ISCEP 2026 At Sunway Putra Hotel 17-18 August 2026
ABSTRACT
ORAL PRESENTATION ABSTRACT
T3.01
EVALUATION OF VECTOBACⓇ WG, A WATER- DISPERSIBLE BACTERIAL LARVICIDE FORMULATION, FOR THE CONTROL OF ANOPHELINE AND CULICINE (ORDER: DIPTERA) MOSQUITO VECTORS IN SARAWAK, MALAYSIA
Rezal BOHARI, Siti Fatimah SAMSUDIN, Richard NYALAU², Tze Yong LOO³, Micheal PELITINI", Teh Jo HUN'
Sibu Divisional Health Ofice. S
Ser
'Dept of Cnity Medicine and Public Health Facolty of Medicine and Health Sciences, Universi Malaysia Sarawak Kota Samarahan Sara "[email protected]
ABSTRACT
Larviciding is a supplementary tool for malaria control in Malaysia; however, standardised operational guidelines remain limited. This study evaluated the efficacy of VectoBac WG (B1) dosages at 500 and 1000 grams per hectare, dispersed via a STIHL SR420 mist blower, on the suppression of anopheline and culicine larvae in the Kapit district, Sarawak. A three-phase trial involving eight permanent pools was monitored weekly for four months. The pools were located within a 100-metre distance from the local community Pools used for Bti treatment in Phase 1 were used as controls in Phase 2 and were alternated again in Phase 3. Larval populations were quantified using a standard dipper across 10-15 fixed sampling spots per pool; populations were determined before treatment, as well as 24 hours and 7 days post- treatment. The study focused on the impact of Bti treatment on the L3/L4 stages, as these are more likely to develop into the next generation of adults compared to the L1/L2 stages. In Phase 1, the 500 g/ha and 1000 g/ha dosages achieved a significant 100% larval reduction within 24 hours compared to the control (p<0.05). In Phases 2 and 3, the 500 g/ha rate maintained a 98.9%-100.0% reduction. Post-treatment densities remained statistically stable after a one-week non-intervention period (pa006), with Spearman's correlation confirming that larval reduction was entirely independent of rainfall (p>0.05). Cost-effectiveness analysis identified the 500 g/ha dosage as optimal, yielding an Incremental Cost-Effectiveness Ratio (CER) of RM 9.07 for anophelines per percentage of reduction. In conclusion, an operational dosage of 500 g/ha ensures immediate, maximum larval suppression. However, its shart one- week efficacy necessitates integrated deployment within existing Malaysian malaria control strategies.
Keywords: Vector WG, larvicides, anaphalines, cucines, malaria, Sara
INTERNATIONAL SCIENTIFIC CONFERENCE ON ENTOMOLOGY AND PEST SCP) 2005