Chikungunya virus and Aedes mosquitoes: saliva is infectious as soon as two days after oral infection

PLoS One. 2009 Jun 12;4(6):e5895. doi: 10.1371/journal.pone.0005895.


Background: Aedes aegypti and Aedes albopictus are potential vectors of chikungunya virus (CHIKV). The recent CHIKV outbreaks were caused by a new variant characterized by a mutation in the E1 glycoprotein gene (E1-226V) which has favored a better transmissibility by Ae. albopictus. As Ae. albopictus tends to replace Ae. aegypti in many regions, one question remained: is Ae. albopictus as efficient as Ae. aegypti to transmit the variant E1-226V of CHIKV?

Methodology and findings: We infected orally both species with the variant E1-226V and estimated the infection, the viral dissemination, and the transmission rate by real time RT-PCR. Additionally, we used an in vitro assay to determine the amount of virus delivered by mosquitoes in their saliva. We found that Ae. aegypti as well as Ae. albopictus ensured a high replication of the virus which underwent an efficient dissemination as detectable in the salivary glands at day 2 post-infection (pi). Infectious CHIKV particles were delivered by salivary glands from day 2 with a maximum at day 6 pi for Ae. albopictus (10(3.3) PFU) and day 7 pi for Ae. aegypti (10(2.5) PFU).

Conclusions: Ae. albopictus is slightly more efficient than Ae. aegypti to transmit the variant E1-226V of CHIKV. These results will help to design an efficient vector control to limit transmission as soon as the first human cases are diagnosed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aedes / genetics*
  • Aedes / virology*
  • Alphavirus Infections / transmission
  • Alphavirus Infections / virology*
  • Animals
  • Chikungunya virus / genetics*
  • Chikungunya virus / metabolism*
  • Female
  • Genome, Viral
  • Genotype
  • Glycoproteins / genetics
  • Insect Vectors / genetics
  • Microscopy, Fluorescence / methods
  • Reverse Transcriptase Polymerase Chain Reaction
  • Saliva / virology
  • Salivary Glands / virology


  • Glycoproteins