ABSTRACT

 Salmonellosis and shigellosis are still global health problem, especially, in developing countries where poor sanitation, lack of clean water supply and proper sewage disposal system exist. The emergence of increased antimicrobial susceptibility to Salmonella and Shigella spp are global challenges particularly in developing countries like Nigeria where misused antibiotics by human beings occur. This study aims to investigate the antibiotics susceptibility pattern of these microbes. A total of 60 stool samples were isolated from healthy students of Michael Okpara University of Agriculture Umudike and cultured on Salmonella-Shigella agar for screening of microbes and the antibiotic susceptibility pattern of the isolates were determined following standard bacteriological method.  Antibiotic were selected for the test (Amoxicilin, Ampicilin, Nalixidic acid, Ciprofloxacin, Gentamicin, Chloramphenicol and Tetracycline). 9 (15%) Samonella and 7(11.67%) Shigella was isolated from stool samples of both male and female students. Sensitivity of Salmonella was 100% to Chloramphenicol, 60% to Nalixidic acid, Ampicillin and Gentamicin, 40% to Ciprofloxacin and Tetracycline, and 0% Amoxicillin in female. And 75% to Amoxicillin, Nalixidic acid and Gentamicin, 100% to Ciprofloxacin and Chloramphenicol, 25% to Ampicillin and 0% to Tetracycline in male. Shigella had sensitivities of 75% Amoxicillin, Nalixidic acid and Gentamicin and Tetracycline in female and 100% to Nalixidic acids, Chloramphenicol and Ciprofloxacin, 33.3% to Amoxicillin and Ampicillin, 0.0% to Gentamycin and Tetracycline. However, isolates of Samonella and Shigella were 100% susceptible to Ciprofloxacin, Chloramphenicol and Nalixidic acid. This study revealed that isolates of Shigella and Salmonella showed high rate of drug resistance  to commonly used   antibiotics and all isolates were susceptible to Ciprofloxacin and Chloramphenicol. Therefore Ciprofloxacin and Chloramphenicol can be used as drugs of choice for the treatment of Shigellosis and Salmonellosis.     

TABLE OF CONTENT

Title page

Certification i

Dedication ii

Acknowledgement iii

Table of content iv

List of tables viii

Abstract ix

CHAPTER ONE

1.0 Introduction 1

1.1 Aims and objectives 3

CHAPTER TWO

2.0 Literature review                                                                                                              4

2.1 Morphology and culture 4

2.2 Characteristics of the genius Salmonella and Shigella 5

2.3 Geographical distribution 7

2.4 Pathogenicity of the genus Salmonella 7

2.4.1 Enteric fever 8

2.4.2 Gastroenteritis 8

2.5  Pathogenicity of genus Shigella 9

2.6 Transmission of salmonellosis and shigellosis 10

2.7 Clinical signs and symptoms of Salmonella infection 10

2.8 Clinical signs of Shigella infection 11

2.9 Prevention and treatment 11

2.9.1 Prevention 11

2.9.2 Treatment 12

2.10 Antibiotic susceptibility and resistance 13

2.11 Classificaion of antibiotics 14

2.12 Mechanism of action of antibiotics 16

2.12.1 Inhibition of cell wall synthesis (Beta- lactams) 16

2.12.2 Inhibition of cell function 17

2.12.3 Inhibition of protein synthesis 17

2.12.4 Inhibition of nucleic acid synthesis 18

2.12.5 Inhibition of other metabolic processes (anti metabolites) 18

CHAPTER THREE

3.0 Materials and methods 19

3.1 Samples and samples/study population 19

3.2 Specimen collection 19

3.3 Sterilization of glass wares 19

3.4 Preparation of culture media 19

3.5 Preparation of innoculum size 20

3.6 Identification test 20

3.6.1 Gram staining 20

3.7 Biochemical test 21

3.7.1 Catalase test 21

3.7.2 Indole production test 21

3.7.3 Coagulase test 21

3.7.4 Oxidase test 22

3.7.5 Urease test 22

3.7.6 Citrate utilization test 22

3.7.7 Methyl red test 23

3.7.8 Voges prokauer test 23

3.7.9 Motility test 23

3.9 Antibiotics susceptibility test 23

3.9.1 Reading of inhibition 24

CHAPTER FOUR

4.0 Results 25

CHAPTER FIVE

5.0 Discussion, conclusion and recommendation 31

5.1 Discussion 31

5.2 Conclusion 33

5.3 Recommendation 33

REFERENCES