1.0 INTRODUCTION COMPUTER-BASED INFORMATION SYSTEM TO IMPROVE THE DIAGNOSIS OF HIV/AIDS.
Computer-based information system is one of the most exciting uses of the computer; the computer provides a ready store-house of relevant information. Users interact with the system to received professional judgment through the ability of the expert system to carry out complex inferential reasoning.
1.1 HISTORICAL BACKGROUND OF HIV/AIDS
HIV is a lentivirus and like all viruses of this type, it attacks the immune system. Lentiviruses are in turn part of a larger group of viruses known as retroviruses. The name lentivirius” literally means slow virus because they take such a long time to produce any adverse effect in the body. They have been found in a number of different animals including cats, sheep, horses and cattle. However, the most interesting lentivirus in terms of the investigation into the origins of HIV is the simian immunodeficiency virus (SIV) that affects monkeys, which is believed to be at least 32,000 years old.
Below are some of the common theories on how the zoonosis took place.
The hunter theory: SIV was transferred to humans as a result of Chimpanzees being killed and eaten or their blood getting into cuts or wounds on the hunter.
The oral polio vaccine (OPV) theory: the transfer via medical intervention e.g. polio vaccines.
The contaminated needle theory, the use of unsterilized syringes between multiple patients.
The colonialism theory (Heart of Darkness): The harsh rule of the colonial forces on African which led into poor health that weakened their immune system.
AIDS was first described as a disease entity in 1981 in Los Angeles in United States of America. By mid 1982, over 350 people have been diagnosed with AIDS and more than 90% of these people were found to be homosexual. The causative agent, HIV was first identified in 1983. By 1983-1984 case reports appeared from other parts of the world involving hemophiliacs, blood transfusion of clotting factor concentrate, (UNAIDS, 1998).
Acquired immune deficiency syndrome (AIDS) is caused by a virus called human immune deficiency virus (HIV), which killed all or impairs cells of the human immune system and progressively destroys the body’s ability to fight infections and certain cancers. HIV/AIDS is most commonly spread through sexual intercourse with an infected partner.
There are other means of transfer like through blood transfusion sharing of sharp objects like razor blades, clippers etc with infected persons. Research has shown that 80% of HIV transmission is through sexual intercourse and that unscreened blood transfusion accounts for 5% while mother to child transmission for the remaining percentage. Although there are other factors that contributes to the spread of the epidemic, the core causative factors are poverty, a wide range of deep rooted harmful traditional practice (circumcision, polygamy, wife hospitality, wife inheritance (levirate) etc and unintended consequences of rapid modernization and urbanization (including a thriving commercial sex trade, unprotected coercive sex, child labour, overcrowding and forced or voluntary immigration).
The first confirmed AIDS case in Africa was reported in 1984, in Nairobi, Kenya basically through homosexual.
In Nigeria HIV/AIDS infection was first reported by Nasidi and Harry to health officials in 1986.
1.2 STATEMENT OF THE PROBLEM
Since the last few decades, HIV/AIDS has become the greatest epidemic ever in the history of mankind and all indications are that, its threat will continue to increase. It was essential that over 40 million people worldwide, 28.5 million (or 75%) of which resident in Africa are infected with HIV virus. Nigeria accounts for 20% the Africa’s total AIDS figure and 10% of the world’s.
With an official prevalence rate of 3.5 million people living with HIV and AIDS has become a generalized epidemic”. Many people especially those in the poverty stricken countries are ignorant of the disease and thus aid the spread of AIDS and this explains the reason why the epidemic is increasing exponentially in these countries.