Were metabolic and other chronic diseases the driven onset epidemic forces of COVID-19 in Mexico?

The underline hypothesis of this study was that SARS-CoV-2 can infect individuals regardless of health condition, sex, and age in opposition to the classical epidemiological assumption of an identifiable susceptible subpopulation for epidemic development. To address this issue, a population cohort with 24.4 million metadata associated with 226,089 official RT-qPCR positive and 283,450 negative cases, including 27,769 deceased, linked putatively to B.1. and B.1.1. SARS-CoV-2 lineages were analyzed. The analysis baseline was to determine the infection and mortality structure of the diseased cohort at the onset-exponential phase of the first epidemic wave in Mexico under the assumption of limited herd immunity. Individuals with nonchronic diseases (NOCDs) were compared with those exhibiting at least one of 10 chronic diseases (CDs) adjusted by age and sex. Risk factors for infection and mortality were estimated with classification and regression tree (CART) and cluster analysis based on Spearman's matrix of rho-values in RStudio®, complemented with two proposed mortality indices. SARS-CoV-2 infection was independent of health condition (52.8% NOCD vs. 47.2% CDs; p = 0.001-0.009) but influenced by age >46 in one risk analysis scenario (p < 0.001). Sex contributed 9.7% to the overall risk. The independent effect was supported by the health structure of negative cases with a similar tendency but a higher proportion of NOCDs (61.4%, p = 0.007). The infection probability in individuals with one CD was determined by the disease type and age, which was higher in those older individuals (≥56 years) exhibiting diabetes (12.3%, cp = 0.0006), hypertension (10.1%, cp < 0.0001), and obesity (7.8%, cp = 0.001). In contrast, the mortality risk was heavily influenced by CD conditioned by sex and age, accounting for 72.3% of total deaths (p = 0.001-0.008). Significant mortality risk (48%) was comprised of women and men (w, m) aged ≥56 years with diabetes (19% w and 27.9% m, cp < 0.0004), hypertension (11.5% w, cp = 0.0001), and CKD (3.5% w and 5.3% m, cp = 0.0009). Older people with diabetes and hypertension comorbidity increased the risk to 60.5% (p = 0.001). Based on a mortality-weighted index, women were more vulnerable to preexisting metabolic or cardiovascular diseases. These findings support our hypothesis and justify the need for surveillance systems at a communitarian level. This is the first study addressing this fundamental epidemiological question.

Surveillance Web System and Mouthwash-Saliva qPCR for Labor Ambulatory SARS-CoV-2 Detection and Prevention.

This study provides a safe and low-cost in-house protocol for RT-qPCR-based detection of SARS-CoV-2 using mouthwash-saliva self-collected specimens to achieve clinical and epidemiological surveillance in a real-time web environment applied to ambulatory populations. The in-house protocol comprises a mouthwash-saliva self-collected specimen, heat virus inactivation, and primers to target virus N-gene region and the human RPP30-gene. Aligning with 209 SARS-CoV-2 sequences confirmed specificity including the Alpha variant from the UK. Development, validation, and statistical comparison with official nasopharyngeal swabbing RT-qPCR test were conducted with 115 specimens of ambulatory volunteers. A web-mobile application platform was developed to integrate a real-time epidemiological and clinical core baseline database with mouthwash-saliva RT-qPCR testing. Nine built-in algorithms were generated for decision-making on testing, confining, monitoring, and self-reports to family, social, and work environments. Epidemiological and clinical follow-up and SARS-CoV-2 testing generated a database of 37,351 entries allowing individual decision-making for prevention. Mouthwash-saliva had higher sensitivity than nasopharyngeal swabbing in detecting asymptomatic and mild symptomatic cases with 720 viral copy number (VCN)/mL as the detection limit (Ct = 37.6). Cycling threshold and viral loading were marginally different (p = 0.057) between asymptomatic (35 Ct ± 2.8; 21,767.7 VCN/mL, range 720-77,278) and symptomatic (31.3 Ct ± 4.5; 747,294.3 VCN/mL, range 1433.6-3.08 × 106). We provided proof-of-concept evidence of effective surveillance to target asymptomatic and moderate symptomatic ambulatory individuals based on integrating a bio-safety level II laboratory, self-collected, low-risk, low-cost detection protocol, and a real-time digital monitoring system. Mouthwash-saliva was effective for SARS-CoV-2 sampling for the first time at the community level.

The First exploratory spatial distribution analysis of tuberculosis and associated factors in Tonala, Mexico.

INTRODUCTION: The US-Mexico region is at high risk of elevated tuberculosis (TB) incidence due to mobility and migration. Knowledge of how socio-demographic factors varies geographically, provides clues to understanding the determinants of tuberculosis and may provide guidance for regional prevention and control strategies to improve public health in Mexico. The aim of the present study was to describe the epidemiologic characteristics and spatial patterns of the incidence of tuberculosis in Tonala, Jalisco (Mexico) from 2013-2015. METHODOLOGY: The Surveillance System Database from the Health Department, complemented by information from the National Institute of Statistics and Geography, was used to obtain data for a spatial-temporal analysis of TB cases. For the geographical analysis map creation and geoinformation storing, ArcGIS software was used. RESULTS: This study sought to characterize problem areas and jurisdictional locations of TB via a spatial approach based on analyses of case distributions and individual patient variables. The study found that tuberculosis cases were dispersed throughout Tonala County and were mainly concentrated on the Guadalajara city border. The TB cases were mainly individuals between 31 and 45 years old. Most of the cases reported during the observation period were male patients, and most cases primarily had lung involvement; however, there were quite a few cases with lymph node and intestinal disease. CONCLUSION: Our findings show that TB cases are essentially located in areas close to the city of Guadalajara and that most TB cases were pulmonary cases spread throughout the whole jurisdiction.

[Using geo-intelligence to estimate risk of introduction of influenza type A in MexicoCenário de risco de introdução do vírus da influenza A no México estimado com o uso de inteligência geográfica]. / Escenario de riesgo de introducción de la influenza tipo A en México estimado mediante geointeligencia.

OBJECTIVE: Estimate the probabilistic potential of introduction of the causative agent of influenza type A in Mexico, using geo-intelligence applied to health. METHODS: Ecological study of 1,973 influenza outbreaks with a high degree of pathogenicity, worldwide during the period 2014-2016. Geospatial modeling was developed with geo-intelligence tools such as spatial representation, a relational model, spatial characterization of the inoculum source with the maximum entropy model and the receiver operating characteristic (ROC) curve, using multicriteria spatial analysis. This was validated with the Moran index and geographically weighted regression. RESULTS: Isochrones (at an initial distance of 548 km) were estimated for health risks and their exponential growth; at the fourth isochrone, the east and west coasts of the United States of America and a part of Central America were identified as possible areas that favor the introduction of the pathogen. Also, a COR curve = 0.923 was obtained; two risk periods for introduction were identified (September-March and April-August, with north-south and south-north trajectories, respectively) with high positive autocorrelation for geospatial modeling; and in one scenario, more than half of Mexico was found to be at high risk of introduction, with an estimated 78 million people exposed. A positive association was identified between significant risk areas (p < 0.001). CONCLUSION: More than 50% of Mexican territory was found to be at risk of introduction of the causative agent of influenza type A, with approximately 70% of the population exposed.

OBJETIVO: Estimar o cenário probabilístico em potencial de introdução do vírus da influenza A no México com o uso de inteligência geográfica em saúde. MÉTODOS: Estudo ecológico de 1.973 surtos mundiais de influenza de alta patogenicidade ocorridos no período 2014­2016. Foi desenvolvido um modelo geoespacial com ferramentas de inteligência geográfica, como representação espacial, modelo de conexidade, caracterização espacial da fonte de inóculo com o modelo de máxima entropia e curva ROC (receiver operating characteristic) com avaliação espacial por múltiplos critérios e validação com o índice de Moran e regressão geograficamente ponderada. RESULTADOS: Foram estimadas isócronas do risco de saúde com uma distância de 548 km e o crescimento exponencial destes linhas; até a quarta isócrona, foram identificadas as costas leste e oeste dos Estados Unidos (EUA) e parte da América Central como possível superfície que favorece a introdução do vírus. Foi também estimada uma curva ROC de 0,923, sendo identificados dois períodos de risco de introdução do vírus (setembro­março e abril­agosto) com trajetórias de norte-sul e sul-norte, respectivamente, com elevada autocorrelação positiva para o modelo geoespacial. Foi estimado um cenário em que mais da metade do México apresenta alto risco de introdução do vírus da influenza, com 78 milhões de pessoas expostas. E foi observada uma associação positiva entre as áreas de risco significativo (P < 0,001). CONCLUSÃO: Observa-se que mais de 50% do território mexicano está sob risco de introdução do vírus da influenza A, com cerca de 70% da população exposta.

Genetic diversity of Mycobacterium tuberculosis and transmission associated with first-line drug resistance: a first analysis in Jalisco, Mexico.

OBJECTIVES: The objectives of this study were to analyse the frequency of gene mutations associated with antitubercular drug resistance in clinical samples from the population of Jalisco State (Mexico) and to evaluate the genetic variability of Mycobacterium tuberculosis and multidrug-resistant (MDR) M. tuberculosis strains to describe the frequency of various families. METHODS: Clinical isolates of M. tuberculosis obtained from Jalisco State were analysed. Isolates were subjected to drug susceptibility testing, and mutations were characterised by sequencing, followed by genotyping using spoligotyping and mycobacterial interspersed repetitive units-variable-number of tandem repeats (MIRU-VNTR). Moreover, the prevalence of mutations was analysed by phylogenetic lineages. RESULTS: Resistant strains were analysed by sequencing of katG, inhA and rpoB genes to determine the presence of mutations associated with isoniazid and rifampicin resistance. In MDR, monoresistant and polyresistant isolates, mutations were found in 17 (54.84%) of 31 strains. Spoligotyping identified six different strain lineages [T1 (25.40%), H3 (7.94%), MANU (4.76%), X1 (3.17%), EAI5 (1.59%) and LAM1 (1.59%)], with the remaining strains identified as orphans. In additional tree-based identification, a dendrogram of spoligotype patterns generated five different similarity clusters. When combining 24-loci MIRU-VNTR and spoligotyping approaches, the results shows that there is no cluster formation, indicating low transmission of the samples. CONCLUSIONS: This study using spoligotyping and MIRU-VNTR showed that the analysed strains were not related to each other since no two identical strains were found. Families with the highest prevalence in the study were orphans followed by T family.

Analysis of Genetic Variation in Brevipalpus yothersi (Acari: Tenuipalpidae) Populations from Four Species of Citrus Host Plants.

We studied species diversity and genetic variation among populations of Brevipalpus mites from four species of citrus host plants. We sampled mites on orange, lime, grapefruit and mandarin trees from orchards at six localities distributed in the five most important citrus producing states in Mexico. Genetic variation among citrus host plants and localities were assessed by analysis of nucleotide sequence data from fragments of the mitochondrial cytochrome oxidase subunit I (COI). Both Brevipalpus yothersi and B. californicus were found at these sites, and B. yothersi was the most abundant species found on all citrus species and in all localities sampled. B. californicus was found mainly on orange and mandarin and only in two of the states sampled. AMOVA and haplotype network analyses revealed no correlation between B. yothersi genetic population structure and geographical origin or citrus host plant species. Considering that a previous study reported greater genetic diversity in B. yothersi populations from Brazil than we observed in Mexico, we discuss the possibility that the Mexican populations may have originated in the southern region of America.

Synchronicity of pollination and inoculation with Claviceps africana and its effects on pollen-pistil compatibility and seed production in sorghum.

Sorghum ergot (caused by Claviceps africana) is a disease that affects sorghum seed development and yield. The interaction between pollen tube growth and hyphal development determines whether ovaries will be fertilized or colonized. Thus their respective deposition times on the stigma are critical. The effect of the time interval between pollination and inoculation on stigma receptivity and seed production was measured under field conditions in the male-sterile line A9 at Montecillo, State of México (2240m altitude). Pollination and inoculation treatments, from simultaneous application to 2 and 4h difference, were imposed when all stigmas on the panicle had emerged. Control panicles were either only pollinated or only inoculated. Eighteen hours later, pollen grains that adhered to, and germinated within the stigma, pollen tubes in the style and ovary, and fertilized pistils were counted. Pistils showing some disease expression (germinated spores, mycelium growth, or tissue necrosis) at 18, 48, and 72h were recorded. The number of diseased florets was registered at the dough growth stage, while number of seeds, grain yield and 100-seeds weight was measured at the physiological maturity. The pathogen applied in a water suspension of macro and secondary conidia caused a decrease in stigma receptivity; the greatest decrease (40-60%) occurred when the pollen and the inoculum were deposited almost simultaneously, regardless of which was deposited first. The route of the pollen tube was also the route for fungal infection. On average, treatments first inoculated had 60% more diseased florets and 36% less grain yield, 30% fewer seeds and seed size decreased 8%, than those first pollinated.