KNOWLEDGE, ATTITUDE AND PERCEPTION OF LASSA FEVER AMONG PEOPLE ATTENDING PRIMARY HEALTH CARE (PHC) IN OSUN STATE, SOUTHWESTERN NIGERIA

CHAPTER ONE

INTRODUCTION

1.1 Background of Study

Lassa fever (LF) is an acute viral haemorrhagic illness caused by the Lassa virus (LASV), an enveloped single-stranded RNA virus belonging to the family Arenaviridae. The disease was first identified in 1969 in the town of Lassa, Borno State, Nigeria, and has since become endemic across West Africa (Naeem et al., 2023). It is one of the diseases designated for mandatory weekly epidemiological reporting to the Nigerian health authorities, reflecting the persistent public health burden it poses at the national level (Nigeria Centre for Disease Control [NCDC], 2023).

Lassa fever is responsible for significant morbidity and mortality in Nigeria and other West African nations. Annual outbreaks have been documented with increasing frequency, and Nigeria has consistently borne the highest burden in the sub-region (Al-Mustapha et al., 2024). Between 2020 and 2023, a total of 28,780 suspected cases and 4,036 laboratory-confirmed cases were recorded from 34 of Nigeria’s 37 states, resulting in 762 deaths and an overall case fatality rate (CFR) of 18.9% (Al-Mustapha et al., 2024). The 2022 outbreak alone resulted in 1,067 confirmed cases and 189 deaths across 27 states, with the Ondo, Edo, and Bauchi states accounting for 72% of annual cases (Naeem et al., 2023). By 2024, confirmed cases had risen to 1,309, with an epidemiological trend showing a clear and alarming trajectory of increase from 25 confirmed cases in 2015 (Abubakar et al., 2025).

The causative agent, LASV, is an enveloped, ambisense, bi-segmented RNA virus with a high degree of genetic variability stemming from transcription errors, with up to 32% nucleotide diversity identified across seven circulating lineages (Garry, 2023; Lassa Fever: Critical Review, 2024). The principal natural reservoir host is Mastomys natalensis (the natal multimammate rat), a rodent species that is ubiquitous and widely distributed across sub-Saharan Africa (Mariën et al., 2024). These peridomestic rodents do not develop illness from the infection and shed the virus persistently through urine, saliva, faeces, and other body fluids, facilitating zoonotic transmission to humans primarily via direct contact or ingestion of contaminated food and water (Happi et al., 2024).

The pathogenesis of Lassa fever is characterised by impaired cellular immunity and immune suppression. Severe cases present with profound immunosuppression, dysregulation of pro-inflammatory cytokines, and systemic viraemia affecting multiple organ systems (Differential Immune Responses, 2019; Pathogenesis of Lassa Fever, 2012). Clinical manifestations range from mild flu-like symptoms including fever, myalgia, sore throat, nausea, vomiting, and abdominal pain to severe complications such as haemorrhage, encephalitis, hearing loss, and multi-organ dysfunction (Garry, 2023; Lassa Fever: Comprehensive Review, 2025). A critical diagnostic challenge is the overlap of early LF symptoms with those of malaria and other febrile illnesses, making timely case detection particularly difficult in endemic settings (Frontiers in Epidemiology, 2026).

Lassa fever transmission occurs through two primary routes: zoonotic (rodent-to-human) and human-to-human contact. The latter is especially pertinent in healthcare settings, where nosocomial outbreaks have been well documented due to inadequate infection prevention and control (IPC) measures (Happi et al., 2024). In Nigeria, healthcare workers (HCWs) continue to account for a significant proportion of Lassa fever infections and fatalities during outbreak seasons. A 2025 analysis of HCW infections in 2023 and 2024 found that 51% did not use appropriate personal protective equipment (PPE), and 53.3% had received no IPC training (Gadanya et al., 2025). The seasonal peaking of Lassa fever cases between November and April during the dry season when rodent-human interactions intensify due to food scarcity further underlines the importance of year-round preparedness at all levels of the health system, including at primary health care (PHC) facilities (Resurgence of Lassa Fever, 2025).

Contributing factors to the persistent burden of Lassa fever in Nigeria include poor sanitation, overcrowding, inadequate resources for case management, weak epidemic preparedness, and limited public health literacy (Resurgence of Lassa Fever, 2025). These are compounded by underlying structural weaknesses in Nigeria’s health system, including a critically insufficient health workforce of only 1.83 skilled workers per 1,000 people far below the WHO’s recommended ratio of 4.5 (Gadanya et al., 2025; NCDC, 2023). Climate change and urbanisation are also projected to exacerbate outbreak frequency by altering rodent population dynamics and expanding the geographical range of Mastomys natalensis (Klitting et al., 2022).

Osun State, located in South-western Nigeria, shares geographical proximity with Edo and Ondo States, which have consistently recorded the highest burden of confirmed Lassa fever cases in Nigeria (NCDC, 2023). Studies conducted in Osun State, including in the Iwo and Oluponna communities, have revealed low levels of community knowledge about Lassa fever, with only 15.4% of residents demonstrating good knowledge of the disease despite 79.11% having heard of it (Aromolaran, Samson, and Falodun, 2023). These findings underscore the critical need for community-level and health facility-based interventions in the state.

Primary health care (PHC) facilities serve as the first point of contact between the community and the formal health system. Personnel at PHC facilities are often the first healthcare workers to encounter suspected Lassa fever cases, placing them at elevated occupational risk while also making them critical gatekeepers for early case detection and referral. Where knowledge, attitude, and preparedness at the PHC level are inadequate, the likelihood of missed diagnoses, delayed management, and nosocomial spread increases substantially. This reality underscores the urgent need to systematically assess the KAP of individuals attending PHC centres in Lassa fever-endemic states such as Osun to guide targeted intervention strategies.

1.2 Statement of the Problem

Despite decades of documented Lassa fever outbreaks in Nigeria, knowledge of the disease among the general population and even among healthcare workers remains suboptimal. Studies conducted at the PHC and community levels have consistently demonstrated knowledge gaps, negative attitudes, and poor preventive practices. In a community study conducted in Ile-Ife, Osun State, approximately 76% of respondents had inadequate knowledge of Lassa fever, 54% displayed negative attitudes, and 51% engaged in poor preventive practices (Olowookere et al., 2017, cited in Aromolaran et al., 2023). Similarly, a 2023 survey of residents in Iwo and Oluponna areas in Osun State found that while the majority had heard of Lassa fever, only 15.4% had good knowledge about the disease (Aromolaran, Samson, and Falodun, 2023).

At the healthcare worker level, studies have similarly reported concerning deficits. A multi-centre cross-sectional assessment of healthcare workers in Northern Nigeria during an outbreak found that knowledge of Lassa fever, its prevention, and control practices varied widely and was significantly associated with having received prior Lassa fever training (Wada et al., 2022). A 2023 study in Ondo State revealed that although 67.8% of HCWs demonstrated good knowledge of Lassa fever, over 40% had not reported a confirmed case in the preceding year, suggesting knowledge alone does not translate into action (Assessment of Lassa fever Reporting, 2025).

In terms of IPC practices, a significant proportion of healthcare workers across Nigeria have been found to inconsistently apply standard and transmission-based precautions. Data from 2023 and 2024 HCW infection investigations revealed that 51% of infected HCWs did not use appropriate PPE and 53.3% had never received IPC training on Lassa fever (Gadanya et al., 2025). These systemic gaps in knowledge, attitudes, and IPC practice at all levels of the health system, from tertiary facilities to PHCs, continue to fuel nosocomial transmission and occupational risk.

Most previous studies in Nigeria have focused on secondary and tertiary healthcare facilities or on specific outbreak contexts, leaving a critical evidence gap regarding the KAP of people attending PHC facilities in non-outbreak settings. Understanding how PHC attendees in Osun State perceive and respond to Lassa fever is vital for the design of effective, context-sensitive public health interventions. This study, therefore, sought to fill this gap by systematically assessing knowledge, attitude, and perception of Lassa fever among people attending PHC facilities in Osun State.

1.3 Purpose of the Study

The general objective of this research is to assess the knowledge, attitude, and perception of Lassa fever among people attending primary health care in Osun State, South-western Nigeria. The specific objectives are as follows:

1. To assess the level of knowledge of Lassa fever among people attending PHC facilities in Osun State.

2. To assess the attitude and perception of Lassa fever among people attending PHC facilities in Osun State.

3. To determine the association between knowledge, attitude, and perception of Lassa fever and the socio-demographic characteristics of respondents.

4. To identify the perceived causes, symptoms, and consequences of Lassa fever among PHC attendees in Osun State.

5. To identify barriers to preventive practices and care-seeking behaviour among PHC attendees with respect to Lassa fever.

1.4 Research Questions

The following research questions were formulated based on the objectives of this study:

1. What is the level of knowledge of Lassa fever among people attending PHC facilities in Osun State?

2. What are the attitudes and perceptions of Lassa fever among people attending PHC facilities in Osun State?

3. Is there a significant association between knowledge, attitude, and perception of Lassa fever and the socio-demographic characteristics of respondents?

4. What are the perceived causes, symptoms, and consequences of Lassa fever among PHC attendees in Osun State?

5. What are the barriers to adopting preventive practices and care-seeking behaviour regarding Lassa fever among PHC attendees?

1.5 Scope of Study

This research project is geographically delimited to Osun State in South-western Nigeria. The study population comprises individuals attending primary health care facilities within the state. The study focuses exclusively on assessing knowledge, attitude, and perception of Lassa fever and does not extend to clinical management of cases or laboratory diagnosis. The study design is cross-sectional and quantitative in nature, aimed at capturing the current state of KAP among PHC attendees at a specific point in time.

Osun State is geographically proximate to Edo and Ondo States, which have consistently reported the highest Lassa fever burden in Nigeria (NCDC, 2023). Although Osun State is not among the highest-burden states, its proximity to endemic hotspots and the documented low community-level knowledge of Lassa fever within the state (Aromolaran et al., 2023) make it a relevant and justifiable study setting for this investigation.

1.6 Significance of Study

The findings of this study have substantial practical and academic significance. At the policy level, the study is expected to provide evidence-based data that can inform the design of context-specific Lassa fever communication campaigns and health education programmes targeting PHC attendees and workers in Osun State and similar settings across South-western Nigeria. This is particularly important given that current evidence shows a disconnect between disease awareness and preventive behaviour in communities within and around endemic zones (Aromolaran et al., 2023).

At the health systems level, the study generates data that can guide the strengthening of PHC capacity for Lassa fever surveillance, early detection, and response. Given that PHC workers infected with Lassa fever constitute approximately 15% of HCW cases in Nigeria (Gadanya et al., 2025), improving their knowledge and IPC practices through targeted training and resource allocation can significantly reduce occupational transmission and protect the frontline health workforce.

For academic and research communities, this study contributes a body of evidence on KAP related to Lassa fever at the PHC level in South-western Nigeria, a relatively understudied dimension. It will serve as a reference for future researchers and policymakers, particularly as the geography of Lassa fever outbreaks continues to expand. Furthermore, the study methodology and findings may be adapted for similar KAP assessments in neighbouring states and countries as part of regional disease control strategies.

1.7 Operational Definition of Terms

Lassa Fever: An acute viral haemorrhagic illness caused by the Lassa virus, an RNA virus of the Arenaviridae family. The disease is primarily transmitted to humans through contact with food or household items contaminated by infected Mastomys natalensis rats, and can also be spread from person to person through contact with infected bodily fluids. It is endemic in West Africa and is characterised by fever, general malaise, and in severe cases, haemorrhage and multi-organ failure.

Knowledge: In the context of this study, knowledge refers to the level of awareness and factual understanding that PHC attendees have about Lassa fever, including its causative agent, mode of transmission, clinical features, prevention strategies, and treatment options.

Attitude: Refers to the respondents’ evaluative dispositions, feelings, or predispositions whether positive, negative, or neutral towards Lassa fever, its prevention, and care-seeking behaviour.

Perception: The subjective interpretation and understanding of Lassa fever held by respondents, including their risk perception, beliefs about susceptibility, severity, and the effectiveness of preventive measures.

Primary Health Care (PHC): The first level of contact between individuals, the family, and the community with the national health system. In Nigeria, PHC facilities provide basic preventive, promotive, curative, and rehabilitative services closest to the communities they serve.

Nosocomial Infection: A hospital-acquired infection contracted by a patient or healthcare worker during the process of receiving or providing care in a health facility. In the context of Lassa fever, nosocomial transmission refers to spread occurring within healthcare settings due to inadequate infection prevention and control measures.

Zoonotic Transmission: The transfer of an infectious disease from animals to humans. In Lassa fever, zoonotic transmission involves human exposure to Mastomys natalensis rodents or their excreta.

1.8 Limitations of Study

This research project encountered certain limitations that are acknowledged herein. First, financial and time constraints restricted the scope of data collection, which may affect the generalisability of the findings beyond the sampled PHC facilities. Second, the cross-sectional design of the study limits the ability to draw causal inferences, as data were collected at a single point in time.

Third, social desirability bias is a potential limitation inherent in self-report questionnaire studies. Respondents may have provided answers they perceived as socially acceptable rather than truthful responses, particularly on sensitive topics such as hygiene and preventive practices. Fourth, some respondents did not return their questionnaires or completed them incompletely, reducing the effective sample size. Only correctly completed and returned questionnaires were included in the analysis.

Fifth, literacy levels of some respondents required the interviewer-administered approach, which may have introduced interviewer bias. Despite these limitations, necessary measures were taken to minimise their impact, and the findings of this study are considered sufficiently valid to contribute meaningfully to the literature on Lassa fever KAP in South-western Nigeria.

1.9 Organisation of the Study

This research is organised into five chapters. Chapter One provides the background of the study, statement of the problem, research objectives, research questions, scope, significance, operational definitions of terms, limitations, and organisation of the study. Chapter Two presents a comprehensive review of relevant literature on Lassa fever, including its epidemiology, virology, clinical features, transmission dynamics, and previous studies on knowledge, attitude, and perception of Lassa fever in Nigeria and other endemic settings.

Chapter Three details the research methodology, including the study design, study area, study population, sampling technique, data collection instruments, and data analysis methods. Chapter Four presents the results of the study, including descriptive statistics and inferential analysis of the data collected. Chapter Five provides the discussion of findings, conclusion, and recommendations based on the results of the study.

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