Dominance of ST131, B2, blaCTX-M-15, and papA-papC-kpsMII-uitA among ESBL Escherichia coli isolated from bloodstream infections in Quito, Ecuador: a 10-year surveillance study (2009-2019).

AIMS: This study aimed to examine antibiotic resistance and the epidemiology of extended-spectrum ß-lactamases (ESBL)-producing Escherichia coli associated with bloodstream infections over a period of 10 years. METHODS AND RESULTS: Isolates were collected from January 2009 to December 2019 and those testing for E. coli were included. Antibiotic susceptibility was tested using the VITEK® system. Selected isolates were further characterized by amplification of marker genes (virulence traits, phylogroups, and sequence types). A total of 166 ESBL-producing E. coli were recovered. The blaCTX-M-15 allele was the most abundant. Most of the isolates were resistant to ceftriaxone, cefepime, ceftazidime, ampicillin/sulbactam, piperacillin/tazobactam, and ciprofloxacin. No resistance to carbapenems was registered. More than 80% of bacteria were classified as extraintestinal pathogenic E. coli (ExPEC), and the combination of virulence traits:papA-papC-kpsMII-uitA was the most common. Phylogroup B2 was the most prevalent, and bacteria predominantly belonged to ST131. CONCLUSIONS: There was an increase in the ExPEC ESBL-E coli in bloodstream infections and the relationship between the isolates found in these infections during these 10 years.

Mutations associated with Helicobacter pylori antimicrobial resistance in the Ecuadorian population.

AIMS: We described the presence of Helicobacter pylori (HP) and estimated the prevalence of primary and secondary resistance using molecular detection in gastric biopsies of Ecuadorian patients. METHODS AND RESULTS: 66.7% (238/357) of the patients demonstrated the presence of HP using CerTest qPCR. Of these, 69.79% (104/149) were without previous HP eradication treatment and 64.42% (134/208) with prior HP eradication treatment. The mutation-associated resistance rate for clarithromycin was 33.64% (primary resistance) and 32.82% (secondary resistance), whereas that in levofloxacin the primary and secondary resistance was 37.38% and 42%, respectively. For tetracycline and rifabutin, primary and secondary resistance was 0%. Primary and secondary resistance for metronidazole and amoxicillin could not be evaluated by genotypic methods (PCR and sequencing). CONCLUSIONS: The analysis of mutations in gyrA, 23S rRNA and 16S rRNA is useful to detect bacterial resistance as a guide for eradication therapy following failure of the first-line regimen. SIGNIFICANCE AND IMPACT OF THE STUDY: This study carried out in an Ecuadorian population indicates that the resistance of HP to first-line antibiotics is high, which may contribute to the high rates of treatment failure, and other treatment alternatives should be considered.

Current situation of endemic mycosis in the Americas and the Caribbean: Proceedings of the first international meeting on endemic mycoses of the Americas (IMEMA).

BACKGROUND: The Americas are home to biologically and clinically diverse endemic fungi, including Blastomyces, Coccidioides, Emergomyces, Histoplasma, Paracoccidioides and Sporothrix. In endemic areas with high risk of infection, these fungal pathogens represent an important public health problem. OBJECTIVES: This report aims to summarise the main findings of the regional analysis carried out on the status of the endemic mycoses of the Americas, done at the first International Meeting on Endemic Mycoses of the Americas (IMEMA). METHODS: A regional analysis for the Americas was done, the 27 territories were grouped into nine regions. A SWOT analysis was done. RESULTS: All territories reported availability of microscopy. Seventy percent of territories reported antibody testing, 67% of territories reported availability of Histoplasma antigen testing. None of the territories reported the use of (1-3)-ß-d-glucan. Fifty two percent of territories reported the availability of PCR testing in reference centres (mostly for histoplasmosis). Most of the territories reported access to medications such as trimethoprim-sulfamethoxazole, itraconazole, voriconazole and amphotericin B (AMB) deoxycholate. Many countries had limited access to liposomal formulation of AMB and newer azoles, such as posaconazole and isavuconazole. Surveillance of these fungal diseases was minimal. CONCLUSIONS: A consensus emerged among meeting participants, this group concluded that endemic mycoses are neglected diseases, and due to their severity and lack of resources, the improvement of diagnosis, treatment and surveillance is needed.

Antibiotic resistance of Salmonella strains from layer poultry farms in central Ecuador.

AIMS: This study evaluated the antimicrobial resistance of Salmonella enterica strains from layer poultry farms in central Ecuador isolated during 2017. This geographical area is responsible for around 60% of total domestic egg production, yet, as of 2019, no reports had been published on the phenotypic and genotypic antibiotic resistance patterns of Salmonella in the layer poultry farms of this area. METHODS AND RESULTS: Thirty-one isolates from layer poultry farms in central Ecuador obtained during 2017 were evaluated. The resistance profiles exhibited considerable differences in serovar and sample origin, grouping into nine clades by phenotype. S. Infantis strains were of the MDR phenotype in 94·4% of isolates. S. Typhimurium strains were of a reduced antimicrobial resistance phenotype and 50% showed resistance to one antimicrobial compound. One of the S. enterica nontyped strains had an MDR profile to 11 of the 20 antibiotics evaluated (eight groups). And the two remaining S. enterica nontyped strains showed resistance to two and three antibiotics respectively. The ESBL phenotype, which is resistant to clinically notable antibiotics such as ceftriaxone, ampicillin and cefepime, was observed only in S. Infantis (15/18). These strains harbour the emerging blaCTX-M-65 gene, and co-harbour tetA and sul1 resistance genes in four strains. Additional ß-lactamase genes, carbapenemase-producing genes (blaIMP, blaVIM , blaOXA48 , blaKPC , blaNDM ) and colistin-mobile resistance gene mcr-1 were not detected. CONCLUSIONS: The findings highlight the potential role of layer poultry farm environments in central Ecuador as reservoirs of MDR Salmonella strains. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest the necessity of reinforcing biosecurity practices to reduce the probability of transmission of MDR Salmonella across the food chain.

High quantities of multidrug-resistant Escherichia coli are present in the Machángara urban river in Quito, Ecuador.

Urban river pollution by multidrug-resistant (MDR) bacteria constitutes an important public health concern. Epidemiologically important strains of MDR Escherichia coli transmissible at the human-animal-environment interfaces are especially worrying. Quantifying and characterizing MDR E. coli at a molecular level is thus imperative for understanding its epidemiology in natural environments and its role in the spread of resistance in precise geographical areas. Cefotaxime-resistant E. coli was characterized along the watercourse of the major urban river in Quito. Our results showed high quantities of cefotaxime-resistant E. coli (2.7 × 103-5.4 × 105 CFU/100 mL). The antimicrobial resistance index (ARI) revealed the exposure of the river to antibiotic contamination, and the multiple antibiotic resistance index indicated a high risk of contamination. The blaCTX-M-15 gene was the most prevalent in our samples. Isolates also had class 1 integrons carrying aminoglycoside-modifying enzymes and folate pathway inhibitors. The isolates belonged to phylogroups A, B1 and D. Clonal complex 10 was found to be the most prevalent (ST10, ST44 and ST 167), followed by ST162, ST394 and ST46. Our study provides a warning about the high potential of the major urban river in Quito for spreading the epidemiologically important MDR E. coli.

Staphylococcus aureus bloodstream infections in Latin America: results of a multinational prospective cohort study.

BACKGROUND: Substantial heterogeneity in the epidemiology and management of Staphylococcus aureus bacteraemia (SAB) occurs in Latin America. We conducted a prospective cohort study in 24 hospitals from nine Latin American countries. OBJECTIVES: To assess the clinical impact of SAB in Latin America. PATIENTS AND METHODS: We evaluated differences in the 30 day attributable mortality among patients with SAB due to MRSA compared with MSSA involving 84 days of follow-up. Adjusted relative risks were calculated using a generalized linear model. RESULTS: A total of 1030 patients were included. MRSA accounted for 44.7% of cases with a heterogeneous geographical distribution. MRSA infection was associated with higher 30 day attributable mortality [25% (78 of 312) versus 13.2% (48 of 363), adjusted RR: 1.94, 95% CI: 1.38-2.73, P < 0.001] compared with MSSA in the multivariable analysis based on investigators' assessment, but not in a per-protocol analysis [13% (35 of 270) versus 8.1% (28 of 347), adjusted RR: 1.10, 95% CI: 0.75-1.60, P = 0.616] or in a sensitivity analysis using 30 day all-cause mortality [36% (132 of 367) versus 27.8% (123 of 442), adjusted RR: 1.09, 95% CI: 0.96-1.23, P = 0.179]. MRSA infection was not associated with increased length of hospital stay. Only 49% of MSSA bloodstream infections (BSI) received treatment with ß-lactams, but appropriate definitive treatment was not associated with lower mortality (adjusted RR: 0.93, 95% CI: 0.70-1.23, P = 0.602). CONCLUSIONS: MRSA-BSIs in Latin America are not associated with higher 30 day mortality or longer length of stay compared with MSSA. Management of MSSA-BSIs was not optimal, but appropriate definitive therapy did not appear to influence mortality.

Antimicrobial Susceptibility of Cutibacterium acnes Isolated from Ecuadorian Patients with Acne Vulgaris.

Antimicrobial resistance to Cutibacterium acnes has become a worldwide problem in the last century, but there are no previous studies on antibiotic susceptibility patterns of this bacterium in Ecuador. A total of 129 skin swabs were collected from patients with acne vulgaris (AV) attending the dermatology department of a hospital in Quito, Ecuador, from July to August 2015. The patients selected had received registered antimicrobial therapy on at least one occasion before sampling. Microbiological procedures were performed according to conventional methods. The species of isolates were identified using a mass spectrometer system (matrix-assisted laser desorption ionization time-offlight [MALDI-TOF]). Antibiotic susceptibility tests on isolated Cutibacterium were performed using an anaerobe-sensitive panel (ANO2; Thermo Fisher; TREK Diagnostic Systems Ltd., West Sussex, UK).

A Prospective Cohort Multicenter Study of Molecular Epidemiology and Phylogenomics of Staphylococcus aureus Bacteremia in Nine Latin American Countries.

Staphylococcus aureus is an important pathogen causing a spectrum of diseases ranging from mild skin and soft tissue infections to life-threatening conditions. Bloodstream infections are particularly important, and the treatment approach is complicated by the presence of methicillin-resistant S. aureus (MRSA) isolates. The emergence of new genetic lineages of MRSA has occurred in Latin America (LA) with the rise and dissemination of the community-associated USA300 Latin American variant (USA300-LV). Here, we prospectively characterized bloodstream MRSA recovered from selected hospitals in 9 Latin American countries. All isolates were typed by pulsed-field gel electrophoresis (PFGE) and subjected to antibiotic susceptibility testing. Whole-genome sequencing was performed on 96 MRSA representatives. MRSA represented 45% of all (1,185 S. aureus) isolates. The majority of MRSA isolates belonged to clonal cluster (CC) 5. In Colombia and Ecuador, most isolates (≥72%) belonged to the USA300-LV lineage (CC8). Phylogenetic reconstructions indicated that MRSA isolates from participating hospitals belonged to three major clades. Clade A grouped isolates with sequence type 5 (ST5), ST105, and ST1011 (mostly staphylococcal chromosomal cassette mec [SCCmec] I and II). Clade B included ST8, ST88, ST97, and ST72 strains (SCCmec IV, subtypes a, b, and c/E), and clade C grouped mostly Argentinian MRSA belonging to ST30. In summary, CC5 MRSA was prevalent in bloodstream infections in LA with the exception of Colombia and Ecuador, where USA300-LV is now the dominant lineage. Clonal replacement appears to be a common phenomenon, and continuous surveillance is crucial to identify changes in the molecular epidemiology of MRSA.

Parallel Epidemics of Community-Associated Methicillin-Resistant Staphylococcus aureus USA300 Infection in North and South America.

BACKGROUND: The community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemic in the United States is attributed to the spread of the USA300 clone. An epidemic of CA-MRSA closely related to USA300 has occurred in northern South America (USA300 Latin-American variant, USA300-LV). Using phylogenomic analysis, we aimed to understand the relationships between these 2 epidemics. METHODS: We sequenced the genomes of 51 MRSA clinical isolates collected between 1999 and 2012 from the United States, Colombia, Venezuela, and Ecuador. Phylogenetic analysis was used to infer the relationships and times since the divergence of the major clades. RESULTS: Phylogenetic analyses revealed 2 dominant clades that segregated by geographical region, had a putative common ancestor in 1975, and originated in 1989, in North America, and in 1985, in South America. Emergence of these parallel epidemics coincides with the independent acquisition of the arginine catabolic mobile element (ACME) in North American isolates and a novel copper and mercury resistance (COMER) mobile element in South American isolates. CONCLUSIONS: Our results reveal the existence of 2 parallel USA300 epidemics that shared a recent common ancestor. The simultaneous rapid dissemination of these 2 epidemic clades suggests the presence of shared, potentially convergent adaptations that enhance fitness and ability to spread.

Pseudomonas aeruginosa epidemic high-risk clones and their association with multidrug-resistant.

OBJECTIVE: In Ecuador, data on molecular epidemiology, as well as circulating clones, are limited. Therefore, this study aims to know the population structure of Pseudomonas aeruginosa by identifying clones in clinical samples in Quito-Ecuador. METHODS: A significant set (45) clinical P. aeruginosa isolates were selected, including multidrug and non-multidrug resistant isolates, which were assigned to sequence types (STs) and compared with their antibiotic susceptibility profile. The genetic diversity was assessed by applying the multilocus sequence typing (MLST) scheme and the genetic relationships between different STs were corroborated by phylogenetic networks. RESULTS: The MLST analysis identified 24 different STs and the most prevalent STs were ST-3750 and ST-253. The majority of the multidrug-resistance (MDR) isolates were included in ST-3750 and ST-253, also 3 singleton STs were identified as MDR isolates. The 21 different STs were found in non-multidrug resistance (non-MDR) isolates, and only 3 STs were found in more the one isolate. CONCLUSIONS: The population structure of clinical P. aeruginosa present in these isolates indicates a significant association between MDR isolates and the clonal types: all ST-3750 and ST-253 isolates were MDR. ST-3750 is a closely related strain to the clonal complex ST111 (CC111). ST-253 and ST111 are a group of successful high-risk clones widely distributed worldwide. The multiresistant isolates studied are grouped in the most prevalent STs found, and the susceptible isolates correspond mainly with singleton STs. Therefore, these high-risk clones and their association with MDR phenotypes are contributing to the spread of MDR in Quito, Ecuador.

Evaluating low and high vitamin D levels in Ecuadorian cities from 2018 to 2022: interrupted time series and a cross-sectional study.

OBJECTIVES: To identify differences in the mean vitamin D concentrations in samples obtained from a private laboratory in Quito and to explore their relationship with the pre-pandemic and pandemic periods spanning from 2018 to 2022. DESIGN: A combination of an interrupted time series design and a retrospective cross-sectional approach. SETTING AND PARTICIPANTS: The study involved 9285 participants who had their 25-hydroxyvitamin D (25(OH)D) levels tested at a well-known private laboratory in Quito, Ecuador, from 2018 to 2022. PRIMARY AND SECONDARY OUTCOME MEASURES: The 25(OH)D levels were analysed and assessed for correlations with age, and the year the measurements were taken. RESULTS: The mean 25(OH)D level was 27.53 ng/mL (± 14.11). Approximately 68.8% of participants had serum 25(OH)D levels of less than 30 ng/mL, and 0.6% showed potential harm from excess 25(OH)D, with levels over 100 ng/mL. The analysis indicated a significant monthly increase of 0.133 units in 25(OH)D levels (p=0.006). However, the period after March 2020, compared with before, saw a non-significant decrease of 1.605 units in mean 25(OH)D levels (p=0.477). CONCLUSIONS: The study's findings indicate a significant prevalence of 25(OH)D deficiency, underscoring the necessity for preventative measures. However, the increasing trend in high 25(OH)D levels is concerning, emphasising the importance of prudent vitamin D supplement prescriptions and public education against self-medication. For efficient resource allocation and targeting of those with higher risks, it may be advantageous to concentrate vitamin D testing on specific population groups.

Cefazolin high-inoculum effect in methicillin-susceptible Staphylococcus aureus from South American hospitals.

OBJECTIVES: Clinical failures with cefazolin have been described in high-inoculum infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) producing type A ß-lactamase. We investigated the prevalence of the cefazolin inoculum effect (InE) in MSSA from South American hospitals, since cefazolin is used routinely against MSSA due to concerns about the in vivo efficacy of isoxazolyl penicillins. METHODS: MSSA isolates were recovered from bloodstream (n = 296) and osteomyelitis (n = 68) infections in two different multicentre surveillance studies performed in 2001-02 and 2006-08 in South American hospitals. We determined standard-inoculum (10(5)cfu/mL) and high-inoculum (10(7) cfu/mL) cefazolin MICs. PFGE was performed on all isolates that exhibited a cefazolin InE. Multilocus sequence typing (MLST) and sequencing of part of blaZ were performed on representative isolates. RESULTS: The overall prevalence of the cefazolin InE was 36% (131 isolates). A high proportion (50%) of MSSA isolates recovered from osteomyelitis infections exhibited the InE, whereas it was observed in 33% of MSSA recovered from bloodstream infections. Interestingly, Ecuador had the highest prevalence of the InE (45%). Strikingly, 63% of MSSA isolates recovered from osteomyelitis infections in Colombia exhibited the InE. MLST revealed that MSSA isolates exhibiting the InE belonged to diverse genetic backgrounds, including ST5, ST8, ST30 and ST45, which correlated with the prevalent methicillin-resistant S. aureus clones circulating in South America. Types A (66%) and C (31%) were the most prevalent ß-lactamases. CONCLUSIONS: Our results show a high prevalence of the cefazolin InE associated with type A ß-lactamase in MSSA isolates from Colombia and Ecuador, suggesting that treatment of deep-seated infections with cefazolin in those countries may be compromised.

First Report of Antibiotic Resistance Markers cfiA and nim Among Bacteroides fragilis Group Strains in Ecuadorian Patients.

In recent years, increasing resistance of Bacteroides fragilis to several antibiotics has been reported in different countries. The aim of this study was to evaluate the antibiotic resistance profiles of Bacteroides spp. isolated from clinical samples by phenotypic and molecular methods. A total of 40 nonrepetitive isolates of the B. fragilis group were studied from 2018 to 2019. The species was identified by API 20A system. The minimum inhibitory concentrations (MICs) were determined by Sensititre anaerobe MIC plate. The presence of the nim and cfiA genes was checked by conventional PCR. The association between genes and insertion sequence (IS) was performed by whole genome sequencing. Eleven isolates were categorized as metronidazole-resistant and only 2 isolates harbored the nim gene. Five isolates were imipenem-resistant, but cfiA gene was detected in two isolates. cfiA gene was closely related to the cfiA-4 allele and associated with IS614B. The nim gene was not related to any nim gene type and was considered a new variant named nimL. IS612 was found upstream of nimL gene. In view of the scarcity of data on B. fragilis, there is a need to surveil antibiotic resistance levels and molecular mechanisms to implement better antimicrobial therapies against this important group of bacteria.

Emergence of cryptic species and clades of Meyerozyma guilliermondii species complex exhibiting limited in vitro susceptibility to antifungals in patients with candidemia.

Members of the Meyerozyma guilliermondii species complex are able to cause superficial and life-threatening systemic infections with low susceptibility to azoles and echinocandins. We tested 130 bloodstream M. guilliermondii complex isolates collected from eight Latin American medical centers over 18 years (period 1 = 2000-2008 and period 2 = 2009-2018) to investigate trends in species distribution and antifungal resistance. The isolates were identified by rDNA ITS region sequencing, and antifungal susceptibility tests were performed against fluconazole, voriconazole, anidulafungin, and amphotericin B using the CLSI microbroth method. M. guilliermondii sensu stricto (s.s.; n = 116) was the most prevalent species, followed by Meyerozyma caribbica (n = 12) and Meyerozyma carpophila (n = 2). Based on rDNA ITS identification, three clades within M. guilliermondii sensu stricto were characterized (clade 1 n = 94; clade 2 n = 19; and clade 3 n = 3). In the second period of study, we found a substantial increment in the isolation of M. caribbica (3.4% versus 13.8%; P = 0.06) and clade 2 M. guilliermondii s.s. exhibiting lower susceptibility to one or more triazoles. IMPORTANCE Yeast-invasive infections play a relevant role in human health, and there is a concern with the emergence of non-Candida pathogens causing disease worldwide. There is a lack of studies addressing the prevalence and antifungal susceptibility of different species within the M. guilliermondii complex that cause invasive infections. We evaluated 130 episodes of M. guilliermondii species complex candidemia documented in eight medical centers over 18 years. We detected the emergence of less common species within the Meyerozyma complex causing candidemia and described a new clade of M. guilliermondii with limited susceptibility to triazoles. These results support the relevance of continued global surveillance efforts to early detect, characterize, and report emergent fungal pathogens exhibiting limited susceptibility to antifungals.

E-Learning versus Face-to-Face Methodology for Learning Antimicrobial Resistance and Prescription Practice in a Tertiary Hospital of a Middle-Income Country.

Background: Antimicrobial resistance is a growing health problem worldwide. One strategy to face this problem in a reasonable way is training health personnel for the rational use of antimicrobials. There are some difficulties associated with medical staff to receiving training with E-learning education, but there is a lack of studies and insufficient evidence of the effectiveness of this method compared to face-to-face learning. Methods: An educational intervention on antimicrobial resistance (AMR) and antimicrobial prescription practice (APP) was designed and implemented using two approaches: face-to-face and E-learning among physicians of the intensive care unit (ICU) and internal medicine ward (IMW) at Eugenio Espejo Hospital in Quito. Modalities of interventions were compared to propose a strategy of continuous professional development (CPD) for all hospital staff. An interventional study was proposed using a quasi-experimental approach that included 91 physicians, of which 49 belong to the IMW and 42 to the ICU. All of them received training on AMR­half in a face-to-face mode and the other half in an asynchronous E-learning mode. They then all participated on APP training but with switched groups; those who previously participated in the face-to-face experience participated in an E-learning module and vice-versa. We evaluated self-perception about basic knowledge, attitudes and referred practices towards AMR and APP before and after the intervention. A review of medical records was conducted before and after training by checking antimicrobial prescriptions for all patients in the ICU and IMW with bacteremia, urinary tract infection (UTI), pneumonia, and skin and soft tissue infection. The study received IRB clearance, and we used SPSS for statistical analysis. Results: No statistically significant difference was observed between the E-learning and the face-to-face methodology for AMR and APP. Both methodologies improved knowledge, attitudes and referred practices. In the case of E-learning, there was a self-perception of improved attitudes (p < 0.05) and practices (p < 0.001) for both AMR and APP. In face-to-face, there was a perception of improvement only in attitudes (p < 0.001) for APP. In clinical practice, the use of antimicrobials significantly improved in all domains after training, including empirical and targeted treatment of bacteremia and pneumonia (p < 0.001) and targeted treatment of UTI (p < 0.05). For the empirical treatment of pneumonia, the mean number of antibiotics was reduced from 1.87 before to 1.05 after the intervention (p = 0.003), whereas in the targeted management of bacteremia, the number of antibiotics was reduced from 2.19 to 1.53 (p = 0.010). Conclusions: There was no statistically significant difference between the effect of E-learning and face-to-face strategy in terms of teaching AMR and APP. Adequate self-reported attitudes and practices in E-learning exceed those of the face-to-face approach. The empiric and targeted use of antimicrobials improved in all reviewed cases, and we observed an overall decrease in antibiotic use. Satisfaction with training was high for both methods, and participants valued the flexibility and accessibility of E-learning.

High Prevalence of Prototheca bovis Infection in Dairy Cattle with Chronic Mastitis in Ecuador.

The genus Prototheca, a unicellular, non-photosynthetic, yeast-like microalgae, is a pathogen of concern for the dairy industry. It causes bovine mastitis that currently cannot be cured, and hence generates significant economic losses in milk production. In this study, for the first time in Ecuador, we identify Prototheca bovis as the etiologic agent of chronic mastitis in dairy cattle. Milk samples (n = 458) of cows with chronic mastitis were cultured on Sabouraud Dextrose Agar (SDA). Microscopy and cytB gene sequencing were used to identify Prototheca, whereby Prototheca bovis was isolated from 15.1% (n = 69) of the milk samples, one of the highest infection rates that can be found in the literature in a "non-outbreak" situation. No other Prototheca species were found. We were unable to isolate the alga from environmental samples. We showed that P. bovis was relatively resistant to disinfectants used to sterilize milking equipment on the cattle farms where it was isolated. We discuss how to avoid future infection and also hypothesize that the real prevalence of Prototheca infection in bovine mastitis is probably much higher than what was detected. We recommend a protocol to increase the diagnostic yield in the bacteriology laboratory.

Antimicrobial stewardship programs in adult intensive care units in Latin America: Implementation, assessments, and impact on outcomes.

OBJECTIVE: To assess the impact of antimicrobial stewardship programs (ASPs) in adult medical-surgical intensive care units (MS-ICUs) in Latin America. DESIGN: Quasi-experimental prospective with continuous time series. SETTING: The study included 77 MS-ICUs in 9 Latin American countries. PATIENTS: Adult patients admitted to an MS-ICU for at least 24 hours were included in the study. METHODS: This multicenter study was conducted over 12 months. To evaluate the ASPs, representatives from all MS-ICUs performed a self-assessment survey (0-100 scale) at the beginning and end of the study. The impact of each ASP was evaluated monthly using the following measures: antimicrobial consumption, appropriateness of antimicrobial treatments, crude mortality, and multidrug-resistant microorganisms in healthcare-associated infections (MDRO-HAIs). Using final stewardship program quality self-assessment scores, MS-ICUs were stratified and compared among 3 groups: ≤25th percentile, >25th to <75th percentile, and ≥75th percentile. RESULTS: In total, 77 MS-ICU from 9 Latin American countries completed the study. Twenty MS-ICUs reached at least the 75th percentile at the end of the study in comparison with the same number who remain within the 25th percentile (score, 76.1 ± 7.5 vs 28.0 ± 7.3; P < .0001). Several indicators performed better in the MS-ICUs in the 75th versus 25th percentiles: antimicrobial consumption (143.4 vs 159.4 DDD per 100 patient days; P < .0001), adherence to clinical guidelines (92.5% vs 59.3%; P < .0001), validation of prescription by pharmacist (72.0% vs 58.0%; P < .0001), crude mortality (15.9% vs 17.7%; P < .0001), and MDRO-HAIs (9.45 vs 10.96 cases per 1,000 patient days; P = .004). CONCLUSION: MS-ICUs with more comprehensive ASPs showed significant improvement in antimicrobial utilization.

Evidence of SARS-CoV-2 reinfection within the same clade in Ecuador: A case study.

OBJECTIVES: To date, reported SARS-CoV-2 reinfection cases are mainly from strains belonging to different clades. As the pandemic advances, a few lineages have become dominant in certain areas leading to reinfections by similar strains. Here, we report a reinfection case within the same clade of the initial infection in a symptomatic 28-year-old-male in Quito-Ecuador. METHODS: Infection was detected by reverse transcription-polymerase chain reaction, and immune response evaluated by antibody testing. Whole-genome sequencing was performed and phylogenetic analysis conducted to determine relatedness. RESULTS: Both the infection and the reinfection strains were assigned as Nextstrain 20B, Pangolin lineage B.1.1 and GISAID clade O. Our analysis indicated 4-6 fold more nucleotide changes than are expected for reactivation or persistence compared with the natural rate of SARS-CoV-2 mutation (∼2-3 nucleotide changes per month), thus supporting reinfection. Furthermore, approximately 3 months after the second infection, COVID-19 antibodies were not detectable in the patient, suggesting potential vulnerability to a third infection. CONCLUSIONS: Our results showed evidence of SARS-CoV-2 reinfection within the same clade in Ecuador, indicating that previous exposure to SARS-CoV-2 does not guarantee immunity in all cases.

Pneumococcal Carriage Among Indigenous Kichwa Children From the Ecuadorian Andes After the 10-Valent Pneumococcal Vaccine Introduction.

BACKGROUND: We assessed nasopharyngeal pneumococcal carriage in Andean Kichwa children, the largest Amerindian indigenous population in the Ecuadorian Andes. All children in our study had been vaccinated with the 10-valent pneumococcal vaccine (PCV10). METHODS: Nasopharyngeal swabs from 63 families, 100 children <10 years old including 38 children under 5 years and 63 adult caregivers, from 5 different communities, were cultivated for Streptococcus pneumoniae and isolates were serotyped and antibiotic susceptibility testing was performed. RESULTS: Respectively, 67% of the 38 children under 5 years old, 49% of the 62 children between 6 and 10 years old and 16% of the 100 adults were colonized with S. pneumoniae. Of these, 30.9% carried a vaccine serotype, 5.4% a serotype shared by the PCV10/13-valent pneumococcal vaccine (PCV13) vaccine and 25.5% a PCV13 serotype or PCV13 vaccine-related serotype, with 19A (10.9%) and 6C (10.9%) as the most prominent. Drug susceptibility testing revealed that 46% of the S. pneumoniae strains were susceptible to 6 tested antibiotics. However, 20.3% of the strains were multidrug-resistant or extensively drug-resistant strains, including 82% of the vaccine (-related) serotype 19A and 6C strains. CONCLUSIONS: Kichwa children, vaccinated with PCV10, were highly colonized with pneumococci and should be considered a high-risk group for pneumococcal disease. Twenty-five percent of the colonizing S. pneumoniae strains were PCV13-only vaccine-targeted serotypes, and in addition to that, most were multidrug-resistant or extensively drug-resistant strains. The vaccine benefits for this population possibly will significantly increase with the introduction of PCV13.