Objectives of mosquito density
Answers
Despite centuries of efforts to control mosquitoes as a part of disease
prevention strategies, many regions of the world are still struggling to
overcome the burdens of vector-transmitted diseases. Malaria infects over
300 million people per year, striking disproportionately in areas of poverty
and lower economic growth (Utizinger et al., 2001) and is regarded as one of
the top three causes of communicable illness worldwide. It has been
estimated that, 1 million children in sub-Saharan Africa die each year from
malaria (Tabachnick, 2003). Although recently on the decline, mosquitotransmitted
filariasis has infected over 120 million people globally (Michael
et al., 2006), imparting serious quality of life issues. Dengue virus and the
resulting severe form of dengue hemorrhagic fever, has experienced an
expanding geographic range in recent decades as the Aedes aegypti vector has
returned to regions where it was once eliminated (Elder and BallengerBrowning,
2009). This bears troubling concerns for the management of Aedes
associated infections such as yellow fever as well as for the spread of
chikungunya virus (Nam, 2003). Arboviral encephalitis viruses (including
West Nile, St. Louis encephalitis and Japanese encephalitis) have been found
in North America in the past decade, most notably with the spread of West
Nile through North and Central America (Reiter, 2001).
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Dengue fever is a benign, acute, febrile syndrome occurring in tropical
regions. Dengue has been called the most important mosquito-transmitted
viral disease in terms of morbidity and mortality. Fever, skin rash, bone pain
and nausea and vomiting are common symptoms of this condition. In a small
proportion of cases, the virus causes increased vascular permeability that
leads to a bleeding condition which is similar to disseminated intravascular
coagulation (DIC) and is known as dengue hemorrhagic fever (DHF).
Dengue fever is not contagious through person-to-person contact.
Current the available treatment for the management of dengue fever is
not so far caused effective and some time it seems to be an unfavorable
treatment for the dengue fever due to lack of scientific validation. Marine
halophytes have been used for the treatment of several diseases but,
exploration of this disease for the management of dengue fever has not been
attempted so far. Hence, present study has been undertaken to find out the
most potential marine halophytes for the development of alternative
medicine for the management of dengue fever.
The present study has been undertaken to find out the possibility of
developing mosquito control of insecticides from the marine halophytic
plant parts in the following aspects;
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1. Collection, identification and extraction of bioactive compounds
from mangroves, seaweeds and sea grasses along Gulf of Mannar.
2. Screening of marine plant resources for mosquito larvicidal
activity against dengue fever causing mosquito Ae. aegypti.
3. Screening of column chromatographic fractions of the most
effective marine plant extracts for the mosquito larvicidal activity
against dengue fever causing mosquito Ae. aegypti.
4. Screening of the most effective column chromatographic fractions
to findout the repellent activity against dengue fever causing
mosquito Ae. aegypti
5. Identification of the most effective column chromatographic
fractions of unique chemical classes which showed potential
mosquitocidal activity.