Malaria Parasite And It's Effect To Human Health

INTRODUCTION

1.1 Background Of The Study

Malaria has been the focus of multiple declarations, and a range of targets have been set since the beginning of the millennium (WHO, 2015). In Africa`s malaria endemic countries, an average of 30% of all outpatient clinic visits are for malaria (Roll Back Malaria, 2008). In these same countries, between 20% and 50% of all hospital admissions are a consequence of malaria (Roll Back Malaria Partnership, 2013). With high case-fatality rates due to late presentation, inadequate management, and unavailability or stock-outs of effective drugs, malaria is also a major contributor to deaths among hospital inpatients in Africa (Roll Back Malaria Partnership, 2013). People are at increased risk both of becoming infected with malaria and of becoming infected more frequently (Roll Back Malaria Partnership, 2013). Families live in dwellings that offer little protection against mosquitoes and are reluctant towards affording insecticide-treated nets etc (Roll Back Malaria, 2011). 

The population at high risk of malaria incidence in Nigeria is estimated at 135,552,389 (WHO, 2015). The countrys’ confirmed and suspected cases of Malaria incidence as at 2015, stood at 19,555,575 people (WHO, 2015), with adults accounting for over 28% of the victims. Among vector borne diseases, the malaria is influenced by seasonal or spatial changes in the environment (Messina et al., 2011). Environmental factors such as the presence of bushes and stagnant water around homes, rainfall, low altitude and high temperatures favor the breeding of malaria vectors, as well as parasite reproduction within them (Messina et al., 2011). Malaria has, therefore, been defined as an environmental disease (Hay et al., 2000). The key to addressing the challenge of reducing malaria parasite prevalence is an integrated approach that combines preventative measures, such as Insecticide Treated bed Nets (ITNs), Indoor Residual Spraying (IRS), improved access to effective anti-malarial drugs (Kokwaro, 2009), as well as proper environmental management. Climate has been established as an important determinant in the distribution of vectors and pathogens (Odetoyinbo, 1969). Tropical areas including Nigeria have the best combination of adequate rainfall, temperature and humidity allowing for breeding and survival of anopheles mosquitoes (Efe and Ojoh, 2013). An increase in rainfall and temperature enhances mosquito development and improved breeding sites leading to incidence of malaria (Vincent and Sunday, 2015). Rainfall provides the breeding sites for mosquitoes and increases relative humidity necessary for mosquito survival, leading to increase in the number of mosquitoes biting an individual per unit time (Lindsay and Martens, 1998). An adult mosquito`s chance of survivorship is determined by the ambient temperature, humidity and rainfall. Warmer ambient temperatures shorten the duration of the extrinsic cycle, thus increasing the chances of transmission (Jackson and Yang, 2010). Malaria pandemic alone has caught the attention of both the local authorities and international agencies. Several measures have been adopted to reduce the rate of morbidity due to malaria. It is believed that climatic parameters had changed significantly over the past two/three decades (Akinbobola and Oluleye, 2010). Hence, a deeper knowledge of environmental variables, conducive to mosquito vector life cycle, is important to target control interventions most importantly among adults. Modeling environmental variables are very valuable in defining foci of malaria transmission. The development of spatial analytical techniques has created an avenue to evaluate environmental variables that are generated by remote sensing satellite sensors and captured by Geographic Information Systems (GIS) for spatial and temporal environmental analysis (Tanser and Le Sueur, 2002; Thomas et al., 2002). For an effective malaria management especially, the knowledge of adults on how and where climatic and environmental conditions favouring the development and spread of malaria vector can be of great benefit to health management agencies, thus enabling containment and treatment efforts to be focused where most needed. A detailed survey needs to be carried out on the health implications and problems of malaria especially among adults, which is the major interest of this study.

1.2 Statement Of The Problem

Malaria is caused by Plasmodium falciparum, and the mosquitoes Anopheles gambiae, Anopheles funestus, Anopheles arabiensis, and Anopheles moucheti are the major vectors that cause year-round transmission; artemether-lumefantrine (AL) or artesunate + amodiaquine (AS + AQ) is the treatment regime adopted in 2004 [1, 7]. Notably, malaria is one of the most severe global public health problems worldwide, particularly in Africa, where Nigeria has the greatest number of malaria cases.

Major risk factors enhancing malaria prevalence and transmission among adults in Nigeria include demographic factors, environmental factors, and socioeconomic factors. Demographic factors include age and gender, while environmental factors include the presence or absence of bushes and forests which enhance mosquito breeding. Meanwhile, climatic factors include temperature, humidity, and rainfall that may support rapid growth and development of mosquito vectors. Lastly, socioeconomic factors such as education, occupation and income which can directly affect human exposure and treatment pattern. These factors have been well reported, particularly in rural and peri-urban communities in previous studies. Govoetchan and colleagues(Mark 2016), observed that malaria prevalence among adults in Nigeria was 5.5 times higher  compare to young adults (youths). Hence, this study epistle aims at examining the health implications and problems of malaria among adults in Nigeria.