Antimicrobial resistance in Madagascar: a review of the current situation and challenges

Antimicrobial resistance (AMR) is a growing public health threat worldwide occurring in a wide range of pathogenic bacteria. It is encouraging that governments of countries around the world are beginning to pay attention to the issue of AMR that serves to undermine the future of modern medicine. However, each country solution approaches to this issue will differ in terms of magnitude and response capacity. Madagascar is a low-income country and one of the poorest countries in the world with poor environmental hygiene practices and easy availability of antimicrobial drugs without medical prescription. These particular contexts certainly influence the spread of multi-drug resistant bacteria. This review presents reported data on AMR from 2001 to 2018 in Madagascar among the World Health Organization (WHO) priority human pathogens, and determined the scope and magnitude of the AMR problems in the particular context of this low-income country, which could help in formulating effective response strategies for control of AMRs in Madagascar. Key words: Antimicrobials, Madagascar, Multi-drug resistance, Prevalenc

Evaluation of methicillin-resistant Staphylococcus aureus nasal carriage in Malagasy veterinary students

Purpose: Populations that are frequently in contact with animals such as veterinary students have been demonstrated to be at risk of MRSA carriage.Thus, it is relevant to generate baseline data in MRSA nasal carriage and multidrug resistance among Malagasy veterinary students (Madagascar).Method: A cross-sectional study was carried out among veterinary students coming for laboratory training. After their wise consent, nasal swabs of the anterior nares were carried out; and S. aureus was isolated by selective chromogenic culture. They were then assessed for antimicrobial susceptibility.Results: Nasal swabs of 155 Malagasy veterinary students (Sex-ratio M/F: 0.91), enabled to isolate 30 (19, 35%) S. aureus strains, among which 14 (46, 66 %) were méthicillin-resistant (MRSA). Risk factors analysis revealed that history of hospitalization, recent antibiotic intake and frequent contact with animals and livestock workers/veterinarians increase the risk of MRSA nasal carriage. Among MRSA nasal isolates, a high rate of multidrug resistance and particularly an intriguing resistance to gentamycin (20%) and vancomycin (7.14%) were observed.Conclusion: These results suggest that MRSA is spreading in Malagasy community requiring a strategic policy against multidrug resistant strains.Keywords: Madagascar, MRSA, Risk factors, Veterinar

Evaluation of Phenotypic Variations in the Antibiotics Sensitivity of Escherichia Coli by Repeated Exposure

Enterobacteriaceae, in particular Escherichia coli, are habitual residents of the gastrointestinal tract, capable of causing a large number of infections. The MIC varies according to the bacterial strains and the antibiotics used, hence the need to carry out antibiotic sensitivity tests. The objective of this study is to evaluate the behavior of Escherichia coli after repeated exposure to the same antibiotic to demonstrate a possible correlation between excessive intake of antibiotics and bacterial resistance. A prospective and descriptive study was carried out in the Laboratory of Microbiology of Fundamental and Applied Biochemistry (Faculty of Sciences Antananarivo) during the month of November 2019. The strains studied were the reference strain Escherichia coli ATCC 25922 provided by the Laboratory and two clinical strains from the Microbiology Laboratory of the Joseph Ravoahangy Andrianavalona University Hospital Center (CHU JRA) Antananarivo. Repeated exposure to Tobramycin and Ofloxacin of these strains were performed. The results of our study showed that most E. coli is exposed to the antibiotic, the more it develops resistance. The evolution of E. coli's sensitivity is different in the presence of Tobramycin with MICs up to 4 times the starting value while in the presence of Ofloxacin, the MIC increases to 125 times the initial value. This difference may be due to the different target of the antibiotic which causes the bacteria to develop variable mechanisms to escape it. Key words: E. coli - MIC - antibiotics - repeated exposur

Evaluation of Phenotypic Variations in the Antibiotics Sensitivity of Escherichia Coli by Repeated Exposure

Enterobacteriaceae, in particular Escherichia coli, are habitual residents of the gastrointestinal tract, capable of causing a large number of infections. The MIC varies according to the bacterial strains and the antibiotics used, hence the need to carry out antibiotic sensitivity tests. The objective of this study is to evaluate the behavior of Escherichia coli after repeated exposure to the same antibiotic to demonstrate a possible correlation between excessive intake of antibiotics and bacterial resistance. A prospective and descriptive study was carried out in the Laboratory of Microbiology of Fundamental and Applied Biochemistry (Faculty of Sciences Antananarivo) during the month of November 2019. The strains studied were the reference strain Escherichia coli ATCC 25922 provided by the Laboratory and two clinical strains from the Microbiology Laboratory of the Joseph Ravoahangy Andrianavalona University Hospital Center (CHU JRA) Antananarivo. Repeated exposure to Tobramycin and Ofloxacin of these strains were performed. The results of our study showed that most E. coli is exposed to the antibiotic, the more it develops resistance. The evolution of E. coli\u27s sensitivity is different in the presence of Tobramycin with MICs up to 4 times the starting value while in the presence of Ofloxacin, the MIC increases to 125 times the initial value. This difference may be due to the different target of the antibiotic which causes the bacteria to develop variable mechanisms to escape it. Key words: E. coli - MIC - antibiotics - repeated exposur

Natural Compounds Inhibiting <em>Pseudomonas aeruginosa</em> Biofilm Formation by Targeting Quorum Sensing Circuitry

The biofilm lifestyle mode certainly represents one of the most successful behaviors to facilitate bacterial survival in diverse inhospitable environments. Conversely, the ability of bacteria to develop effective biofilms represents one of the major obstacles in the fight against bacterial infections. In Pseudomonas aeruginosa, the biofilm formation is intimately connected to the quorum sensing (QS) mechanisms, a mode of cell-to-cell communication that allows many bacteria to detect their population density in order to coordinate common actions. In this chapter, we propose an overview (i) on P. aeruginosa QS mechanisms and their implication in biofilm formation, and (ii) on natural products that are known to interfere with these QS mechanisms, subsequently disrupting biofilm formation. The concluding remarks focus on perspectives of these compounds as possible antibiotherapy adjuvants

A STUDY ON RECTAL CARRIAGE OF MULTIRESISTANT GRAM-NEGATIVE BACILLI IN CHILDREN ATTENDING PEDIATRIC HOSPITAL AMBOHIMIANDRA, MADAGASCAR

Introduction:&nbsp;Gram-negative bacilli are often responsible for rectal colonization in children. These bacilli normally sensitive to third generation cephalosporins (3GC) have acquired disturbing antibiotic resistance in recent years, hence the interest of our study. The aims are to monitor the epidemiological evolution resistance of Enterobacteriaceae with antibiotics in particular β-lactams, estimate the prevalence of enterobacteria responsible for rectal colonization and their resistance to 3GC.&nbsp;Material and methods: This is a descriptive prospective study of&nbsp;Enterobacteriaceae&nbsp;in children attending Ambohimiandra Hospital for a period of 3 months (from 01 August to 31 October 2015). We have done a rectal swab of all the children whom we have parental consent. The samples were processed at the Laboratory of Medical Biology Faravohitra. The parameters studied are the antecedent of therapy antibiotic, notion of recent hospitalization and the results of microbiological examinations.&nbsp;Results:&nbsp;Of the 55 bacteriological samples obtained, 39 strains of&nbsp;Enterobacteriaceae&nbsp;were isolated,&nbsp;Escherichia coli&nbsp;(n = 12),&nbsp;Enterobacter cloacae&nbsp;(n = 13),&nbsp;Citrobacter spp&nbsp;(n = 1),&nbsp;Salmonella spp.&nbsp;(N = 5) and&nbsp;Shigella spp&nbsp;(n = 2),&nbsp;Proteus mirabilis&nbsp;(n = 1). Six isolated strains (50%) of&nbsp;Escherichia coli&nbsp;showed resistance to ceftriaxone, of which 4 (33.33%) produced ESBL.&nbsp;Conclusion: Gram-negative bacilli responsible for colonization of the digestive tract have several resistances to β-lactams, in particular 3GC, by the production of enzymes (Expanded spectrum beta-lactamase or ESBL and cephalosporinase or CASE) which hydrolyze these antibiotics. Measures to combat the spread of these phenomena resistance must be implemented in the Malagasy community to limit them. KEYWORDS:&nbsp;Rectal porous; Gram negative bacillus; ESBL; Multiresistence

SEROPREVALENCE OF HIV, HBV, HCV, SYPHILIS AMONG DONORS OF BLOOD AT THE NATIONAL CENTER OF BLOOD TRANSFUSION ANTANANARIVO IN 2014

Introduction: Currently, routine screening for HIV, hepatitis B and C and syphilis is done in most blood banks in the world.&nbsp;Methods: We conducted a prospective descriptive study at the National Blood Transfusion Center (CNTS) Antananarivo for a period of 7 months from January to July 2014, which aims to assess the socio-clinical factors accompanying ineligibility of blood products and to determine the seroprevalence of HIV, hepatitis B, C and syphilis of the blood donors who have spent at CNTS HU JRA Antananarivo during this period. All donors who have abnormal results of microbiological examinations were included. The parameters used and studied were age, sex, marital status, blood and results microbiological examinations for HIV, hepatitis B, C, and syphilis. The prevalence of blood donors who presented a serological abnormality is 3.95% with a predominance of donors with hepatitis B (72.93%) followed by syphilis (18.29%) of the hepatitis C (6.95%) and HIV (1.80%) and a predominance of young people.&nbsp;Conclusion:&nbsp;At the CNTS Antananarivo, the HBV is the main definitive reason for exclusion of these donors. This high prevalence is a real public health problem for the country\u27s health authorities. The search for maximum safety in blood transfusion through firstly a better selection of blood donors by implementing a policy of strong loyalty and other early diagnosis of major diseases transmissible by blood and likely to infect the recipient. KEYWORDS:&nbsp;Antananarivo; Blood donor; Microbiology; Seroprevalence

SEROPREVALENCE OF HIV, HBV, HCV, SYPHILIS AMONG DONORS OF BLOOD AT THE NATIONAL CENTER OF BLOOD TRANSFUSION ANTANANARIVO IN 2014

Introduction: Currently, routine screening for HIV, hepatitis B and C and syphilis is done in most blood banks in the world.&nbsp;Methods: We conducted a prospective descriptive study at the National Blood Transfusion Center (CNTS) Antananarivo for a period of 7 months from January to July 2014, which aims to assess the socio-clinical factors accompanying ineligibility of blood products and to determine the seroprevalence of HIV, hepatitis B, C and syphilis of the blood donors who have spent at CNTS HU JRA Antananarivo during this period. All donors who have abnormal results of microbiological examinations were included. The parameters used and studied were age, sex, marital status, blood and results microbiological examinations for HIV, hepatitis B, C, and syphilis. The prevalence of blood donors who presented a serological abnormality is 3.95% with a predominance of donors with hepatitis B (72.93%) followed by syphilis (18.29%) of the hepatitis C (6.95%) and HIV (1.80%) and a predominance of young people.&nbsp;Conclusion:&nbsp;At the CNTS Antananarivo, the HBV is the main definitive reason for exclusion of these donors. This high prevalence is a real public health problem for the country's health authorities. The search for maximum safety in blood transfusion through firstly a better selection of blood donors by implementing a policy of strong loyalty and other early diagnosis of major diseases transmissible by blood and likely to infect the recipient. KEYWORDS:&nbsp;Antananarivo; Blood donor; Microbiology; Seroprevalence

Malagasy traditional treatments of infectious plant diseases exert anti-virulence activities against pseudomonas aeruginosa and Ralstonia solanacearum

peer reviewedTraditional Malagasy farmers have developed a range of biological methods to restrict plant diseases without reliance on external or synthetic inputs. Five common Malagasy traditional practices demonstrated to be efficient against potato crop bacterial disease in experimental fields have been investigated for their antibacterial (i.e. bacteriostatic and bactericidal effects) and anti-virulence (i.e. antiquorum sensing and anti-biofilm) activities against two phytopathogens, Pseudomonas aeruginosa and Ralstonia solanacearum. Results show that polar (methanolic) extracts of recipes exert anti-virulence activities rather than bacteriostatic and/or bactericidal activities. Indeed, three recipes (R5, R7 and R9) reduce the expression of QS-dependent virulence factors whereas only recipe (R5) exhibit antibiofilm activities without affecting bacterial growth. R4 and R6 were not active, suggesting other bacterial targets and/or other bioactivity properties. Innovative approaches, inspired from ancestral practices, should be considered in the struggle against infectious diseases to limit the overuse of antibiotics for controlling infectious plant diseases and to reduce the overspread of multidrug resistant bacteria