Evaluation of Live Artemisia Annua L. Plants as Mosquito Repellents in Boarding Schools and Households of Mwea Irrigation Scheme, Kirinyaga County, Kenya

Abstract

Mosquitoes have attained public health concern than any other arthropod. The bloodfeeding females transmit the protozoa causing malaria, filarial worms causing elephantiasis, and viral diseases. Malaria is a serious public health issue in sub-Saharan Africa, infecting between 300 and 500 million people annually, and it's the leading cause of infant and child morbidity and mortality. Approximately 70 Anopheles species have been shown to be competent '!;ectors of human malaria. Methods used for malaria control include killing mosquitoes at larval and adult stages and prevention of biting. Mechanical barriers for example, impregnated mosquito bed nets are commonly used to provide protection from mosquito bites. Despite the use of these conventional methods to prevent mosquito bites, there continues to have cases of malarial deaths. The main objective of this study was to evaluate the mosquito repellence effect of live potted Artemisia annua L. plants hung at doors and windows of dormitories in boarding secondary schools of Mwea Rice Irrigation Scheme (MRIS), Kirinyaga County, Kenya. Cross-sectional and experimental ecological study designs were used in this study. Four boarding schools in the MRIS were purposively selected. A total of 340 students were randomly selected from the four schools and a structured questionnaire was administered to the students to gather quantitative data. Also four villages neighbouring the boarding schools were purposively selected and 340 households were systematically sampledfor this study. A structured questionnaire was administered to the 340 selected households to gather both qualitative and quantitative data. Baseline mosquito density measurement was done before introducing Artemisia annua in the schools by collecting mosquitoes in selected dormitories. Potted live A. annua plants were hung at the doors and windows of the selected dormitories. Mosquitoes were collected from the selected dormitories after introducing A. annua using suction tube method. The level of knowledge on mosquito control strategy amongst students was high at 97%. Mosquito control methods at household level were use of mosquito bed net (75.8%), use of firewood and mosquito coil (17%), use of insecticide (24%), and environmental t'management practice (70%).' Mean (± SEM) baseline mosquito density in boarding schools were 47.62±2.20, 48.00 ±1.93 for girls treatment and control dormitories respectively, 38.50±2.82, 42.50±2.01 for boys treatment and control dormitories respectively, and 50.37±2.78, 61.50±3.29 for girls and boys blanks dormitories respectively. Live Artemisia annua introduction resulted in decreases of mean mosquito catches in both the treatments and controls. Differences in the mean mosquito catches in both the control and treatment dormitories were significant at p = 0.001 for the months of March-June respectively. The study concluded that live A. annua reduced the mosquito density in dormitories of boarding schools even when they were separated by 50 metres. The' study recommends that A. annua should be planted near dormitories and other buildings to repel mosquitoes.