Abstract
The study set out to determine the presence of mosquito vectors of malaria,
prevalent Plasmodium species as well as some blood parameters related to
malaria pathology in some inhabitants of Aguowa community of Enugu East
Local Government Area of Enugu State, South-Eastern Nigeria. Adult mosquitoes
were sampled indoors using the indoor Pyrethrum Knockdown Collection (PKC)
method. Mosquito breeding sites were sampled for larvae. Venous blood samples
were collected by thumb prick using blood lancet, for the identification of the
various malaria parasites, the haemoglobin level and the Packed Cell Volume. A
total of 273 out of the 945 pupils of the only primary school in the area were
used for the study. The larvae of three species of mosquitoes were identified as
Aedes aegypti (9.3%), Aedes albopictus (13.2%) and Culex quinquefasciatus
(77.5%) Anopheles gambiae (1.1%), Aedes aegypti (4.6%) and Culex
quinquefasciatus (94.5%) were sampled indoors using the Pyrethrum
Kn
1.0 INTRODUCTION
Malaria is an internationally devastating disease and continues to be one
of the most devastating infectious diseases of our time, rivaling Human
Immunodeficiency Virus/ Acquired Immune Deficiency Disease Syndrome
(HIV/AIDS) and Tuberculosis as killer diseases in tropical and subtropical
regions (WHO, 2005) Figure 1. Around 3.2 billion people are at risk of malarial
attack each year, with around 500 million people proceeding to clinical disease
and 2-3 million deaths occurring (Snow et al, 2005). Over 90% of these deaths
occur in sub-Saharan Africa (WHO, 2005). The burden of morbidity and
mortality is biased towards young children, not yet immuned to clinical
symptoms (Snow et al, 2005) and pregnant women, where parasites are
sequestered in the placenta (Rowe and Keys, 2004).
In Africa, Anopheles gambiae and An. melas breeding in sunlit habitats
and An. funestus in shades and An. phorensis in Upper Egypt and Sudan are
responsible for the transmission of malaria parasite. In Nigeria, Anopheles
gambiae complex, An. funestus and An. arabiensis have been incriminated for
malaria transmission with major impact (Oguoma and Ikpeze, 2008) and
Ekanem (1991).
The parasites that cause malarial disease are protozoan organisms that
also infect many animal species including primates, lizards and birds. Four
Plasmodium species are responsible for human malaria: Plasmodium falciparum;
P. vivax, P. ovale, and P. malariae. Plasmodium falciparum is the most virulent
parasite, and is responsible for the majority of malaria – related mortality. It is
found in all malaria endemic regions of the world, and is the most common
human malaria parasite in Africa (WHO, 2005). Plasmodium vivax is rarely
2
found in Africa, but it is the most common species outside Africa (Mendis et al,
2001; Carter and Mendis, 2002).
Anaemia is a fairly common problem encountered in malaria and it poses
special problems in pregnancy and in children. The easiest measures of anaemia
are the haemoglobin and Packed Cell Volume levels. The haematological
parameters of the study community was assessed using haemoglobin and
Packed Cell Volume.
Aguowa community is a slum with about 5000 inhabitants within TransEkulu area of Enugu Metropolis, Enugu-East Local Government Area of SouthEastern Nigeria. It is inhabited by mostly farmers, artisans, students, traders
and civil servants. There are no pipe borne water, health, facilities, schools,
tarred roads, with poor sanitary conditions.
1.1 THE OBJECTIVES OF THE STUDY
The main objective of the study is to sample mosquito vectors of malaria,
determine the prevalent plasmodium species in humans, as well as blood
parameters related to malaria pathology in some inhabitants of Aguowa
community.
1.2 THE SPECIFIC OBJECTIVES
A. Entomological
i) Larval survey of Anopheles mosquitoes.
ii) Indoor survey of adult Anopheles mosquitoes using the Pyrethrum
Knockdown Collection (PKC) method.
iii) Dissection of adult Anopheles mosquitoes collected indoors to
demonstrate the presence of sporozoites in the salivary glands or
gametocytes in the stomach.
3
B. Parasitological
i) To determine the prevalence of infecting Plasmodium species in
the human community, through examination of blood films using
both thick and thin smears
C. Haematology
i) To estimate the Haemoglobin (Hb) level
ii) To determine the packed cell volume (PCV) of the inhabitants of
Aguowa community
1.3 EXPECTATIONS OF THE STUDY
This study, if successfully completed is expected to provide information
and data on:
i) The malaria vectors’ composition in the Aguowa Community
ii) The prevalence of the various species of malaria parasites in some
inhabitants of Aguowa community.
iii) The level of haemoglobin and the packed cell volume in the
inhabitants of the community.