A systematic review of the efficacy of prophylactic control measures for naturally occurring canine leishmaniosis. Part II: topically applied insecticide treatments and prophylactic medications.

The objective of this study was to systematically review the efficacy of topically applied insecticide treatments of dogs (impregnated collars, spot-ons), and prophylactic medications to prevent natural Leishmania infantum (L. infantum) infection in dogs. Randomised controlled trials (RCT), non-randomised clinical trials, cohort studies and case-control studies that investigated preventive efficacy for natural L. infantum infection in dogs were eligible for inclusion. Two review authors independently assessed each study against the inclusion criteria, independently extracted relevant data from all included studies and assessed the risk of methodological shortcomings in each individual study. The odds ratio (OR) and absolute risk reduction (ARR) for dichotomous outcomes and mean difference for continuous outcomes were calculated. Meta-analysis was not performed due to heterogeneity of the studies identified. The search yielded 937 articles, from which 84 full text articles were selected for second stage screening. Eleven eligible studies were included; four on collars (two RCTs), three on spot-ons (two RCTs - one looking at two different dosing regimens), three on prophylactic medications (all RCTs) and one on both collars and spot-ons summarised in this paper. All of the studies were considered to be at a high risk of methodological shortcomings, with the exception of one spot-on study which was considered to be at an unclear risk of methodological shortcomings. Deltamethrin collars, 65% permethrin, 10% imidacloprid with 50% permethrin spot-ons and domperidone prophylactic medication tended to significantly reduce the proportion of dogs infected with L. infantum based on either parasitological or serological evidence.