Comportamento de micro-organismos patogênicos durante processo de compostagem de carcaças de suínos

O processo de compostagem é uma prática importante para aceleração da decomposição de carcaças e inativação de patógenos potencialmente presentes no material a ser decomposto. No entanto, é necessário avaliar e promover o funcionamento adequado do processo. Diante disso, o presente estudo teve por objetivo avaliar a eliminação de micro-organismos patogênicos em composteiras construídas em escala laboratorial para decomposição de carcaças de suíno trituradas e em escala piloto para decomposição de carcaças de suíno em pedaços (picadas). Para isso, foram construídas composteiras em escala laboratorial e piloto, onde foram compostadas carcaças de suínos intercaladas com camadas de maravalha, umedecidas com água. A essas composteiras foram adicionadas concentrações conhecidas de micro-organismos patogênicos modelo (Escherichia coli e Salmonella Senftenberg). A redução destes micro-organismos foi acompanhada até a não detecção dos mesmos viáveis. Os resultados indicaram que as composteiras em escala piloto, devido às suas dimensões, atingiram as condições ideais de processo e eliminaram de forma eficiente e mais rápida os patógenos (até 7 dias, quando a temperatura atingida foi acima de 60ºC). Desta forma, este processo é uma alternativa promissora para a destinação de carcaças de suínos se executado dentro de condições adequadas.

Genomic Evidence of Environmental and Resident Salmonella Senftenberg and Montevideo Contamination in the Pistachio Supply-chain

Pistachios have been implicated in two salmonellosis outbreaks and multiple recalls in the U.S. This study performed a retrospective data analysis of Salmonella associated with pistachios and a storage study to evaluate the survivability of Salmonella on inoculated inshell pistachios to further understand the genetics and microbiological dynamics of this commodity-pathogen pair. The retrospective data analysis on isolates associated with pistachios was performed from both short-read and long-read sequencing technologies. The sequence data were analyzed using the FDA’s Center for Food Safety and Applied Nutrition Single Nucleotide Polymorphism (SNP) analysis and Whole Genome Multi-locus Sequence Typing (wgMLST) pipeline. The storage study evaluated the survival of five strains of Salmonella on pistachios, both in a cocktail as well as individually. Our results demonstrate: i) evidence of persistent Salmonella Senftenberg and Salmonella Montevideo strains in pistachio environments, some of which may be due to clonal resident strains and some of which may be due to preharvest contamination; ii) presence of the Copper Homeostasis and Silver Resistance Island (CHASRI) in Salmonella Senftenberg and Montevideo strains in the pistachio supply chain; and iii) different serovars of Salmonella enterica, including Salmonella Senftenberg and Salmonella Montevideo, are able to survive in pistachios over an extended period of time.

Bali Belly: Salmonella senftenberg Found in an Infected Ovarian Endometrioma

Salmonella is an extremely rare cause of an infected endometrioma. We present a case of a 30-year-old immunocompetent woman presenting with fevers and abdominal pain, on a background of prior endometriosis. Initial antibiotic treatment for pelvic inflammatory disease failed, and the patient progressed to septic shock requiring surgical evacuation of an infected ovarian endometrioma. Microbiological samples from stool, ovary, and peritoneal fluid revealed infection with Salmonella senftenberg. The likely diagnosis was Salmonella enterocolitis with bacterial translocation to an ovarian endometrioma.

Pathogen Reduction Potential in Anaerobic Digestion of Organic Fraction of Municipal Solid Waste and Food Waste

Anaerobic digestion (AD) is a commonly used method of processing waste. Regardless of the type of the used digestate (fertilizer, feedstock in case of solid-state fermentation, raw-material in case of thermal treatment) effective pathogen risk elimination, even in the case of high pathogen concentration is essential. An investigation of the survival time and inactivation rate of the Salmonella Senftenberg W775, Enterococcus spp., and Ascaris suum eggs during thermophilic anaerobic digestion performed on laboratory scale and confirmation of hygienization in full-scale operation were performed in this study. Except for sanitization efficiency, the AD process performance and stability were also verified based on determination of pH value, dry matter content, acidity, alkalinity, and content of fatty acids. The elimination of pathogen was met within 6.06 h, 5.5 h, and about 10 h for the Salmonella Senftenberg W775, Enterococcus spp., and Ascaris suum, respectively in the laboratory trials. The obtained results were confirmed in full-scale tests, using 1500 m3 Kompogas® reactors, operating in MBT Plant located in Poland. Sanitization of the digestate was achieved. Furthermore, the process was stable. The pH value, suspended solids, and ammonium content remained stable at 8.5, 35%, and 3.8 g/kg, respectively. The acetic acid content was noted between almost 0.8 and over 1.1 g/kg, while the concentration of propionic acid was noted at maximum level of about 100 mg/kg. The AD conditions could positively affect the pathogen elimination. Based on these results it can be found that anaerobic digestion under thermophilic conditions results in high sanitation efficiency.

Testing a Nonpathogenic Surrogate Microorganism for Validating Desiccation-Adapted Salmonella Inactivation in Physically Heat-Treated Broiler Litter

ABSTRACT Thermal resistance of desiccation-adapted Salmonella Senftenberg 775W was compared with that of Enterococcus faecium NRRL B-2354 in aged broiler litter. Aged broiler litter with 20, 30, and 40% moisture contents was inoculated separately with desiccation-adapted Salmonella Senftenberg 775W and E. faecium NRRL B-2354 at ca. 5 to 6 log CFU/g and then heat treated at 75, 85, and 150°C. At all tested temperatures, desiccation-adapted E. faecium NRRL B-2354 was more heat resistant than desiccation-adapted Salmonella Senftenberg 775W (P < 0.05). During the treatments at 75 and 85°C, E. faecium NRRL B-2354 in aged broiler litter with all moisture contents was reduced by 2.89 to 4.12 log and was above the detection limit of direct plating (1.30 log CFU/g), whereas Salmonella Senftenberg 775W could not be detected by enrichment (>5-log reduction) during holding time at these temperatures. At 150°C, E. faecium NRRL B-2354 in aged broiler litter with 20 and 30% moisture contents was still detectable by enrichment after heat exposure for up to 15 min, whereas Salmonella Senftenberg 775W in aged broiler litter with all moisture contents could not be detected throughout the entire treatment. Our results revealed that E. faecium NRRL B-2354 can be used as a surrogate for Salmonella to validate the thermal processing of poultry litter by providing a sufficient safety margin. This study provides a practical tool for poultry litter processors to evaluate the effectiveness of their thermal processing.