Salmonellosis is one of the most common and widely distributed group of enteric diseases in the world today. It causes high mortality and morbidity especially in developing countries. This study was aimed at identifying the factors that predispose people to salmonellosis. In addition the study was meant to isolate Salmonella, and determine its antimicrobial sensitivity and test the effectiveness of water treatment for the control of salmonellosis. To identify the predisposing factors of salmonellosis, a questionnaire was used. For the isolation of Salmonella, a total of 630 samples were collected from raw cows’ milk, sheep and cattle intestinal wastes, raw fruit and vegetable salads, waste water, water sources and water that had been treated by the study population through boiling, chlorination and filtration. Samples were also collected from water that was treated through solar disinfection. The samples were pre-enriched using peptone water then selectively enriched using Selenite F broth and incubated at 37 oC for 24 hrs and subcultured in xylose lysine desoxycholate (XLD) agar and Salmonella- Shigella agar in five replicates. Typical Salmonella colonies were confirmed by biochemical test using API E-20 and the species serotyped. The isolated serovars were tested against seven antibiotics; cephalexin, nalidixic acid, chloramphenicol, ciprofloxacin, gentamicin, amoxycillin and sulfa-trimethoprim. The results were analyzed by the use of chi-square test, correlation test and Anova using Statistical Package for Social Sciences (SPSS version 11.50) software. Level of education, occupation, method of food storage, cleaning of kitchen utensils, hand washing, human waste disposal, animal wastes, presence or absence of sewers, waste water, tap water, river water and water treatment were significantly associated with salmonellosis while sex, well water and method of water treatment were not. There was no significant difference between the microbial load of Salmonella isolates from milk, sheep and cattle intestinal wastes, waste water, fruits and vegetable salads in Maili 5, Bahati and Kabatini. However, River Kandura’s water mean Salmonella isolates varied significantly from upstream to downstream. Of the 105 Salmonella isolates Salmonella enterica serovar Typhimurium were (45.7 %), S. enterica serovar Typhi (22.9 %), S. enterica serovar Enteritidis (21.9 %) and S. enterica serovar Dublin (9.5 %). All the serovars were susceptible to gentamicin.
Table of Contents
CHAPTER ONE: INTRODUCTION
1.1 Background of the study
1.2 Problem statement and justification
1.3 Research questions
1.4 Study hypotheses
1.5 Objectives of the study
1.5.1 General objective
1.5.2 Specific objectives
CHAPTER TWO: LITERATURE REVIEW
2.1 Global overview of salmonellosis
2.2 Isolation of Salmonella
2.2.1 Raw cow milk
2.2.2 Animal intestinal wastes
2.2.3 Fruits and vegetable salads
2.2.4 Waste water
2.2.5 Water source in Nakuru North Sub-County
2.2 Methods of water treatment
2.3.1 Boiling of water
2.3.2 Chlorination
2.3.3 Filtration
2.3.4 Solar disinfection
2.4 Antimicrobial resistance
2.5 Global trends in resistance pattern
CHAPTER THREE: MATERIALS AND METHODS
3.1 Study area
3.2 Sample size
3.3 Identification of predisposing factors of salmonellosis
3.4 Sample collection
3.5 Salmonella isolation procedure
3.6 Analytical Profile Index (API 20E)
3.7 Serological test
3.8 Solar disinfection
3.9 Antimicrobial sensitivity testing
3.10 Data management and analysis
CHAPTER FOUR: RESULTS
4.1 Predisposing factors of salmonellosis
4.1.1 Ages of the respondents
4.1.2 Education level of the respondents
4.1.3 Occupation level of the respondents
4.1.4 Sex of the respondents
4.1.5 Storage of food
4.1.6 Cleaning of kitchen utensils
4.1.7 Hand washing practices
4.1.8 Human waste disposal
4.1.9 Animal waste disposal
4.1.10 Sewerage in the area
4.1.11 Waste water disposal
4.1.12 Sources of water for use in the households
4.1.13 Water treatment in the households
4.1.14 Methods of water treatment
4.2 Isolation of Salmonella
4.2.1 Salmonella load of raw milk
4.2.2 Salmonella load from animal intestinal wastes
4.2.2.1 Salmonella load of sheep intestinal wastes
4.2.2.2 Salmonella load of cattle intestinal wastes
4.2.3 Salmonella load of raw fruits and vegetable salads
4.2.4 Salmonella load of waste water
4.2.5 Salmonella load of water sources
4.2.5.1 Salmonella load of water running in community taps
4.2.5.2 Salmonella load of water samples from river Kandutura
4.3 Salmonella load of Boiled, chlorinated and filtred water
4.4 Solar disinfection
4.5 Serotyping of Salmonella
4.6 Antimicrobial sensitivity test
CHAPTER FIVE: DISCUSSION, CONCLUSION AND RECCOMMENDATIONS
5.1 Discussion
5.1.1 Predisposing factors of salmonellosis infections
5.1.2 Salmonella load of samples
5.1.3 Effectiveness of water treatment methods
5.1.4 Serotyping of Salmonella
5.1.5 Antimicrobial resistance patterns of Salmonella
5.2 Conclusion
5.3 Recommendations
Research Objectives and Themes
This thesis investigates the prevalence, predisposing factors, and antimicrobial sensitivity of Salmonella within the Nakuru North Sub-County, while assessing the efficacy of local water treatment methods in controlling salmonellosis transmission.
- Identification of socio-demographic factors predisposing populations to salmonellosis.
- Quantitative analysis of Salmonella load across various food and environmental samples (milk, meat, water).
- Evaluation of point-of-use water treatment effectiveness, including boiling, chlorination, filtration, and solar disinfection.
- Determination of antimicrobial susceptibility patterns in isolated Salmonella serotypes to guide public health interventions.
Excerpt from the Book
2.2.2 Animal intestinal wastes
Ruminants, such as cattle and sheep, are natural reservoirs for Salmonella. Salmonella is mostly present within the rumen of these animals and is shed through fecal matter, hence ending up in water sources and farms. Previous studies by Reicks et al. (2001) (73 %) and Kunze et al. (2007) (30.3 %) have reported differing proportions of Salmonella in intestinal samples. Cross contamination can begin during transport with other animals via direct body contact or indirectly via contact surfaces (McEvoy, 2004). Contaminants can be transferred to the digestive system during slaughter by initial cuts with knife and when the animal is feeding (Reid et al., 2000).
These contaminations have the risk of contaminating the entire production chain of the slaughter house. Several factors influence animal intestine contamination. These factors include but are not limited to transport conditions and duration, herd lot mingling, drinking water systems, hide cleanliness, and feed withdrawal, automated hide puller/debunging, extent/efficiency of abattoir cleaning and operative hygiene practices (McEvoy, 2004). Various Salmonella strains have been isolated from different animals. However, sheep and cattle are more prevalent carriers than nonruminant animals (Hussein, 2006). Due to the innate presence of Salmonella in the intestines, cattle hides have been identified as a central source of microbial contamination when animals lick one another or themselves (Hussein, 2006) especially on rainy season compared to dry season. In another study that investigated the seasonal prevalence of non-typhoidal Salmonella, it was established that the bacteria are more prevalent during the rainy season than in the dry season (Piddock, 2001).
Summary of Chapters
CHAPTER ONE: INTRODUCTION: This chapter provides an overview of Salmonella as a global pathogen and establishes the specific research problem and objectives regarding its prevalence in Nakuru North Sub-County.
CHAPTER TWO: LITERATURE REVIEW: This chapter reviews global trends in salmonellosis, common isolation sources, and existing water treatment methodologies and antimicrobial resistance patterns.
CHAPTER THREE: MATERIALS AND METHODS: This chapter details the study area, sampling strategies for 630 specimens, laboratory isolation procedures, and the analytical frameworks used for results evaluation.
CHAPTER FOUR: RESULTS: This chapter presents data on predisposing factors and contamination levels across the studied samples, highlighting associations between demographic variables and disease risk.
CHAPTER FIVE: DISCUSSION, CONCLUSION AND RECCOMMENDATIONS: This chapter interprets the findings in the context of existing literature, concludes on the effectiveness of local control measures, and proposes public health policy improvements.
Keywords
Salmonellosis, Salmonella enterica, Nakuru North Sub-County, Antimicrobial resistance, Water treatment, Chlorination, Solar disinfection, Food safety, Public health, Serotyping, Enteric pathogens, Kenya, Bacterial load, Contamination, Epidemiology
Frequently Asked Questions
What is the core focus of this research?
The research focuses on the prevalence of Salmonella and the factors contributing to the spread of salmonellosis in the Nakuru North Sub-County of Kenya.
What are the primary areas investigated?
The study examines predisposing social factors, bacterial load in food and water sources, the efficacy of water treatment methods, and the antibiotic sensitivity of isolated strains.
What is the main objective of the thesis?
The main objective is to identify factors predisposing people to salmonellosis, isolate the bacteria from various sources, determine antimicrobial sensitivity, and assess water treatment effectiveness.
Which scientific methodology was employed?
The study utilized a cross-sectional approach involving a structured questionnaire for 90 respondents and the analysis of 630 laboratory samples using microbiological enrichment, biochemical testing (API 20E), and antibiotic disk diffusion assays.
What does the main body of the work address?
The work addresses the isolation and quantification of Salmonella from raw milk, animal wastes, produce, and different water sources, while evaluating standard water treatment techniques used in the community.
What are the key terms that characterize this work?
The key terms include Salmonella, antimicrobial resistance, water treatment, public health, Nakuru North Sub-County, and epidemiological control.
How effective was solar disinfection in this study?
The study found that solar disinfection is an effective method for water treatment when there is continuous exposure to sunlight for at least 3 to 5 hours.
What did the antimicrobial sensitivity tests reveal?
The tests revealed that Salmonella isolates were highly sensitive to gentamicin but showed significant resistance to antibiotics such as nalidixic acid.
Is there a link between education levels and infection risk?
Yes, the study established a significant association, indicating that lower levels of education correlate with higher risk factors for salmonellosis transmission due to variations in hygiene knowledge.
- Citar trabajo
- Paul Waithaka (Autor), 2014, Predisposing Factors, Isolation, Sensitivity to Antibiotics and Control Methods of Salmonellosis in Nakuru North Sub-County, Kenya, Múnich, GRIN Verlag, https://www.grin.com/document/286951
