Dengue Virus 1 in Buenos Aires from 1999 to 2010: Towards Local Spread

Abstract

Dengue virus (DENV) is a public health problem representing the most important arthropod-borne viral disease in humans. In Argentina, Northern provinces have reported autochthonous cases since 1997, though these outbreaks have originated in bordering countries, where co-circulation of more than one serotype has been reported. In the last decade, imported dengue cases have been reported in Buenos Aires, the urban area of Argentina with the highest population density. In 2009, a dengue outbreak affected Buenos Aires and, for the first time, local transmission was detected. All cases of this outbreak were caused by DENV-1. In this report, we present the full-length sequences of 27 DENV-1 isolates, corresponding to imported cases of 1999–2000, as well as local and imported cases of the 2009 and 2010 outbreaks. We analyzed their phylogenetic and phylodynamic relationships and their global and local spread. Additionally, we characterized their genomic and phenotypic features. All cases belonged to DENV-1 genotype V. The most recent ancestor for this genotype was dated ∼1934, whereas that for the 2009 outbreak was dated ∼2007. The mean rates of nucleotide substitution were 4.98E-4 and 8.53E-4 subs./site/yr, respectively. We inferred an introduction from Paraguay in 1999–2000 and mainly from Venezuela during 2009–2010. Overall, the number of synonymous substitutions per synonymous site significantly exceeded the number of non-synonymous substitutions per site and 12 positively selected sites were detected. These analyses could contribute to a better understanding regarding spread and evolution of this pathogen in the Southern Cone of South America.

Dengue Virus 1 Outbreak in Buenos Aires, Argentina, 2016

“…We found no positively selected sites. The selection analysis resulted in an overall dN/dS of 0.05, which is consistent with our previous work on the 2009 outbreak sequences, where the overall dN/dS ratio was also <1 ( 4 ).…”

Understanding dengue virus evolution to support epidemic surveillance and counter-measure development

“…For example, a phylogeographic analysis of DENV2 American-Asian genotype in South America indicated a Southward dispersal of this serotype from the Caribbean [142]. This North-South axis of diffusion was also seen with Latin American epidemics of DENV-1 genotype V and DENV-3 genotype III [143–145] and perhaps offer a framework for prediction of the future routes of DENV lineage dispersal throughout this region. On a global scale there appears to be continental scale spatial structure of DENV genotypes, for instance only the American and American-Asian genotypes of DENV-2 have been detected in the Americas, and the DENV-2 Asian-I genotype is restricted to South East Asia [11,20] [146].…”

“…Studies in provincial Thailand were also able to describe epidemic dynamics within school-based cohorts within villages, with description of focal transmissions within and between schools and niche clustering within homes, all possible via genomic data analyses [160,161]. Titarelli et al identified both the dispersal epicenter and speed (km/hr) of DENV-1 epidemics within Buenos Aires itself [145]. Salje et al demonstrated a micro-spatial structure with individual DENV transmission chains in Thailand to a resolution of 200 meters, consistent with the limited vector flight range and local human mobility in many DENV endemic populations and suggestive that the majority of DENV infections occur close to a case’s home [151].…”

Spatio‐temporal distribution of vertically transmitted dengue viruses by Aedes aegypti (Diptera: Culicidae) from Arroyo Naranjo, Havana, Cuba

“…Although DENV‐2 was detected by RT‐PCR, we failed to obtain quality sequences. DENV‐1 sequences displayed 99‐100% nucleotide identity with strains grouped into genotype V (Accession numbers: , ). DENV‐3 sequence displayed 98% nucleotide identity with genotype III strains (Accession numbers: , ), while DENV‐4 sequence displayed 99% nucleotide identity with genotype II strains (Accession numbers: , ).…”