Potential Risk of Transmission of Escherichia coli and Salmonella spp. Infections by the Musca domestica Fly and the Periplaneta americana Cockroach in the City of Cotonou (South Benin)

Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species of flies and cockroaches that cohabit with humans in the city of Cotonou and determine the contribution of Musca domestica and Periplaneta americana in the transmission of bacteria responsible for infections in humans. Methods: Capture sessions during the day for flies and at night for cockroaches were carried out in 4 arrondissements of the city of Cotonou. The insects collected were transported to the Center of Research Entomological of Cotonou for identification, then sent to the Section Hygiene of Water and Food for microbiological analysis, enumeration and testing for human pathogenic bacteria. Results: A total of 351 flies and 26 cockroaches were collected at the sites, including two synanthropic species belonging to two families each. Musca domestica and Periplaneta americana were the most abundant species found after identification in the city of Cotonou. Thermo-tolerant coliforms and Escherichia coli were found on all specimens at varying concentrations. Salmonella spp. bacteria were identified in the fly population from the Dantokpa dump. Conclusion: Flies and cockroaches can transmit microorganisms to humans. The presence of Salmonella spp. among the specimens revealed that infections frequently caused by contaminated food or water are also transmitted to humans by flies. The presence of these germs on flies and cockroaches represents a potential risk of mechanical transmission to humans. It is, therefore, essential to continue investigations in order to assess the species of bacteria propagated, improve control strategies against these troublesome insects and adopt better hygiene conditions for better living.

Comparative Study of the Widal Test against Stool Culture in the Diagnosis of Suspected Cases of Typhoid Fever in Some Low Income Communities in the Adamawa Region of Cameroon

Introduction: Infectious diseases constitute a major concern of public health in developing countries. Facilities and well trained staff have been shown to be one of the major obstacles in the rapid and quality diagnosis of these diseases. As such, we carried out an analysis to compare the Widal test and stool culture to identify febrile patients with Salmonella infection. Method: A cross sectional study was conducted to diagnose salmonella infection with out-patients who demonstrated signs of salmonella infection. Serum was harvested from blood collected from 368 (Vina = 234, Mayo Banyo 65, and Djerem = 69) patients accompanied by stool, Widal test was conducted on the spot and stool was taken to a reference laboratory for culture using standard microbiological methods, sociological set up was calculated in percentages, prevalence was calculated using excel while statistical difference was calculated using SPSS. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to compare the Widal test against stool culture. Results: A total of 368 (50.8% females and 49.2% males) participants took part in the survey. Salmonella prevalence (66.24%) in stool culture in the Vina division was significantly different (p 0.05). The sensitivity,specificity, PPV, and NPV of slide agglutination test against stool culture varied from different areas (Vina: 51.6%, 73.62%, 79.21% and 43.61%;Mayo Banyo: 60.53%, 77.78%, 79.31% and 58.33%;Djerem: 53.18%, 83.73% 73.91% and 67.39%) respectively. Slide agglutination test has a fair agreement with the stool culture (kappa, Vina = 0.202;Mayo Banyo = 0.37 and Djerem = 0.38). Conclusion: Generally, in the three areas of study, the Widal test had a fair correlation with the stool culture;This means the Widal test should not be used alone but in combination with stool culture in the detection of salmonella infections.

Understanding the effects of intramuscular injection and feed withdrawal on Salmonella Typhimurium shedding and gut microbiota in pullets

Background:Gut microbiota plays a key role in health,immunity,digestion,and production in layers.Factors such as environment,diet,diseases,stress,and flock management significantly affect gut microbiota;however,it is not known how potential stressors such as intramuscular injections or feed withdrawal alter the composition of gut microbiota that result in increased the shedding level of foodborne pathogens.In the current study,the effects of intramuscular corticosterone injection and feed withdrawal were evaluated to understand their role in Salmonella Typhimurium shedding and changes in the composition of gut microbiota in layers.Results:Salmonella shedding was observed for 8 weeks post-infection.There was a significant increase in Salmonella Typhimurium count after intramuscular injection and feed withdrawal.The Salmonella infected and the negative control groups showed significant differences in the abundance of different genera in gut microbiota at week 1 and up to week 7 post infection.The infected group showed a significant reduction in alpha diversity of gut microbiota.Firmicutes reduced significantly(P<0.05)after intramuscular injection,while the feed withdrawal groups did not cause any significant changes in Proteobacteria-Firmicutes ratio.Furthermore,intramuscular injection resulted in a significant change in alpha diversity of gut microbiota.Conclusions:Exposure of chicks to relatively low dose of Salmonella Typhimurium can lead to persistent shedding in pullets.The Salmonella Typhimurium infection disrupted the gut microbiota composition immediately after infection.The potential stress of intramuscular injection and feed withdrawal significantly increased the Salmonella Typhimurium count in faeces.The intramuscular injection also resulted in a significant alteration of the Proteobacteria-Firmicutes ratio,which could increase the risk of dysbiosis.

Association of Phenotypic and Genotypic Fluoroquinolone Susceptibility among Non-Typhoidal Salmonella Isolates from Jeddah, KSA

Non-typhoid Salmonella (NTS) infects 250 to 3200 per 100,000 individuals from all over the world. NTS infection is relatively high in Jeddah (ranges between 44-132/100,000 population) as compared to other cities of Saudi Arabia. NTS isolates have also shown increasing resistance to conventional antibiotics. Therefore, fluoroquinolone (FQ) is considered drug of choice for the treatment of invasive NTS infections. A rapid detection of FQ resistance may greatly assist in appropriate therapy and containment of resistant NTS strains. Thus, molecular detection of mutations in FQ resistance genes (gyrA and parC) may play a promising role. Since limited data were available about FQ resistance among NTS isolates, therefore, this study primarily explored the occurrence of phenotypic and genotypic FQ resistance among NTS isolates from Jeddah, Saudi Arabia. Study also explored any correlation between phenotypic and genotypic FQ resistance. Fifty NTS isolates were collected from a public sector hospital of Jeddah from January to December, 2014. FQ susceptibility was determined for 48 NTS isolates using Kirby-bauer disk diffusion method and results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) methodology. Genotypic resistance to FQ was determined by exploring mutations in gyrA and parC genes using PCR- based gene-sequencing method. Results were statistically analyzed using Social Package of Statistical Science (SPSS) version 22. Phenotypic antibiogram revealed that 38% (18/48) NTS isolates were FQ resistant, that 23% (11/48) were intermediately susceptible and that 39% (19/48) were susceptible. Genotypic resistance revealed mutations in only four codons of gyrA and parC genes among 39% (7/18) of FQ resistant isolates. 43% (3/7) of FQ resistant isolates showed mutations at two codons 83 (S83F, S83Y) and 87, (D87G, D87Y, D87W) of gyrA gene. Two resistant isolates showed triple mutations i.e. at codons 83 and 87 of gyrA and codon 80 (S80I and S80W) of parC gene, while one resistant isolate revealed mutation at codon 87 of gyrA and 57 (S57T) of parC gene. Moreover, 55% (6/11) intermediately susceptible isolates for FQ also revealed mutation at codon 83 of gyrA gene whereas;one intermediately susceptible isolate (1/6) also revealed additional mutation at codon 57 of parC gene. None of the FQ susceptible NTS isolates showed any mutations in gyrA or parC genes. Occurrence of mutations at only four codons in gyrA and parC genes among FQ resistant isolates may assist in development of rapid molecular method for FQ resistance detection. Presence of mutations among more than fifty percent of intermediately susceptible FQ isolates is alarming and may serve as a predictor for pre-resistant isolates for FQ. Moreover, absence of mutation in about sixty percent of phenotypically FQ resistant NTS isolates shows existence of an alternate resistance mechanism requiring further investigations.

Assessment of Clinical Presentation, Performance of Diagnostic Methods and Antibiotic Susceptibility Testing for Salmonella among Patients Attending Kangema Sub-County Hospital, Kenya

Background: Typhoid disease remains a major public health problem globally, especially in developing countries in sub-Saharan Africa. Symptoms associated with typhoid disease mimic those of other febrile illnesses and are thus difficult to make an accurate diagnosis. A confirmed diagnosis requires the determination or isolation of the bacteria in well-equipped laboratories. Developing countries are faced with a huge limitation of the laboratory infrastructure to diagnose typhoid disease, which would otherwise guide in treating, managing, controlling, and halting the spread of drug resistant mutants. Objective: This study, therefore, was aimed at determining the clinical presentation, performance of diagnostic tests and antibiotic susceptibility testing of Salmonella among adults attending Kangema Sub-County Hospital. Study Population: The study population was residents of Kangema Sub-County in Murang’a County, Kenya while the target population was adults. Methods: The study adopted a cross-sectional study design that employed a systematic random sampling procedure. The study took place between April and June 2021. The sample size was 97 respondents who all consented and were enrolled in the study. Interviewing the respondents was carried out by administering structured questionnaires to collect quantitative data. Stool samples were obtained and cultured in Cary Blair transport media and then cultured in appropriate media at the Murang’a County Referral Hospital Laboratory. A rapid Salmonella Antigen (SAT) test was also performed on all the stool samples. Data Analyses: Word Statistics and Data (STATA) v 13 was used for statistical analysis. Results: The prevalence of Typhoid Fever was at 6.2% (95% CI) which included S. Typhi (n = 1;16.7%) and S. Paratyphi B (n = 5;83.3%). No isolate showed resistance to Ciprofloxacin. The sensitivity of SAT is 100% and a specificity of 98.9% with a kappa statistic of almost perfect agreement (0.9641) with culture. Patients who had fever p = 0.001, abdominal distention p = 0.028, diarrhoea p = 0.038, loose or watery stool p = 0.021 and mild general condition p = 0.02 remained independently associated with Salmonella infection. Conclusion: Typhoid Fever being endemic, laboratory diagnosis was a key for confirmation after clinical diagnosis. SAT can accurately be used to detect the disease where culture is unavailable. However, antibiotic sensitivity tests were crucial when determining the drug of choice as Salmonella isolates were multi-drug resistant. Establishment of prescribing antimicrobial policies and guidelines can periodically monitor the antibiogram patterns.

Faecal microbiota transplantation in patients with Clostridium difficile and significant comorbidities as well as in patients with new indications:A case series

Fecal microbiota transplantation(FMT) is effective in recurrent Clostridium difficile infection(r CDI). Knowledge of the safety and efficacy of FMT treatment in immune deficient patients is scarce. FMT has been suggested as a potential method for an increasing number of new indications besides r CDI. Among our FMT-treated r CDI patients, we reviewed those with major comorbidities: two human immunodeficiency virus patients, six haemodialysis patients, two kidney transplant patients, two liver transplant patients and a patient with chronic lymphatic leukaemia. We also reviewed those treated with FMT for indications other than r CDI: Salmonella carriage(two patients), trimethylaminuria(two patients), small intestinal bacterial overgrowth(SIBO;one patient), and lymphocytic colitis(one patient), as well as a common variable immunodeficiency patient with chronic norovirus infection and ESBL-producing Escherichia coli(E. coli) carriage. Of the thirteen r CDI patients treated with FMT, eleven cleared the CDI. The observed adverse events were not directly attributable to FMT. Concerning the special indications, both Salmonellas and ESBL-producing E. coli were eradicated. One trimethylaminuria patient and one SIBO-patient reported a reduction of symptoms. Three patients did not experience a benefit from FMT: chronic norovirus, lymphocytic colitis and the other fish malodour syndrome. There were no reported side effects in this group. FMT appeared to be safe and effective for immunocompromised patients with r CDI. FMT showed promise for the eradication of antibiotic-resistant bacteria, but further research is warranted.