METHODS: Data on dengue infection were extracted from the dengue database of the state of Sabah from 2013 through 2018. DENV NS-1-positive serum samples from multiple sites throughout Sabah were sent to the state public health laboratory, Kota Kinabalu Public Health Laboratory, for serotype determination. The analysis of factors associated with severe dengue was determined from the data of 2018 only.

RESULTS: In 2013, there were 724 dengue cases; however, from 2014, dengue cases increased exponentially and resulted in 3423 cases in 2018. Increasing dengue cases also led to increased dengue mortality. The number of dengue deaths in 2013 was only five which then gradually increased, and in 2018, 29 patients died. This is an increase of 580% from 2013 to 2018. Deaths were considerably more in the districts of the east coast of Sabah compared with districts in the west coast. During the study period, all DENV serotypes could be identified as serotypes circulating in Sabah. In 2018, the predominant serotype was DENV-3. The monthly peak of dengue infection varied in different years. In the logistic regression analysis, it was identified that children were 6.5 times, patients infected with mixed serotype of DENV were 13 times, and cases from the districts of the east coast were 5.2 times more likely to develop severe dengue.

Methods: : Extensive surveys were carried out from November 2017 to January 2018 (post-monsoon season) randomly in the nine inhabited islands of Lakshadweep for conducting faunastic studies on mosquitoes and to know the basic binomics like breeding and resting preference of mosquitoes. The study islands included, Kavaratti, Agatti, Chetlat, Bitra, Amini, Kadmath, Andrott, Kalpeni and Kiltan. Both immature and adult collections were carried out by standard/appropriate sampling techniques. The obtained data were calculated and analysed in terms of different entomological indices.

Results: : A total of 3356 mosquitoes were collected during the study period which comprised of 16 species from nine genera. Out of the 16 species, six belonged to mosquito vectors. The collection included malaria vector, Anopheles stephensi; Japanese encephalitis vector, Culex tritaeniorhynchus; Bancroftian filariasis vector, Cx. quinquefasciatus; Brugian filariasis vector, Mansonia uniformis; and dengue and chikungunya vectors, Stegomya albopicta and St. aegypti. Stegomya albopicta was the most predominant species observed constituting 54% of the catch, followed by Cx. quinquefasciatus, An. stephensi, Cx. tritaeniorhynchus, and St. aegypti constituting 10.5, 6, 3 and 1.2%, respectively. Apart from vector species many non-vectors such as Heizmannia chandi, An. subpictus, An. varuna, Cx. sitiens, Cx. minutissimus, Cx. rubithoracis, Fredwardsius vittatus, Lutzia fuscana, Malaya genurostris and Armigeres subalbatus were also present in the study area. In Kavaratti Island, the capital of Lakshadweep, a non-vector species of sandfly, Sergentomyia (Parrotomyia) babu was observed during the indoor resting collection. The major breeding sites which supported various mosquito species included, discarded plastic containers, tree holes, open sintex tanks (water storage tanks), unused wells, discarded tyres, discarded iron pots, unused and damaged boats, cement tanks, pleated plastic sheets, coral holes, pits and irrigation canals, discarded washing machines, and Colocasia plant leaf axils. Breteau index ranged between 65.3 and 110, CI ranged between 63.64 and 72.41; and HI ranged between 38.46 and 70 among the various islands.