CHAPTER ONE

INTRODUCTION

1.1 Background

Blood transfusion is a mandatory and therapeutic procedure that plays a crucial role in saving patient lives particularly for patients who are undergoing a major surgery, those who had serious injuries who resulted in severe blood loss, those with illnesses that causes anemia like leukemia etc. Globally, it is estimated that 92 million people donate blood annually (Alharazi et al., 2022). About, 1.6million of these blood units are discarded because of the presence of infectious agents (WHO, 2012). Blood transfusion carries the risk of transmitting major infections, such as hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), syphilis, cytomegalovirus (CMV), herpes simplex virus (HSV), and Epstein–Barr virus (EBV), along with toxoplasmosis and malaria (Noubiap et al., 2013). Therefore, collected blood units must be serologically tested to prevent the transmission of infections caused by such pathogens, as per the recommendation of the World Health Organization (WHO) (WHO, 2018).

In 2019, newly infected individuals with chronic hepatitis C and hepatitis B reached over 1.5 million. In addition, 290,000 (230,000–580,000) people died from infections related to hepatitis C in 2019 (WHO, 2021). Additionally, recent data have indicated that hepatitis B and C kill about 1.1 million people and infect another 3.0 million annually (WHO, 2021). Approximately 3.5 million new cases occur annually (Gao et al., 2011), and about 21.3million people are estimated to be carrying the HCV virus in the Eastern Mediterranean region (Fallahian et al., 2011). Recently, the prevalence of hepatitis C infections among blood donors has been 1.0% to 1.6% (Al-Zubiery et al., 2017). HIV is a global health problem with a considerable socioeconomic impact (UNIDOC, 2019). There were almost 1.7 million cases of HIV in 2019, the lowest number since 1990 and down by 23% from the peak in 2010. However, this is still far from the global target of fewer than 500,000 new infections by the year 2020.

 In Cameroon, about 400,000 pints of blood are given each year to meet the need of the approximately 25 million people. The current blood safety guidelines in Cameroon demand that blood banks should routinely perform serological testing for HIV, HBV, HCV, and syphilis. Being a country with one of the highest prevalence of TTIs, there is limited published data from most towns in Cameroon. Previous records indicate that the prevalence of TTIs range from 9.5% to 29.05% with an overall prevalence range of 2.6-3.5% for HIV, 4.8-10.0% for HBV, 1.9-5.7% for HCV and 1.07-3.8% for syphilis (Abongwa et al., 2021). Malaria is endemic in Cameroon with a prevalence rate of 29%. It is the major cause of morbidity and mortality among the most vulnerable groups: children under five (18%), pregnant women (5%), people living with HIV/AIDS (5.5%), and the poor (40%), the last of which constitutes two thirds of the total population estimated at 19 million. In a study carried out in Douala Cameroon, the prevalence of malaria infection among donors was estimated to be 27.54%; with an Overall prevalence of the asymptomatic malaria beeing 10.17% which accounted for 47.36% of all cases of malaria infection (Mogtomo et al., 2016). Transfusion-transmitted malaria (TTM) is a real public health problem. It can impair the health of recipients living in endemic malaria areas and even be fatal despite their relative semi-immunity Children and pregnant women represent the bulk of the recipients of the blood transfusion and therefore are the first-line victims of TTM-related deleterious and lethal effects (Oladeinde et al ., 2014).

1.2 Statement of Problem

Blood transfusion is considered a life-saving procedure but the presence of transfusion transmitted infections (TTIs) is a major public health concern. TTIs such as hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and Treponema pallidum infection (syphilis) are among the greatest threads to blood safety. In Cameroon, the current blood safety guidelines demand blood banks to routinely perform serological testing for HIV, HBV, HCV, and syphilis. Being a country with one of the highest prevalence of TTIs, there is limited published data from most towns in Cameroon. Previous records indicate that the prevalence of TTIs range from 9.5% to 29.05% with an overall prevalence range of 2.6-3.5% for HIV, 4.810.0% for HBV, 1.9-5.7% for HCV, and 1.07-3.8% for syphilis (Abongwa et al., 2021). Like in other endemic countries of Sub Saharan Africa (SSA), the demand for blood transfusion is increasingly important. This increases the risk of TTM in recipients especially children and pregnant women. Unfortunately, the diagnosis of malaria in donors is not done routinely in most countries in SSA and this is often missed (Mogtomo et al., 2016). However, there is little published reports on the trends of TTIs among blood donors in Buea. Despite the fact that these TTIs can cause various complications such Hepatocellular carcinoma for the HBV, AIDS for HIV, severe hemolytic anemia for malaria etc. The purpose of this study, therefore, is to determine the prevalence and trend of HBV, HCV, HIV, syphilis and malaria among blood donors in the Buea regional hospital.

1.4 Rationale of the Study

This study will help the blood donors at the Buea regional hospital blood bank to be aware of the various TTIs and the various routes by which these infections can be transmitted and it will also help us know the prevalence of the various TTIs (HBV, HCV, HIV, Syphilis and Malaria) and give us a better picture of the risks factors associated with their transmission. So as to give a clear picture of the present burden of the disease so that an assessment can be made on how effective the preventive measures have been and how far we still have to go in term of disease prevention and eradication.

 1.5 Research Questions

1. What is the prevalence of TTIs among blood donors at the Buea regional hospital blood bank?
2. What is the prevalence of TTIs with respect to age and gender among blood donors at the Buea regional hospital blood bank?
3. What are the risk factors of malaria among donors attending the Buea regional hospital blood bank?

1.6 Research Objectives

1.6.1 Main Objective

To determine the prevalence of transfusion transmissible infections among blood donors attending the Buea regional hospital blood bank.

1.6.2 Specific Objectives

1. To determine the overall prevalence of TTIs among blood donors attending the Buea regional hospital blood bank.
2. To determine the prevalence of TTIs with respect to age and gender among the blood donors attending the Buea regional hospital blood bank.
3. To determine the risk factors of Malaria among donors at the Buea regional hospital blood bank.