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International Journal of Mosquito Research 2016; 3(4): 31-35
ISSN: 2348-5906
CODEN: IJMRK2
IJMR 2016; 3(4): 31-35
© 2016 IJMR
Received: 06-07-2016
Accepted: 07-08-2016
Celina O Aju-Ameh
Department of Zoology,
University of Jos, Jos,
Plateau State, Nigeria
Samson T Awolola
Department of Molecular
Entomology and Vector Control
Research Laboratory Public
Health Division, Nigeria
Institute of Medical Research,
Lagos, Nigeria
Georgina S Mwansat
Department of Zoology,
University of Jos, Jos,
Plateau State, Nigeria
Hayward B Mafuyai
Department of Zoology,
University of Jos, Jos,
Plateau State, Nigeria
Correspondence
Celina O Aju-Ameh
Department of Zoology, University
of Jos, Jos, Plateau State, Nigeria
Malaria transmission indices of two dominant
anopheles species in selected rural and urban
communities in Benue state North Central,
Nigeria
Celina O Aju-Ameh, Samson T Awolola, Georgina S Mwansat and
Hayward B Mafuyai
Abstract
An entomological survey was piloted to generate baseline entomological data in some communities in
Benue State where such information was not previously available. Indoor resting mosquitoes were
captured using Pyrethrum Spray Catch (PSC) in 2015. Of the 1,734 mosquitoes captured 276 (16%),
were Anopheles species. Molecular assays revealed the presence of Anopheles gambiae sensu. stricto and
Anopheles arabiensis. Human blood meal source was within the range of 97% to 100% clearly
expressing a high degree of human-vector contact. Circumsporozoite (CS) proteins infection status of
engorged female species were determined by Enzyme Linked Immunosorbent Assay (ELISA). The
calculated Sporozoite Infection Rate (SR) for rural was 1.9% and 0% for urban communities
respectively. The Entomological Inoculation Rates (EIR) recorded was 0.4% per person per night
culminating in an annual 146 infective bites per person per year. Our observed data highlights some
malaria risk indices in the study communities.
Keywords: Malaria, transmission indices, vectors, rural, urban, Nigeria
1. Introduction
Malaria is a preventable and curable but life-threatening disease caused by parasites that are
transmitted to people through the bites of infected female Anopheles mosquitoes. These
Anopheles species are widely distributed in Nigeria across all the ecological zones
[1, 3, 4]
Anopheles gambiae and Anopheles arabiensis are the two dominant vectors of human malaria
in sub-Saharan Africa. They occur in sympatry and are of the greatest medical importance as
very efficient malaria vector species
[2, 1, 5]
Four species of the protozoan parasite exclusively
transmitted to man by competent anophelines are Plasmodium falciparum, Plasmodium vivax,
Plasmodium malariae and Plasmodium Ovale, of which Plasmodium falciparum is the most
pathogenic
[6]
. The main activity of these anopheline vectors of malaria that is the basis for this
entomological survey is their blood feeding behaviour. Blood sucking arthropods were
established as agents of human and animal disease in the last quarter of the 19
th
century
[7]
.
Most female Anopheles species feed on warm- blooded animals predominantly mammals;
anthropophagic ones having a preference for man and zoophilic ones preferring other animals.
The blood meal intake and the gonotrophic cycle are intricately related and blood feeding is
the channel for parasite acquisition and transfer of malaria infection,
[8]
. This study presents the
results of a semi-longitudinal entomological survey highlighting some of the malaria risk
indices in the study communities.
According to the latest WHO estimates, released in December 2015,
[9]
there were 214 million
cases of malaria in 2015 and 438 000 deaths. Sub-Saharan Africa continues to carry a
disproportionately high share of the global malaria burden with 88% of malaria cases and 90%
of malaria deaths. It is estimated that 15 countries accounted for 80% of malaria cases and
78% deaths globally. The overall decrease in malaria incidence (32%) between 2000 and 2015
in the 15 countries that accounted for 80% of cases lags behind that in the other countries
(53%).
[9]
The Carter Center in 2012
[10]
reported that approximately 20-30% of all African
malaria cases occur in Nigeria and Ethiopia while the WHO reports that both countries now
account for more than 35% of the global total of estimated malaria deaths
[9]
.