Medical Microbiology

RNAviruses 443

Flavivirus(ArthropodborneYellowFeverType)

Pathogen.Theflavivirusfamilyincludes 63 species,amongthemtheproto-

typicvirusofthefamily,theyellowfevervirus,andthepathogenthatcauses

European tickborne encephalitis (spring-summer meningoencephalitis,

SSME).Table8. 3 liststheflavivirusesthatcausesignificanttravelers’diseases.

Pathogenesisandclinicalpicture.Thearthropodborneflavivirusescause

diseasesofdifferentlevelsofseverity.Theinfectionsaretypicallybiphasic

withaninitial,notverycharacteristicphaseincludingfever,headache,mus-

clepain,andinsomecasesexanthem(Denguelikedisease).Thisphasein-

Table8. 3 OverviewoftheMostImportantFlaviviruses(arthropodborne)

Viralspecies Transmitting

vector

Geographic

spread

Syndrome

Dengue Mosquito

(Aedes,Stegomyia)

WestAfrica,

Pacific,Southand

SoutheastAsia,

Caribbean,

Venezuela,

Colombia,Brazil

Denguesyndrome,

DHF,DSS

Yellowfever Mosquito(Aedes) WestandCentral

Africa,Southand

CentralAmerica

Hemorrhagicfever

Japanese

Bencephalitis

Mosquito(Culex) East,Southeast

andSouthAsia,

westernPacific

Encephalitis

St.Louis

encephalitis

Mosquito(Culex) NorthandCentral

America,Brazil,

andArgentina

Encephalitis

WestNilefever Mosquito(Culex),

ticks(Argasidae)

EastandWest

Africa,Southand

SoutheastAsia,

Mediterranean

countries,recently

USAaswell

Denguesyndrome,

encephalitis

Tickborne

encephalitis

(CentralEuropean*

andRussian)

Ticks(Ixodes) CentralEurope,

Russia

Encephalitis

* Syn.spring-summermeningoencephalitis(SSME)

8

Kayser, Medical Microbiology © 2005 Thieme