Dengue hemorrhagic fever is a severe, often fatal, complication of Dengue fever.
Serious life-threatening condition.
Frequently children and others are affected whom previously infected with one serotype or strain of dengue virus and subsequently become reinfected with a different serotype or strain.
The secondary immune response leads to the formation of virus-antibody immune complexes which activate complement.
These complements are causing vascular damage and dissaminated intravascular coagulation (DIC) with spontaneous bleeding.
In some patients, DHF progresses to circulatory collapse, referred as dengue shock syndrome (DSS).
Dengue fever is found mostly during and shortly after the rainy season in tropical and sub tropical areas of
South East Asia and China
Caribbean and Central and South America
Australia and the South and Central Pacific
GROUP : IV
Specie :Dengue Virus
Dengue is a four types.
DEN-1, DEN-2, DEN-3, DEN-4, cause dengue (DEN) and dengue hemorrhagic fever (DHF).
These viruses are transmitted by the bite of Aedes mosquitoes.
Replication and transmission
Virus transmitted to human by mosquito bite.
Virus replicate in target organs.
Virus infects white blood cells and lymphatic tissues.
Virus released and circulates in blood.
Two main species of mosquito. Aedes aegypti Aedes albopictus
Dengue is not contagious from person to person.
Aedes mosquitoes usually bites during day time.
Dengue usually start with fever within 4-7 days after been bitten by an infected mosquitoes.
Pain in eyes
Severe joint and muscle pain
Nausea and vomiting
Enlarged lymph glands
> Abdominal pain
> Hemorrhagic symptoms
Virus enter into the blood circulation by multiplication of virus in the reticuloendothelial system.
Leucopenia is the most infectious cause.
The diagnosis of dengue is usually made clinically.
The classis picture is high fever with no localizing source of infection.
A petechial rash with thrombocytopenia and relative leucopenia.
Low platelet and white blood cell count
Blood test showing blood containing antibodies to the virus.
Dengue test performed by the immunochromatographic method using the BIAS-3 (bi-directional immuno assay system) dengue IgG/IgM kit.
BIAS-3; two step assay for the differential detection of IgG or IgM antibodies to dengue virus in serum or whole blood.
This test is the membrane based screening test to differentially detect the presence of antibodies to dengue virus.
Lateral flow immunochromatographic type assay.
Once the sample is added to the sample pad along with diluents the mixture passes bi-directionally through two antibody binding complexes which then binds the 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.
Negative Only one pink/purple band appears in the Control areas of the BIAS test device
Positive One or Two pink/purple bands appear in the Test area of the BIAS test device and one line each in the Control area of the test device
SECONDARY DENGUE INFECTION
IgG and IgM Positive PRIMARY DENGUE INFECTION
There is no specific treatment for classic dengue fever, and most people recover within two weeks
To help with recovery health care experts recommend