FLAVIVIRUS: INTRODUCTION

  • Most flaviviruses are arthropod-borne viruses which cause mild rash and fever or life-threatening hemorrhagic fever and encephalitis in infected individuals. These arboviruses, including dengue, yellow fever, Japanese encephalitis, and tick-borne encephalitis, constitute a major threat to the developing world where ticks and mosquitoes are endemic. Arthropod control and vaccination are essential components of newly developed eradication campaigns.
  • Another member of the flavivirus family is Hepatitis C virus (HCV). Hepatitis C is a non-arthropod-borne virus which was placed in this family due to its physical structure, properties and replication strategy. Hepatitis C was discovered in 1989 after a number of posttransfusion non-A, non-B hepatitis cases were investigated. Hepatitis C is as common in developed nations as Hepatitis A or B. Although 75% of infections are subclinical, chronic disease progresses to cirhosis in 20% of cases. HCV infection may induce the development of hepatocellular carcinoma in rare cases. Most infected individuals contract the disease from unscreened blood transfusions, IV drug use or sexual promiscuity.
  • Hepatitis G virus is also a transfusion associated flavivirus. It was first reported in 1996 and currently very little is known about the virus.