ehealth digital library

Digital library of
the Tanzania
health
community

An Estimation of the Entomological Inoculation Rate for Ifakara: A Semi-Urban Area in a Region of Intense Malaria Transmission in Tanzania.

Drakeley, C., Schellenberg, D., Kihonda, J., Sousa, C. A., Arez, A. P., Lopes, D., Lines, J., Mshinda, H., Lengeler, C., Armstrong Schellenberg, J., Tanner, M. and Alonso, P. (2003) An Estimation of the Entomological Inoculation Rate for Ifakara: A Semi-Urban Area in a Region of Intense Malaria Transmission in Tanzania. Tropical medicine & international health : TM & IH, 8 (9). pp. 767-774. ISSN 1360-2276

[img]
Preview
PDF
ihi_(26).pdf - Published Version
Available under License Creative Commons Attribution Non-commercial.

Download (335kB)

Abstract

An entomological study on vectors of malaria and their relative contribution to Plasmodium falciparum transmission in the semi-urban area of Ifakara, south-eastern Tanzania, was conducted. A total of 32 houses were randomly sampled from the area and light trap catches (LTC) performed in one room in each house every 2 weeks for 1 year. A total of 147 448 mosquitoes were caught from 789 LTC; 26 134 Anopheles gambiae s.l., 615 A. funestus, 718 other anophelines and 119 981 culicines. More than 60% of the total A. gambiae s.l. were found in five (0.6%) LTCs, with a maximum of 5889 caught in a single trap. Of 505 A. gambiae s.l. speciated by polymerase chain reaction, 91.5% were found to be A. arabiensis. Plasmodium falciparum sporozoite enzyme-linked immunosorbent assay tests were performed on 10 108 anopheles mosquitoes and 39 (0.38%) were positive. Entomological inoculation rate (EIR) estimates were generated using a standard method and an alternative method that allows the calculation of confidence intervals based on a negative binomial distribution of sporozoite positive mosquitoes. Overall EIR estimates were similar; 31 vs. 29 [95% confidence interval (CI): 19, 44] infectious bites per annum, respectively. The EIR ranged from 4 (95% CI: 1, 17) in the cool season to 108 (95% CI: 69, 170) in the wet season and from 54 (95% CI: 30, 97) in the east of the town to 15 (95% CI: 8, 30) in the town centre. These estimates show large variations over short distances in time and space. They are all markedly lower than those reported from nearby rural areas and for other parts of Tanzania.

Item Type: Article
Keywords: Plasmodium falciparum, Tanzania, entomological inoculation rate, transmission intensity,Anopheles arabiensis, A. gambiae
Subjects: Malaria > Vector control
Divisions: Ifakara Health Institute > Impact Evaluation
Depositing User: Mr Joseph Madata
Date Deposited: 24 Oct 2012 11:56
Last Modified: 24 Oct 2012 11:56
URI: http://ihi.eprints.org/id/eprint/771

Actions (login required)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics