to drink palm wine although other alcoholic beverages were served. However only 9.2% of subjects drank only palm wine. The euphoric effect of alcohol and friendly atmosphere of the drinking establishment were the main reasons for attendance (53.3%). Most persons interrogated (63.3%) had been consuming alcohol for more than 10 years. More than half (55%) spent less than three hours a day drinking alcoholic beverages. Daily consumption of palm wine ranged from two to four liters for most atrons (76.7%). Only 2.5% (3/120) presented neuropsychiatric disturbances. These results could be useful in the fight against alcoholism.

Combination therapy using aspirin-enhanced photodynamic selective drug delivery.

In photodynamic therapy (PDT), excitation of a drug by light leads to a cascade of biochemical processes that can cause closure of blood vessels. It has been observed clinically that significant short-term leakage from the irradiated vasculature can occur prior to vessel closure and blood flow stasis. In this paper we demonstrate in a chicken embryo model that this leakage can be significantly enhanced by the presence of the cyclo-oxygenase inhibitor, aspirin. We also observe that following this aspirin-enhanced leakage, blood vessels close as effectively as after PDT in the absence of aspirin. Consequently we propose that this PDT-induced aspirin-enhanced leakage can be used to locally deliver a drug for combination therapy. This is then demonstrated in the chicken embryo using Visudyne as a PDT agent in combination with aspirin and fluorescein isothiocyanate dextran 10 kDa as leakage indicator. The latter represents a hypothetical drug to be delivered in various kinds of combination therapy. Two examples of this procedure would be the photodynamic treatment of choroidal neovasculature associated with exudative age-related macular degeneracy (AMD) where local delivery of an anti-angiogenic or an anti-inflammatory drug has been shown to be effective, or PDT of cancer where local dosing of a chemotherapeutic drug may well increase the treatment efficacy.

[Acceptability of HIV screening in patients suffering from sexually transmitted infections at the antiveneral center of Abidjan, Côte-d'Ivoire]. / Acceptabilité du dépistage du VIH chez les patients atteints d'infections sexuellement transmissibles au dispensaire antivénérien d'Adjamé, Côte-d'Ivoire.

The systematic screening in high risk groups can be an efficient way to struggle against HIV/AIDS. We have conducted a transversal descriptive study in patients suffering from STI and who had consulted the antiveneral dispensary of the Institut National de Santé Publique (Abidjan) from 1st September 2002 to 31st October 2002. The aim was to identify the acceptability of the HIV screening test. During this inquiry, 167 patients were recruited. This study permits to confirm the young age of the population with a male predominance in patients having sexual transmitted infections. So, 70.1% have accepted to do this test. However, 23.4% of patients recruited had really done the HIV test. Among those who have accepted to do the test, 28.2% were infected.