Dengue Virus

By: Inna Gnipp and Hamza Iqbal

Dengue Declassified

   Family: Flaviviridae Genus: Flavivirus Species: Dengue virus

What is the Dengue Virus?

     Arbovirus  Arthropod, Mosquito, born (Aedes aegypti) It is a pathogen that causes   Dengue fever (DF) Dengue hemorrhagic fever (DHF)  Can lead to Dengue shock syndrome (DSS) Has four different serotypes (DEN-1,2,3,4) First reported epidemics in 1780 in Asia, Africa, and North America

Target tissues

 Dengue induces cytokine production in cells           Cytotoxic factor effects endothelial cells involved in most of the following:

Heart Liver

Kidneys Lungs Intestines

Spleen Lymph nodes

Brain

Skin (inflammatory rashes)

Symptoms: DHF

           Fever Headache Muscle and joint pain Dehydration Nausea and/or Haematemesis (vomiting of blood) Epistaxis (Bleeding from the nose, mouth, or gums) Haematuria (Blood in Urine) Pain behind the eyes Plasma leakage Respiratory distress Petechia (Skin rash) and/or Purpura (Lesions)

Diagnostic tests

   Virus isolation by infection of mice using infected mosquitoes  Detection of IgM antibodies in the blood by PCR or Viral isolation (Serology)  ELISA assay) (Enzyme-Linked Immunoabsorbent Thrombopenia Raised hematocrit

Pathogenesis and infection process of Dengue

        Humans are initially infected through a mosquito vector Initial interaction with cell occurs with the viruses ability to infect cell  Primary target, Phagocytes Virus uses cell receptor molecule to enter cell Cell receptor molecules include:  Glycosaminoglycan  Heparan Sulfate (Expressed in almost all cell types) Virus replicates in target organs Infects white blood cells and lymphatic tissues Virus is released and circulates in blood Alternate mosquito then bites host and receives virus

Treatment:

DHF

Prevention:

There is no specific treatment Relieving symptoms and complications:    Plasma volume replacement Sedatives for restless patients Blood transfusion with patients with significant blood loss  Aspirin should be avoided   All efforts of control are aimed against mosquitoes   Elimination of breeding areas Actions to prevent mosquito bites (repellant, nets, and vapors) Vaccinations are pending  Problem is that the vaccination needs to prevent all four serotypes

Epidemiology

 Affects humans  Is prominent in tropical environments  Ideal for Mosquito habitats

What is promoting the disease?

 Global warming is causing climate changes which is causing the disease to move to more environments  (higher altitudes and amplitudes)  More habitats for mosquitoes to thrive in  Spread has been increased by urbanization and population growth  Inability of mosquito control in countries is also a major factor

Morbidity and Mortality

 More than 2.5 Billion people live in areas that have a risk of infection  Over 100 million cases of Dengue infection are reported each year globally  500,000 cases pertain to DHF  DHF has a 5% fatality rate for those infected  People at high risk are children and the elderly

Bibliography

       Chambers, Thomas J., Yan Liang, Deborah A. Droll, Jacob J. Schlesinger, Andrew D. Davidson, Peter J. Wright, and Xiaoshan Jiang. "Yellow Fever Virus/Dengue-2 Virus and Yellow Fever Virus/Dengue-4 Virus Chimeras: Biological Characterization, Immunogenicity, and Protection Against Dengue Encephalitis in the Mouse Model." JVI. 30 Aug. 2002. 06 Dec. 2006 .

Dark, Graham. "On-Line Medical Dictionary." University of Newcastle. 6 Dec. 2006 . Aqeep, A K., A A. Malik, and M S. Elkarsani. "Clinical Presentations and Laboratory Finding in Suspected Cases of Dengue Virus." Saudi medical journal. 27 Nov. 2006. Department of health and human services. 6 Dec. 2006 . Palmer, D R., P Sun, C Celluzzi, J Bisbing, S Pang, W Sun, M A. Marovich, and T Burgess. "Differential effects of dengue virus on infected and bystander dendritic cells." Journal of virology. Feb. 2005. Department of Viral diseases. 6 Dec. 2006 . Reiter, Paul, Sarah Lathrop, Michel Bunning, Brad Biggerstaff, Daniel Singer, Tejpratap Tiwari, Laura Baber, Manuel Amador, Jaime Thirion, Jack Hayes, Calixto Seca, Jorge Mendez, Bernardo Ramierez, Jerome Robinson, Julie Rawlings, Vance Vorndam, Stephen Waterman, Duane Gubler, Gary Clark, and Edward Hayes. "Texas Lifestyle Limits Transmission of Dengue Virus." CDC. Jan. 2003. 6 Dec. 2006 . Thomas, Clayton L., ed. Taber's Cyclopedic Medical Dictionary. 18th ed. Philadelphia: F. a. Davis Company, 1997. 505. Seet, R C., A M. Quek, and E C. Lim. "Symptoms and Risk Factors of Ocular Complications Following Dengue Infection." Journal of clinical virology. 1 Dec. 2006. 10 Dec. 2006 .

Bibliography

         "Dengue: Clinical and Public Health Aspects." CDC. 1 Dec. 2005. Department of Health and Human Services. 10 Dec. 2006 . "Treatment." WHO. 1997. 10 Dec. 2006 . "Dengue/DHF: Fact Sheet on Dengue Fever and Dengue Haemorrhagic Fever." WHO. 4 Aug. 2006. 10 Dec. 2006 .

Cabrera-Hernandez, Arturo, and Duncan R. Smith. "Mammalian Dengue Virus Receptors." WHO. 2005. 10 Dec. 2006 . Simasathien, S, and V Watanaveeradej. "Dengue Vaccine." Journal of the Medical Association of Thailand. Nov. 2005. Pub Med. 11 Dec. 2006 . Schnittler, H J., and H Feldmann. "Viral Hemorrhagic Fever--a Vascular Disease?" Thrombosis and Haemostasis. June 2003. Pub Med. 11 Dec. 2006 . Rigau-Perez, Jose G., Duane J. Gubler, and Gary G. Clark. "Travelers' Health: Yellow Book CH: 4 - Prevention of Specific Infectious Diseases; Dengue Fever." CDC. 2005. 11 Dec. 2006 . Clyde, Karen, Jennifer L. Kyle, and Eva Harris. "Recent Advances in Deciphering Viral and Host Determinants of Dengue Virus Replication and Pathogenesis." JVI. Dec. 2006. ASM Journals. 11 Dec. 2006 .

Anandarao, Ravulapalli, Sathyamangalam Swaminathan, Sirimali Fernando, Asha M. Jana, and Navin Khanna. "Recombinant Multiepitope Protein for Early Detection of Dengue Infections." CVI. Jan. 2006. ASM. 11 Dec. 2006 .