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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.

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.

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.

The study of malarial seroprevalence in Dakar has interested 598 women among whom 377 pregnant and 221 non pregnant, between 15 to 45 years old and happens during the dry season, period of which malaria transmission is practically stopped in the locality. Among the tested serums by indirect immunofluorescence with Plasmodium falciparum asexual blood forms as antigen, 24.4% contained antimalarial antibodies. The serological index does'nt vary significantly according to the months during the dry season, the women age and their previous pregnancy number. On the contrary, the women who live in Dakar since less than 2 years, have e higher seropositivity rate of 33.7% than those who are there since more than 2 years, 20.0%. It is likewise for the women practicing chemoprophylaxy with chloroquine of whom 16.5% have antibodies against 26.0% among those who don't practice it. The seropositivity rate doesn't vary significantly according as the women are pregnant (24.7% of positive) or not pregnant (24.0% of positive). The weakness of the serological rate in the examined women, can be explained by the situation of Dakar in a weak malarial hypoendemic area. II shows that the major examined subjects have lost or have never had contact with Plasmodium what predispose them to make severe and complicated malarial attacks.

The authors carried out an epidemiological survey from october 12 to december 4, 1995, at Medina's mother and Child care centre (MCC) in Dakar in order to assess chemoprophylaxis among pregnant women in Dakar. The midwife/pregnant women ratio is 0.08 The mentioned diagnosis criteria were relevant regards to the references established for most of the answers because since the latter base malaria diagnosis on the following signs: fever, chills, headaches and vomiting. 64.6% of them assume compliance to antimalarial chemoporphylaxis. Education level seems to be the main determining factor in this trend. Although chloroquine is the most widely used drug, nevertheless 11.9% of pregnant women assuming compliance use it at inappropriate posology. Besides, pyrimethamine is used by 12.3% of them. 34% of pregnant women do show chloroquine in urine. The plasmodial index is 1.4%. Only 8.1% of these women are supplied by health centres where shortages are noted.

To establish the seroprevalence of toxoplasmosis in women during their reproductive years, we examined 720 women, of whom 404 were pregnant and 306 were not, all residing in and around Dakar. Of the serum tested by indirect immunofluorescence, 40.3% contained antibodies recognizing toxoplasmosis. The seroprevalence did not vary significantly with the age of the women, the number of previous pregnancies, the place of residence or the length of residence in Dakar. It was higher in the pregnant women (44.4%) than in the nonpregnant women (37.2%), but this difference is not statistically different. The titers of antibodies were generally weak, varying between 10 and 320 IU/ml of serum. Also, IgM specific antibodies were absent. These results indicate that the seroconversion had occurred previously, probably at a young age. We observed seroprevalences higher than those obtained by authors using comparable techniques twenty years ago. This indicates an increase of the transmission of toxoplasmosis in the population. Few women during their reproductive years had antibodies against toxoplasmosis. Thus, they are at risk of developing a primary infection during a pregnancy. This undergoes the necessity of promoting measures to prevent toxoplasmosis infection in pregnant women.

The comparison of the prevalence of malaria in pregnant and non pregnant women living in Dakar has interested 1819 women among whom 950 pregnant and 869 non pregnant. For all the examined women, the global plasmoidic index was 2.6% and the gametocytic index 0.1%. Plasmodium falciparum was the only observed species. According to the obtained results, pregnant women, with a plasmoidic index of 4.5% are more often parasited than the non pregnant women, only affected in a proportion of 0.5% Whatever the age, the number of previous pregnancy, the place of residence, the duration of the stay in Dakar may be, the pregnant women are always more often parasited than the non pregnant women and the registered differences are statistically significant. That situation could come from a greater receptivity of the pregnant women what is admitted by some authors. But a more important proportion of natives from rural area was observed among the pregnant women, from where a difference in the exposure to the risk of impaludation between the two groups that could explain the registered results. The global plasmoidic index of 2.6% obtained in the examined women, reflects well the present situation of the malaria endemy in Dakar, a weak hypo-endemic area.