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Leishmania infantum is a protozoan parasite causing severe vector-borne visceral diseases both in humans and dogs. The latter are the most important natural reservoir and therefore should be the main target of control measures. The real efficacy of seropositive dogs culling as a direct control method is still debated, and the new sensitivity of large part of population considers ethically unacceptable this kind of approach. Treatment of infectious dogs with one of the available therapeutic protocols is recommendable as it allows to reduce parasite burdens and therefore the possibility of transmission of Leishmania infantum to vectors. Vaccination has been proven to be a very effective control tool, but the absence of a commonly recognized diagnostic method able to distinguish vaccinate from seropositive individuals is still an important limit. Concerning indirect control methods, a number of studies have demonstrated the efficacy of topical insecticides treatment (collars, spot-on, and sprays) in reducing incidence and prevalence of L. infantum. Also, the reduction of the odds of seroconversion in humans in endemic areas has been reported after the application of indirect control measures on dogs. The contemporary use of direct and indirect methods is even more effective in reducing seroprevalence in dogs.

In 2012 a US multistate outbreak of listeriosis was linked to ricotta salata imported from Italy, made from pasteurized sheep's milk. Sampling activities were conducted in Italy to trace the source of Listeria monocytogenes contamination. The cheese that caused the outbreak was produced in a plant in Apulia that processed semi-finished cheeses supplied by five plants in Sardinia. During an 'emergency sampling', 179 (23·6%) out of 758 end-products tested positive for L. monocytogenes, with concentrations from <10 c.f.u./g to 1·1 × 106 c.f.u./g. Positive processing environment samples were found in two out of four processing plants. A 'follow-up sampling' was conducted 8 months later, when environmental samples from three out of six plants tested positive for L. monocytogenes and for Listeria spp. PFGE subtyping showed 100% similarity between US clinical strains and isolates from ricotta salata, confirming the origin of the outbreak. The persistence of strains in environmental niches of processing plants was demonstrated, and is probably the cause of product contamination. Two PFGE profiles from clinical cases of listeriosis in Italy in 2011, stored in the MSS-TESSy database, were found to have 100% similarity to one PFGE profile from a US clinical case associated with the consumption of ricotta salata, according to the US epidemiological investigation (sample C, pulsotype 17). However, they had 87% similarity to the only PFGE profile found both in the US clinical case and in 14 ricotta cheese samples collected during the emergency sampling (sample B, pulsotype 1). Sharing of molecular data and availability of common characterization protocols were key elements that connected the detection of the US outbreak to the investigation of the food source in Italy. Simultaneous surveillance systems at both food and human levels are a necessity for the efficient rapid discovery of the source of an outbreak of L. monocytogenes.