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M Cot

Publications and source records attributed to M Cot.

At least 55 records · Page 3Linked to original sources
PubMed1993

Experimental infections of Anopheles gambiae with Plasmodium falciparum of naturally infected gametocyte carriers in Cameroon: factors influencing the infectivity to mosquitoes.

Factors which could influence the success of experimental infections of Anopheles gambiae with Plasmodium falciparum were investigated in Cameroon. 139 experimental infections with different gametocyte carriers were performed. 86 (62%) gave rise to mosquito infection after dissection of at least 20 mosquitoes. Among succeeding infections, the mean percentage of infected mosquitoes was 18.6% and mean oocyst load per positive midgut was 2.56. Only gametocyte density was identified as a factor which determined the success and the level of mosquito infection. No significant influence was found for sex and age of the gametocyte carrier, body-temperature, presence of asexual erythrocyte stages, rhesus factor, blood group and use of antimalarial drugs (chloroquine and amodiaquine).

ABO Blood-Group System↗
PubMed1993

[Malaria in the village of Yaounde (Cameroon). 3. Parasitological study in 2 central districts].

A parasitological study of malaria was carried out in two central districts of Yaounde (Cameroon) for one year. The Essos district was built near marshy shallows. The Obili district was comparable to Essos but there were many poorly maintained fish breeding pounds. Surveys were carried out quarterly in each district with a sample of 22 and 16 families at Essos and Obili respectively. The whole members of the families were examined. The study showed that the plasmodic index cumulated for the two districts was 25.4 +/- 2.7% (n = 960). The gametocytic index was 1.7 +/- 0.8% and the parasitic density was 310 parasites/microliters of blood. A significative difference in the plasmodic index was observed between the two districts: 28.7 +/- 3.6% (n = 592) in Essos and 20.1 +/- 4.1% (n = 368) in Obili (p < 0.02). The plasmodic index was higher in the 6 to 15 age group (37.5%) but the higher parasitic density was observed in the 0 to 5 age group (1,100 parasites/microliters of blood). Seasonal variations were noticed with the higher indexes in small dry season and the lower indexes in the big dry season.

Adolescent↗
PubMed1992

Effect of chloroquine chemoprophylaxis during pregnancy on birth weight: results of a randomized trial.

To determine the effect of chloroquine chemoprophylaxis during pregnancy on birth weights, a randomized trial was carried out in 1987 and 1988 in Banfora, Burkina Faso (West Africa). Seven hundred forty-five randomly selected women treated with chloroquine sulfate were compared to with 719 controls who received no treatment. In spite of an unquestionable effect of chloroquine in preventing placental infection (4.1% infected placentas in the treated group versus 19.0% in the controls), the mean difference in birth weights between the two groups (6 g) was not significant. The difference in the proportion of low birth weight (LBW) newborn babies in two groups (16.3% versus 16.4%) was also not significant. However, there was a strong relationship between placental infection and birth weight (the mean birth weight difference between infected and uninfected placentas was 113 g, and the proportion of LBW babies was 26.0% in infected placentas versus 14.8% in uninfected placentas). The small difference in birth weights observed between the two groups may be due to the fact that the prevalence rate of placental infection is low and that prophylaxis is effective only on a portion of the subjects in the treated group. It may also indicate that malaria is only one of several risk factors responsible for LBW. The relatively small increase in birth weight, the expected poor acceptance of mass prophylaxis, and the spreading of chloroquine-resistant Plasmodium strains should be considered before extending malaria chemoprophylaxis to all pregnant women. It might be worth considering to limit prophylaxis to primigravidae.

Adult↗
PubMed1992

[Complement to the epidemiologic study of the focus of Schistosoma mansoni bilharziasis in Kara (northern Togo)].

The present study on the focus of schistosomiasis mansoni of Kara (Northern Togo) complements a report already published in the Bulletin de la Société de Pathologie Exotique in 1988 (9). The following results were obtained through different experiments carried out with snails collected in Kara. According to the season, 3 to 15% of the Biomphalaria pfeifferi studied, were infected. The maximal release of cercariae was observed between 11 am and 1 pm. The survival of cercariae and their ability to infect mice were not superior to 16 hours. Data obtained with the chaetotaxy of miracidia of the Kara strain were compatible with those obtained with african strains by other authors. Moreover, B. pfeifferi from Kara was more susceptible to the Kara strain of Schistosoma mansoni than B. pfeifferi collected in the south of Togo or than B. glabrata from the new world. On the contrary, B. pfeifferi from Kara was susceptible to a strain of S. mansoni from Brazil and was able to produce infectious cercariae. In addition, the search for an animal reservoir was carried out; 3 of the 112 (2.7%) wild rodents captured around the river Kara, were infected. This relatively low number of infected rodents was compatible with the usual findings in Africa where the animal reservoir is considered from human origin and has no importance in the transmission of S. mansoni as it could have in South America and West Indies.

Animals↗
PubMed1992

Segregation analysis detects a major gene controlling blood infection levels in human malaria.

The profound influence that the genetic makeup of the host has on resistance to malaria infection has been established in numerous animal studies. This genetic heterogeneity is one of the main causes of the difficulties in developing an effective malaria vaccine. Segregation analysis is the first step in identifying the nature of genetic factors involved in the expression of human complex diseases, as infectious diseases. To assess the role of host genes in human malaria, we performed segregation analysis of blood parasite densities in 42 Cameroonian families by using both the unified mixed model and the class D regressive model of analysis. The results provide clear evidence for the presence of a recessive major gene controlling the degree of infection in human malaria. Parameter estimates show a frequency of .44-.48 for the deleterious allele, indicating that about 21% of the population is predisposed to high levels of infection.

Adolescent↗
PubMed1991

[Comparison of 2 field methods for urinary assay of chloroquine].

Two methods of urinary chloroquine assay were tested in pregnant women in the town of Banfora (Burkina Faso): the method with bromothymol blue (Bergqvist) and the method with methyl-orange (Haskins and Mount or HMM II). Urinary assay of chloroquine was performed with both methods in 45 women chosen at random whether or not under chemoprophylactic treatment (21 taking a weekly prophylaxis of 300 mg of chloroquine, and 24 controls). The HMM II method proved to be more sensitive (100%) and more specific (91.7%) than the Bergqvist method (80.9% and 83.3% respectively); it was also more reliable with regard to positive (91.3% versus 80.9%) and negative (100% versus 91.3%) predictive values. Moreover, the quantitative appreciation of the levels of chloroquine excretion proved to be superior with the HMM II method. Finally, this method is faster to perform, easier to use and cheaper, making it the method of choice for field assay of chloroquine in urine.

Azo Compounds↗
PubMed1983

[Mass treatment of Schistomsoma haematobium bilharziasis in the member states of the Organization for Coordination of the Campaign against Endemic Diseases in Central Africa].

The authors analysed the results of the control of Schistosoma haematobium bilharziasis in two central African countries, the Congo and the Cameroun . These results demonstrated: --The feasibility of mass screening by filtering urine; --The acceptability and efficacy of new antibilharzian drugs, praziquantel and oltipraz . With the aim of improving the cost/effectiveness ratio of these campagnes and taking into account the health requirements which exist and/or are desired by the population, the authors propose four modifications of the strategy of mass control: --The integration of Schistosoma haematobium bilharziasis control with the other regional health priorities; --Screening target groups;

Adolescent↗
PubMedDate not supplied

Antibodies to the ring-infected erythrocyte surface antigen and the circumsporozoite protein of Plasmodium falciparum in a rural community from Burkina Faso.

A population-based study in Burkina Faso was conducted to determine, under conditions of natural exposure to malaria parasites, the prevalence rate and seasonal variation of antibodies to the repeated amino acid sequences of the Plasmodium falciparum ring-infected erythrocyte antigen (RESA) and the circumsporozoite (CS) protein, and the relationship of the presence of malaria parasites in the blood with the level of these antibodies. A random sample of households was selected and visited twice during 1988, in April just before the rainy season and in September at the end of the rainy season. Serological testing included an immunofluorescent assay for total anti-blood stage antibodies; a modified immunofluorescent assay on glutaraldehyde-fixed parasitized erythrocytes to detect antibodies to RESA; and an enzyme-linked immunosorbent assay (ELISA) using synthetic peptides representing repeat amino acid sequences of RESA [(EENV)5, (EENVEHDA)4, and (DDEHVEEPTVA)2] and CS protein [(PNAN5)]. In April, at the end of the dry season, 98% of the individuals had total P. falciparum antibodies, and 39% had anti-RESA antibodies. 32%, 82%, 80%, and 41% of the individuals had antibodies to the respective peptides. All prevalence rates increased with age. After the rains, in September, prevalence rates and levels of reactivity increased in each serological assay, except in the ELISA with (DDEHVEEPTVA)2. Presence of P. falciparum parasitaemia was inversely related to antibody response to the CS protein (PNAN)5 peptide but not to any other assay.

Adolescent↗