Applicability and feasibility of systematic review for performing evidence-based risk assessment in food and feed safety.

Food and feed safety risk assessment uses multi-parameter models to evaluate the likelihood of adverse events associated with exposure to hazards in human health, plant health, animal health, animal welfare, and the environment. Systematic review and meta-analysis are established methods for answering questions in health care, and can be implemented to minimize biases in food and feed safety risk assessment. However, no methodological frameworks exist for refining risk assessment multi-parameter models into questions suitable for systematic review, and use of meta-analysis to estimate all parameters required by a risk model may not be always feasible. This paper describes novel approaches for determining question suitability and for prioritizing questions for systematic review in this area. Risk assessment questions that aim to estimate a parameter are likely to be suitable for systematic review. Such questions can be structured by their "key elements" [e.g., for intervention questions, the population(s), intervention(s), comparator(s), and outcome(s)]. Prioritization of questions to be addressed by systematic review relies on the likely impact and related uncertainty of individual parameters in the risk model. This approach to planning and prioritizing systematic review seems to have useful implications for producing evidence-based food and feed safety risk assessment.

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.

A systematic review of the efficacy of prophylactic control measures for naturally-occurring canine leishmaniosis, part I: vaccinations.

Canine leishmaniosis (CanL) is an important zoonotic disease; however, the efficacy of available vaccines for the prevention of naturally-occurring Leishmania infantum (L. infantum) infection in dogs remains unclear. The objective of this review was to determine the efficacy of currently available vaccines to prevent naturally-occurring L. infantum infection in dogs. Four bibliographic databases (CAB Direct 2011, Web of Science 2011, U.S. National Library of Medicine 2011 and Literatura Latino Americana e do Caribe em Ciências da Saúde) were searched along with eight sets of conference proceedings and the International Veterinary Information Service (IVIS) database, from 1980 to November 2012. Randomised controlled trials (RCTs), non-randomised clinical trials (NRCTs), cohort studies and case-control studies that investigated vaccine 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 was conducted for all mitigations for CanL and yielded the title and abstract of 937 articles, from which 84 articles were screened based on full text. Twelve studies on vaccinations (five RCTs, seven NRCTs) were identified. Ten studies were at a high risk of methodological shortcomings, whilst two were at an unclear risk. The use of 200 µg ALM protein, Leishmune(®), CaniLeish(®), LiESAp with MDP, and ALM with BCG tended to significantly reduce the proportion of dogs infected with L. infantum based on either parasitological or serological evidence. The use of lyophilized protein vaccine significantly increased the proportion of dogs infected with L. infantum based on either parasitological or serological evidence. There is peer-reviewed evidence that control measures are effective in preventing CanL with the results suggesting that between 6 and 54% of infections could be prevented with vaccination. However, this evidence is based on a small number of RCTs, all of which are either at high or unclear risk of methodological shortcomings. Well-designed, adequately powered and properly reported randomised clinical trials are needed to clearly establish efficacy of vaccines as CanL control measures.