RESUMEN

BACKGROUND: Zoonotic sporotrichosis caused by Sporothrix brasiliensis has become the main subcutaneous mycosis in Brazil. Minas Gerais (MG) is located in southeast Brazil and since 2015 has experienced an epidemic of zoonotic sporotrichosis. OBJECTIVES: This study aimed to reconstruct the epidemiological scenario of sporotrichosis from S. brasiliensis in recent epizooty in the Metropolitan Region of Belo Horizonte (MRBH), MG. METHODS: A total of 95 Sporothrix spp. isolates (Sporothirx brasiliensis n = 74, S. schenckii n = 11 and S. globosa n = 10) were subjected to Amplified Fragment Length Polymorphism (AFLP) genotyping and mating-type analysis to determine genetic diversity and population structure. Of these, 46 S. brasiliensis isolates were recovered from animals (cats n = 41 and dogs n = 5) from MRBH. RESULTS: Our study describes the high interspecific differentiation power of AFLP-based genotyping between the main phylogenetic Sporothrix groups. S. brasiliensis presents high genetic variability and pronounced population structure with geographically focused outbreaks in Brazil. The genetic groups include older genotypes from the prolonged epidemic in Southeast (Rio de Janeiro and São Paulo), South (Rio Grande do Sul), Northeast (Pernambuco) and new genotypes from the MRBH. Furthermore, we provide evidence of heterothallism mating strategy in pathogenic Sporothrix species. Genotypes originating in Rio de Janeiro and Pernambuco carry the predominant MAT1-2 idiomorph as opposed to genotypes from Rio Grande do Sul, which have the MAT1-1 idiomorph. We observed an overwhelming occurrence of MAT1-1 among MRBH isolates. CONCLUSION: Our study provides clear evidence of the predominance of a genetic group profile circulating in animals in Minas Gerais, independent of that disseminated from Rio de Janeiro. Our data can help us understand the genetic population processes that drive the evolution of this fungus in Minas Gerais and contribute to future mitigation actions for this ongoing epidemic.

Asunto(s)

Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Enfermedades de los Gatos , Epidemias , Variación Genética , Genotipo , Sporothrix , Esporotricosis , Esporotricosis/epidemiología , Esporotricosis/microbiología , Brasil/epidemiología , Sporothrix/genética , Sporothrix/clasificación , Sporothrix/aislamiento & purificación , Animales , Gatos , Perros , Enfermedades de los Gatos/microbiología , Enfermedades de los Gatos/epidemiología , Zoonosis/epidemiología , Zoonosis/microbiología , Filogenia , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/microbiología , Humanos

RESUMEN

Tuberculosis (TB) is one of the three leading causes of death from a single infectious agent, Mycobacterium tuberculosis (MTB), together with COVID-19 and HIV/AIDS. This disease places a heavy burden on countries with low socio-economic development and aggravates existing inequalities. For the year 2021, estimations for Ecuador were 8500 TB cases, of which 370 were associated to multiple drug resistance (TB-MDR), and 1160 deaths. In the same year, Ecuador notified 5973 total cases, 401 of them were TB-MDR, pointing out an under diagnosis problem. The few molecular epidemiology studies available conclude that L4 is the most prevalent MTB lineage in Ecuador (with LAM as the main L4 sublineage), but L2-Beijing family is also present at low prevalence. Nevertheless, with less than 1 % MTB isolates genetically characterized by either MIRU-VNTR, spolygotyping or WGS to date, molecular epidemiology research must me improved to assist the TB surveillance and control program in Ecuador.

RESUMEN

French Guiana experienced an unprecedented dengue epidemic during 2023-2024. Prior to the 2023-2024 outbreak in French Guiana, DENV-3 had not circulated in an epidemic manner since 2005. We therefore studied retrospectively the strains circulating in the French Territories of the Americas (FTA)-French Guiana, Guadeloupe, and Martinique-from the 2000s to the current epidemic. To this end, DENV-3 samples from the collection of the National Reference Center for Arboviruses in French Guiana (NRCA-FG) were selected and sequenced using next-generation sequencing (NGS) based on Oxford Nanopore Technologies, ONT. Phylogenetic analysis showed that (i) the 97 FTA sequences obtained all belonged to genotype III (GIII); (ii) between the 2000s and 2013, the regional circulation of the GIII American-I lineage was the source of the FTA cases through local extinctions and re-introductions; (iii) multiple introductions of lineages of Asian origin appear to be the source of the 2019-2021 epidemic in Martinique and the 2023-2024 epidemic in French Guiana. Genomic surveillance is a key factor in identifying circulating DENV genotypes, monitoring strain evolution, and identifying import events.

Asunto(s)

Virus del Dengue , Dengue , Brotes de Enfermedades , Genotipo , Filogenia , Guyana Francesa/epidemiología , Humanos , Estudios Retrospectivos , Virus del Dengue/genética , Virus del Dengue/clasificación , Virus del Dengue/aislamiento & purificación , Dengue/epidemiología , Dengue/virología , Guadalupe/epidemiología , Martinica/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento , ARN Viral/genética

RESUMEN

This study aims to characterize the molecular profile of the hepatitis B virus (HBV) among socially vulnerable immigrants residing in Brazil to investigate the introduction of uncommon HBV strains into the country. Serum samples from 102 immigrants with positive serology for the HBV core antibody (anti-HBc) were tested for the presence of HBV DNA by PCR assays. Among these, 24 were also positive for the HBV surface antigen (HBsAg). The full or partial genome was sequenced to determine genotype by phylogenetic analysis. Participants were from Haiti (79.4%), Guinea-Bissau (11.8%), Venezuela (7.8%), and Colombia (1%). Of the 21 HBV DNA-positive samples, subgenotypes A1 (52.4%), A5 (28.6%), E (9.5%), F2 (4.8%), and F3 (4.8%) were identified. Among the 78 HBsAg-negative participants, four were positive for HBV DNA, resulting in an occult HBV infection rate of 5.1%. Phylogenetic analysis suggested that most strains were likely introduced to Brazil by migration. Importantly, 80% of A5 sequences had the A1762T/G1764A double mutation, linked to an increased risk of hepatocellular carcinoma development. In conclusion, this study is the first report of HBV subgenotype A5 in Brazil, shedding new light on the diversity of HBV strains circulating in the country. Understanding the genetic diversity of HBV in immigrant communities can lead to better prevention and control strategies, benefiting both immigrants and wider society.

Asunto(s)

Carcinoma Hepatocelular , Emigrantes e Inmigrantes , Genotipo , Virus de la Hepatitis B , Hepatitis B , Neoplasias Hepáticas , Mutación , Filogenia , Humanos , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Brasil/epidemiología , Neoplasias Hepáticas/virología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/epidemiología , Carcinoma Hepatocelular/virología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/epidemiología , Femenino , Masculino , Adulto , Hepatitis B/virología , Hepatitis B/epidemiología , Hepatitis B/genética , Persona de Mediana Edad , ADN Viral/genética , Antígenos de Superficie de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/sangre , África/etnología , África/epidemiología , América Latina/etnología , América Latina/epidemiología

RESUMEN

INTRODUCTION: Dengue disease represents a large and growing global threat to public health, accounting for a significant burden to health systems of endemic countries. The World Health Organization's (WHO) Strategic Advisory Group of Experts (SAGE) and the European Medicines Agency (EMA) currently recommend the use of TAK-003 dengue vaccine in high dengue burden and transmission settings for countries considering vaccination as part of their integrated management strategy for prevention and control of Dengue. AREAS COVERED: This paper describes the main conclusions of a workshop held by the Arbovirus Committee of the Latin American Society of Pediatric Infectious Diseases (SLIPE) in November 2023, to generate consensus recommendations on the introduction of this new vaccine in the region. Considerations were made regarding the molecular epidemiology of dengue infection in the Americas and the need for more precise phylogenetic classification and correlation with clinical outcome and disease severity. EXPERT OPINION: Introduction of dengue vaccine should be considered as an strategy for health entities in the region, with participation of social sectors, scientific societies, and ministries of health that could be able to create a successful vaccination program.

Asunto(s)

Vacunas contra el Dengue , Dengue , Epidemiología Molecular , Humanos , Vacunas contra el Dengue/inmunología , Vacunas contra el Dengue/administración & dosificación , Dengue/prevención & control , Dengue/epidemiología , América Latina/epidemiología , Virus del Dengue/inmunología , Virus del Dengue/genética , Vacunación/métodos , Filogenia , Organización Mundial de la Salud , Programas de Inmunización

RESUMEN

The COVID-19 pandemic has been marked by novel viral variants, posing challenges to global public health. Recombination, a viral evolution mechanism, is implicated in SARS-CoV-2's ongoing evolution. The XBB recombinant lineage, known for evading antibody-mediated immunity, exhibits higher transmissibility without increased disease severity. We investigated the prevalence and genomic features of XBB in SARS-CoV-2-positive cases in Rio Grande do Sul (RS), Brazil. We sequenced 357 samples from epidemiological weeks (EW) 47/2022 to 17/2023, and included 389 publicly available sequences. Clinical and epidemiological data were obtained from DATASUS, e-SUS, and SIVEP GRIPE (data recording systems of the Brazilian Ministry of Health). Of these, 143 were classified as XBB and 586 were other Omicron lineages. In March 2023 (EW 10), XBB became dominant, accounting for 83.3% of cases. 97.7% of XBB-infected patients successfully recovered from the infection, with a low mortality rate (2.3%). Even after receiving three vaccine doses and having been previously infected, 59.5% of the patients experienced reinfection with XBB. However, for 54% of the individuals, the interval between their XBB infection and the last vaccine dose exceeded one year, potentially leading to a decline in antibody levels. In addition, we identified 90 mutations in RS circulating XBB, spread throughout the genome, notably in the Spike protein region associated with immune resistance. This study provides insights into the dynamics and impact of a recombinant variant becoming predominant for the first time in the state. Continued surveillance of SARS-CoV-2 genomic evolution is crucial for effective public health management.

Asunto(s)

Vacunas contra la COVID-19 , COVID-19 , Genoma Viral , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Brasil/epidemiología , COVID-19/epidemiología , COVID-19/inmunología , COVID-19/virología , COVID-19/prevención & control , Vacunas contra la COVID-19/inmunología , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Filogenia , Adulto Joven , Adolescente , Genómica/métodos

RESUMEN

Group B Streptococcus sequence type 103 is known primarily as a bovine mastitis pathogen. In Brazil, it has circulated in cattle and humans since the 1990s. It lacks scpB and, in humans, was found only among carriage isolates. Bovine-human interspecies transmission may have contributed to its evolution and spread.

Asunto(s)

Infecciones Estreptocócicas , Bovinos , Humanos , Brasil/epidemiología , Animales , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/transmisión , Streptococcus agalactiae/genética , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/aislamiento & purificación , Femenino , Mastitis Bovina/microbiología , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/epidemiología , Filogenia

RESUMEN

INTRODUCTION: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a serious threat to public health. Globally, carbapenemases-producing CRPA isolates mainly belong to 'high-risk' clones; however, the molecular epidemiology of CRPA isolates circulating in Chile are scarce, where this pathogen is the main aetiological agent of ventilator-associated pneumonia. OBJECTIVES: To characterize the phylogenomics and molecular features of ST654 CRPA isolates collected in Chile between 2016 and 2022. METHODS: Eighty-nine CRPA isolates collected in different Chilean hospitals from clinical specimens between 2005 and 2022 were analysed. Antibiotic susceptibility tests and carbapenemases production were carried out on the CRPA ST654 isolates. Also, they were subjected to whole-genome sequencing, from which in silico analyses were performed. RESULTS: Thirty-four strains (38.2%) belonged to the ST654 high-risk clone, being the most predominant lineage of the collection. Most of these isolates belonged to a subclade including KPC producers that also clustered with strains from Argentina and the United States, whereas few VIM and NDM co-producers clustered in two different smaller subclades. The isolates exhibited a broad resistome encompassing genes mediating resistance to several other clinically relevant drugs. Additionally, all the 34 ST654 isolates were ExoS+ as a virulence factor and associated to the O4-serotype. CONCLUSIONS: Our report represents the most comprehensive phylogenomic study of a CRPA high-risk clone ST654 to date. Our analyses suggest that this lineage is undergoing a divergent evolutionary path in Chile, because most of the isolates were KPC producers and were O4 serotype, differing from previous descriptions, which underline the relevance of performing molecular surveillance on this pathogen.

Asunto(s)

Proteínas Bacterianas , Carbapenémicos , Pruebas de Sensibilidad Microbiana , Filogenia , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Secuenciación Completa del Genoma , beta-Lactamasas , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/aislamiento & purificación , Pseudomonas aeruginosa/clasificación , Chile/epidemiología , Humanos , Carbapenémicos/farmacología , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/epidemiología , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Hospitales , Antibacterianos/farmacología , Epidemiología Molecular , Genoma Bacteriano , Femenino , Masculino , Persona de Mediana Edad , Neumonía Asociada al Ventilador/microbiología , Neumonía Asociada al Ventilador/epidemiología , Genómica , Anciano , Adulto , Farmacorresistencia Bacteriana Múltiple/genética

RESUMEN

BACKGROUND: The high levels of recent transmission of leprosy worldwide demonstrate the necessity of epidemiologic surveillance to understand and control its dissemination. Brazil remains the second in number of cases around the world, indicating active transmission of Mycobacterium leprae (M. leprae) in the population. At this moment, there is a consensus that the bacillus is transmitted by inter-human contact, however, different serologic, molecular, and histopathological approaches indicate the existence of non-human transmission sources. METHODS AND RESULTS: The qPCR assay was used to amplify the molecular targets 16S RNAr and RLEP, in samples of liver, spleen, and ear of wild animals belonging to Didelphimorphia and Rodentia orders, in highly endemic areas of Mato Grosso, Brazil. The RLEP repetitive sequence was positive in 202 (89.0%) samples, with 96 (42.3%) of these also being positive for the 16S gene. Regarding the collection sites, it was observed that the animals were found in areas profoundly deforested, close to urban areas. CONCLUSIONS: Our results suggest that wild animals can play an important role in the maintenance of M. leprae in endemic regions with major anthropic action in Brazil. Therefore, integrating human, animal, and environmental health care with the One Health initiative is highly efficient for the development of effective strategies to contain and control leprosy in Brazil.

Asunto(s)

Lepra , Mycobacterium leprae , Roedores , Mycobacterium leprae/genética , Mycobacterium leprae/aislamiento & purificación , Brasil/epidemiología , Animales , Roedores/microbiología , Lepra/epidemiología , Lepra/veterinaria , Lepra/microbiología , Lepra/transmisión , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/microbiología , Humanos , Animales Salvajes/microbiología , ARN Ribosómico 16S/genética

RESUMEN

Ovine gammaherpesvirus 2 (OvGHV2), is a Macavirus and the cause of sheep-associated malignant catarrhal fever (SA-MCF), in which sheep are the asymptomatic reservoir hosts. Susceptible mammalian populations infected by OvGHV2 may develop clinical SA-MCF or subclinical infections. All members of the Macavirus genus known to be associated with MCF are collectively referred to as the MCF virus (MCFV) complex. This report describes the occurrence of subclinical OvGHV2-related infections in free-ranging wild boars (Sus scrofa) from southern Brazil. Specific body organs (n = 14) and biological samples (nasal and oral swabs; n = 17) were collected from 24 asymptomatic wild boars from a conservation unit located within the Central-eastern mesoregion of Paraná State. Organs were processed to observe histopathological patterns suggestive of diseases of domestic animals; only pulmonary samples were used in an immunohistochemical assay designed to detect MCFV tissue antigens. Furthermore, all samples were submitted to molecular assays designed to detect the OvGHV2 tegument protein gene. Viral-induced pneumonia was diagnosed in two wild boars; one of these contained OvGHV2 DNA, with MCFV antigens identified in the other. Additionally, MCFV tissue antigens were detected within pulmonary epithelial cells of the lungs with and without pulmonary disease. Collectively, OvGHV2 was detected in 37.5% (9/24) of all wild boars, with detection occurring in the organs of 57.1% (8/14) wild boars and the oral cavity of one animal. These results demonstrated that these wild boars were subclinically infected by OvGHV2, and that infection produced typical pulmonary alterations. In addition, the detection of OvGHV2 within the oral cavity of one wild boar may suggest that this animal may be a potential disseminator of this pathogen to susceptible animal populations, including livestock and wildlife, acting as a possible bridge host for OvGHV2. Furthermore, infection by OvGHV2 probably occurred due to incidental contact with asymptomatic sheep maintained within the surrounding rural areas and not within the conservation units.

RESUMEN

Sheep respiratory disease (SRD) is a multifactorial illness commonly affecting sheep. Mesomycoplasma (Mycoplasma) ovipneumoniae is one of the most important etiological agents of SRD and should be better understood, especially in countries where it was recently detected, such as Brazil. Also, the intensive use of quinolones in mycoplasmal infections increases the selective pressure for resistance to this drug class, and no data about antimicrobial resistance in Brazil is available. Therefore, this study aimed to perform a comparative genomic analysis of newly isolated Brazilian M. ovipneumoniae strains, identify point mutations in target genes that may be associated with antibiotic resistance, and perform a phylogenomic analysis of these strains with available genome representatives of M. ovipneumoniae. Glucose-fermenting fried egg-like colonies identified as M. ovipneumoniae were obtained after a culture of tracheobronchial lavage from infected sheep. The genomes were sequenced, de novo assembled and comparatively evaluated. Important putative virulence factors were detected in all isolates: the analysis of the average nucleotide homology of all these genes with the M. ovipneumoniae ATCC 29419 revealed associations between clpB, lgt, tuf, and dnaJ genes and geographic location. In addition, nucleotide substitutions in a few positions of the Quinolone-Resistant Determinant Region of the gyrA gene, including the Ser83Ala, were detected. The phylogenomic analysis showed that the Brazilian isolates belonged to two different clades corresponding to geographic location, and the isolates from São Paulo showed high similarity, which differs from isolates from Rio de Janeiro. This first genomic analysis of the Brazilian M. ovipneumoniae genomes demonstrates strain segregation according to location and health status, reinforcing the importance of continuous surveillance and diagnostics of this bacteria causing sheep respiratory disease in the Brazilian flocks.

Asunto(s)

Girasa de ADN , Genoma Bacteriano , Mycoplasma ovipneumoniae , Filogenia , Enfermedades de las Ovejas , Brasil/epidemiología , Animales , Ovinos , Enfermedades de las Ovejas/microbiología , Enfermedades de las Ovejas/epidemiología , Girasa de ADN/genética , Mycoplasma ovipneumoniae/genética , Mutación , Antibacterianos/farmacología , Genómica , Factores de Virulencia/genética , Farmacorresistencia Bacteriana/genética , Neumonía por Mycoplasma/microbiología , Neumonía por Mycoplasma/veterinaria , Neumonía por Mycoplasma/epidemiología

RESUMEN

The causative agent of Chagas disease is Trypanosoma cruzi, which is widely distributed throughout the South American continent and extends into North America. Its occurrence in bats is poorly described and may impact the disease's maintenance and epidemiology. The aim of this study was to detect the agent by PCR assays targeting kDNA and nuclear DNA in the organs of 203 urban bats and rural vampire bats from the Brazilian Atlantic Forest, São Paulo state, during the pandemic period from 2020 to 2022. In total, 6 of the 203 bats (2.97%) were positive for T. cruzi. Infection was detected in 2% (2/101) of Desmodus rotundus, 33% (1/3) of Nyctinomops laticaudatus, 25% (1/4) of Artibeus lituratus, 4% (1/24) of Eumops glaucinus and in 2% (1/41) of Molossus molossus. The gene sequences obtained were assessed for quality and deposited in a public repository. Fruit bats were statistically associated with positivity for T. cruzi. To our knowledge, this study detected T. cruzi for the first time in bats from São Paulo state and in N. laticaudatus and E. glaucinus species.

RESUMEN

Salmonella enterica serovar Infantis (S. Infantis) is a globally distributed non-typhoid serovar infecting humans and food-producing animals. Considering the zoonotic potential and public health importance of this serovar, strategies to characterizing, monitor and control this pathogen are of great importance. This study aimed to determine the genetic relatedness of 80 Brazilian S. Infantis genomes in comparison to 40 non-Brazilian genomes from 14 countries using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and CRISPR-Multi-Locus Virulence Sequence Typing (CRISPR-MVLST). CRISPR spacers were searched using CRISPR-Cas++ and fimH and sseL alleles using BLAST and MEGA X. Results were analyzed using BioNumerics 7.6 in order to obtain similarity dendrograms. A total of 23 CRISPR1 and 11 CRISPR2 alleles formed by 37 and 26 types of spacers, respectively, were detected. MVLST revealed the presence of five fimH and three sseL alleles. CRISPR's similarity dendrogram showed 32 strain subtypes, with an overall similarity ≥ 78.6. The CRISPR-MVLST similarity dendrogram showed 37 subtypes, with an overall similarity ≥ 79.2. In conclusion, S. Infantis strains isolated from diverse sources in Brazil and other countries presented a high genetic similarity according to CRISPR and CRISPR-MVLST, regardless of their source, year, and/or place of isolation. These results suggest that both methods might be useful for molecular typing S. Infantis strains using WGS data.

Asunto(s)

Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Genoma Bacteriano , Salmonella enterica , Brasil , Salmonella enterica/genética , Salmonella enterica/clasificación , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Genoma Bacteriano/genética , Humanos , Filogenia , Tipificación de Secuencias Multilocus , Animales , Sistemas CRISPR-Cas/genética , Serogrupo

RESUMEN

Group B Streptococcus (GBS) is a major cause of contagious bovine mastitis (CBM) in Brazil. The GBS population is composed of host-generalist and host-specialist lineages, which may differ in antimicrobial resistance (AMR) and zoonotic potential, and the surveillance of bovine GBS is crucial to developing effective CBM control and prevention measures. Here, we investigated bovine GBS isolates (n = 156) collected in Brazil between 1987 and 2021 using phenotypic testing and whole-genome sequencing to uncover the molecular epidemiology of bovine GBS. Clonal complex (CC) 61/67 was the predominant clade in the 20th century; however, it was replaced by CC91, with which it shares a most common recent ancestor, in the 21st century, despite the higher prevalence of AMR in CC61/67 than in CC91, and high selection pressure for AMR from indiscriminate antimicrobial use in the Brazilian dairy industry. CC103 also emerged as a dominant CC in the 21st century, and a considerable proportion of herds had two or more GBS strains, suggesting poor biosecurity and within-herd evolution due to the chronic nature of CBM problems. The majority of bovine GBS belonged to serotype Ia or III, which was strongly correlated with CCs. Ninety-three isolates were resistant to tetracycline (≥8 µg/mL; tetO = 57, tetM = 34 or both = 2) and forty-four were resistant to erythromycin (2.0 to >4 µg/mL; ermA = 1, ermB = 38, mechanism unidentified n = 5). Only three isolates were non-susceptible to penicillin (≥8.0 µg/mL), providing opportunities for improved antimicrobial stewardship through the use of narrow-spectrum antimicrobials for the treatment of dairy cattle. The common bovine GBS clades detected in this study have rarely been reported in humans, suggesting limited risk of interspecies transmission of GBS in Brazil. This study provides new data to support improvements to CBM and AMR control, bovine GBS vaccine design, and the management of public health risks posed by bovine GBS in Brazil.

RESUMEN

The emergence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections at the end of the 20th century represents a significant shift in the epidemiology of staphylococcal infections and, consequently, their clinical management. There are diverse CA-MRSA clones that are widely spread worldwide, showing differences in their regional dissemination, which has been dynamically changing over time. Although the first CA-MRSA description occurred about 30 years ago, its epidemiology in certain regions, such as South America, has been poorly explored, resulting in a gap in the understanding of the epidemiology of CA-MRSA in under-represented countries/regions. This report describes the first four clinical cases of invasive infections caused by CA-MRSA in a tertiary hospital in the central-southern region of Chile. It also associates the clinical characteristics of the infections with the microbiological and molecular features of the isolates. The four S. aureus isolates belong to sequence type 8, which has been widely described as a cause of community-acquired infections. All of them presented a wide resistome and virulome. Additionally, in two of them, it was possible to reconstruct the COMER genetic element, present in the USA300-Latin American variant clone. Considering these findings, it is crucial to prepare for a potential increase in invasive CA-MRSA infections in Chile. This would involve enhancing current surveillance systems and maintaining a low threshold of suspicion for these infections among clinicians.

RESUMEN

Chikungunya virus (CHIKV) has emerged as a significant public health concern due to its rapid spread and potential for causing debilitating epidemics. In Argentina, the virus has garnered attention since its introduction to the Americas in 2013, due to its growing incidence and impact in neighbouring countries. Here we present a comprehensive analysis of the spatiotemporal dynamics of CHIKV in Argentina, focusing on the evolutionary trajectory of its genetic variants. Through a combination of active surveillance, screening of historical and recent samples, and whole-genome sequencing, we traced the evolutionary history of CHIKV lineages circulating within the country. Our results reveal that two distinct genotypes circulated in Argentina: The Asian lineage during the 2016 epidemic and the ECSA lineage in 2023. This distribution reflects the dominance of particular variants across Latin America. Since 2023, the ECSA lineage has led to a surge in cases throughout the Americas, marking a significant shift. The replacement of lineages in the American region constitutes a major epidemiological event, potentially affecting the dynamics of virus transmission and the clinical outcomes in impacted populations. The spatiotemporal analysis highlights CHIKV's distribution across Argentina and underscores the significant role of human mobility, especially when considering recent epidemics in neighbouring countries such as Paraguay and Uruguay, which have facilitated the spread and introduction of the viral strain into different districts. By integrating epidemiological data with genomic insights, we elucidate the patterns of virus dissemination, highlighting key areas of transmission and potential factors contributing to its spread.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Evolución Molecular , Genotipo , Filogenia , Argentina/epidemiología , Virus Chikungunya/genética , Virus Chikungunya/clasificación , Virus Chikungunya/aislamiento & purificación , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Fiebre Chikungunya/transmisión , Humanos , Genoma Viral , América Latina/epidemiología , Secuenciación Completa del Genoma , Análisis Espacio-Temporal , Variación Genética

RESUMEN

We aimed to describe the landscape, including molecular, epidemiological, and clinical aspects of CHIKV infections in the Ribeirao Preto region, an area endemic to dengue. We randomly screened 3744 plasma samples that had undergone DENV diagnosis to evaluate CHIKV-RNA using an in-house RT-PCR assay. Positive samples were followed clinically, and RNA samples were submitted to whole genome sequencing. Seventeen cases (0.5 %) were positive for CHIKV-RNA despite being negative for DENV-RNA. Notably, half of the patients experienced prolonged arthralgia lasting more than 90 days. Compared with the healthy control group, leukopenia and thrombocytopenia were observed in all CHIKV-positive individuals with statistically significant P values (P < 0.0001 and P = 0.0003, respectively). The genomic analysis revealed that the CHIKV strains being studied are classified within the East-Central-South-African (ECSA) genotype. This analysis identified new mutations, E1: K211E and E2: V264A, while the previously known mutation E1: A226V was not detected among these strains. This study highlights the need for epidemiological surveillance and preparedness for potential CHIKV epidemics in Brazil, particularly where other arboviruses co-circulate.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Dengue , Genotipo , ARN Viral , Humanos , Brasil/epidemiología , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/sangre , Fiebre Chikungunya/virología , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación , Dengue/epidemiología , Dengue/virología , Masculino , Femenino , Adulto , Persona de Mediana Edad , ARN Viral/genética , Adulto Joven , Enfermedades Endémicas , Adolescente , Secuenciación Completa del Genoma , Anciano , Niño , Filogenia , Mutación , Preescolar , Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Virus del Dengue/clasificación , Trombocitopenia/epidemiología , Trombocitopenia/virología

RESUMEN

Foot-and-mouth disease is a highly contagious disease affecting cloven-hoofed animals, resulting in considerable economic losses. Its causal agent is foot-and-mouth disease virus (FMDV), a picornavirus. Due to its error-prone replication and rapid evolution, the transmission and evolutionary dynamics of FMDV can be studied using genomic epidemiological approaches. To analyze FMDV evolution and identify possible transmission routes in an Argentinean region, field samples that tested positive for FMDV by PCR were obtained from 21 farms located in the Mar Chiquita district. Whole FMDV genome sequences were obtained by PCR amplification in seven fragments and sequencing using the Sanger technique. The genome sequences obtained from these samples were then analyzed using phylogenetic, phylogeographic, and evolutionary approaches. Three local transmission clusters were detected among the sampled viruses. The dataset was analyzed using Bayesian phylodynamic methods with appropriate coalescent and relaxed molecular clock models. The estimated mean viral evolutionary rate was 1.17 × 10- 2 substitutions/site/year. No significant differences in the rate of viral evolution were observed between farms with vaccinated animals and those with unvaccinated animals. The most recent common ancestor of the sampled sequences was dated to approximately one month before the first reported case in the outbreak. Virus transmission started in the south of the district and later dispersed to the west, and finally arrived in the east. Different transmission routes among the studied herds, such as non-replicating vectors and close contact contagion (i.e., aerosols), may be responsible for viral spread.

Asunto(s)

Virus de la Fiebre Aftosa , Picornaviridae , Animales , Virus de la Fiebre Aftosa/genética , Argentina/epidemiología , Teorema de Bayes , Filogenia

RESUMEN

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a mucosal commensal of the lower genital tract in horses and is the most isolated bacterium causing endometritis in mares. The aim of this study was to determine the molecular diversity of S. zooepidemicus obtained from endometritis in mares in Buenos Aires province, Argentina. Thirty isolates obtained from the uterus of mares in 2005 and 2017 were studied. The MLST scheme was applied to identify the Argentinian genotypes and the clonal relationships and patterns of evolutionary descent were identified using the eBURST algorithm - goeBURST. Twenty six different Sequence types (STs) were identified, being only 11 of them previously reported in horses and also, from several host species and tissues. The other 15 STs were reported in Argentinian reproductive strains of mares in our study for the first time. The genotypes obtained from uterus in Argentina were not evenly distributed when all the published S. zooepidemicus STs were analysed, thus, it was not possible to establish that the same lineage circulates in our equine population. The fact that the identified genotypes were also reported in other countries, diverse samples and host species suggest that there is not a host, and an anatomical niche adaptation. Finally, the isolation of the same genotype in the vagina/clitoris and the uterus of the same mare highlights the versatility of S. zooepidemicus and its role as an opportunistic pathogen.

Asunto(s)

Endometritis , Genotipo , Enfermedades de los Caballos , Infecciones Estreptocócicas , Animales , Caballos/microbiología , Enfermedades de los Caballos/microbiología , Femenino , Argentina , Endometritis/veterinaria , Endometritis/microbiología , Infecciones Estreptocócicas/veterinaria , Infecciones Estreptocócicas/microbiología , Variación Genética , Tipificación de Secuencias Multilocus/veterinaria , Útero/microbiología , Streptococcus/genética , Streptococcus/aislamiento & purificación , Streptococcus/clasificación , Streptococcus equi/genética , Streptococcus equi/aislamiento & purificación , Streptococcus equi/clasificación

RESUMEN

The genus Hepatozoon consists of apicomplexan protozoans that affect mammals, birds, amphibians, and reptiles. In dogs, the Hepatozoon species include H. canis and H. americanum, which are transmitted by the Rhipicephalus sanguineus tick and cause nonspecific signs, such as fever, weight loss, diarrhea, and blood disorders. These protozoans have a worldwide distribution in Europe, Asia, Africa, and North and South America, including Colombia. The aim of this study was to determine the prevalence and risk factors associated with H. canis in the urban and rural areas of Ibagué, Colombia. Blood samples were collected from 308 dogs (180 rural areas and 128 urban areas). Collected data included dog breed, sex, age, environmental factors, and the presence of ectoparasites. A fragment of the 18S rRNA gene was amplified by PCR for detection of the pathogen and confirmed by sequencing. Among the 308 samples, 14 were positive (14/308, 4.5%) for the presence of H. canis. The partial sequence of the 18S rRNA gene showed identity values >98% with H. canis, forming a cluster with sequences from Latin America. An epidemiological survey found two protective factors: most of the time at home (P=0.055) and overnight stay at home (P=0.03). This is the first molecular study of the prevalence and phylogeny analysis of H. canis in Ibagué, Colombia. The findings may help determine risk factors and enhance our understanding of the geographic distribution of H. canis in Colombia.

Asunto(s)

Coccidiosis , Enfermedades de los Perros , Eucoccidiida , ARN Ribosómico 18S , Animales , Perros , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/epidemiología , Coccidiosis/veterinaria , Coccidiosis/epidemiología , Coccidiosis/parasitología , Femenino , Masculino , Colombia/epidemiología , Eucoccidiida/genética , Eucoccidiida/aislamiento & purificación , ARN Ribosómico 18S/genética , Prevalencia , Factores de Riesgo , Filogenia