| dc.description.abstract | Accurate identification of epidemiologically important types of larval habitats is
considered an essential step in the targeted control of Aedes aegypti; an important vector
for several arboviruses, including dengue and chikungunya viruses. This study
determined larval habitats-specific Ae. aegypti productivity in selected habitats in
Msambweni, Kwale County, Kenya. The number of Ae. aegypti immatures in 83
representative larval habitats were counted daily for 30 days during the wet and dry
seasons. All pupae were removed and allowed to emerge in the laboratory. A total of
664 potential larval habitats were identified and classified based on their use and
material into seven habitat types, including: buckets, drums, jerrycans, pots, small
domestic containers (SDC), tires and others during the habitat census survey. Of 664
larval habitats examined, 144 larval habitats (21.7%) were infested with Aedes aegypti
larvae. 71% of the pupae were collected from tires and pots, both of which representing
17% of the habitats. On the other hand, buckets and SDC represented 55% of the total
habitats with an infestation rate of 11.8%, yet only 13.5% of the pupae were found in
them. Multivariate analysis showed that only habitat type and ability of the habitat to
be moved were associated with pupal abundance. During the 30-day daily pupal
production studies, only a few habitats were persistently found harboring pupae. In the
wet season, pupae were collected from 28% (23/83) of the larval habitats. In the dry
season, only 12% (10/83) of the habitats were ever found with pupae during the 30-day
sampling period, with three habitats accounting for 80% of all the pupae collected.
Three drums with 35% (127/365), 33% (121/365) and 12% (45/365) pupae respectively.
The results of the multivariate models for the risk factors of pupal productivity showed
that habitat type, placing of larval habitats in the backyard (IRR = 0.55; 0.35, 0.86), larval
habitats with without purpose (IRR = 2.62; 2.18, 3.14) and rainwater (IRR = 2.33; 1.69,
3.23) were the important predictors of larval habitat productivity during the wet season.
Although the multivariate model for habitat type did converge, habitat type and large size larval habitats (IRR=0.05 0.005, 0.56) were the only important predictors during the
dry season. In conclusion, drums, pots and tires covered more than 85% of Ae. aegypti
pupae; reinforcing the ‘key containers concept.’ Larval habitat characteristics and
human behavior can be used to predict entomological risk. Targeting these three types
of habitats makes epidemiological sense, especially during the dry season in the study
area | en_US |
