CHPTER ONE

INTRODUCTION

1.1 Background of The Study

Helicobacter pylori (H. pylori) is a motile, Gram‑negative, microaerophilic bacillus that parasitizes the gastric mucous layer and the epithelial lining of the stomach causing duodenal ulcers, gastric ulcers, mucosa-associated lymphoid tissue lymphoma (MALT) and cardiovascular disease amongst others (Gunaletchumy et al., 2014; Yu et al., 2017). “Helico” in the word “Helicobacter” means spiral, which indicates that the bacterium is spiral in shape.

Helicobacter pylori infection remains one of the most common chronic bacterial infections affecting humans. Pregnant women and children are among the most vulnerable groups to H. pylori infection. In pregnant women, the H. pylori infection is associated with nausea, vomiting, anemia, fetal growth restriction, fetal anomalies and low birth weight of infants (Azami et al., 2017). Treatment failure of H. pylori infection has been linked to bacterial resistance and poor patient compliance (Yang et al., 2014).

The routes of transmission of H. pylori have not been clearly identified. However, H. pylori can be transmitted via fecal-oral or oral-oral route, depending on lifestyle/environment factors such as hygiene, water supply, and living conditions (Goh et al., 2011; Abebaw et al., 2014).

Factors that have been associated with the acquisition of H. pylori infection include; high density crowding, poor sanitary practices, family income, educational level, age, occupation, religion and poor water supply (Yakoob et al., 2017). Furthermore, Houseflies have been shown to have the potential to transmit the organism mechanically implying poor sanitation is a risk factor for its spread (Perry et al., 2006).

Globally, the fourth most common cancer is gastric cancer caused by Helicobacter pylori and it is the second cause of mortality due to cancer in the world (Atherton and Blaser, 2009).

7. pylori infection affects more than half of the adult population worldwide, but the prevalence of H pylori infection varies widely by geographic area, age, race, and socioeconomic status (Yakoob et al., 2017). In developing countries, 70%–90% of the population harbor H. pylori which is mostly acquired during childhood, while in the developed countries, the prevalence is lower ranging from 30% to 40% (Saad and Chey, 2008). Various studies have reported the prevalence of H. pylori during pregnancy ranging from 7.6% to 94% whereby 7.5% to 42.9% have being reported in European countries, 24% – 61% noted in Asian countries, 50% – 70% registered in the American countries and more than 52% in Africa (Abbasalizadeh et al., 2016).

There is a paucity of information on the prevalence of H. pylori and associated risk factors in Cameroon. Previous studies in Cameroon reported H. pylori prevalence of 72% (67/93) from biopsies samples with evidence of gastritis and 92.2% from gastric biopsies of patients with gastroduodenal pathologies (Ndip et al., 2008). A previous study carried out in Buea and Limbe health districts of Southwest Cameroon showed that the prevalence of H. pylori is 52.27% (Ndip et al., 2004). Also, a recent study performed by Agbor et al. (2018) in Melong Health District in West Cameroon revealed that, the seroprevalence of H. pylori infection is 43.4%.

The diagnostic techniques utilized to detect H. pylori infection are grouped as invasive and noninvasive tests (Gold et al., 2014). Noninvasive methods consist of the stool antigen test, urea breath test (UBT), and blood test for detection of H. pylori antigens or anti- H. pylori antibody while the invasive tests involves histology, endoscopy, rapid urease test, molecular methods (PCR) and culture (Wang et al., 2015).

1.2 Statement of The Problem

Helicobacter pylori infection remains one of the most common chronic bacterial infections affecting humans particularly in pregnant women and teenagers. It is designated as a Class 1 carcinogen by the World Health Organization because it is the etiologic factor in the development of gastric cancer and it is considered the second cause of mortality due to cancer in the world (Atherton and Blaser, 2009; Alvarado‑Esquivel, 2013). Generally, Helicobacter pylori is responsible for duodenal ulcers, gastric ulcers, mucosa-associated lymphoid tissue lymphoma (MALT), diabetes mellitus and cardiovascular disease amongst others (Gunaletchumy et al., 2014; Yu et al., 2017). Pregnant women and children are among the most vulnerable groups to H. pylori infection. In pregnant women, H. pylori causes nausea, vomiting, anemia, fetal growth restriction, fetal anomalies and low birth weight of infants (Azami et al., 2017). Overall, there is a paucity of information on the prevalence and associated risk factors of H. pylori among pregnant women and children in the South West Region of Cameroon specifically in Buea Health District.

1.3 Research Questions

1. What is the prevalence of pylori infection in pregnant women and teenagers?
2. What is the prevalence of pylori infection classified according to sex and age?
3. What are the risk factors associated with pylori infection?

1.4 Research Objectives

1.4.1 General Objectives

The main objective is to determine the prevalence and risk factors associated with H. pylori infection among pregnant women and teenagers consulting at the Buea Regional Hospital.

1.4.2 Specific objectives

The specific objectives of this study are to:

• Determine the prevalence of pylori infection among males.
• Establish relationship between pylori infection and sociodemographic factors.
• Determine the risk factors associated with pylori infection in pregnant women and teenagers.
• Compare the prevalence of pylori infection among pregnant and non-pregnant female.
• Determine the prevalence of pylori infection among non-pregnant females

1.5 Rationale of The Study

This study was aimed at determining the prevalence and investigating the risk factors associated with H. pylori infection among pregnant women and teenagers consulting at the Buea Regional Hospital. Generally, there is large gap in knowledge about the prevalence of H. pylori infection among pregnant women and teenagers residing in the Buea Health District. As such, conducting this study is to bridge that gap in knowledge about the prevalence and associated risk factors of the disease. Also, the findings from this study is to enable health planners for better decision making and preventive strategies to manage the disease. Furthermore, understanding the risk factors involved in the acquisition of H. pylori infection among pregnant women and teenagers in Buea Health District is critical for the management and reduction of the prevalence and disease burden in a small scale which can be extrapolated to other communities and hence a larger scale.