Phenotypic and Genotypic Characterization of Metallo-Beta-Lactamase and Extended-Spectrum Beta-Lactamase among Enterobacteria Isolated at National Public Health Laboratory of Brazzaville

The improper use of antimicrobials against infectious diseases has allowed microorganisms to develop defense mechanisms that give them insensitivity to these agents. All bacteria are concerned by this phenomenon. This work aimed to assess prevalence of beta-lactamase produced by enterobacterial isolates. Then, disc diffusion, double disc synergy test (DDST) and combined disc test (CDT) were respectively used for antimicrobial resistance, detection of Extended-Spectrum Beta-Lactamases (ESBL) and Metallo-Beta-Lactamases (MBL). bla genes were detected by PCR. A total of 132 enterobacterial strains were studied. Resistance to antibiotic families was observed with a greater frequency than 50%. Gentamicin was the least active beta-lactam antibiotic, with a resistance rate of 88%. 40.9% of strains show an ESBL phenotype and 16.6% were MBL. An overall prevalence of 74% (40/54) and respectively rates of 29.6%, 27.7% and 16.7% for blaSHV, blaCTX and blaTEM genes were observed. SHV, CTX, CTX/SHV/TEM, CTX/TEM, SHV/TEM and CTX/SHV were different ESBL genotypes observed. ESBL-producing enterobacteria isolation worried about the future of antimicrobial therapy in the Republic of Congo. This is a public health problem that requires careful monitoring and implementation of a policy of rational antibiotics use.

Identification of Bacteria Strains Isolated in Urinary Tract Infections and Their Antibiotic Susceptibility at the National Public Health Laboratory, Ouagadougou

Background: Urinary tract infections are still a real public health concern. The aim of this study was to identify the bacteria strains involved in urinary tract infections and to determine their antibiotic resistance profiles. Methods: Two kinds of studies were performed. The retrospective study was carried out for 2 years (from January 2018 to December 2019), and the prospective study was extended over a period of 6 months (from January to June 2020). Isolation and identification of bacteria strains were performed using conventional microbiology techniques. The strains’ resistance profiles were determined by the diffusion method on Mueller-Hinton according to the criteria of EUCAST- 2015. Fourteen (14) antibiotic discs were used depending on the isolated germ. Results: A total of 187 bacterial strains were isolated from 82 men and 105 women. Among the germs identified, 77.54% were Enterobacteriaceae and 13.36% were cocci strains. Non-fermentative gram-negative bacilli accounted for 9.08% of the isolated bacteria. The results showed that the majority of Enterobacteriaceae strains were resistant to beta-lactams: 100% to amoxicillin, 98.75% to amoxicillin + clavulanic acid, 41.76% to ceftriaxone, and 43.14% to ceftazidime. These findings were obtained with fluoroquinolones and aminoglycosides: 50.09% with ciprofloxacin, 54.04% with norfloxacin, and 22.58% with amikacin. 8.75% of the Enterobacteriaceae strains tested were resistant to imipenem. The same trends were observed with non-fer- mentative bacteria. As for the gram-positive bacteria isolated during our study, 13.33% were resistant to vancomycin, 21.05% to gentamicin, 94.12% to penicillin G, 88.89% to ampicillin, 77.78% to cefotaxime, 63.63% to kanamycin, and 52.63% to erythromycin. Conclusion: This study revealed, as in other studies, that Enterobacteriaceae strains remain the most incriminated bacteria strains in urinary tract infections, with a strong resistance to antibiotics. It is important that actions be taken to reduce the incidence of urinary tract infections and mitigate the spread of resistant bacteria.

Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon

1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to December 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission.

Prevalence and Resistance Profile of Muenchen Cefotaximase (CTX-M) Group 1 Extended Spectrum Beta-Lactamase (ESBL)-Producing Uropathogenic Escherichia coli Strains in Dakar, Senegal

Background: Extended-spectrum beta-lactamase (ESBL) producing bacteria are a real public health problem, particularly in Africa. Among these ESBLs, there are the Muenchen Cefotaximase (CTX-M) described all over the world of which the most frequent is the CTX-M of group 1 particularly the CTX-M-15 variant. The objective of this study was to determine the prevalence of CTX-M group 1 ESBL-producing Escherichia coli strains and to test their antibiotics susceptibility profile. Methodology: A retrospective cross-sectional descriptive study was conducted to detect ESBL-secreting Escherichia coli strains by the synergy test. Identification of CTX-M type ESBL from group 1 was performed using the NG-Test CTX-M rapid diagnostic test (NG-Biotech®). Antibiotic susceptibility profile was determined using CA-SFM/EUCAST guidelines 2019. Data entry and statistical analysis were performed with Excel version 2010 and SPSS 20.0 respectively. Results: Eighty-two ESBL-producing Escherichia coli strains were tested. A group 1 CTX-M ESBL was detected in 75.6% of the strains (n = 62). These strains were highly resistant to cefotaxim (100%), aztreonam (100%), ceftazidim (85.4%) and cefepim (66.1%). They were also resistant to quinolones, gentamycin and sulfadoxine-trimethoprim combination. However, these strains showed sensitivity to ertapenem (100%), cefoxitin (69.3%), tigecyclin (66%), and amikacin (66.1%). The combination of piperacillin and tazobactam was active on 30.6% of the strains against 6.4% for the combination of amoxicillin and clavulanic acid. Conclusion: The CTX-M type ESBL of group 1 was present in the majority of ESBL-producing Escherichia colis trains. Despite the production of this enzyme conferring resistance to most beta-lactam antibiotics, some antibiotics remain active to treat infections caused by these germs.

Evolution of Biochemical, Hematological, Inflammatory and Immunological Markers among Person Living with HIV-1 on ART in Burkina Faso

In Human immunodeficiency virus infected (HIV+) patients, deregulation of regulatory T (Treg) cells can be deleterious for the development of an efficient anti-HIV specific immune response with an inappropriate immune activation despite anti-retroviral therapy (ART). In addition, infection and ART have the potential to cause hematological and biochemical abnormalities that can lead to the discontinuation of ART. The aim of this study was to assess hematological, biochemical and immunological abnormalities in HIV+ patients’ naïve to ART and 6 months after ART initiation. In a cross-sectional study, 11 HIV+ patients and 09 healthy individuals (control group) were voluntarily recruited. At inclusion, blood samples were taken before administration of ART. All hematological, biochemical, immunological parameters and viral load were measured and assessed at inclusion (M0) and three and/or six months later (M3, M6). Higher level of white blood cells and CD4+ T lymphocytes (p = 0.032, 0.038 respectively) were observed in HIV+ patients. ART also had significantly effect on the level of red blood cells (p = 0.04) and Hb (p = 0.015). The inflammatory markers, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) that were significantly increased by HIV infection, tended to decrease for ESR and revert to levels similar to those of control for CRP. Analysis of CD4+CD25+ cells and CD4+Foxp3+CD25+ showed significantly elevated levels of activated form of all CD4+ cells and Treg cells. Interestingly, six months after initiation of ART, the average percentage of CD4+CD25+ was not significantly different from control group (p = 0.382). Our study provides information about the evolution of the activated form of all CD4 cells and Treg cells and points out the necessity to monitor hematological and biochemical parameters in order to detect and prevent toxicity, improve the quality of life and reduce the risk of mortality.

Antibiotics Resistance Profile of Bacillus cereus Strains Isolated from Soil and Pepper in Brazzaville

Introduction: Bacillus cereus and spores produced in various ecological niches are responsible for toxic infections in humans. This study is conducted to determine the antibiotics resistance profile of B. cereus strains isolated from soil and pepper consummated in Brazzaville. Methodology: An antimicrobial susceptibility test of 16 B. cereus strains from soil and peppers was performed using 11 antibiotics by the Kirby-Bauer’s diffusion on disc method. Results: Results revealed 100% (16/16) of resistance in penicillin G, amoxicillin, ceftazidime, rifampicin, and colistin, also 18.75% (3/16), 11.76% (2/16), and 18.75% (3/16) of resistance in doripenem, vancomycin and chloramphenicol respectively. In addition, we have observed 100% (16/16), 81.25% (13/16), 76.47% (13/16), 35.29% (5/16), 35.50% (6/16), and 12.5% (2/16) of sensitivity to line-zolid, tigecycline, ciprofloxacin, vancomycin, doripenem and chloram-phenicol respectively. However, all strains have been multidrug resistant (MDR) to betalactams, polypeptides, and ansamycins. Moreover, 7 strains (43.75%) have been variably multiresistant. One strain, Ri10 has been resistant to beta-lactams, polypeptides, ansamycins, cyclins and glycopeptides. No strain was ultraresistant (XDR) or largely insensitive (PDR) to different antibiotics. Conclusion: This study reveals that 51% of strains have been resistant to antibiotics, 32% are sensitive, and 17% have intermediate resistance. These results partly explain the high rate of gastroenteritis observed in Brazzaville due to food poisoning.

Higher IL-8 Response to <i>Mycobacterium tuberculosis</i>Antigens in Women above 40 Years

Objective: Circulating levels of sex hormones vary with age. Moreover, there is emerging evidence supporting that sex hormones have an influence on the immune response of women. Here, we investigated age-associated levels of sex hormones and Mycobacterium tuberculosis (Mtb) specific cytokines response in women. Design: Using immunoassay methods, we have measured and compared secretion levels of E2, P4 and Mtb specific secretion of 11 cytokines including Granulocyte-macrophage colony-stimulating factor (GM-CSF), Interferon gamma (IFN-γ), Interleukin 1 beta (IL-1β), IL-10, IL-12 (p70), IL-2, IL-4, IL-5, IL-6, IL-8, and Tumor necrosis factor (TNF-α) in forty-two (42) HIV-negative females. Results: Estradiol (E2) and progesterone (P4) levels were significantly higher in younger women irrespective of their LTB status (p < [0.0001 - 0.05]). Mtb IL-8 specific response was significantly higher in women above 40 years old than in women under 40 years old. Conclusion: In premenopausal women, there is an increase in the pro-inflammatory cytokine IL-8 secretion in response to Mtb-antigen. This observation suggests an underlying link between the pro-inflammatory cytokine and age associated hormonal changes, which may have implications on the course of tuberculosis infection women.

Assessment of Air Quality in Brazzaville: Measurement of Some Automobile Pollutants

Atmospheric pollution is currently a real public health problem because of its potentially harmful effects on the environment as well as on human health. Several studies conducted in America, Europe, Asia, and Africa have established a significant link between air pollution and cancer, infertility, cardiovascular and respiratory morbidity, and mortality. This study aims to measure some automotive pollutants (CO, CO2, NO2, and SO2) by a selective and colorimetric method using a measurement system on Dräger reagent tubes coupled to a Dräger Accuro sampling pump in order to do a quantitative assessment of air quality in the nine districts of Brazzaville. The results obtained during this study revealed high concentration levels of pollutants (CO, CO2, NO2, SO2), all above the standards recommended by the WHO. The results obtained during this study made it possible to categorise Brazzaville as a polluted city.

Exposure to Automobile Pollutants and Sperm Quality among Mechanics in Brazzaville (Congo)

Atmospheric pollution is today at the heart of all debates because of its potentially harmful effects on the environment, the climate, and human health;it currently constitutes a real public health problem. However, the increase in infertility around the world has led scientists to look for a link between air pollution and fertility. This study consisted of evaluating the short-term influence of automobile pollution on the semen parameters of mechanics in Brazzaville. A cross-sectional, analytical, prospective study between two groups (G1, exposed people and G2, unexposed people) was carried out in Brazzaville on 228 patients, i.e., G1 with 76 subjects and G2 with 152 subjects, between June 2020 and September 2022, a period of 27 months, in order to evaluate, on the one hand, the quality of sperm in men exposed to automobile pollution according to WHO recommendations and, on the other hand, the quality of the air by a colorimetric method, punctual on a Dräger tube coupled with a Dräger Accuro pump. The concentrations of automotive pollutants measured (CO, CO2, NO2, SO2) during this study were all above the 2021 air quality standards required by WHO. These results made it possible to establish a statistically significant link between air pollution and abnormal spermogram parameters, notably mobility, count, and morphology for the spermocytogram. Exposures to automobile pollutants can influence sperm quality, which is consistent with the results of our study. We observed an alteration in the morphology, mobility, and concentration of spermatozoa.

Performance of the procedure for ultra-rapid extraction and loop-mediated isothermal amplifcation (PURE-LAMP) method to detect malaria in Haiti

Background Malaria continues to cause burden in various parts of the world.Haiti,a Caribbean country,is among those aiming to eliminate malaria within a few years.Two surveys were conducted in Haiti during which we aimed to evaluate the performance of the simple and rapid procedure for ultra-rapid extraction-loop-mediated isothermal amplifcation(PURE-LAMP)method with dried blood spots as an alternative diagnostic method for malaria in the context of low to very low rates of transmission.Methods Febrile and afebrile people were recruited from three administrative divisions within Haiti:Nippes,Sud and Grand’Anse,during the summers of 2017(early August to early September)and 2018(late July to late August).Their blood samples were tested by microscopy,rapid diagnostic tests(RDT),PURE-LAMP and nested PCR to detect Plasmodium infection.Sensitivity,specifcity,positive and negative predictive values and kappa statistics were estimated with the nested PCR results as the gold standard.Results Among 1074 samples analyzed,a positive rate of 8.3%was calculated based on the nested PCR results.Among febrile participants,the rates in 2017 and 2018 were 14.6%and 1.4%,respectively.Three positives were detected among 172 afebrile participants in 2018 by PURE-LAMP and nested PCR,and all three were from the same locality.There was no afebrile participants recruited in 2017.The PURE-LAMP,RDT and microscopy had respective sensitivities of 100%,85.4%and 49.4%.All of the testing methods had specifcities over 99%.Conclusions This study confrmed the high performance of the PURE-LAMP method to detect Plasmodium infection with dried blood spots and recommends its use in targeted mass screening and treatment activities in low endemic areas of malaria.