1.1 Introduction
Lassa virus (LASV) is a highly prevalent arenavirus that affects two to three million people in West Africa. The majority of human infectious diseases are zoonotic, that is they have a wild or domestic animal origin or reservoir (Han et al., 2015). LF is transmitted to humans when they ingest food contaminated by feces and urine of Mastomys spp. Once humans are infected, transmission also occurs from human to human through contact with contaminated fluid- sputum, seminal fluid, stool, urine and blood, and is spread through aerosol secretions during sneezing (Bonwitt et al., 2017). The World Health Organization listed LF among priority diseases requiring urgent research and development attention (Mehand et al., 2018). An expert system is a computer program designed to solve problems in a domain in which there is human expertise. The knowledge built into the system is usually obtained from experts in the field. Since then, this virus, which causes LF, has been reported in many West African countries (Mylne et al., 2015).
As a prelude to other parts of this study, this chapter will discuss the background upon which this study was initiated, the statement of problems that led to this study, the Aim and Objectives of the study. Others are Significance of the study, Scope of work, Limitations of the Study and Definition of technical terms.
1.2 Background of Study
Lassa fever is found outside West Africa in countries such as Central African Republic and Democratic Republic of the Congo (Richmond et al., 2003). Also, there have been reports of imported Lassa fever to other continents of the world (Kitching et al., 2009; Amorosa et al., 2010; Kofman et al., 2019). The importance of timely diagnosis of Lassa fever is that both the morbidity and mortality associated with Lassa fever can be reduced and also secondary infection from the patient can be prevented. Starting ribavirin early (within the first six days) in addition to supportive care improves clinical outcome in Lassa fever (Richmond et al., 2003).
In developing nations, scarce resources lead to inadequate diagnostic procedures. Malaria can result in anemia (a decreased number of red blood cells). The remains of the destroyed red blood cells clump together and cause blockages in the blood vessels. This can result in brain damage or kidney damage, which is potentially fatal. A particularly serious, potentially life threatening, form of malaria parasite is called Plasmodium falciparum. Similarly, a bacterium called Salmonella typhi (S. typhi) is responsible for typhoid. S. typhi may be spread by consuming contaminated water, beverages and food, after which the bacteria enter the intestines and then the bloodstream, where they may spread to other body parts.
In epidemics and less wealthy countries, after excluding malaria, dysentery or pneumonia, a therapeutic trial time with chloramphenicol is generally undertaken while awaiting the results of Widal test and cultures of the blood and stool (Ryan and Ray, 2004). Apart from malaria and typhoid fever, the rule based expert system designed in this paper is developed to diagnose other types of fever such as pel-ebstein fever, leptospirosis fever, scarlet fever, dengue fever, rheumatic fever, hay fever and lassa fever.
There are many reasons for building an expert system to solve health related problems. Human experts may not always be available or may even be absent from a location. Also, by pooling knowledge of many experts, an expert system may be better than one human expert in its overall performance. An expert system does not get tired and are expected to be more consistent. It can also be used for training and passing on the knowledge derived from the human experts.
Recent studies suggest that outbreaks are largely fueled by independent zoonotic transmission events from infected rodent hosts, whilst approximately 20% of cases result from secondary human to human transmission, typically through super-spreader events in hospital settings (Shehu et al., 2018). In severe cases, death usually occurs within two weeks following onset of symptoms. Epidemiology’s study of Lassa fever in endemic zones is important about the transmission human to human or Mastomys spp. to human and can facilitate decision on control strategies. Although there are extensive studies, a systematic review of different publications on Lassa fever is important. As a whole, this set of studies improves our understanding of the geographical distribution of viral hemorrhagic fever. The study was conducted to investigate the prevalence and dynamism of Lassa fever in West African’s population.
It is against the background that the research decides to embark on this project work with the aim of design a system that will eliminate some of the identified challenges. The new system will provide an online (Internet Based) service for diagnosis would be a contribution to hospital management system by Diagnosing Lassa Fever Diseases. This project is aimed at reducing the drawbacks associated with diagnosing a patient.
1.3 Statement of the Problem
The problems encountered by the existing system include the following:
- People die as a result of wrong self-medication or delayed Lassa fever diseases diagnosis.
- A lot of people that visit the laboratory for diagnosis, experience shortage of finance as a result of wrong diagnosis.
- Some patients complain of not meeting the doctors when they visit the laboratory, hence, their illness becomes critical.
1.4 Aim and Objectives of Study
The main aim of this study is to develop of Expert System for the Diagnosis of Lassa fever Diseases and Ailment. In achieving this aim, the new system will accomplish the following objectives through the design of a system that will;
- Help return the skills of an expert medical doctor in event of eventualities;
- Reduce the risks associated with self-medication, wrong and delayed Lassa fever diseases diagnosis; and
- Reduce the stress and inconveniences experienced by potential patients and not meeting with the doctor on the days of visit.
1.5 Significance of Study
This system when completed and implemented will help allocate the stress of the doctors and other health personnel involved in analysis and prescription of cancer cases as some of the prescription will now be done by the new system when a patient fills in the correct information needed. It also reduces the risk of delayed diagnoses and self-medication which can degenerate the problem. With the growth in information technology, the study offers numerous benefits to the Federal Medical Centre and to any Medical Centre that deals on patient breast and prostate diagnosis.
Besides, the project report will help subsequent researchers who are interested in the topic or related topic as a reference material.
1.6 Scope of the Study
This research work will concentrate on the Design and Implementation of Expert System for Lassa Fever Disease using Federal Medical Center (FMC) Owerri as a case study. The proposed system developed will only cover patient with symptoms for diagnosis and control solutions like drug control and supplement there will be room for diagnosing patient with various kind of symptoms with remedial solution and advice.
1.7 Limitations of the Study
During the course of this study, many things militated against its completion, some of which are:
- Time Constraint: The time frame given to accomplish this project was very short due to school academic calendar and it was carried out under pressure which made the researcher not to implement some necessary features.
- Financial Constraint: There were inadequate finance as a student which affected my research on this study, the problem became more complex coupled with the financial involvement of every research as the available funds from parents were barely enough, which limited the researcher from fully implementing certain aspects of the system.
- Establishment Policies: Establishment policies posed a serious limitation as most staffs are not ready to release information needed for this project work. There were lots of information needed from the staffs of this institution to enhance the study which took them time to release or did not release at all for security purposes, hence some features intended were not added.
1.8 Definition of Terms
Virus: Is a small infectious agent that replicated only inside the living cells of other organisms.
Information System: It is a collection of procedures, people, Instructions and equipment to produce information in a useful form.
Lassa fever: It is an acute viral hemorrhagic disease of 2 to 21 days that happens most frequently in West Africa. The illness was discovered in 1969 when two missionary nurses died in Nigeria (Lecompte et. al., 2006).
