Abstract
BackgroundAedes aegypti is extensively spread throughout South America where it has been responsible for large dengue epidemics during the last decades. Intriguingly, dengue transmission has not been reported in Uruguay and is essentially prevalent in subtropical northern Argentina which borders Uruguay.MethodsWe assessed vector competence for dengue virus (DENV) of Ae. aegypti populations collected in subtropical Argentina (Corrientes) as well as temperate Uruguay (Salto) and Argentina (Buenos Aires) in 2012 using experimental oral infections with DENV-2. Mosquitoes were incubated at 28°C and examined at 14 and 21 days p.i. to access viral dissemination and transmission. Batches of the Buenos Aires mosquitoes were also incubated at 15°C and 20°C.ResultsAlthough mosquitoes from temperate Uruguay and Argentina were competent to transmit DENV, those from subtropical Argentina were more susceptible, displaying the highest virus titters in the head and presenting the highest dissemination of infection and transmission efficiency rates when incubated at 28°C. Interestingly, infectious viral particles could be detected in saliva of mosquitoes from Buenos Aires exposed to 15°C and 20°C.ConclusionsThere is a potential risk of establishing DENV transmission in Uruguay and for the spread of dengue outbreaks to other parts of subtropical and temperate Argentina, notably during spring and summer periods.
Highlights
Aedes aegypti is extensively spread throughout South America where it has been responsible for large dengue epidemics during the last decades
The ACO population from northern subtropical Argentina performed the best measures of disseminated infection rate (DIR), transmission rate (TR) and transmission efficiency (TE) compared to the temperate populations from both Argentina (BUE) and Uruguay (SAL) when incubated at 28°C (Table 1)
The DIR determined by fluorescent assay of head homogenates on C6/36 cells varied from 53.3% (ACO, SAL) to 66.7% (BUE) at day 14 pi, and from 76.7% (ACO, SAL) to 78.8% (BUE) at day 21 pi
Summary
Aedes aegypti is extensively spread throughout South America where it has been responsible for large dengue epidemics during the last decades. Dengue transmission has been constant every summer from the center to the north of the country, but very few cases were confirmed by national health authorities: 81 cases of DENV-1, -2 in Santa Fe and Salta during 2011 [6] and 109 of DENV-2, -3 in La Rioja, Buenos Aires and Salta during 2012 [7]. Imported dengue cases have annually been recorded in Uruguay since the late 1990’s, with 80–200 annually diagnosed in the last seven years [10] These cases were due to DENV-1, acquired in Brazil and Paraguay, and DENV-1, -2 -3 imported from other South American countries [10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
