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In Latin America, nontyphoidal Salmonella (NTS) is one of the most important etiological agents of foodborne infections; it can survive in soil, water, and food even after processing. Here, we aime...

Salmonella enterica is among the most important foodborne pathogens. In Ecuador, there is limited information about non-typhoidal S. enterica occurrence in raw meats, its serotype distribution, and antimicrobial resistance. In this study, we addressed this issue in 1095 retail fresh meats (chicken, pork, veal, lamb, beef, and turkey) in Quito by performing a traditional culture methodology and molecular detection. We found that S. enterica was present in 38.1% of the samples, and Salmonella Infantis was the most common serotype showing a high antibiotic resistance and a wide host range. Some host-adapted serotypes were found in uncommon sources of meat, suggesting cross-contamination and the need to implement good manufacturing practices in meat processing. High levels of multidrug resistance were found in all serotypes. There is an urgent need to identify Salmonella serotypes in food to compare with clinical data and to carry out epidemiological studies to control and prevent outbreaks and infections.

Cervical cancer is the fourth most common type of cancer in women. Worldwide, it is a public health problem with around 604,127 women diagnosed per year and 341,831 deaths. Cervical cancer and persistent high-risk human papillomavirus (HPV) infection are highly associated. However, other factors are also involved, such as viral load, HPV variants, sexual behavior, and genetic factors. The host immune response against HPV has been widely studied and it has shown associations with development of cervical cancer. The human leukocyte antigen (HLA) genes are related to the persistence of HPV infection and progression to cervical cancer because of their role in controlling T-cell mediated immune response to clear the infection. In Ecuador, there is scarce information about HLA and HPV infection with high-risk genotypes in the population. This study aimed to identify host-specific HLA alleles in women with cervical intraepithelial neoplasia (CIN) II and III, and cancer infected with HPV-16, 58, and 52. In this study, we included 51 samples previously identified as positive for HPV-16, 58, and 52 from 12 Ecuadorian provinces. As a result, we found that HLA-A*02, HLA-B*35, HLA-C*04, HLA-DRB1*04, and HLA-DQB1*03 alleles were the most frequent, these alleles have been associated with cervical cancer in previous studies; nevertheless, we did not find a statistically significant association between HLA alleles, HPV genotype, and histopathological lesion. This is a baseline study to uncover possible relationships between HLA and HPV to elucidate why this virus can develop a persistent infection in some women leading to the development of cervical cancer.

Listeria monocytogenes is one of the most important bacteria associated with foodborne diseases, soft cheese being an important L. monocytogenes vehicle. In Ecuador, soft cheese is consumed in 84.3% of urban households. We determined the prevalence of L. monocytogenes and serogroups in 260 fresh artisanal soft cheese samples collected in 18 of 24 Ecuadorian provinces. Listeria spp. detection was carried out by culture-dependent and independent methods; 14.23% of samples were positive for L. monocytogenes. Serogroup IVb was found in 83.78% of the food isolates. Serogroups IIb and IIa were present in 8.11% of our isolates. To our knowledge, this is the first report of L. monocytogenes serogroups associated with food in Ecuador; we also found serogroup similarities between cheese isolates and clinical isolates.

Oropouche virus (OROV) is responsible for outbreaks of Oropouche fever in parts of South America. We recently identified and isolated OROV from a febrile Ecuadorian patient, however, a previously published qRT-PCR assay did not detect OROV in the patient sample. A primer mismatch to the Ecuadorian OROV lineage was identified from metagenomic sequencing data. We report the optimisation of an qRT-PCR assay for the Ecuadorian OROV lineage, which subsequently identified a further five cases in a cohort of 196 febrile patients. We isolated OROV via cell culture and developed an algorithmically-designed primer set for whole-genome amplification of the virus. Metagenomic sequencing of the patient samples provided OROV genome coverage ranging from 68–99%. The additional cases formed a single phylogenetic cluster together with the initial case. OROV should be considered as a differential diagnosis for Ecuadorian patients with febrile illness to avoid mis-diagnosis with other circulating pathogens., Author summary Oropouche virus (OROV) causes outbreaks of febrile illness in areas of South and Central America and we recently identified it in Ecuador for the first time, using metagenomic sequencing. The genome sequence data revealed that the Ecuadorian strain of the virus was not detected using a published qRT-PCR, as it differed genetically at the binding site of the reverse primer. To address this, we developed a modified qRT-PCR that showed increased sensitivity for the Ecuadorian strain. This test detected OROV infection in 6 out of 196 febrile patients from Esmeraldas, Ecuador in 2016. OROV was isolated from positive patient samples, viral genome sequences were compared to publicly available OROV sequences. This revealed that the Ecuadorian cases are genetically distinct, suggesting that local transmission of the virus should not be ruled out. This work highlights the need for a better understanding of OROV dynamics in Ecuador and surrounding areas, the importance of considering OROV as a cause of fever in Ecuadorian patients and the possibility of selectively using metagenomic sequencing in parallel to traditional molecular techniques in patient testing.

Summary Objectives Burkholderia cepacia has been linked to healthcare-associated infections and colonization caused by contamination of alcohol-free mouthwash used in patients undergoing mechanical ventilation. The purpose of our study was to establish the source of a clustering of healthcare-associated B. cepacia isolates in patients on mechanical ventilation in the intensive care unit (ICU). Methods During April 2012 the Infection Control Committee became concerned when B. cepacia was isolated from tracheal aspirate cultures of three ICU patients. The medical records for the years 2011 and 2012 were reviewed to identify further cases. Cultures of potential reservoirs were done. Isolates from patients and an alcohol-free mouthwash were submitted to multilocus sequence typing (MLST) analysis and antimicrobial resistance testing. Results Four patients with positive cultures for B. cepacia were identified before the review of the medical records for the years 2011 and 2012. Nine further cases were identified in the review, defined as a patient with pneumonia who had a culture of respiratory secretions that was positive for B. cepacia . Three were cases of infection and 10 were colonizations. All of the isolates from patients (J, K, L, and M) and mouthwash samples (B19, B20, and B21) were genetically identical by MLST analysis. Conclusions Our findings strongly suggest that alcohol-free mouthwash solution intrinsically contaminated with B. cepacia was the source of these colonizations and infections involving adults in the ICU.

Indigenous beers (chicha) are part of the indigenous culture in Ecuador. The fermentation process of these beers probably relies on microorganisms from fermented substrates, environment and human microbiota. We analyzed the microbiota of artisanal beers (including a type of beer produced after chewing boiled cassava) using bacterial culture and 16S ribosomal RNA (rRNA) gene-based tag-encoded FLX amplicon pyrosequencing (bTEFAP). Surprisingly, we found thatStreptococcus salivariusandStreptococcus mutans(part of the human oral microbiota) were among the most abundant bacteria in chewed cassava and in non-chewed cassava beers. We also demonstrated thatS. salivariusandS. mutans(isolated from these beers) could proliferate in cassava mush.Lactobacillussp. was predominantly present in most types of Ecuadorianchicha.

Leptospires can persist for months in nutrient-poor aqueous environments prior to transmission to a mammalian host. Interactions with environmental bacteria and biofilm formation are possible mechanisms of persistence of leptospires in the environment. Bacteria isolated from rivers in the Ecuadorian rainforest were tested for their ability to support leptospiral viability. We found that co-culture with Sphingomonas spp., but not Flavobacterium spp. or Delftia spp., enabled survival of L. biflexa and L. meyeri for up to a year in distilled water. We also found that L. interrogans biofilms formed in distilled water contained viable organisms that rapidly dispersed into the planktonic phase in the presence of nutrients in serum or EMJH medium. These data inform our understanding of leptospiral survival strategies that enable long-term persistence in nutrient-poor conditions yet allow rapid mobilization when nutrients become available.

A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies ( Psathyromyia abonnenci , formerly Lutzomyia abonnenci ) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogenetic analysis of the complete coding sequence showed that EPEV represents a distinct clade which diverged from a lineage that was ancestral to the nonvectored flaviviruses Entebbe bat virus, Yokose virus, and Sokoluk virus and also the Aedes -associated mosquito-borne flaviviruses, which include yellow fever virus, Sepik virus, Saboya virus, and others. EPEV replicated in C6/36 mosquito cells, yielding high infectious titers, but failed to reproduce either in vertebrate cell lines (Vero, BHK, SW13, and XTC cells) or in suckling mouse brains. This surprising result, which appears to eliminate an association with vertebrate hosts in the life cycle of EPEV, is discussed in the context of the evolutionary origins of EPEV in the New World. IMPORTANCE The flaviviruses are rarely (if ever) vectored by sand fly species, at least in the Old World. We have identified the first representative of a sand fly-associated flavivirus, Ecuador Paraiso Escondido virus (EPEV), in the New World. EPEV constitutes a novel clade according to current knowledge of the flaviviruses. Phylogenetic analysis of the virus genome showed that EPEV roots the Aedes -associated mosquito-borne flaviviruses, including yellow fever virus. In light of this new discovery, the New World origin of EPEV is discussed together with that of the other flaviviruses.

En 20 provincias ecuatorianas, se colectaron 91 muestras de alimentos fermentados preparados de forma artesanal con el objetivo de identificar cepas con uso potencial en la producción de alimentos fermentados. Se aislaron 119 cepas que fueron caracterizadas a través de pruebas fenotípicas y secuenciamiento del ADN ribosomal 16S. Del total de cepas aisladas, 47% fueron Lactobacillus sp. heterofermentadores facultativos, 31% fueron cocos homofermentadores pertenecientes a los géneros Pediococcus, Lactococcus y Enterococcus, 11% fueron Lactobacillus sp. heterofermentadores obligados y el 11% restante cocos heterofermentadores de los géneros Weissella y Leuconostoc. Algunas cepas presentaron ciertas propiedades con posible aplicación en la industria alimentaria como actividad caseinolítica y la producción exopolisacárido y bacteriocinas.