ABSTRACT Objective To conduct a systematic review of original peer-reviewed studies, containing data on the identification of SARS-CoV-2 in clinical samples of amniotic fluid, placenta or membranes, umbilical cord blood, and human milk, from women with a clinically or confirmed diagnosis of COVID-19. These studies should have been published after the guide for the management of patients with COVID-19 from World Health Organization guide (available in March 13, 2020). Results Seventeen studies were included, in which 143 clinical samples were identified (38 of amniotic fluid; 34 of placentas or membranes; 39 from umbilical cord blood and 32 from human milk). Among the 143 samples, nine were positive for SARS-CoV-2 RNA (one amniotic fluid sample obtained before rupturing the membranes; six samples of placenta or membranes, although authors indicate the possibility of contamination by maternal blood in three of these, and two samples of human milk). Conclusions Following our search criteria, we found no studies that demonstrate the detection of SARS-CoV-2, in conjunction with viral isolation and the evaluation of the infective capacity of viral particles, in clinical samples of amniotic fluid, placenta or membranes, umbilical cord blood and human milk, from women with a confirmed or clinical diagnosis of COVID-19. However, vertical transmission cannot be ruled out, larger studies are required that ideally locatein situRNA and protein of SARS-CoV-2, as well as isolation that demonstrate the infective capacity of the viral particles.

RESUMEN Objetivo Efectuar una revisión sistemática de estudios originales revisados por pares que contengan datos acerca de la identificación de SARS-CoV-2 en muestras clínicas de líquido amniótico, placenta o membranas, sangre del cordón umbilical y leche humana de mujeres con diagnóstico clínico o confirmado de COVID-19. Para ser incluidos en esta revisión sistemática, los estudios debieron ser aceptados después de la publicación de la guía para el manejo de pacientes con COVID-19 de la Organización Mundial de la Salud (disponible el 13 de marzo de 2020). Resultados Se incluyeron 17 estudios en los que se identificaron 143 muestras clínicas (38 de líquido amniótico, 34 de placentas o membranas, 39 de sangre del cordón umbilical y 32 de leche humana), de las cuales nueve resultaron positivas para ARN de SARS-CoV-2 (una de líquido amniótico obtenida antes de romper las membranas; seis de placenta o membranas, aunque los autores indican la posibilidad de contaminación por sangre materna en tres de ellas; y dos de leche humana). Conclusiones Siguiendo nuestros criterios de búsqueda no encontramos estudios que demuestren la detección de SARS-CoV-2, a la par del aislamiento viral y la evaluación de la capacidad infectiva de las partículas virales, en muestras clínicas de líquido amniótico, placenta o membranas, sangre del cordón umbilical y leche humana, de mujeres con diagnóstico clínico o confirmado de COVID-19. Sin embargo, la transmisión vertical no puede descartarse y se requieren estudios de mayor tamaño que empleen idealmente técnicas de localizaciónin situde ARN y proteína de SARS-CoV-2, así como de aislamiento viral que compruebe la capacidad infectiva de las partículas virales.

RESUMEN Objetivo Efectuar una revisión sistemática de estudios originales revisados por pares que contengan datos acerca de la identificación de SARS-CoV-2 en muestras clínicas de líquido amniótico, placenta o membranas, sangre del cordón umbilical y leche humana de mujeres con diagnóstico clínico o confirmado de COVID-19. Para ser incluidos en esta revisión sistemática, los estudios debieron ser aceptados después de la publicación de la guía para el manejo de pacientes con COVID-19 de la Organización Mundial de la Salud (disponible el 13 de marzo de 2020). Resultados Se incluyeron 17 estudios en los que se identificaron 143 muestras clínicas (38 de líquido amniótico, 34 de placentas o membranas, 39 de sangre del cordón umbilical y 32 de leche humana), de las cuales nueve resultaron positivas para ARN de SARS-CoV-2 (una de líquido amniótico obtenida antes de romper las membranas; seis de placenta o membranas, aunque los autores indican la posibilidad de contaminación por sangre materna en tres de ellas; y dos de leche humana). Conclusiones Siguiendo nuestros criterios de búsqueda no encontramos estudios que demuestren la detección de SARS-CoV-2, a la par del aislamiento viral y la evaluación de la capacidad infectiva de las partículas virales, en muestras clínicas de líquido amniótico, placenta o membranas, sangre del cordón umbilical y leche humana, de mujeres con diagnóstico clínico o confirmado de COVID-19. Sin embargo, la transmisión vertical no puede descartarse y se requieren estudios de mayor tamaño que empleen idealmente técnicas de localizaciónin situde ARN y proteína de SARS-CoV-2, así como de aislamiento viral que compruebe la capacidad infectiva de las partículas virales.

ABSTRACT Objective To conduct a systematic review of original peer-reviewed studies, containing data on the identification of SARS-CoV-2 in clinical samples of amniotic fluid, placenta or membranes, umbilical cord blood, and human milk, from women with a clinically or confirmed diagnosis of COVID-19. These studies should have been published after the guide for the management of patients with COVID-19 from World Health Organization guide (available in March 13, 2020). Results Seventeen studies were included, in which 143 clinical samples were identified (38 of amniotic fluid; 34 of placentas or membranes; 39 from umbilical cord blood and 32 from human milk). Among the 143 samples, nine were positive for SARS-CoV-2 RNA (one amniotic fluid sample obtained before rupturing the membranes; six samples of placenta or membranes, although authors indicate the possibility of contamination by maternal blood in three of these, and two samples of human milk). Conclusions Following our search criteria, we found no studies that demonstrate the detection of SARS-CoV-2, in conjunction with viral isolation and the evaluation of the infective capacity of viral particles, in clinical samples of amniotic fluid, placenta or membranes, umbilical cord blood and human milk, from women with a confirmed or clinical diagnosis of COVID-19. However, vertical transmission cannot be ruled out, larger studies are required that ideally locatein situRNA and protein of SARS-CoV-2, as well as isolation that demonstrate the infective capacity of the viral particles.

ABSTRACT The purpose of this work was to perform by Whole Genomic Sequencing (WGS) a characterization of tuberculosis isolates circulating in the central region of Veracruz, Mexico, and to determine its geographical distribution. The genome of 25 clinical isolates of tuberculosis patients, recovered from central zone of Veracruz, Mexico, were sequenced and the information obtained was used to characterize lineage, prediction of drug resistance, identification of clonal complexes, and finally correlated with the geolocalization data. Isolates analyzed were included into seven L4 sublineages, most frequent was X3; X1 (4.1.1.3) in 35%. rpoBSer450Leu polymorphism was the most frequently found variant. Sublineage Haarlem (4.1.2) had the widest distribution, found in five municipalities. Of the of two clonal complexes found, the most abundant included eight isolates, with X3/X1 lineage, placed in two municipalities. Combination of WGS and geographic information system was very useful for the identification of sublineages, clonal complexes, and their geographical dispersion with important implications in the epidemiological surveillance and clinical control of TB.

ABSTRACT Background and aim: the aim of the study was to use a validated questionnaire to identify factors associated with the development of gastric cancer (GC) in the Mexican population. Methods: the study included cases and controls that were paired by sex and ± 10 years of age at diagnosis. In relation to cases, 46 patients with a confirmed histopathological diagnosis of adenocarcinoma-type GC, as reported in the hospital records, were selected, and 46 blood bank donors from the same hospital were included as controls. The previously validated Questionnaire to Find Factors Associated with Gastric Cancer (QUFA-GC(c)) was used to collect data. Odds ratio (OR) and 95% confidence interval (IC) were estimated via univariate analysis (paired OR). Multivariate analysis was performed by logistic regression. A decision tree was constructed using the J48 algorithm. Results: an association was found by univariate analysis between GC risk and a lack of formal education, having smoked for ≥ 10 years, eating rapidly, consuming very hot food and drinks, a non-suitable breakfast within two hours of waking, pickled food and capsaicin. In contrast, a protective association against GC was found with taking recreational exercise and consuming fresh fruit and vegetables. No association was found between the development of GC and having an income that reflected poverty, using a refrigerator, perception of the omission of breakfast and time period of alcoholism. In the final multivariate analysis model, having no formal education (OR = 17.47, 95% CI = 5.17-76.69), consuming a non-suitable breakfast within two hours of waking (OR = 8.99, 95% CI = 2.85-35.50) and the consumption of capsaicin ˃ 29.9 mg capsaicin per day (OR = 3.77, 95% CI = 1.21-13.11) were factors associated with GC. Conclusions: an association was found by multivariate analysis between the presence of GC and education, type of breakfast and the consumption of capsaicin. These variables are susceptible to intervention and can be identified via the QUFA-GC(c).