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Background: Malarial infection in non immune pregnant women is a major risk factor for pregnancy failure. However in malaria endemic areas, intermittent preventive treatment (IPTp) have been adopted to prevent malaria in pregnancy women since 2003 in Senegal. The impact of IPT on the development of immunity is not very well documented. We conducted a prospective study at the Roi-Baudouin maternity hospital of Guediawaye in Senegal to assess IL10, IL12, TNFα and IFNγ cytokines production in pregnant women under IPTp. Cytokines were analyzed in 82 sera at inclusion and delivery. P. falciparum HRP2 antigen was detected in 17% of women included by rapid diagnostic test (RDT). At inclusion the mean of IL10 response was higher in P. falciparum negative women (8 UA) compare to RDT-positive women (7 UA) p=0.069 while in delivery the opposite was found p=0.014. Low production of inflammatory cytokines IL12, IFNγ and TNFα was noted in both groups. Between inclusion and delivery, a significant increase of IL-10 production was noted while a decrease of IFNγ and TNFα cytokine was noted. Thus, IL12 and IFNγ responses may synergistically associate as malaria immune response during pregnancy.

This is a prospective, descriptive and analytic study conducted from July 2011 to September 2011 at the Children National Hospital Albert Royer of Dakar and at the Vélingara Health District. It was focused on children under 15 without reference to HIV status. For each child, a sample of stool was examined by the Ziehl-Neelsen modified staining and by ELISA using the "Cryptosporidium Antigen Detection Microwell ELISA kit" designed to detect Cryptosporidium spp antigens. The aim of our study was to determine the prevalence of cryptosporidiosis in rural and hospital areas and to measure the performance of the ELISA kit that we used. Out of the 375 stool examinations performed with the Ziehl-Neelsen modified staining, 17 had revealed the presence of Cryptosporidium spp (4.53%). The prevalence in rural areas was 2% while the hospital prevalence was 7.4%, of which 1.8% (1/57) were from urban areas and 9.8% (12/122) from suburban areas. No positive case was observed in children over 10 years. By ELISA, 23 positives cases were reported corresponding to a prevalence of 6.13% (1.8% in children living in urban areas, 13.1% in children from suburban areas and 3%living in rural areas).The correlation of this assay with the Ziehl-Neelsen modified staining, considered as the reference method, found that this assay had a sensitivity of 58.82% and a high specificity reaching 96.37%. The positive predictive value (PPV) was 43.4% while the negative predictive value was 98%. Cryptosporidiosis is a significant cause of parasitic infection among children in Senegal. Antigen detection of Cryptosporidium spp by ELISA in stool can be a complementary tool in the diagnosis of cryptosporidiosis.

The impact of intermittent presumptive treatment (IPT) on the immunity of pregnant women in Senegal is still not very well known. We conducted a prospective study at the Roi-Baudouin maternity of Guediawaye in Senegal to assess IgG antibodies production against MSP1, GLURP and DBL5 in pregnant women under IPT. Blood samples were collected from the participating women at inclusion and delivery. Samples were analyzed after centrifugation for the detection of IgG antibodies in sera by Elisa. Informed consent was given by each study participant prior to their inclusion. A total of 101 eligible women aged from 18 to 44 were included in this study. Multigravidae women represented 70.3% of the study population, whereas primigravidae accounted for 29.7%. The IgG level decreased slightly from inclusion to delivery for the women with regard to anti-MSP1 (83.1at inclusion versus 79.5 at delivery, p = 0.52) as well as anti-GLURP-R2 (84.1 at inclusion versus 75.9 at delivery, p = 0.16). After adjustment for number of pregnancies, there was a significant decrease in the production of anti-VAR2CSA between inclusion and delivery (p < 0.05). By reducing the incidence of malaria during pregnancy, IPT reduced the acquisition of placental parasites antibodies suppressors which could delay the development of protective immunity against malaria. The application of IPT in pregnant women would thus be more appropriate in hypoendemic areas where malaria exposure is lower.

This retrospective study was carried out to describe the epidemiological, clinical and aetiological aspects of clear-fluid meningitis among HIV-positive patients admitted at the Infectious Diseases Clinic in Fann Teaching Hospital in Dakar Data were collected for analysis from patients files recorded from January 1, 2001 to December 31, 2003. Forty-six cases of clear-fluid meningitis were found among HIV-infected patients, representing 51.7% of cerebro-meningeal diseases and 92% of meningitis encountered in those patients. Sex ratio MIF was 1.5 and the mean age of patients was 40.7 years [range 23-61 years]. Clinical presentations comprised headache (80%), fever (67%), meningeal syndrome (74%), coma (28%), convulsions (9%), focal neurological deficits (11%), cranial nerves dysfunction (9%). Aetiologies were represented by neuromeningeal cryptococcosis (29 cases) and tuberculous meningitis (5 cases). In 26% of cases no aetiology was found. The case fatality rate was 63% overall (29 deaths) and 83.3% among cases with unknown aetiology. It did not vary significantly according to epidemiological and clinical variables studied. Neurological sequelae were found in 4 patients who recovered. A better management of clear-fluid meningitis among HIV-positive patients should benefit from the reinforcement of our diagnostic capacities, the availability of effective systemic antifungal drugs and the prevention of opportunistic infections in the course of HIV/AIDS infection.

The authors report the results of a survey on the efficacy against mosquito bites of a repellent, Mousticologne Spécial Zones Infestées (DEET 20%, EHD 15%). Two forms of the product, spray and gel, were tested in Senegal. Repellent efficacy was evaluated by exposing volunteers, both repellent-treated and untreated, to mosquito bites. The number of mosquito bites per person and per night was 0.63 in the spray treated group (group 1), 6.03 in the gel treated group (group 2) and 94.17 in the untreated group (group 3). The analysis of these results showed a significant difference between treated and untreated persons. Untreated persons were not protected against mosquito bites, persons treated with the spray were protected for 12 hours and those treated with the gel had over 8 hours' protection. We concluded that a single application of the repellent Mousticologne in the field is capable of ensuring all-night protection against mosquito bites.

In order to evaluate the in vivo efficacy of chloroquine in the treatment of P. falciparum malaria, studies have been carried out in Richard-Toll, Fatick and Tambacounda, 3 areas where dynamics of transmission, population movements, as well as prophylactic and curative practises are different. Failure rates in treatment were 13% in site 1 (Richard-Toll) where medical pressure and population movements are high. In sites 2 and 3 (Fatick and Tambacounda), the failure rate was 3%. Even if medical pressure is lower in the latter site (Tambacounda), the higher transmission could be a factor in the spreading of resistance. A surveillance system and better use of chloroquine must be undertaken.

Thanks to a serological survey carried out in Dakar from January to November 1993 among 353 procreative women, immune cover regarding toxoplasmosis was assessed using ELISA methodology: 40.2% of the surveyed population had antibodies of toxoplasmosis. No evidence of age, pregnancy, number of previous pregnancies was noted in antitoxoplasmosis antibodies prevalence. The seroconversion risk seems to be low even when it has existed during pregnancy. Contamination occurred during childhood. Some sanitary education should be provided to the procreative population in order to achieve a better compliance with basic hygiene regulations during pregnancy.

A survey of endemic malaria in Dakar was carried out in the southern sanitary district covering the city centre and neighbouring areas. The survey was scheduled from June 1994 to May 1995 in 12 sites distant from each other by 1000 to 1500 meters. Clinical and parasitological data were collected during weekly medical follow-ups at the patients' home with the systematic research of Plasmodium once a month. The study included 2,337 persons aged between 1 month and 88 years and belonging to 284 volunteer resident families. Through monthly parasitological examinations, a parasite rate (P.R.) of 0.3% and a gametocyte rate (G.R.) of 0.005% were recorded. Only Plasmodium falciparum was observed. The P.R. varied according to age: from 0.1% in the children under 2 years to 0.7% in the young adults (15-20 years) who appeared significantly more affected than the other age groups, including that of children from 2 to 9 years, of whom only 0.3% were infected by the parasite. The P.R. varied also according to the site surveyed: from 0% in the city centre to 1.3% at the periphery of the sanitary district and according to the time of year, reaching its height of 0.8%, between October and December, that is just after the rainy season. At the end of the year of survey, 929 among those surveyed were considered to have been satisfactorily followed. Their annual incidence rate was 2.4% for the parasitemia and of 1.5% for the malaria attacks. None of the participants aged under 2 years had the parasite. Among the others, the annual incidence rate varied according to the age--although not significantly--passing from 1.1% to 5.3% for parasitemia and from 0.4% to 3.0% for malaria attacks. Theses rates did not differ significantly according to site; the cases registered varied between 1% and 8% for parasitemia and 1% and 5.8% for malaria attacks. Only 10.6% of febrile subjects suffered from malaria attacks, but this rate seemed to go up between October to December, rising to 26.6% which corresponds to 1 case of malaria attacks for 4 cases of hyperthermia in that period. Weak density of Anopheline population and satisfactory medical surveillance explain the recorded results.

In order to assess the parasitic risk for street-food consumers, the authors conducted two studies from September to August 1996, one on street-food sellers (305) and the other on consumers (235). Among the consumers, 127 were considered as not exposed to risk, since they did not frequent the sector being surveyed, and 108 were exposed because they consumed at least one meal per day cooked by the sellers of this area. Both groups filled out a questionnaire and had their stools analysed according to the RITCHIE method. The infection rate was 60% among sellers and 45.5% among consumers. Protozoans were predominant in both groups. Among the consumers, those exposed were significantly more infected. Even though the sellers represent a parasitic risk due to their level of infection and the typology of parasites they shelter, one cannot assume that consumers are contaminated only by the sellers of street food. However, appropriate measures must be implemented in order to minimize risks for street-food consumers.

In Touba, more important accessibility to antimalarial drugs and their uncontrolled use let to assure that the rate of malarial morbidity would be lower there than in other place in Senegal whereas the rate of chloroquine resistance would be higher. A checking survey of these assumptions has been carried out from october 15 to november 10, 1995 in Touba's health center. Among 227 feverish subjects investigated, 111 were Plasmodium falciparum carriers. Malarial bouts accounted for 48.9% of the feverish fits observed and for the major cause of consultation during the rainy season. These figures are higher than those usually observed in urban environment. Conversely, the rate of chloroquine resistance is lower than those observed in urban zones, since the therapeutic efficacy of chloroquine on Plasmodium falciparum was 100% in that survey.