Are Aedes albopictus or other mosquito species from northern Italy competent to sustain new arboviral outbreaks

• Published in: Medical and veterinary entomology Vol. 24; no. 1; pp. 83 - 87
• Main Authors: TALBALAGHI, A, MOUTAILLER, S, VAZEILLE, M, FAILLOUX, A.-B
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.03.2010; Blackwell Publishing Ltd; Wiley
• Subjects: Aedes; Aedes - growth & development; Aedes - virology; Aedes albopictus; Aedes vexans vexans; Alphavirus Infections; Alphavirus Infections - epidemiology; Alphavirus Infections - transmission; Alphavirus Infections - virology; Animals; Anopheles maculipennis; arboviruses; chikungunya; Chikungunya virus; Chikungunya virus - genetics; Chikungunya virus - growth & development; Culex pipiens; Culicidae; Dengue; Dengue - epidemiology; Dengue - transmission; Dengue - virology; Dengue Virus; Dengue Virus - genetics; Dengue Virus - growth & development; Diptera; Disease Outbreaks; disseminated infection rates; Female; Humans; infection; Insect Vectors; Insect Vectors - growth & development; Insect Vectors - virology; Italy; Italy - epidemiology; Life Sciences; Microbiology and Parasitology; mosquito-borne diseases; Reverse Transcriptase Polymerase Chain Reaction; RNA, Viral; RNA, Viral - chemistry; RNA, Viral - genetics; salivary glands; vector competence; viral diseases of animals and humans; Viral Load; Virology; virus replication; virus transmission; Italy; Italy, Emilia-Romagna, Ravenna; Southeast Asia
• ISSN: 0269-283X; 1365-2915
• DOI: 10.1111/j.1365-2915.2009.00853.x

The Asian tiger mosquito Aedes albopictus (Skuse) (Diptera: Culicidae), native to Southeast Asia, has extended its geographical distribution to invade new temperate and tropical regions. This species was introduced in 1990 to Italy and has since become the main pest in urban settings. It was incriminated as a principal vector in the first European outbreak of chikungunya virus (CHIKV) in the province of Ravenna (Italy) in 2007. This outbreak was associated with CHIKV E1-226V, efficiently transmitted by Ae. albopictus. The occurrence of this outbreak in a temperate country led us to estimate the potential of Ae. albopictus to transmit CHIKV and dengue virus (DENV), and to determine the susceptibility to CHIKV of other mosquito species collected in northern Italy. Experimental infections showed that Ae. albopictus exhibited high disseminated infection rates for CHIKV (75.0% in Alessandria; 90.3% in San Lazzaro) and low disseminated infection rates for DENV-2 (14.3% in San Lazzaro; 38.5% in Alessandria). Moreover, Ae. albopictus was able to attain a high level of viral replication, with CHIKV detectable in the salivary glands at day 2 after infection. In addition, the other three mosquito species, Anopheles maculipennis Meigen, Aedes vexans vexans (Meigen) and Culex pipiens L., showed variable susceptibilities to infection with CHIKV, of 0%, 7.7% and 0-33%, respectively. This information on vector competence is crucial in assessing the risk for an outbreak of CHIKV or DENV in Italy.