CHAPTER ONE

GENERAL INTRODUCTION

1.1 Background

Chronic hepatitis B virus (HBV) infection is defined by the world health organization (WHO) as having positive hepatitis B surface antigen for at least 6 months (Kamenya et al., 2017). Viral hepatitis is an inflammation of the liver affecting millions of people worldwide every day. HBV is a DNA virus that replicate in the liver cells and causes acute and chronic infections of the liver. It is a major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Most people are unaware of their infection with viral hepatitis and unknowingly transmit the infection to other people, so it is a silent epidemic due to its highly asymptomatic nature (Goa et al., 2017). It is the 10th leading cause of death worldwide. Approximately 686,000 deaths per year are caused by chronic hepatitis and hepatocellular carcinoma (Kamenya et al., 2017). HBV affects 240 million people globally, with the highest prevalence in East Asia and Sub-Saharan Africa (SSA). Cameroon is also in an endemic area for HBV where HBV infection in the general population accounts for 12%, with high prevalence in the younger population (Noah et al., 2011). World health organization (WHO) estimates that in 2015, 257 million people were living with chronic hepatitis b infection (defined as hepatitis b surface antigen positive). In 2015, hepatitis b resulted in an estimated 887,000 deaths mostly from cirrhosis and hepatocellular carcinoma (i.e primary liver cancer).

Hepatitis b virus was discovered in 1965 by Dr. Baruch Blumberg who won the Nobel Prize for his discovery. Originally the virus was called the “Australia antigen” because it was named for an Australian aborigine’s blood sample that reacted with an antibody in the serum of an American hemophilia patient (hepb.org). As of 2016, 27 million people (10.5% of all people estimated to be living with hepatitis b) were aware of their infection, while 4.5 million (16.7%) of the people diagnosed were on treatment.

HBV is reported to be 50–100 times more infectious than HIV; it can survive for several weeks even in dried blood. Blood is the most important vehicle for its transmission. Semen, tears, and saliva are also possible vehicles for its transmission. Percutaneous contact with infected blood, unprotected sexual contact, infected mother-to-infant, unsafe blood transfusion, sharing razors, toothbrushes, needles, and syringes, tattooing, and body piercing are some modes of HBV transmission (Goa et al., 2019). A number of blood tests are available to diagnose and monitor people with hepatitis B, they can be used to distinguish acute and chronic infection; Laboratory diagnosis of hepatitis B infection focuses on the detection of the hepatitis B surface antigen HBsAg,

Previous studies in sub-Sahara Africa shows that infection by HBV affect between 5% and 10% of the Population that vary from region to region: a study by Jean Joel et al. in 2017 reported a prevalence of 11.2% in Cameroon with a prevalence of 9.7% among pregnant women in South west region (Nde et al., 2014). And 12.6% in the north-west region of Cameroon (Zoufaly et al., 2012).  The prevalence keeps increasing as a result of mother to child transmission perennially, blood transfusion, sexual promiscuity and mucosa contacts with bodily fluids. The incidence can be reduced by determining the prevalence and using the information to sensitize the population and encouraged screening and vaccination against hepatitis B virus.       

1.2 Statement of the problem

The prevalence of hepatitis B virus infection is on the increase worldwide as reported by world health organization, 2000 million people are infected by hepatitis B virus globally. Meanwhile in Cameroon, the prevalence of hepatitis B virus among pregnant women is 9.7%. Following the world health organization, hepatitis B virus ought to be completely eradicated by the year 2002 that is twenty years after the discovery of the vaccine by 1982. Also, counting on the effectiveness of the vaccine which stands at 95%, prevalence of hepatitis B virus to be at its base now. This increase in prevalence lead to many deaths from hepatitis B virus infection worldwide as 780000 people died yearly from hepatitis B virus infections globally with 25% of this from Africa and Cameroon being in Africa is of the same the trench. Due to scarcity of data on HBV among individuals in the South west region, it is imperative to carry out this study to determine the burden of HBV and to assess the knowledge of the infection among individuals in Buea.

1.3 Research questions

1. What is the prevalence of HBV infection among patients attending Saint Veronica Medical Centre?
2. Do patients attending Saint Veronica Medical Centre have adequate knowledge on HBV infection?
3. What are the factors that predisposes patients attending Saint Veronica Medical Centre to HBV infection?

1.4 Research objectives

1.4.1 Main objectives

To determine the prevalence and factors associated with hepatitis B virus infection among individuals attending Saint Veronica Medical Centre Buea, south west Cameroon.

1.4.2 Specific objective

• To determine the prevalence of hepatitis B virus, among Individuals attending Saint Veronica Medical Centre Buea, south west Cameroon.
• To assess the knowledge of patients attending Saint Veronica Medical Centre on HBV.
• To identify the factors that predisposes patients attending Saint Veronica Medical Centre to HBV infection.

1.5 Rationale of the study

Knowing the magnitude of HBV infection and associated risk factors for its transmission is fundamental data for health planners and health professionals for appropriate medical management and monitoring in Cameroon public health. Moreover, this can also help to undertake effective prevention of liver related complications once the status of HBV infection is recognized.