Abstract:
The Premises of the University of Sri Jayewardenepura was surveyed in the
month of May for possible breeding habitats of mosquitoes which were
mapped out and the immature stages of collected were identified.
Subsequently investigations were made by placing ovitraps within the
University premises from June to November 2008, to determine the
abundance of Aedes aegyp ti and Aedes albopictus detected during the
previous survey in the month of May. An Ae.aegypti positive container was
detected only once in all the indoor and outdoor container observed and no
Ae.aegypti positive ovitrap was recorded during the study period .. The
Ovitrap Index (01) for Ae.albopictus was calculated monthly. Breeding of
Ae.albopictus was found in both indoor (Mean Monthly 01 =13.3) and out
door containers (Mean Monthly 01 35.3). During the dry season the rainfall
recorded a monthly range of 45.6 mm to 152.6mm. The larval population of
Ae.albopictus remained low during this period with an 01 range from 0 to
12.5. However, during the rainy season which showed a monthly range of
294.9mm to 414.4mm, the 01 increased exponentionally (01 ranges from
13.3-80). In the month of September, Ae.albopictus were recorded in indoor
ovitraps too (01=13.3), indicating its ability to replace the breeding places of
Ae.aegypti, under certain environmental conditions. The monthly dengue
incidence reported from the neighboring area declined in the month of
August and started to increase again in the month of September. The
ecological conditions in theses areas are very much similar to those within
the University premises. The 01 values of dengue vector mosquito species
could be utilized to indicate a potential increase in the dengue incidence.
