Aedes albopictus (Diptera: Culicidae) Population Size Survey in the 2007 Chikungunya Outbreak Area in Italy. I. Characterization of Breeding Sites and Evaluation of Sampling Methodologies

Abstract

The population of Aedes albopictus (Skuse) (Diptera: Culicidae) was measured in four towns in northern Italy by means of Stegomyia indices (house index: percentage of houses with at least one active breeding site; container index: percentage of containers with larvae; and Breteau index: number of active breeding sites per premises), pupae per premises index (PPI), pupae per hectare index (PHI), and ovitrap monitoring. A detailed investigation on types and number of productive or potential larval habitats in the inspected premises was performed. Catch basins were the most productive breeding sites in both private and public areas. The influence of the premises maintenance and premises shading indices (PMI and PSI) on the population indices and the correlations between the latter and egg density were assessed. The highest PPI was found in badly maintained premises, most times combined with shady coverage. Stegomyia indices and PPI were well correlated with each other, but not with the PHI, which also included the pupae collected in public areas. We obtained a highly positive correlation (R = 0.86) between the PHI and weekly mean egg density estimated 7-14 d after inspection of the premises. The number of females per hectare, calculated using the Focks model, was correlated with the mean egg density of the week after sampling (R = 0.79), and we propose that ovitrap monitoring can be used to evaluate the efficiency of the control activities or to determine a mean egg density threshold for epidemic risk evaluation.

Pilot Field Trials With <I>Aedes albopictus</I> Irradiated Sterile Males in Italian Urban Areas

“…Aedes albopictus (Skuse) is an invasive species rapidly spreading and establishing in a number of countries with different climates (Benedict et al 2007) and it is known to be an efÞcient vector of many arboviruses causing human diseases, including yellow fever (family Flaviridae, genus Flavivirus, YFV), dengue (family Flaviviridae, genus Flavivirus, DENV), and Chikungunya (family Togaviridae, genus Alphavirus, CHIKV), in tropical as well as in temperate regions (Carrieri et al 2011a). Moreover, Ae.…”

Mapping of Aedes albopictus Abundance at a Local Scale in Italy

“…This can be explained by the presence of numerous man-made containers, which are the main sources of Ae. albopictus populations in urban or peri-urban environments [51]. Urbanization has been related to an increase in the larval habitats, mosquito density, larval development rate, and adult survivorship of Ae.…”

“…Other methods, such as ovitrap collections or a pupal survey, have been recommended to estimate IMS abundance [27,28]. In the Emilia-Romagna region of Italy, Carrieri et al [51,60] demonstrated a positive correlation between the number of Ae. albopictus eggs collected in ovitraps, female density estimated by a pupal survey, and human landing collections (HLC); and in Rome, Italy, Manica et al [61] estimated an increase of one biting female per person collected by HLC for every five additional eggs observed in ovitraps.…”

Cases of chikungunya virus infection in travellers returning to Spain from Haiti or Dominican Republic, April-June 2014

“…Ae. albopictus, the other vector, is already established in various countries in Europe, such as Italy, the south of France and some regions in Spain [26,[27][28][29]. In Spain, the mosquito is found in most parts of Catalonia, the region where most of our cases (9/10) were residing, and in the Baleares islands as well as some territories of Murcia and Valencia [26].…”