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Insects entertain intricate and mutualistic relationship with an array of microorganisms, which significantly influence their fitness, ecology and evolution. In recent decades, there has been increasing interest toward studying the effects of microbiome on many host insects (Dipterans, Lepidopterans, and Coleopterans). Studies so far realized indicate that gut microbiome contribute to host nutritional ecology, defense, immunity and lifespan. Bactrocera dorsalis (Tephritidae: Diptera) is a polyphagous fruit fly which attacks a huge variety of fruits and vegetables worldwide and has been placed as a quarantine species by many countries. To investigate the specific functions of the gut endosymbionts, it is a prerequisite to know the composition of gut bacterial communities whose manipulation will help to decipher their ecological relevance. Here, we used the culture-dependent technique to isolate and identify gut bacteria from B. dorsalis at different developmental stages. The results revealed 11 bacterial species from the third instar larvae, 18 and 12 from female and male populations, respectively. These bacteria were assigned to six families, namely, Enterobacteriaceae, Enterococcaceae, Staphylococcaceae, Streptococcaceae, Micrococcaceae and Bacillaceae. Bacterial species from these families were differentially represented in various samples, except Klebsiella oxytoca , Enterobacter cloacae, Pantoea dispers and Enterococcus faecalis that were detected at all developmental stages. Overall, Enterobacteriaceae was the most dominant family in females and third instar larvae accounting for 57.89% and 26.32%, respectively, while Enterococcaceae was dominant in males with 75% of the total bacterial taxa. These results suggest that B. dorsalis possesses a huge variety of cultivable bacteria that could be used to explore their specific functions on host physiology and fitness.

In order to understand the role of symbionts for their insect hosts, it is customary to treat them with antibiotics or to sterilize eggs (treatments), resulting in aposymbiotic and axenic insects, respectively. Such axenic insects can then be compared with untreated controls. Fruit flies often bear complex communities which are greatly reduced by such treatments. However, the bacterial community is not completely eliminated. Here, we examine the effect of these procedures on the structure of the remaining bacterial communities in Bactrocera dorsalis (Diptera: Tephritidae) and on the insect longevity. The antibiotics (Norfloxacin and Ceftazedime) were administered to 1-day-old adult flies through sugar meal for 7 days, and eggs were surface sterilized and dechorionated to produce axenic lines. The flies were starved of protein before they were offered full diets or diets containing non-essential amino acids only. Antibiotic and egg disinfection treatments resulted in a significant reduction of the vast majority of gut bacterial populations, especially Proteobacteria, Firmicutes and Bacteroidetes. On the other hand, antibiotic allowed the persistence of Actinobacteria, Cyanobacteria and Acidobacteria populations. In untreated control flies, longevity was extended irrespective of diet quality in comparison to treated flies. Conversely, when gut bacteria were largely reduced (aposymbiotic and axenic flies), longevity was reduced in the non-essential amino acids diet treatment versus slightly improved in the presence of a protein diet. We discuss these results in an ecological–life-history perspective.

In the resource-limited countries, CD4 count and viral load (VL) determination are not always systematic, due to the low follow-up coverage and/or limited access to optimal hospital facilities. The present study aimed at evaluating the clinical role of Serum Protein Electrophoresis (SPE) in HIV health care and disease control. An analytic study was conducted in a Cameroon reference’s hospital, in HIV patients on antiretroviral treatment. Blood sample was collected to perform CD4 count, viral load, total proteins, and SPE through clinical capillary electrophoresis. SPE data were correlated to other results. ANOVA, Mann-Whitney test and Pearson’s correlation were performed, at the threshold P

In this cross-sectional study, we investigated host genetic factors and ethnic variation in circulating Plasmodium falciparum merozoite surface protein 2 (msp-2) clones among children with asymptomatic malaria. Isolates from seventy two asymptomatic malaria children were used for genotyping block 3 of msp-2 gene by nested polymerase chain reaction (PCR). Sickle cell trait and glucose-6-phosphate dehydrogenase (G6PD) deficiency were analysed by restriction fragment length polymorphism of DNA products from PCR targeting codons 6 and 68 of the beta-globin (HBB) and G6PD genes respectively. ABO blood group was typed by agglutination method. A total of forty two msp-2 genotypes (20 for 3D7 and 22 for FC27) were detected for an average (standard error of mean) multiplicity of infection (MOI) of 2.45 (0.16). The MOI was statistically the same among the five identified ethnic groups (P = 0.83). The overall prevalence of sickle cell trait and G6PD deficiency were 12.50 % and 22.22 % respectively. MOI was similar between children with Hb AA and Hb AS genotypes (P = 0.42). MOI was significantly high among children with a mutant G6PD genotype (P = 0.017). MOI was significantly higher in blood group O than group A (P = 0.03). Our findings show that although ethnicity and sickle cell trait have no association with MOI, the association was observed with G6PD genotype and ABO group. The results suggest the need for extension and expansion of the current study in order to investigate the mechanisms involved.

Background: Infections with Herpes Simplex Virus Type-2 (HSV-2) and Chlamydia trachomatis is the most common cause of genital ulcer disease and cervicitis worldwide. There is little information on the prevalence of these sexually transmitted infections (STIs) in Cameroon. The aim of this Original Research Article Luther et al.; BJMMR, 7(3): 224-230, 2015; Article no. BJMMR.2015.327 225 study was to evaluate the seroprevalence and behavior factors associated with Chlamydia trachomatis and HSV-2 seropositvity among women attending AIDS care unit in the district hospital in Douala. Methodology: One hundred and fifty seven consenting women (80 HIV-1 positive and 77 HIV-1 negative) were invited to participate in this study. A structured questionnaire was used for each woman to obtain informations about socio-demographic characteristics and sexual risk behavior. Peripheral venous blood sample were collected, labeled and sent to the laboratory, where the presence of IgG antibody against HSV-2 and Chlamydia trachomatis was detected, using ELISA test. Data management was carried out using the SPSS 16.0 statistical software. Results: The mean age of women was 37.22±9.13 years (range, 20 to 74 years). Of the 157 women tested, 122 (77.7%) were HSV-2 positive and 60 (38.2%) were positive for chlamydial infection. The prevalence of HSV-2 and chlamydial infections in HIV positive patients were 73.7% and 43.7% respectively versus 81.8% and 32.5% in HIV negative individuals. Women with multiple infections were those belonging to the group aged 30-39 years old, single and having had more than three sexual partners during the six months preceding the study. Conclusion: HIV status appears tobe a factor in the acquisition of chlamydial infection in our population. These results suggest the need for extension and expansion of the current study in Cameroon.

The gold standard for malaria diagnosis is the microscopic examination of Giemsa stained thick blood smears though microscopy mostly may not detect the presence of Plasmodium species infections in asymptomatic samples. In the reported study, we used two diagnostic methods viz. the conventional microscopic examination and polymerase chain reaction (PCR) assay to analyse the asymptomatic malaria samples. PCR assay amplifying 18S small-subunit ribosomal RNA (SSU rRNA) gene of Plasmodium in 122 samples confirmed 68% of isolates as asymptomatic P. falciparum infections; with 87.9% mono-infections. We observed that the P. malariae positive samples were not diagnosed in microscopic examination of the blood smears but the PCR based diagnostic method revealed the presence of 12% P. malariae infections in asymptomatic samples from Yaounde region of Cameroon where no official cases of P. malariae have been reported for over a decade. The sequence analysis further confirmed the presence of 12% P. malariae in malaria positive samples with three base pair deletions and five substitutions in the SSU rRNA gene.