The Impact of the Mycobacterium tuberculosis RDRio Subfamily on Multidrug-Resistant Tuberculosis in Latin America: A Comprehensive Review.

Latin American region is a high-burden setting for tuberculosis where multidrug-resistant tuberculosis (MDR-TB) is among the main challenge to move forward the End TB Strategy goals. It has been shown that MDR-TB is associated to certain Mycobacterium tuberculosis (MTB) lineages like L2-Beijing sublineage or L4-LAM. Although L2-Beijing is present in South America, the L4 lineage is the most prevalent with values ranging from 75% to 99% depending on the country. Within L4, Latin American-Mediterranean (LAM) family is the most prevalent. Moreover, within LAM, RDRio subfamily is present in high prevalence in several countries in South America like Venezuela or Brazil. RDRio has been associated to MDR-TB in several studies in Brazil but more epidemiological information is needed for South America. Here we discuss the problem of MDR-TB in Latin America and the potential threat that RDRio could represent. At this time, more molecular epidemiology studies are necessary to improve TB surveillance programs in Latin America by tracking MTB strains potentially responsible for MDR-TB spread.

First report of Bartonella henselae and Bartonella clarridgeiae carriage in stray cats from Ecuador and its link to a cat scratch disease outbreak in 2022.

INTRODUCTION: The genus Bartonella includes species and subspecies of fastidious, facultative intracellular Gram-negative bacilli that infect a wide variety of mammalian reservoirs including cats and humans. In 2022, the Ecuadorian Ministry of Health reported an outbreak of cat scratch disease caused by B. henselae in the city of Guayaquil. Therefore, we aimed to characterize the presence of Bartonella spp. in domestic and stray cats from the area of Guayaquil where the outbreak happened in 2022. METHODS: Whole blood samples of 100 domestic and stray cats were collected. Riboflavin synthase (ribC) and 16S rRNA genes detection was performed by PCR using Bartonella spp. specific primers, followed by Sanger sequencing and phylogenetic analysis. RESULTS: 14 cats were positive for Bartonella spp. carriage. Phylogenetic analysis confirmed the presence of 12 cats infected with B. henselae and 2 cats with B. clarridgeiae. CONCLUSIONS: There is a high prevalence of Bartonella spp. carriage in cats in the city of Guayaquil within the area where a recent cat scratch disease outbreak happened. Considering the high presence of cats and other domestic and stray animals in the city of Guayaquil, a One Health approach for surveillance and prevention of zoonotic diseases like cat scratch disease is needed.

Epidemiology of marine turtle fibropapillomatosis and tumour-associated chelonid alphaherpesvirus 5 (ChHV5; Scutavirus chelonidalpha5) in North-Western Mexico: a scoping review implementing the one health approach.

Fibropapillomatosis (FP) - tumour-associated chelonid alphaherpesvirus 5 (ChHV5; Scutavirus chelonidalpha5) - is a disease that affect marine turtles around the world, and characterized by the formation of cutaneous tumours that can appear anywhere on the body. We carried out a thorough literature search (from 1990 to 2024) in the feeding sites of North-western Mexico, a region that hosts important habitats for feeding, development, and reproduction for five of the seven existing sea turtle species. We found 18 reports recording a total of 32 cases of FP and/or ChHV5/Scutavirus chelonidalpha5 in coastal and insular areas of North-western Mexico. Baja California Sur resulted with the highest number of cases (75%). While the first case of ChHV5/Scutavirus chelonidalpha5 infection was reported in 2004, the presence of FP tumours was reported in 2014 and became more frequent between 2019 and 2024. The affected species were black, Chelonia mydas (50%), olive ridley, Lepidochelys olivacea (46.8%) and loggerhead turtles, Caretta caretta (3.2%). Tumours occurred mainly in anterior flippers (46.1%) and neck (22.5%), and most had a nodular and verrucous appearance with a rough surface. In the study region, there is a potential sign of the emergence of the ChHV5/Scutavirus chelonidalpha5 infections and FP disease during the last 20 years, with a rapid increase during the last 10 years. As long as infections by ChHV5/Scutavirus chelonidalpha5 and the prevalence of the FP disease may be potentially influenced by anthropogenic activities, a One Health approach is needed to understand and improve sea turtles' health.

A first insight into seropositivity of Neospora caninum and associated risk factors in free-roaming dogs from Ecuador.

Neosporosis is a worldwide parasitic disease caused by the protozoan Neospora caninum. It can cause economic losses to farmers due to its relationship with abortions and neonatal mortality in cows. Dogs play a key role in its spread as they are considered definitive hosts. In this study, we determined for the first time the seropositivity of N. caninum infection in dogs from Ecuador and evaluated potential risk factors. A total number of 339 free-roaming dogs from the three main regions of Ecuador (Coastal, Andean, and Amazonian regions) were included in the study and classified either as urban or rural dogs. Serum samples were collected from November 2018 to May 2019, and analyzed with a commercial ELISA test. An overall seropositivity of 6.8 % (CI: 95 %, 2.8 % - 11.7 %) was found in N. caninum infection with no statistical differences among regions or urban/rural dogs. This is the first surveillance of N. caninum in Ecuador, confirming a country-wide distribution of this pathogen. Considering the large populations of free-roaming dogs in Ecuador, a One Health approach for surveillance and managing N. caninum in dogs is needed to protect either livestock or wildlife.

Prevalence, drug resistance, and genotypic diversity of the RDRio subfamily of Mycobacterium tuberculosis in Ecuador: a retrospective analysis for years 2012-2016.

Introduction: A major sublineage within the Mycobacterium tuberculosis (MTB) LAM family characterized by a new in-frame fusion gene Rv3346c/55c was discovered in Rio de Janeiro (Brazil) in 2007, called RDRio, associated to drug resistance. The few studies about prevalence of MTB RDRio strains in Latin America reported values ranging from 3% in Chile to 69.8% in Venezuela, although no information is available for countries like Ecuador. Methods: A total of 814 MTB isolates from years 2012 to 2016 were screened by multiplex PCR for RDRio identification, followed by 24-loci MIRU-VNTR and spoligotyping. Results: A total number of 17 MTB RDRio strains were identified, representing an overall prevalence of 2.09% among MTB strains in Ecuador. While 10.9% of the MTB isolates included in the study were multidrug resistance (MDR), 29.4% (5/17) of the RDRio strains were MDR. Discussion: This is the first report of the prevalence of MTB RDRio in Ecuador, where a strong association with MDR was found, but also a very low prevalence compared to other countries in Latin America. It is important to improve molecular epidemiology tools as a part of MTB surveillance programs in Latin America to track the transmission of potentially dangerous MTB stains associated to MDR TB like MTB RDRio.

Rapid and accurate identification and differentiation of Mycobacterium tuberculosis and non-tuberculous mycobacteria using PCR kits available in a high-burden setting.

Infections caused by mycobacteria, including Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), are a major public health issue worldwide. An accurate diagnosis of mycobacterial species is a challenge for surveillance and treatment, particularly in high-burden settings usually associated with low- and middle-income countries. In this study, we analyzed the clinical performance of two commercial PCR kits designed for the identification and differentiation of MTBC and NTM, available in a high-burden setting such as Ecuador. A total of 109 mycobacteria isolates were included in the study, 59 of which were previously characterized as M. tuberculosis and the other 59 as NTM. Both kits displayed great clinical performance for the identification of M. tuberculosis, with 100% sensitivity. On the other hand, for NTM, one of the kits displayed a good clinical performance with a sensitivity of 94.9% (CI 95%: 89-100%), while the second kit had a reduced sensitivity of 77.1% (CI 95%: 65-89%). In conclusion, one of the kits is a fast and reliable tool for the identification and discrimination of MTBC and NTM from clinical isolates.

Population structure of Mycobacterium tuberculosis in El Oro: A first insight into Ecuador-Peru tuberculosis transmission.

BACKGROUND: Tuberculosis (TB) is a major public health concern in Ecuador and Peru, both settings of high burden of drug resistance TB. Molecular epidemiology tools are important to understand the transmission dynamics of Mycobacterium tuberculosis Complex (MTBC) and to track active transmission clusters of regional importance. This study is the first to address the transmission of TB between Peru and Ecuador through the population structure of MTBC lineages circulating in the Ecuadorian border province of "El Oro". METHODS: A total number of 56 MTBC strains from this province for years 2012-2015 were included in the study and analyzed by 24-loci MIRU-VNTR and spoligotyping. RESULTS: Genotyping revealed a high degree of diversity for MTBC in "El Oro", without active transmission clusters. MTBC L4 was predominant, with less than 2% of strains belonging to MTBC L2-Beijing. CONCLUSIONS: These results may suggest that TB dynamics in this rural and semi-urban area would not be linked to highly transmitted strains like MTBC L2-Beijing from Peru, but related to TB relapse; although further studies with larger MTBC cultures collection from recent years are needed. Nevertheless, we recommend to reinforce TB surveillance programs in remote rural settings and border regions in Ecuador.

A first insight into tuberculosis transmission at the border of Ecuador and Colombia: a retrospective study of the population structure of Mycobacterium tuberculosis in Esmeraldas province.

Objective: Tuberculosis (TB) is a major public health concern in Ecuador and Colombia, considering that both countries are high-burden TB settings. Molecular epidemiology is crucial to understand the transmission dynamics of Mycobacterium tuberculosis complex (MTBC) and to identify active transmission clusters of regional importance. Methods: We studied the potential transmission of TB between Colombia and Ecuador through the analysis of the population structure of MTBC lineages circulating in the Ecuadorian province of Esmeraldas at the border with Colombia. A total of 105 MTBC strains were characterized by 24-loci MIRU-VNTR and spoligotyping. Results: MTBC lineage 4 is only present in Esmeraldas; no MTBC strains belonging to Lineage 2-sublineage Beijing were found despite its presence in other provinces of Ecuador and, in Colombia. Genotyping results revealed a high degree of diversity for MTBC in Esmeraldas: Neither active transmission clusters within this province nor including MTBC strains from Colombia or other provinces of Ecuador were found. Conclusion: Our data suggest that tuberculosis dynamics in this rural and isolated area may be not related to highly transmitted strains but could be influenced by other health determinants that favor TB relapse such as poverty and poor health system access. Further studies including a larger number of MTBC strains from Esmeraldas are necessary to test this hypothesis.

Coinfection of SARS-CoV-2 with other respiratory pathogens in outpatients from Ecuador.

Worldwide, the COVID-19 pandemic caused by SARS-CoV-2 has enormously impacted healthcare systems, especially in low and middle-income countries. Coinfections with respiratory pathogens in COVID-19 patients may contribute to worse outcomes. This study identified the presence of 12 viral coinfections and pneumococcal carriers among individuals with SARS-CoV-2 infection in outpatient and community settings in Ecuador. From January 2020 to November 2021, 215 nasopharyngeal and nasal swabs were taken from individuals who reported symptoms of COVID-19 or had known exposure to someone with confirmed or suspected COVID-19. One hundred fifty-eight tested positive for SARS-CoV-2 by RT-qPCR and coinfections were detected in 12% (19/158) of SARS-CoV-2-positive patients; the most frequent coinfection was with influenza A virus at 4.4% (7/158; 95% CI: 1.2-7.6), followed by respiratory syncytial virus with 3.1% (5/158; 95% CI: 0.4-5.8), and finally rhinovirus and human coronavirus NL63 with 1.2% (2/158). Pneumococcal carriage was detected in 3.7% (6/158; 95% CI: 0.76-6.64) of SARS-CoV-2 cases. Influenza B, adenovirus, human metapneumovirus (HMPV), parainfluenza virus types 1, 2, and 3, and human coronavirus HKU1 were undetected. To our knowledge, this is the first study of coinfection of SARS-CoV-2 and respiratory pathogens performed on outpatients in Latin America. The high proportion of outpatients with viral coinfections reported in our cohort allows us to suggest that testing for SARS-CoV-2 and other common respiratory pathogens should be carried out to ensure accurate diagnoses, prompt patient treatment, and appropriate isolation.

A tool for the cheap and rapid screening of SARS-CoV-2 variants of concern (VoCs) by Sanger sequencing.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging virus that, since March 2020, has been responsible for a global and ongoing pandemic. Its rapid spread over the past nearly 3 years has caused novel variants to arise. To monitor the circulation and emergence of SARS-CoV-2 variants, surveillance systems based on nucleotide mutations are required. In this regard, we searched in the spike, ORF8, and nucleocapsid genes to detect variable sites among SARS-CoV-2 variants. We describe polymorphic genetic regions that enable us to differentiate between the Alpha, Beta, Gamma, Delta, and Omicron variants of concern (VoCs). We found 21 relevant mutations, 13 of which are unique for Omicron lineages BA.1/BA.1.1, BA.2, BA.3, BA.4, and BA.5. This genetic profile enables the discrimination between VoCs using only four reverse transcription PCR fragments and Sanger sequencing, offering a cheaper and faster alternative to whole-genome sequencing for SARS-CoV-2 surveillance. IMPORTANCE Our work describes a new (Sanger sequencing-based) screening methodology for SARS-CoV-2, performing PCR amplifications of a few target regions to detect diagnostic mutations between virus variants. Using the methodology developed in this work, we were able to discriminate between the following VoCs: Alpha, Beta, Gamma, Delta, and Omicron (BA.1/BA.1.1, BA.2, BA.3, BA.4, and BA.5). This becomes important, especially in low-income countries where current methodologies like next-generation sequencing have prohibitive costs. Furthermore, rapid detection would allow sanitary authorities to take rapid measures to limit the spread of the virus and therefore reduce the probability of new virus dispersion. With this methodological approach, 13 previously unreported diagnostic mutations among several Omicron lineages were found.

Massive testing in the Galapagos Islands and low positivity rate to control SARS-CoV-2 spread during the first semester of the COVID-19 pandemic: a story of success for Ecuador and South America.

INTRODUCTION: During the first months of the COVID-19 pandemic in Latin America, countries like Ecuador, Peru and Colombia experienced chaotic scenarios with public health systems collapsing and lack of testing capacity to control the spread of the virus. In main cities like Guayaquil in Ecuador, dramatic situations such as corpses in the streets were internationally broadcasted. METHODS: While the COVID-19 pandemic was devastating South America, SARS-CoV-2 transmission was successfully managed in the Galapagos Islands due to the implementation of a massive screening strategy including hospitalized and community-dwelling populations, and travel restrictions facilitated by its geographical location (972 km from the Ecuadorian continental territory). Floreana Island was one of the few locations in the world that remained COVID-19 free during 2020. RESULTS: In this study, we retrospectively analyzed the data related to SARS-CoV-2 massive testing campaigns from April to September 2020 in the Galapagos Islands, and found this territory to have the lowest positivity rate in South America (4.8-6.7%) and the highest testing ratio among Ecuadorian provinces (9.87% of the population, which is 2480 out of 25 124 inhabitants) during the first wave of the COVID-19 pandemic. CONCLUSION: This story of success was possible because of the interinstitutional collaboration between the regional government of Galapagos Islands (Consejo de Gobierno), the local authorities (Gobiernos Autonomos Descentralizados de Santa Cruz, San Cristobal and Isabela), the regional authorities from Ecuadorian Ministry of Health, the Agencia de Regulación y Control de la Bioseguridad y Cuarentena para Galápagos and Universidad de Las Américas.

Dog bites as a zoonotic risk in Ecuador: Need for the implementation of a One Health approach.

Rabies is a viral zoonotic disease that can infect all mammals and the main route of transmission to human is attributed to dog bites. Due to the limited information available about the rabies vaccination coverage, although Ecuador is supposed to be free of rabies, we conducted a retrospective study of the epidemiological surveillance records on the notification of dog attacks to humans in Guayaquil, the most populated city in Ecuador. The results showed an annual incidence rate of 105.6 dog bites per 100,000 inhabitants, where the most affected anatomical parts are the lower extremities; individuals from 1 to 14 years of age were the most affected age group (IC95% 1.42-1.92; p < 0.001). As for the severity of the wounds, most of them (65%) were mild. Moreover, 25% of the dogs were free roaming ones, and only 43% of the dogs with owner had a complete vaccination scheme against rabies virus. We found a important dog attack rate in Guayaquil city and more than half of the dogs involved were not vaccinated against rabies. Under a potential scenario of rabies circulation in canine population, there would be a serious risk for rabies transmission to humans. Hence, it is important to reinforce rabies surveillance and vaccination programs aligned to the One Health concept to manage this public health issue.

A recent distemper virus outbreak in the growing canine populations of Galapagos Islands: a persistent threat for the endangered Galapagos Sea Lion.

Canine Distemper Virus (CDV) is a highly contagious virus that can cross mammalian species barriers and has widespread impacts on both domestic animals and wildlife populations. This study describes a recent outbreak of CDV in the Galapagos Islands in 2019. A total number of 125 dogs with clinical signs compatible with CDV were included in this study. Nasal swabs were taken and analyzed by RT-qPCR for the detection of CDV, resulting in a positivity rate of 74.4% (IC95%, 66-81%). Among the CDV positive dogs, 82.2% presented with respiratory signs, 48.8% neurological signs, and 28.9% gastrointestinal signs. CDV has been previously reported in the domestic canine population of the Galapagos Islands in 2001 and 2004. The current study shows how CDV is still a threat for the endemic and endangered Galapagos sea lion, despite recent policies for dog population control and CDV vaccination.

Macro and microplastic intake in seafood variates by the marine organism's feeding behaviour: Is it a concern to human health?

Seafood is considered one of the healthiest sources of food intake for humans, mainly because of its high protein content. However, oceans are among the most polluted environments, and microplastics have been widely reported to be ingested, absorbed or bioaccumulated by marine organisms. The different feeding behaviour may contribute to infer the amounts of microplastic particles accidently intake by marine organisms. We investigated the putative levels of microplastics in different edible species of fish, molluscs, and crustaceans. Plastic fragments larger than 200 µm were detected in the digestive tract of 277 out of 390 specimens (71.5 ± 22.2%) of the 26 different species analysed. There was no evidence of microplastic translocation or bioaccumulation in the muscle tissue of fish, molluscs, and crustaceans. Organisms with carnivorous feeding habits had the highest prevalence of plastic ingestion (79 ± 9.4%), followed by planktivorous species (74 ± 15.5%), and detritivorous species (38 ± 36.9%), suggesting a transfer through the food chain. Moreover, we found evidence that species with less selective feeding habits may be the most affected by the ingestion of large microplastic particles. Our results provide further evidence to the ubiquitous presence of microplastics in marine organisms representing a direct threat to marine wildlife, and to human health with potential consequences for future generations according to the One Health initiatives approach.