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Listeria monocytogenes is a foodborne pathogen that can produce serious, even fatal, infections. Among other foods, it can be found in unpasteurized dairy and ready-to-eat products. Surveillance of L. monocytogenes is of great interest since sources of infection are difficult to determine due to the long incubation period, and because the symptoms of listeriosis are similar to other diseases. We performed a genomic study of L. monocytogenes isolated from fresh cheeses and clinical samples from Ecuador. Sixty-five isolates were evaluated and sequenced, 14 isolates from cheese samples and 20 from clinical listeriosis cases from the National Institute of National Institute of Public Health Research, and 31 isolates from artisanal cheese samples from 8 provinces. All isolates exhibited heterogeneous patterns of the presence of pathogenicity islands. All isolates exhibited at least 4 genes from LIPI-1, but all references (26 L. monocytogenes closed genomes available in the NCBI database) showed the complete island, which encompasses 5 genes but is present in only two Ecuadorian isolates. Most isolates lacked gene actA. Genes from LIPI-2 were absent in all isolates. LIPI-3 and LIPI-4 were present in only a few references and isolates. With respect to the stress survival islets, our samples either presented SSI-1 or SSI-F2365, except for one isolate that presented SSI-F2365 and also one gene from SSI-1. None of the samples presented SSI-2. The predominant ST (sequence type) was ST2 (84.62% 55/65), and the only ST found in food (93.33% 42/45) and clinical samples (65% 13/20). Isolates were not grouped according to their sampling origin, date, or place in a phylogenetic tree obtained from the core alignment. The presence of ST2 in food and clinical samples, with high genomic similarity, suggests a foodborne infection risk linked to the consumption of fresh cheeses in Ecuador.

The pygmy marmoset (Cebuella pygmaea) is the smallest platyrrhine primate. It lives in gallery forests in the Upper Amazon basin of Colombia, Ecuador, Peru, Bolivia and Brazil. Although all the Ecuadorian primate species are threatened by human activities, the pygmy marmoset is one of the most vulnerable due to its high specialization in diet and habitat. It is included in the list of vulnerable species in Ecuador. Anthropogenic alteration of the habitats is a stress factor for pygmy marmosets. In this context this study aimed to establish a protocol to measure cortisol concentration in feces (ng/g), as an indicator of the stress level of the individuals, and to make a preliminary comparison of the levels of cortisol and stress of three populations of pygmy marmosets in Amazonian Ecuador. Fifty two fecal samples from the wild populations of Tiputini and San Pablo, and one captive population from Puyo were analyzed. The samples analyzed had a dry weight between 0.05 and 0.07 g. The biological validation made with the fecal samples of an individual quarantined, showed that cortisol levels were higher in times closer to its death. The preliminary results suggest that the captive population from Puyo has higher levels of stress than the wild populations. These results have to be confirmed by analyzing a larger number of samples with information about the time of fecal deposition, the sex, age and previous activities of the individuals.