Dry Season Production of Filariasis and Dengue Vectors in American Samoa and Comparison with Wet Season Production

Aedes polynesiensis and Ae. aegypti breeding site productivity in two American Samoa villages were analyzed during a dry season survey and compared with a wet season survey. Both surveys identified similar container types producing greater numbers of pupae, with buckets, drums, and tires responsible for > 50% of Aedes pupae during the dry season. The prevalence of containers with Ae. polynesiensis and the density of Ae. polynesiensis in discarded appliances, drums, and discarded plastic ice cream containers were significantly greater during the dry season. Aedes aegypti pupal densities were significantly greater in the dry season in ice cream containers and tires. Significant clustering of the most productive container types by household was only found for appliances. The high productivity for Ae. polynesiensis and Ae. aegypti pupae during the wet and dry seasons suggests that dengue and lymphatic filariasis transmission can occur throughout the year, consistent with the reporting of dengue cases.