Isolation And Characterization Of Vibro Cholerae From A River Source In Nwangele Local Government Area Of Imo State

ABSTRACT

Water is life and has a profound effect on human health. Vibrio cholerae is autochthonous in aquatic environment and is an important human waterborne pathogen causing cholera. This study was designed to determine the presence of Vibrio cholerae in some water sources in Nwagele, Nigeria. A total of 207 water samples were collected from various water sources located in Nwagele Local Government Area of Imo State and cultured on thiosulphate citrate bile saltsucrose agar with prior enrichment on alkaline peptone water. Presumptive isolates were identified and characterized using both conventional biochemical method and identification kit. Isolates were serotyped using Vibrio cholerae antisera kit and confirmed by PCR to detect presence of rfbO1, rfbO139 and ompW genes. Overall, V. choleraewas predominant in river (33.3%) followed by well (4.9%) and least predominant in street vended water (2.7%). None was isolated from borehole and pipe borne water. Water samples from Nwangele LGA most contaminated with an occurrence of 3.2%, while the least contaminated water samples were from Nwagele city (1.5%). V. cholerae of the non O1/ non O139 serogroup were isolated from well, river and street vended water with a prevalence of 2.4% in Imo State. Results of this study suggest that the use of PCR targeting ompW species specific gene of V. cholerae in combination with the conventional method would be an important tool in proper identification of V. cholerae.

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF STUDY

Water is a necessity for life and an adequate, safe and accessible supply is of paramount importance [WHO, 2000].The impact of water on health is associated with unwholesome sources contaminated with faeces (from humans or animals) containing pathogenic microorganisms [Mara and Horan, 2003., WHO, 2011b., Fawell and Nieuwenhuijsen 2003].The quality of drinking water is closely associated with human health and providing safe drinking water is a major public health priority [semenza etal., 1998].Traditionally, water has been considered to be the most important vehicle for cholera transmission [CDC, 1994]. Vibrio cholerae is a gram-negative bacterium of the family Vibrionaceae and is known worldwide as the etiological agent of cholera [Willey et a/., 2008]. Over 200 serogroups of V. cholerae are known of which only 01 and O139 serogroups have been associated with the diarrhoeal disease generally known as cholera [Gaffga et al., 2007]. All other serogroups termed non-01/non 0139 are reported as causative agents of sporadic and localized outbreaks of a cholera-like disease [Eihadi et al., 2012].V. choleraels found mostly in aquatic environment; water therefore plays an important role in the transmission and epidemiology of cholera [Tamrakar et al., 2009]. Monitoring this bacterium in water sources from Nwangele is therefore important [Choopun etal., 2002].

Conventional cultural methods currently used for diagnosis of V. cholera remains the gold standard [Alam et al., 2012]. It involves selective pre-enrichment of samples in alkaline peptone water (APW), plating onto thiosulphate citrate bile salt sucrose (TCBS) agar and followed by morphological, biochemical and serological characterization [Igbinosa and Okoh, 2008], but the process however, is laborious and time consuming [Maheshawi et al., 2011]. Furthermore, effective characterization and differentiation of V. cholerae from certain members of Vibrio species such as V. mimicus or Aeromonas species with respect to their biochemical properties is quite difficult [Maheshawi et a/., 2011]. This study was therefore aimed at using a combination of biochemical to detect V. cholerae from water samples in Nwangele local government area of Imo state.

1.2  Statement of Problem

I have come to realize that in Nwagele local government; there have been a case of dysentery as a result of consumption of contaminated water from their river source, which prompted this research to isolate and characterize the causative organism (V. cholerae) from water sample in the Nwangele local government area of Imo State.

1.3  Aims and Objectives

The research is carried out with the outmost aim of determining the increase in the desease rate of cholera in Nwangele local government area of Imo state which involves the isolation and characterization of vibro cholerae from water samples in the area. The knowledge of this will help in the control of Vibrio – associated gastroenteritis in Nigeria as the awareness of the dangers associated with the consumption of raw or unboiled water from the river in Nwangele will be created to the masses.

Pages:  42

Category: Project

Format:  Word & PDF        

Chapters: 1-5                                 

Material contains Table of Content, Abstract and References.