A study published in Parasites & Vectors on 27 September 2026 by the University of the West Indies, Jamaica’s Ministry of Health and Wellness and the US CDC shows that Aedes aegypti from both urban (Kingston and St Andrew) and rural (Lances Bay, Hanover) Jamaica resist several insecticide classes: permethrin, deltamethrin and malathion.
Main points
- In CDC bottle bioassays at the 30-minute diagnostic time, the urban Kingston – St Andrew population showed 0% mortality to permethrin, 22.0% ± 2.7% to deltamethrin and 70.5% ± 9.8% to malathion.
- The rural Hanover population was even more resistant: 0% mortality to permethrin and malathion and only 8.1% ± 2.6% to deltamethrin. Aedes albopictus from Kingston – St Andrew was also resistant to deltamethrin, with mortality below the CDC susceptibility threshold.
- Transcriptomic analysis showed strong overexpression of detoxification and cuticle-associated genes after malathion exposure; pyriproxyfen (an insect growth regulator) caused a moderate but broad response involving metabolic and endocrine pathways.
- The authors conclude that resistance in Jamaica is widespread, heterogeneous and dynamic, and that local resistance surveillance and integrated vector management are needed, not reliance on pyrethroids alone.
VPMA’s note
The results show that the same mosquito species can have very different resistance levels between urban and rural areas and between insecticide classes. Members who use pyrethroid and organophosphate products against mosquitoes should follow the resistance surveillance results of local preventive health agencies, rotate active ingredients in line with technical guidance and combine treatments with larval control and breeding-site removal.
- Source
- Parasites & Vectors – Phenotypic insecticide resistance in Jamaican Aedes spp. and resistance-associated transcripts in Aedes aegypti
- Published
- 27 September 2026
- Section
- Research · Insects, Chemicals
- Journal
- Parasites & Vectors (open access)
- DOI
- 10.1186/s13071-026-07666-w
Source: Parasites & Vectors – Phenotypic insecticide resistance in Jamaican Aedes spp. and resistance-associated transcripts in Aedes aegypti (summarised in English by VPMA). Read the Vietnamese page.