Spatial Clustering of Aedes aegypti (Diptera: Culicidae) and Its Impact on Entomological Surveillance Indicators

Spatial clustering of Aedes aegypti (L.) was assessed in 0.25-km(2) sampling plots located in three different neighborhoods in the city of Rio de Janeiro, Brazil Monitoring was carried out with two oviposition traps (collecting either. eggs or adult mosquitoes) over a consecutive 80-wk period. Taylor power laws (TPL) were used to assess clustering in both adult and egg collections. The clustering level observed in both TPL models was sufficient to increase by two to three times the sampling effort required to achieve a desired precision of population estimates of egg and adults collections, respectively. The relationship between positivity and density indices was also affected by this clustering level, and virtually no changes in positivity data were observed for variations of adult densities over two mosquitoes per trap. General TPL model parameterizations for dealing with clustering of egg and adult populations of Ae. aegypti are proposed. Accounting for clustering-related issues is necessary for an appropriate design and interpretation of trap-based entomological surveillance data.