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1.
N Engl J Med ; 385(10): 875-884, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34233097

RESUMO

BACKGROUND: Mass vaccination campaigns to prevent coronavirus disease 2019 (Covid-19) are occurring in many countries; estimates of vaccine effectiveness are urgently needed to support decision making. A countrywide mass vaccination campaign with the use of an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine (CoronaVac) was conducted in Chile starting on February 2, 2021. METHODS: We used a prospective national cohort, including participants 16 years of age or older who were affiliated with the public national health care system, to assess the effectiveness of the inactivated SARS-CoV-2 vaccine with regard to preventing Covid-19 and related hospitalization, admission to the intensive care unit (ICU), and death. We estimated hazard ratios using the extension of the Cox proportional-hazards model, accounting for time-varying vaccination status. We estimated the change in the hazard ratio associated with partial immunization (≥14 days after receipt of the first dose and before receipt of the second dose) and full immunization (≥14 days after receipt of the second dose). Vaccine effectiveness was estimated with adjustment for individual demographic and clinical characteristics. RESULTS: The study was conducted from February 2 through May 1, 2021, and the cohort included approximately 10.2 million persons. Among persons who were fully immunized, the adjusted vaccine effectiveness was 65.9% (95% confidence interval [CI], 65.2 to 66.6) for the prevention of Covid-19 and 87.5% (95% CI, 86.7 to 88.2) for the prevention of hospitalization, 90.3% (95% CI, 89.1 to 91.4) for the prevention of ICU admission, and 86.3% (95% CI, 84.5 to 87.9) for the prevention of Covid-19-related death. CONCLUSIONS: Our results suggest that the inactivated SARS-CoV-2 vaccine effectively prevented Covid-19, including severe disease and death, a finding that is consistent with results of phase 2 trials of the vaccine. (Funded by Agencia Nacional de Investigación y Desarrollo and others.).


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Imunogenicidade da Vacina , Vacinação em Massa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , COVID-19/mortalidade , Chile/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Estudos Prospectivos , Resultado do Tratamento , Vacinas de Produtos Inativados , Adulto Jovem
2.
Environ Health ; 20(1): 79, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34243768

RESUMO

BACKGROUND: Arsenic (As) exposure through drinking water is a global public health concern. Epigenetic dysregulation including changes in DNA methylation (DNAm), may be involved in arsenic toxicity. Epigenome-wide association studies (EWAS) of arsenic exposure have been restricted to single populations and comparison across EWAS has been limited by methodological differences. Leveraging data from epidemiological studies conducted in Chile and Bangladesh, we use a harmonized data processing and analysis pipeline and meta-analysis to combine results from four EWAS. METHODS: DNAm was measured among adults in Chile with and without prenatal and early-life As exposure in PBMCs and buccal cells (N = 40, 850K array) and among men in Bangladesh with high and low As exposure in PBMCs (N = 32, 850K array; N = 48, 450K array). Linear models were used to identify differentially methylated positions (DMPs) and differentially variable positions (DVPs) adjusting for age, smoking, cell type, and sex in the Chile cohort. Probes common across EWAS were meta-analyzed using METAL, and differentially methylated and variable regions (DMRs and DVRs, respectively) were identified using comb-p. KEGG pathway analysis was used to understand biological functions of DMPs and DVPs. RESULTS: In a meta-analysis restricted to PBMCs, we identified one DMP and 23 DVPs associated with arsenic exposure; including buccal cells, we identified 3 DMPs and 19 DVPs (FDR < 0.05). Using meta-analyzed results, we identified 11 DMRs and 11 DVRs in PBMC samples, and 16 DMRs and 19 DVRs in PBMC and buccal cell samples. One region annotated to LRRC27 was identified as a DMR and DVR. Arsenic-associated KEGG pathways included lysosome, autophagy, and mTOR signaling, AMPK signaling, and one carbon pool by folate. CONCLUSIONS: Using a two-step process of (1) harmonized data processing and analysis and (2) meta-analysis, we leverage four DNAm datasets from two continents of individuals exposed to high levels of As prenatally and during adulthood to identify DMPs and DVPs associated with arsenic exposure. Our approach suggests that standardizing analytical pipelines can aid in identifying biological meaningful signals.


Assuntos
Arsênio/efeitos adversos , Metilação de DNA/efeitos dos fármacos , Leucócitos/metabolismo , Mucosa Bucal/citologia , Efeitos Tardios da Exposição Pré-Natal/genética , Poluentes Químicos da Água/efeitos adversos , Adulto , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia
3.
Int J Infect Dis ; 107: 201-204, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33945868

RESUMO

Screening, testing and contact tracing plays a pivotal role in control of the COVID-19 pandemic. To enable this it is necessary to increase the testing capacity. This study compared a SARS-CoV-2 rapid antigen test (RAT) and RT-PCR in 842 asymptomatic individuals from Tarapacá, Chile. A sensitivity of 69.86%, specificity of 99.61%, PPV of 94.44% and NPP of 97.22% with Ct values (Ct > 27) that were significantly higher among individuals with false-negative RAT were reported. These results support the fact that RAT might have a significant impact on the identification of asymptomatic carriers in areas that lack suitable laboratories to perform SARS-CoV-2 real-time RT-PCR diagnostics, or the results take more than 24-48 h, as well as zones with high traffic of individuals such as border/customs, airports, interregional bus, train stations or in any mass testing campaign requiring rapid results.


Assuntos
Infecções Assintomáticas , Teste de Ácido Nucleico para COVID-19/métodos , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2 , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Pathogens ; 10(5)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924790

RESUMO

Coxiella burnetii is an intracellular bacterium and the cause of the zoonotic infection, Q fever. National surveillance data on C. burnetii seroprevalence is currently not available for any South American country, making efforts of public health to implement strategies to mitigate infections in different at-risk groups within the population extremely challenging. In the current study, we used two commercial anti-C. burnetii immunoassays to screen sera collected from a sample of the Chilean population as part of a 2016-2017 national health survey (n = 5166), nationwide and age-standardized. The seroprevalence for C. burnetii for persons ≥ 15 years was estimated to be 3.0% (95% CI 2.2-4.0), a level similar to national surveys from The Netherlands (2.4%) and USA (3.1%), but lower than Australia (5.6%). A linear increase of C. burnetii seropositivity was associated with an individual's age, with the peak seroprevalence 5.6% (95% CI 3.6-8.6) observed in the ≥65 years' group. C. burnetii seropositivity was significantly higher in the southern macro-zone 6.0% (95% CI 3.3-10.6) compared to metropolitan region 1.8% (95% CI 0.9-3.3), the former region being home to significant livestock industries, particularly dairy farming. These data will be useful to inform targeted strategies for the prevention of Q fever in at-risk populations in Chile.

5.
Rev Chilena Infectol ; 38(1): 54-60, 2021 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-33844793

RESUMO

BACKGROUND: Infectious diarrhea is still a major problem in public health, especially in children under 5 years of age. The identification of the etiologic agent is important for the clinical management of the diarrhea episode and, from the epidemiological point of view, to implement control measures. AIM: To determine the presence of gastrointestinal pathogens in children under five years of age with diarrhea in a Chilean rotavirus surveillance center. METHODS: Observational study in children under five years of age who were hospitalized for diarrhea at the Dr. Luis Calvo Mackenna Hospital from December 2015 to December 2019. Molecular detection was performed using the FilmArray gastrointestinal (FilmArray GI®) panel. RESULTS: We analyzed 493 diarrheal stool samples of children, 427 samples (87%) were positive and 66 samples (13%) were negative. Of positive samples, 174 samples (41%) and 253 samples (59%) were positive for one or more pathogen, respectively. In children under one year and the group between one and four years there was a predominance of infections caused by enteric virus. Rotavirus and norovirus were the most common virus in both age groups. The most frequent bacteria were EPEC (27%), C. difficile (17%), EAEC (14%) and Campylobacter (9%). In parasites, Giardia lamblia and Cryptosporidium were identified, in 3% and 1% of the total samples, respectively. CONCLUSIONS: The molecular detection system used allowed an increase in the detection of enteropathogens in children under five years of age. The information generated by this type of surveillance could help to characterize the episodes of diarrhea in the population and might be a tool to technically advise the authorities in the decision-making process for the implementation of control measures.


Assuntos
Clostridioides difficile , Criptosporidiose , Cryptosporidium , Infecções por Rotavirus , Rotavirus , Animais , Criança , Pré-Escolar , Chile/epidemiologia , Diarreia/epidemiologia , Fezes , Hospitais , Humanos , Lactente , Rotavirus/genética , Infecções por Rotavirus/epidemiologia , Vigilância de Evento Sentinela
6.
Animals (Basel) ; 11(1)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445721

RESUMO

Wild pigs (Sus scrofa) alter ecosystems, affect the economy, and carry diseases that can be transmitted to livestock, humans, and wildlife. Understanding wild pig movements and population structure data, including natural population boundaries and dispersal, may potentially increase the efficiency and effectiveness of management actions. We trapped, conducted aerial shootings, and hunted wild pigs from 2005 to 2009 in southern Texas. We used microsatellites to assist large-scale applied management. We quantify broad-scale population structure among 24 sites across southern Texas by computing an overall Fst value, and a Bayesian clustering algorithm both with and without considering the spatial location of samples. At a broad geographic scale, pig populations displayed a moderate degree of genetic structure (Fst = 0.11). The best partition for number of populations, based on 2nd order rate of change of the likelihood distribution, was K = 10 genetic clusters. The spatially explicit Bayesian clustering algorithm produced similar results, with minor differences in designation of admixed sites. We found evidence of past (and possibly ongoing) translocations; many populations were admixed. Our original goal was to identify landscape features, such as barriers or dispersal corridors, that could be used to aid management. Unfortunately, the extensive admixture among clusters made this impossible. This research shows that large-scale management of wild pigs may be necessary to achieve control and ameliorate damages. Reduction or cessation of translocations is necessary to prevent human-mediated dispersion of wild pigs.

7.
PLoS One ; 15(9): e0237515, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32898138

RESUMO

BACKGROUND: Regional variations in gastric cancer incidence are not explained by prevalence of Helicobacter pylori, the main cause of the disease, with several areas presenting high H. pylori prevalence but low gastric cancer incidence. The IARC worldwide H. pylori prevalence surveys (ENIGMA) aim at systematically describing age and sex-specific prevalence of H. pylori infection around the world and generating hypotheses to explain regional variations in gastric cancer risk. METHODS: We selected age- and sex-stratified population samples in two areas with different gastric cancer incidence and mortality in Chile: Antofagasta (lower rate) and Valdivia (higher rate). Participants were 1-69 years old and provided interviews and blood for anti-H. pylori antibodies (IgG, VacA, CagA, others) and atrophy biomarkers (pepsinogens). RESULTS: H. pylori seroprevalence (Age-standardized to world population) and antibodies against CagA and VacA were similar in both sites. H. pylori seroprevalence was 20% among children <10 years old, 40% among 10-19 year olds, 60% in the 20-29 year olds and close to or above 80% in those 30+ years. The comparison of the prevalence of known and potential H. pylori cofactors in gastric carcinogenesis between the high and the low risk area showed that consumption of chili products was significantly higher in Valdivia and daily non-green vegetable consumption was more common in Antofagasta. Pepsinogen levels suggestive of gastric atrophy were significantly more common and occurred at earlier ages in Valdivia, the higher risk area. In a multivariate model combining both study sites, age, chili consumption and CagA were the main risk factors for gastric atrophy. CONCLUSIONS: The prevalence of H. pylori infection and its virulence factors was similar in the high and the low risk area, but atrophy was more common and occurred at younger ages in the higher risk area. Dietary factors could partly explain higher rates of atrophy and gastric cancer in Valdivia. IMPACT: The ENIGMA study in Chile contributes to better understanding regional variations in gastric cancer incidence and provides essential information for public health interventions.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Neoplasias Gástricas/etiologia , Estômago/patologia , Adolescente , Adulto , Idoso , Atrofia/etiologia , Atrofia/microbiologia , Atrofia/patologia , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estômago/microbiologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Adulto Jovem
10.
Trop Med Infect Dis ; 5(2)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545152

RESUMO

Q fever and rickettsial diseases occur throughout the world and appear to be emergent zoonoses in Chile. The diagnosis of these diseases is currently uncommon in Chile, as their clinical presentations are non-specific and appropriate diagnostic laboratory assays are of limited availability. During a recent outbreak of undiagnosed human atypical pneumonia, we serologically investigated a series of 357 cases from three regions of southern Chile. The aim was to identify those caused by Coxiella burnetii and/or Rickettsia spp. Serological analysis was performed by ELISA and an immunofluorescence assay (IFA) for acute and convalescence sera of patients. Our results, including data from two international reference laboratories, demonstrate that 71 (20%) of the cases were Q fever, and 44 (15%) were a likely rickettsial infection, although the rickettsial species could not be confirmed by serology. This study is the first report of endemic Q fever and rickettsial disease affecting humans in Chile.

16.
Vaccine ; 37(32): 4646-4650, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31266668

RESUMO

A National Immunization Technical Advisory Group (NITAG) provides independent, evidence-based recommendations to the Ministry of Health for immunization programmes and policy formulation. In this article, we describe the structure, functioning and work processes of Chile's NITAG (CAVEI) and assess its functionality, quality of work processes and outputs, and integration of the committee into the Ministry of Health policy process using the Assessment tool for National Immunization Technical Advisory Groups. Among its strengths, CAVEI's administrative and work plasticity allows it to respond in a timely manner to the Ministry of Health's requests and proactively raise subjects for review. Representation of multiple areas of expertise within the committee makes CAVEI a robust and balanced entity for the development of evidence-based comprehensive recommendations. High ranking profile of the Secretariat structure furthers CAVEI's competences in policymaking and serves as a bridge between the committee and international initiatives in the field of immunizations.


Assuntos
Comitês Consultivos/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Programas de Imunização/legislação & jurisprudência , Imunização/legislação & jurisprudência , Política Pública/legislação & jurisprudência , Vacinação/legislação & jurisprudência , Vacinas/normas , Chile , Tomada de Decisões , Humanos
17.
Environ Res ; 172: 578-585, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30875511

RESUMO

OBJECTIVE: Evaluate whether arsenic-related diabetes risks differ between people of low and high socioeconomic status (SES). METHODS: We used data collected between October 2007-December 2010 from a population-based cancer case-control study (N = 1301) in Northern Chile, an area with high arsenic water concentrations (>800 µg/L) and comprehensive records of past exposure. Information on lifetime exposure and potential confounders were obtained using structured interviews, questionnaires, and residential histories. Type 2 diabetes was defined as physician-diagnosed diabetes or oral hypoglycemic medication use. SES was measured using a 14-point scale based on ownership of household appliances, cars, internet access, or use of domestic help. Logistic regression was used to assess the relationship between arsenic and diabetes within strata of SES. RESULTS: Among those with low SES, the odds ratio (OR) for diabetes comparing individuals in the highest to lowest tertile of lifetime average arsenic exposure was 2.12 (95% confidence interval (CI) 1.29-3.49, p = 0.004). However, those in the high SES group were not at increased risk (OR = 1.12 [95% CI = 0.72-1.73]). CONCLUSIONS: Our findings provide evidence that risks of arsenic-related diabetes may be higher in Chile in people with low versus high SES.


Assuntos
Arsênio , Diabetes Mellitus Tipo 2 , Exposição Ambiental , Classe Social , Arsênio/efeitos adversos , Estudos de Casos e Controles , Chile/epidemiologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Fatores de Risco
18.
Hum Pathol ; 82: 87-94, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30036595

RESUMO

Gallbladder dysplasia can progress to cancer and may be associated with increased cancer risk at other biliary tract sites. Thus, its accurate identification is relevant both for etiologic understanding and for clinical purposes. Data on the frequency and distribution of gallbladder dysplasia are lacking owing to limited gallbladder sampling and inability to visualize dysplasia grossly. An expert pathology group used consensus criteria to review 140 totally sampled consecutive cholecystectomy specimens from Chilean women. Three cases (2%) revealed incidental invasive carcinoma, all T2, along with high-grade dysplasia (HGD). The surface areas covered by dysplasia or cancer in these cases were 9%, 37%, and 87%. Although the first longitudinal ("diagnostic") section of the whole gallbladder captured HGD or cancer in all 3 cases, the deepest focus of invasive carcinoma was not present in this section. Fourteen additional cases (10%) had low-grade dysplasia (LGD), which was typically very focal (covering <5% of the surface) and most often occurred in the fundus. LGD was not present in the diagnostic section of 5 cases (38%) and would have been missed without additional sampling. None of the cancers or dysplasias were grossly visible. Although HGD and carcinoma are likely to be identified in "diagnostic" sections, accurate staging requires total sampling. LGD is typically very focal and would often be missed in routine practice. To identify cancer precursors, additional sampling, particularly of the fundus, may be warranted. The predominance of LGD in the fundus also provides etiologic insight, supporting the contribution of gallstones and chronic inflammation.


Assuntos
Carcinoma/patologia , Neoplasias da Vesícula Biliar/patologia , Vesícula Biliar/patologia , Lesões Pré-Cancerosas/patologia , Adulto , Idoso , Biópsia , Carcinoma/epidemiologia , Carcinoma/cirurgia , Chile/epidemiologia , Colecistectomia , Feminino , Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/epidemiologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/cirurgia , Valor Preditivo dos Testes , Prevalência , Medição de Risco , Fatores de Risco
19.
Environ Res ; 167: 248-254, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30059859

RESUMO

BACKGROUND: The prevalence of type 2 diabetes (T2D) has nearly doubled since 1980. Elevated body mass index (BMI) is the leading risk factor for T2D, mediated by inflammation and oxidative stress. Arsenic shares similar pathogenic processes, and may contribute to hyperglycemia and ß-cell dysfunction. OBJECTIVES: We assessed a unique situation of individuals living in Northern Chile with data on lifetime arsenic exposure to evaluate the relationship between arsenic and T2D, and investigate possible interactions with BMI. METHODS: We analyzed data collected from October 2007-December 2010 from an arsenic-cancer case-control study. Information on self-reported weight, height, smoking, diet, and other factors were obtained. Diabetes was defined by self-reported physician-diagnoses or use of hypoglycemic medication. A total of 1053 individuals, 234 diabetics and 819 without known diabetes were included. RESULTS: The T2D odds ratio (OR) for cumulative arsenic exposures of 610-5279 and ≥ 5280 µg/L-years occurring 40 years or more before interview were 0.97 (95% CI: 0.66-1.43) and 1.53 (95% CI: 1.05-2.23), respectively. Arsenic-associated T2D ORs were greater in subjects with increased BMIs. For example, the ORs for past cumulative exposures ≥ 5280 µg/L-years was 1.45 (95% CI: 0.74-2.84) in participants with BMIs < 25 kg/m2 but 2.64 (95% CI: 1.14-6.11) in those with BMIs ≥ 30 kg/m2 (synergy index = 2.49, 95% CI: 0.87-7.09). Results were similar when people with cancer were excluded. CONCLUSIONS: These findings identify increased odds of T2D with arsenic exposure, which are significantly increased in individuals with excess BMI.


Assuntos
Arsênio/toxicidade , Diabetes Mellitus Tipo 2/epidemiologia , Obesidade/epidemiologia , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Chile , Diabetes Mellitus Tipo 2/induzido quimicamente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
20.
Toxicol Rep ; 5: 6-11, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29234604

RESUMO

Trace element composition in plant biomass could be used as an indicator of environmental stress, management practices and restoration success. A longitudinal study was conducted to compare Pb, Cd, and Cu content in seagrass Syringodium filiforme collected at a former bombing range in Puerto Rico with those of a Biosphere Reserve under similar geoclimatic conditions. Trace elements were measured by atomic absorption after dry-ashing of samples and extraction with acid. In general, levels of Pb, Cd, and Cu varied during 2001, 2003, 2005-2006, and 2013-2016. Results showed that bioaccumulated concentration of these trace elements were consistently higher, but not significant, at the bombing range site. As expected in polluted areas, greater variability in Pb and Cd content were observed in the military impacted site with levels up to 14 and 17 times higher than seagrass from the reference site, respectively. Although a decrease in Pb was observed after cessation of all military activities in 2003, the concentration in plant biomass was still above levels of ecological concern, indicating that natural attenuation is insufficient for cleanup of the site.

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