Field Efficacy of Larvivorous Fish and Pyriproxyfen Combined with Community Engagement on Dengue Vectors in Cambodia: A Randomized Controlled Trial.

Abstract

Evidence on the effectiveness of low-cost, sustainable biological vector control tools for Aedes mosquitoes is limited. Therefore, the purpose of this trial was to estimate the impact of guppy fish in combination with the larvicide pyriproxyfen (PPF) (Sumilarv® 2MR) and communication for behavioral impact (COMBI) activities to reduce entomological indices in Cambodia. In this cluster randomized, controlled superiority trial, 30 clusters comprised of one or more villages each was allocated in a 1:1:1 ratio to receive either 1) all three interventions (guppies, PPF, and COMBI), 2) two interventions (guppies and COMBI), or 3) control (standard vector control). Entomological surveys among 40 randomly selected households per cluster were carried out quarterly. The primary outcome was the population abundance of adult female Aedes mosquitoes trapped using adult resting collections. In the primary analysis, adult female Aedes abundance and mosquito infection rates was aggregated over follow-up time points to give a single rate per cluster. These data were analyzed by negative binomial regression, yielding abundance ratios (ARs). The number of Aedes females was reduced roughly by half compared with the control in both the guppy, PPF, and COMBI arm (AR = 0.54; 95% CI, 0.34-0.85; P = 0.0073); and the guppy and COMBI arm (AR = 0.49; 95% CI, 0.31-0.77; P = 0.0021). The effectiveness demonstrated and extremely low cost of including fish rearing in community-based health structures suggest they should be considered as a vector control tool as long as the benefits outweigh any potential environmental concerns. Sumilarv® 2MR was also highly accepted and preferred over current vector control tools used in Cambodia.

• Authors: John Christian Hustedt, Dyna Doum, Vanney Keo, Sokha Ly, BunLeng Sam, Vibol Chan, Neal Alexander, John Bradley, Marco Liverani, Didot Budi Prasetyo, Agus Rachmat, Muhammad Shafique, Sergio Lopes, Leang Rithea, Jeffrey Hii
• Journal: The American journal of tropical medicine and hygiene (Am J Trop Med Hyg) Vol. 105 Issue 5 Pg. 1265-1276 (09 07 2021) ISSN: 1476-1645 [Electronic] United States
• PMID: 34491225 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Insecticides
• Pyridines

Topics

• Adolescent
• Adult
• Aedes (drug effects, virology)
• Aged
• Aged, 80 and over
• Animals
• Cambodia (epidemiology)
• Community Participation
• Dengue (epidemiology, prevention & control)
• Female
• Humans
• Insecticides (administration & dosage)
• Male
• Middle Aged
• Mosquito Control (methods)
• Mosquito Vectors (drug effects)
• Pest Control, Biological
• Poecilia
• Pyridines (administration & dosage)
• Young Adult