MADE BY

Mehtab shah

B.S MT 3RD YEAR

WHAT IS DENGUE FEVER?

It is an infectious disease It is an infectious disease carried by mosquitoes and carried by mosquitoes and any of four related dengue any of four related dengue viruses.viruses.

The disease is also called The disease is also called

“ “BREAK-BONE” fever.BREAK-BONE” fever.

It some times causes severe It some times causes severe joint and muscle pain that joint and muscle pain that feels like bone are breaking.feels like bone are breaking.

CLASSIFICATION

DENGUE

CLASSIC DENGUE HEMORRHAGIC DENGUE

Dengue hemorrhagic fever Dengue hemorrhagic fever is a severe, often Dengue hemorrhagic fever is a severe, often

fatal, complication of Dengue fever.fatal, complication of Dengue fever.

Serious life-threatening condition.Serious life-threatening condition.

Frequently children and others are affected Frequently children and others are affected whom previously infected with one serotype or whom previously infected with one serotype or strain of dengue virus and subsequently become strain of dengue virus and subsequently become reinfected with a different serotype or strain.reinfected with a different serotype or strain.

The secondary immune response leads to the The secondary immune response leads to the formation of virus-antibody immune complexes formation of virus-antibody immune complexes which activate complement.which activate complement.

CONTD………..

These complements are causing These complements are causing vascular damage and dissaminated vascular damage and dissaminated intravascular coagulation (DIC) with intravascular coagulation (DIC) with spontaneous bleeding.spontaneous bleeding.

In some patients, DHF progresses to In some patients, DHF progresses to circulatory collapse, referred as circulatory collapse, referred as dengue shock syndrome (DSS).dengue shock syndrome (DSS).

EPIDIOMOLOGY

Dengue fever is found mostly during Dengue fever is found mostly during and shortly after the rainy season in and shortly after the rainy season in tropical and sub tropical areas oftropical and sub tropical areas of

AfricaAfrica South East Asia and ChinaSouth East Asia and China IndiaIndia Middle EastMiddle East Caribbean and Central and South Caribbean and Central and South

AmericaAmerica Australia and the South and Central Australia and the South and Central

PacificPacific

VIRUS CLASSIFICATION

GROUP : GROUP : IVIV

FAMILY :FlavivirideaFAMILY :Flaviviridea

Genus :FlavivirusGenus :Flavivirus

Specie :Dengue Virus Specie :Dengue Virus

PATHOGENESITY

Dengue is a four types.Dengue is a four types.

DEN-1, DEN-2, DEN-3, DEN-DEN-1, DEN-2, DEN-3, DEN-4, cause dengue (DEN) and 4, cause dengue (DEN) and dengue hemorrhagic fever dengue hemorrhagic fever (DHF).(DHF).

These viruses are These viruses are transmitted by the bite of transmitted by the bite of Aedes mosquitoes.Aedes mosquitoes.

Replication and transmission

• Virus transmitted to Virus transmitted to human by mosquito human by mosquito bite.bite.

• Virus replicate in Virus replicate in target organs.target organs.

• Virus infects white Virus infects white blood cells and blood cells and lymphatic tissues.lymphatic tissues.

• Virus released and Virus released and circulates in blood.circulates in blood.

CONTD>>>>>>>>

Two main species of mosquito. Two main species of mosquito. Aedes aegypti Aedes aegypti Aedes albopictus Aedes albopictus

Dengue is not contagious from person Dengue is not contagious from person to person.to person.

Aedes mosquitoes usually bites during Aedes mosquitoes usually bites during day time.day time.

SYMPTOMS

Dengue usually Dengue usually start with fever start with fever within 4-7 days within 4-7 days after been bitten after been bitten by an infected by an infected mosquitoes.mosquitoes.

CONTD>>>>>>> High fever High fever

Severe headacheSevere headache

Pain in eyesPain in eyes

Severe joint and Severe joint and muscle painmuscle pain

Nausea and Nausea and vomitingvomiting

Enlarged lymph Enlarged lymph glandsglands

CONTD>>>>>>>>

Some times;Some times;

> Abdominal pain > Abdominal pain

> Vomiting> Vomiting

Occasionally;Occasionally;

> Hemorrhagic symptoms> Hemorrhagic symptoms

CONTD>>>>>>>>>>

Virus enter into the blood Virus enter into the blood circulation by multiplication of circulation by multiplication of virus in the reticuloendothelial virus in the reticuloendothelial system.system.

Leucopenia is the most infectious Leucopenia is the most infectious cause.cause.

Diagnosis

The diagnosis of dengue is usually made The diagnosis of dengue is usually made clinically.clinically.

The classis picture is high fever with no The classis picture is high fever with no localizing source of infection.localizing source of infection.

A petechial rash with thrombocytopenia A petechial rash with thrombocytopenia and relative leucopenia.and relative leucopenia.

Low platelet and white blood cell countLow platelet and white blood cell count Blood test showing blood containing Blood test showing blood containing

antibodies to the virus.antibodies to the virus.

DENGUE TEST Dengue test performed by the Dengue test performed by the

immunochromatographic method using immunochromatographic method using the BIAS-3 (bi-directional immuno assay the BIAS-3 (bi-directional immuno assay system) dengue IgG/IgM kit.system) dengue IgG/IgM kit.

BIAS-3; two step assay for the BIAS-3; two step assay for the differential detection of IgG or IgM differential detection of IgG or IgM antibodies to dengue virus in serum or antibodies to dengue virus in serum or whole blood.whole blood.

TEST PRINCIPLE This test is the membrane based screening This test is the membrane based screening

test to differentially detect the presence of test to differentially detect the presence of antibodies to dengue virus.antibodies to dengue virus.

Lateral flow immunochromatographic type Lateral flow immunochromatographic type assay.assay.

Once the sample is added to the sample pad Once the sample is added to the sample pad along with diluents the mixture passes bi-along with diluents the mixture passes bi-directionally through two antibody binding directionally through two antibody binding complexes which then binds the complexes which then binds the immunoglobulin in the sample.immunoglobulin in the sample.

CONTD>>>>>>> The complex passes over the immobilized antigens on the membrane, if any antibodies to dengue (IgG or IgM) are present the antigens capture them in turn.

This produces a pink/purple band in the test-zone of the device.

The remaining complex continues to migrate to a control area on the test device and produces a pink/purple band each control area.

This control bands indicate that the test has been performed properly.

Interpretation

NegativeOnly one pink/purple band appears in the Only one pink/purple band appears in the Control areas of the Control areas of the BIASBIAS test device test device

CONTD>>>>>>>>

PositiveOne or Two pink/purple bands appear in the Test One or Two pink/purple bands appear in the Test area of the area of the BIASBIAS test device and one line each in test device and one line each in the Control area of the test devicethe Control area of the test device

CONTD>>>>>>>>>>>

SECONDARY DENGUE INFECTIONSECONDARY DENGUE INFECTION IgG PositiveIgG Positive

IgG and IgM Positive IgG and IgM Positive PRIMARY DENGUE INFECTIONPRIMARY DENGUE INFECTION

IgM positiveIgM positive

Treatment

There is no specific treatment for classic There is no specific treatment for classic dengue fever, and most people recover dengue fever, and most people recover within two weekswithin two weeks

To help with recovery health care experts To help with recovery health care experts recommendrecommend

Getting plenty of bed restGetting plenty of bed rest Drinking lots of fluidDrinking lots of fluid Give medicine to reduce feverGive medicine to reduce fever

PreventionPrevention