BackgroundInfectious diseases caused by multiresistant microbial strains are on the increase. Fighting these diseases with natural products may be more efficacious. The aim of this study was to investigate the in vitro antimicrobial activity of methanolic, ethylacetate (EtOAc) and hexanic fractions of five Cameroonian medicinal plants (Piptadeniastum africana, Cissus aralioides, Hileria latifolia, Phyllanthus muellerianus and Gladiolus gregasius) against 10 pathogenic microorganisms of the urogenital and gastrointestinal tracts.MethodsThe fractions were screened for their chemical composition and in vivo acute toxicity was carried out on the most active extracts in order to assess their inhibitory selectivity.The agar well-diffusion and the micro dilution methods were used for the determination of the inhibition diameters (ID) and Minimum inhibitory concentrations (MIC) respectively on 8 bacterial species including two Gram positive species (Staphylococcus aureus, Enterococcus faecalis), and six Gram negative (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Shigella flexneri, Salmonella typhi) and two fungal isolates (Candida albicans, Candida krusei). The chemical composition was done according to Harbone (1976), the acute toxicity evaluation according to WHO protocol and the hepatic as well as serum parameters measured to assess liver and kidney functions.ResultsThe chemical components of each plant's extract varied according to the solvent used, and they were found to contain alkaloids, flavonoids, polyphenols, triterpens, sterols, tannins, coumarins, glycosides, cardiac glycosides and reducing sugars. The methanolic and ethylacetate extracts of Phyllanthus muellerianus and Piptadeniastum africana presented the highest antimicrobial activities against all tested microorganisms with ID varying from 8 to 26 mm and MIC from 2.5 to 0.31 mg/ml. The in vivo acute toxicity study carried out on the methanolic extracts of Phyllanthus muellerianus and Piptadeniastrum africana indicated that these two plants were not toxic. At the dose of 4 g/kg body weight, kidney and liver function tests indicated that these two medicinal plants induced no adverse effect on these organs.ConclusionThese results showed that, all these plant's extracts can be used as antimicrobial phytomedicines which can be therapeutically used against infections caused by multiresistant agents.Phyllanthus muellerianus, Piptadeniastum africana, antimicrobial, acute toxicity, kidney and liver function tests, Cameroon Traditional Medicine

Lower respiratory tract infections (LRTIs) remain a challenge in African healthcare settings and only few data are available on their aetiology in Cameroon. The purpose of this study was to access the bacterial cause of LRTIs in patients in Cameroon by two methods. Methods. Participants with LRTIs were enrolled in the referral centre for respiratory diseases in Yaoundé city and its surroundings. To detect bacteria, specimens were tested by conventional bacterial culture and a commercial reverse-transcriptase real-time polymerase chain reaction (RT-PCR) assay. One hundred forty-one adult patients with LRTIs were enrolled in the study. Among the participants, 46.8% were positive for at least one bacterium. Streptococcus pneumoniae and Haemophilus influenzae were the most detected bacteria with 14.2% (20/141) followed by Klebsiella pneumoniae, 9.2% (13/141), Staphylococcus aureus, 7.1% (10/141), and Moraxella catarrhalis, 4.3% (6/141). Bacterial coinfection accounted for 23% (14/61) with Haemophilus influenzae being implicated in 19.7% (12/61). The diagnostic performance of RT-PCR for bacteria detection (43.3%) was significantly different from that of culture (17.7%) (p< 0.001). Only Streptococcus pneumoniae detection was associated with empyema by RT-PCR (p<0.001). These findings enhance understanding of bacterial aetiologies in order to improve respiratory infection management and treatment. It also highlights the need to implement molecular tools as part of the diagnosis of LRTIs.

AimThe epidemiology of human respiratory syncytial virus (HRSV) infection has not yet been systematically investigated in Africa. This systematic review and meta‐analysis are to estimate the prevalence of HRSV infections in people with acute respiratory tract infections (ARTI) in Africa.MethodWe searched PubMed, EMBASE, Africa Journal Online, and Global Index Medicus to identify observational studies published from January 1, 2000, to August 1, 2017. We used a random‐effects model to estimate the prevalence across studies. Heterogeneity (I 2) was assessed via the chi‐square test on Cochran's Q statistic. Review registration: PROSPERO CRD42017076352.ResultsA total of 67 studies (154 000 participants) were included. Sixty (90%), seven (10%), and no studies had low, moderate, and high risk of bias, respectively. The prevalence of HRSV infection varied widely (range 0.4%‐60.4%). The pooled prevalence was 14.6% (95% CI 13.0‐16.4, I 2 = 98.8%). The prevalence was higher in children (18.5%; 95% CI 15.8‐21.5) compared to adults (4.0%; 95% CI 2.2‐6.1) and in people with severe respiratory tract infections (17.9%; 95% CI 15.8‐20.1) compared to those with benign forms (9.4%; 95% CI 7.4‐11.5); P‐values <0.0001. The HRSV prevalence was not associated with sex, subregion in Africa, setting, altitude, latitude, longitude, and seasonality.ConclusionThis study suggests a high prevalence of HRSV in people with ARTI in Africa, particularly among children and people with severe clinical form. All innovative strategies to curb the burden should first focus on children which present the highest HRSV‐related burden.

BackgroundHuman adenoviruses (HAdVs) cause a wide range of diseases worldwide, including respiratory infections. Studies on HAdV molecular epidemiology are limited in Cameroon. The purpose of this study is to document the different types HAdV circulating in Cameroon in children with acute respiratory infections.MethodsNasopharyngeal swabs were collected from 811 children under 15 years from 2011 to 2014. The HAdV detection was assessed by semi-quantitative generic PCR r-gene®. The HAdV-positive samples were typed by amplification and sequencing of partial hexon gene and a real-time PCR. Demographic data were collected and analyzed. The infection and hospitalization risk factors were assessed thought the Chi-square test.ResultsA total of 137/220 HAdV-positive samples were amplified successfully. Six species of HAdV (Mastadenovirus A to F) were detected with B (108/220) and C (47/220) being the predominant strains. Hospitalization and age were significantly associated to HAdV-B and HAdV-C respectively. Phylogenetic analysis of HAdV-B3 virus (18) and B7 (5) shows a conserved and a significant temporal stability in relation to the reference sequence (99.1 to 100% of similarity).ConclusionThis study reported HAdV species and types detected in children with acute respiratory infections in Cameroon between September 2011 and July 2014. These results support further evaluation of the spatio-temporal circulation pattern of HAdV species and types in Cameroon.

BackgroundDrug-resistant tuberculosis, especially multidrug-resistant tuberculosis (MDR-TB), is a major public health problem. Effective management of MDR-TB relies on accurate and rapid diagnosis. In this study, we assessed the diagnostic accuracy of the Genotype MTBDRplus assay in diagnosing MDR-TB in Cameroon, and then discuss on its utility within the diagnostic algorithm for MDR-TB.MethodsIn this cross-sectional study, 225 isolates of Mycobacterium tuberculosis cultured from sputum samples collected from new and previously treated pulmonary tuberculosis patients in Cameroon were used to determine the accuracy of the Genotype MTBDRplus assay. We compared the results of the Genotype MTBDRplus assay with those from the automated liquid culture BACTEC MGIT 960 SIRE system for sensitivity, specificity, and degree of agreement. The pattern of mutations associated with resistance to RIF and INH were also analyzed.ResultsThe Genotype MTBDRplus assay correctly identified Rifampicin (RIF) resistance in 48/49 isolates (sensitivity, 98% [CI, 89%–100%]), Isoniazid (INH) resistance in 55/60 isolates (sensitivity 92% [CI, 82%–96%]), and MDR-TB in 46/49 (sensitivity, 94% [CI, 83%–98%]). The specificity for the detection of RIF-resistant and MDR-TB cases was 100% (CI, 98%–100%), while that of INH resistance was 99% (CI, 97%–100%). The agreement between the two tests for the detection of MDR-TB was very good (Kappa = 0.96 [CI, 0.92–1.00]). Among the 3 missed MDR-TB cases, the Genotype MTBDRplus assay classified two samples as RIF-monoresistant and one as INH monoresistant.The most frequent mutations detected by the Genotype MTBDRplus assay was the rpoB S531 L MUT3 41/49 (84%) in RIF-resistant isolates, and the KatG S315 T1 (MUT1) 35/55 (64%) and inhA C15T (MUT1) 20/55 (36%) mutations in INH-resistant isolates.ConclusionThe Genotype MTBDRplus assay had good accuracy and could be used for the diagnosis of MDR-TB in Cameroon. For routine MDR-TB diagnosis, this assay could be used for Mycobacterium tuberculosis cultures containing contaminants, to complement culture-based drug susceptibility testing or to determine drug resistant mutations.