LARVICIDAL ACTIVITY OF EXTRACTS OF CARICA PAPAYA LINN AND DACROYDES EDULIS (G.DON) H.J LAM ON THREE MOSQUITO SPECIES

LARVICIDAL ACTIVITY OF EXTRACTS OF CARICA PAPAYA LINN AND DACROYDES EDULIS (G.DON) H.J LAM ON THREE MOSQUITO SPECIES

CHAPTER ONE

1.0   INTRODUCTION

1.1 Overview

Mosquitoes are an ancient group of insects which have persisted for millions of years. Through the process of evolution, nature has superbly perfected them that they may survive under the most adverse and diverse of environmental conditions (Manimegalai and Sukanaya, 2014). Mosquitoes have been a problem for people all over the world as long as humans have existed. They are the most nuisance creatures of nature and the most medically important arthropod vectors of diseases to humans (Beernste et al., 2000; Arti et al., 2012). They are responsible for the transmission of dengue, malaria, yellow fever, filariasis (Ali et al., 2013), hemorrhagic fever, Japanese encephalitis and other diseases which are today among the greatest health problems in the world. Mosquitoes contribute to social debility and poverty in tropical countries (Rajkumar and Jebanesan, 2005; Alam et al., 2011).

Tropical areas are more susceptible to parasitic diseases and the risk of contracting arthropod borne illnesses is increasing due to climate change and rising temperatures worldwide. Trade and unplanned urbanization have also contributed to the impact of disease transmission in recent years. Mosquitoes have been declared public enemy number one by the World Health Organization and they belong to three genera; (anopheles, culex and aedes) responsible for the transmission of diseases to more than 700 million people annually and are responsible for one (1) death in every seventeen (17) people alive (El-Bahnasawy et al., 2013).

Although an ancient and historical disease, malaria persists in many parts of the world today (Hall and Fauci, 2009). Malaria causes human mortality single-handedly killing nearly 3 million people yearly. Malaria fever is one of the deadliest diseases ravaging Africa (Ubulom et al., 2012). It is estimated to have killed between 537,000 and 907,000 in 2010 alone, 86% being children under the age of five with more than 40% of the world‟s population living in malaria endemic areas (Massebo et al., 2009) and an estimated 3.3 billion people in 109 countries are at risk of contacting this serious and often life threatening disease (Hall and Fauci, 2009; Alam et al., 2010)

LARVICIDAL ACTIVITY OF EXTRACTS OF CARICA PAPAYA LINN AND DACROYDES EDULIS (G.DON) H.J LAM ON THREE MOSQUITO SPECIES