Seasonal dynamics of Aedes aegypti (Diptera: Culicidae) in the northernmost state of Brazil: a likely port-of-entry for dengue virus 4.
Roraima is the northernmost state of Brazil, bordering both Venezuela and Guyana. Appropriate climate and vector conditions for dengue transmission together with its proximity to countries where all four dengue serotypes circulate make this state, particularly the capital Boa Vista, strategically important for dengue surveillance in Brazil. Nonetheless, few studies have addressed the population dynamics of Aedes aegypti in Boa Vista. In this study, we report temporal and spatial variations in Ae. aegypti population density using ovitraps in two highly populated neighbourhoods; Centro and Tancredo Neves. In three out of six surveys, Ae. aegypti was present in more than 80% of the sites visited. High presence levels of this mosquito suggest ubiquitous human exposure to the vector, at least during part of the year. The highest infestation rates occurred during the peak of the rainy seasons, but a large presence was also observed during the early dry season (although with more variation among years). Spatial distribution of positive houses changed from a sparse and local pattern to a very dense pattern during the dry-wet season transition. These results suggest that the risk of dengue transmission and the potential for the new serotype invasions are high for most of the year.
Codeço
Cláudia Torres
CT
Programa de Computação Científica-Fiocruz, Instituto Oswaldo Cruz-Fiocruz, 21045-900 Rio de Janeiro, Brasil. codeco@fiocruz.br
Honório
Nildimar Alves
NA
Ríos-Velásquez
Cláudia M
CM
Santos
Maria da Conceição Alves dos
Mda C
Mattos
Ingrid Vieira de
IV
Luz
Sérgio Bessa
SB
Reis
Izabel Cristina
IC
Cunha
Guilherme Bernardino da
GB
Rosa-Freitas
Maria Goreti
MG
Tsouris
Pantelis
P
Castro
Márcia Gonçalves de
MG
Hayd
Ramão Luciano Nogueira
RL
Luitgards-Moura
José Francisco
JF
D000330:Aedes / Q000502:physiology*; D000818:Animals; D001938:Brazil; D003715:Dengue / Q000635:transmission*; D003716:Dengue Virus / Q000145:classification*; D006801:Humans; D007303:Insect Vectors / Q000502:physiology*; D010270:Parasite Egg Count; D011156:Population Density; D011157:Population Dynamics; D011159:Population Surveillance; D012307:Risk Factors; D012621:Seasons