Mmic PBL2 Cheng Hong

Possible Viral Diseases that Might Be Contracted (Part 1)

1. Dengue

-Cause by:
--Dengue virus-Flavivirus family

-Transmission:
--By the bite of the Ades aegypti mosquito
--Bites during the day
--Not transmitted from person to person

-Pathogenesis and symptoms:
--Dengue fever (breakbone fever): Sudden onset of fever, skin rash, muscular pain, recovers in about a week
--Dengue hemorrhagic fever: Acute onset, decrease in platelet count, causing hemorrhage under the skin and GI tract
--Dengue shock syndrome: Severe hypotension(low blood pressure), may cause shock, maybe fatal if not treated immediately

-Suitable precaution:
--Wear mosquito repellent on exposed skin area and wear long pants and long sleeve shirt when possible.



2. Hantavirus Diseases

-Cause by:
--Hantaviruses- Bunyaviruses family

-Transmission:
--The virus is carried by rodents
--Humans infected by direct contact/ aerosols from feces, saliva, urine of infected rodents

-Pathogenesis and symptoms:
--Acute viral disease, the virus damage vascular endothelium thus causing hypotension, hemorrhage and shock
--May also cause impaired renal function

-Suitable precautions:
--Avoid exposure to rodents and their excreta
--Ensure tents are free from rodents and their excreta
--Ensure all food is protected from contamination by rodents



3. Japanese Encephalitis

-Cause by:
--Japanese encephalitis virus- Flavivirus family

-Transmission:
--By the bite from the infected Culex mosquito

-Pathogenesis and symptoms:
--Mild infection: febrile headache, aseptic meningitis
--Severe infection: rapid onset, headache, high fever, meningeal signs (50% is fatal)

-Suitable precautions:
--Vaccination available
--Wear mosquito repellent on exposed skin area and wear long pants and long sleeve shirt when possible.



4. Rabies

-Cause by:
--Rabies virus( rhabdovirus)- Lyssavirus family

-Transmission:
--Bites from infected wild animals (bats, wild boar etc)
--Virus present in the saliva

-Pathogenesis and symptoms:
--Infect human when saliva containing rabies virus from animal bite penetrates into skin
--Headache, fever, malaise, numbness on site of bite, hallucinations, spasms, death must occur if not treated immediately

-Suitable precautions and treatment:
--Vaccination available, post exposure treatment also available
--Avoid contact with wild animals, if bitten, clean wound and wash with disinfectant immediately



5. Yellow Fever

-Cause by:
--Yellow fever virus (arbovirus)- Flavivirus family

-Transmission:
--Bite from infective Aedes aegypti mosquito
--Normally bite during the day

-Pathogenesis and symptoms:
--Acute onset, fever, muscular pain, headache, chills, nausea, vomiting, bradycardia
--May proceed to development of jaundice, abdominal pain, haemorrhage (50% of which will die)

-Suitable precaution:
--Vaccination avalible
--Wear mosquito repellent on exposed skin area and wear long pants and long sleeve shirt when possible.

References :
http://www.who.int/mediacentre/factsheets/fs100/en/print.html
http://www.who.int/biologicals/areas/vaccines/yellow_fever/yellow_fever_background/en/print.html http://www.jungleformula.co.uk/jfrange/index.html


*Note: In yen ting's blog she will cover other Part 2, other possible viral diseases