What is dengue fever, History and control

INTRODUCTION

Dengue fever is an infectious disease transmitted by mosquito and caused by any of the four related dengue viruses. It is also called "break bone fever" because it may cause severe joint and muscle pain. Dengue is transmitted by female Aedes mosquito. Since no vaccine is available, prevention is the best remedy.

HISTORY

Dengue is one of the many viral diseases transmitted by the mosquito. The disease commonly breaks out in explosive epidemics that spread with amazing rapidity as seen in 2011 in Lahore. The disease has affected all warm parts of the world such as Pakistan,  Sri  Lanka,  Bangladesh,  Central Africa,   Central  America and China. It is a disease of monkeys transmitted to them by forest dwelling mosquitoes.

              Outbreaks in human population presumably began when some of these mosquitoes got the virus from monkeys and made way to human villages where they started breeding. Hence infected human beings carried the disease to cities where Aedes took over as the vector.

SYMPTOMS

After an infected mosquito 's bite, incubation period of 4-7 days is required before the symptoms appear in the patient. The symptoms of different types of dengue fever are as follows:

TYPES OF DENGUE FEVER

These includes

Asymptomatic or undifferentiated fever

Dengue fever(DF)

Dengue hemorrhagic fever (DHF)

Dengue shock syndrome (DSS)

DIAGNOSIS

Complete blood count (CBC) showing total number of RBCs, WBCs and platelets per unit volume of blood is the basic diagnostic test.

DENGUE VIRUS

Dengue fever is caused by one of the four types of dengue virus, DEN-1, DEN-2, DEN-3, and DEN-4, Which are called its serotypes.

BIOLOGICAL CONTROL

The use of chemicals nowadays is being discouraged because of its hazards to the environment. The biological control is being favoured because of its harmless nature. Therefore presently the use of natural enemies and predators for the control of this disease is imperative.

Many birds prey on mosquitoes.

Wall lizards (geckos), jumping spiders destroy a number of mosquitoes.

Certain fish are natural predator of mosquito larvae in ponds.

Larvae of other insects also feed on larvae of mosquito.