Potential role of sylvatic and domestic African mosquito species in dengue emergence.
Dengue virus 2 (DENV-2) strains that circulate in sylvatic habitats of Senegal and other parts of west Africa are believed to represent ancestral forms that evolved into endemic/epidemic strains that now circulate widely in urban areas of the tropics. Previous studies suggested that the evolution of the endemic/epidemic strains was mediated by adaptation to the peridomestic mosquito vectors Aedes aegypti and Ae. albopictus. We conducted experimental infections using sylvatic and peridomestic Senegalese mosquitoes, and both sylvatic and urban DENV-2 strains to determine if endemic DENV-2 adaptation was vector species specific, and to assess ancestral vector susceptibility. Aedes furcifer and Ae. luteocephalus, probable sylvatic vectors, were highly susceptible to both sylvatic and urban DENV-2 strains. In contrast, sylvatic Ae. vittatus and both sylvatic and peridomestic populations of Ae. aegypti were relative refractory to all DENV-2 strains tested. These results indicate that adaptation of DENV-2 to urban vectors did not result in a loss of infectivity for some African sylvatic vectors. Implications for dengue emergence in west Africa are discussed.
Diallo
Mawlouth
M
Institut Pasteur de Dakar, Dakar, Senegal.
Sall
Amadou A
AA
Moncayo
Abelardo C
AC
Ba
Yamar
Y
Fernandez
Zoraida
Z
Ortiz
Diana
D
Coffey
Lark L
LL
Mathiot
Christian
C
Tesh
Robert B
RB
Weaver
Scott C
SC
D000330:Aedes / Q000145:classification / Q000254:growth & development / Q000821:virology*; D000354:Africa, Western / Q000453:epidemiology; D000818:Animals; D002478:Cells, Cultured; D002947:Cities; D003715:Dengue / Q000453:epidemiology* / Q000635:transmission / Q000821:virology; D003716:Dengue Virus / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D004196:Disease Outbreaks; D019353:Endemic Diseases; D019143:Evolution, Molecular; D006801:Humans; D007303:Insect Vectors / Q000145:classification / Q000254:growth & development / Q000821:virology; D013045:Species Specificity; D014197:Trees