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Background:The development of vaccines to control the coronavirus disease 2019 (COVID-19) pandemic progression is a worldwide priority. CoronaVac is an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine approved for emergency use with robust efficacy and immunogenicity data reported in trials in China, Brazil, Indonesia, Turkey, and Chile.Methods:This study is a randomized, multicenter, and controlled phase 3 trial in healthy Chilean adults aged ≥18 years. Volunteers received two doses of CoronaVac separated by 2 (0–14 schedule) or 4 weeks (0–28 schedule); 2302 volunteers were enrolled, 440 were part of the immunogenicity arm, and blood samples were obtained at different times. Samples from a single center are reported. Humoral immune responses were evaluated by measuring the neutralizing capacities of circulating antibodies. Cellular immune responses were assessed by ELISPOT and flow cytometry. Correlation matrixes were performed to evaluate correlations in the data measured.Results:Both schedules exhibited robust neutralizing capacities with the response induced by the 0–28 schedule being better. No differences were found in the concentration of antibodies against the virus and different variants of concern (VOCs) between schedules. Stimulation of peripheral blood mononuclear cells (PBMCs) with Mega pools of Peptides (MPs) induced the secretion of interferon (IFN)-γ and the expression of activation induced markers in CD4+ T cells for both schedules. Correlation matrixes showed strong correlations between neutralizing antibodies and IFN-γ secretion.Conclusions:Immunization with CoronaVac in Chilean adults promotes robust cellular and humoral immune responses. The 0–28 schedule induced a stronger humoral immune response than the 0–14 schedule.Funding:Ministry of Health, Government of Chile, Confederation of Production and Commerce & Millennium Institute on Immunology and Immunotherapy, Chile.Clinical trial number:NCT04651790

IntroductionThe COmmunity Cohort Study aims to determine, after natural exposure to SARS-CoV-2 or anti-SARS-CoV-2 vaccines deployed in Chile to prevent COVID-19 in the context of the current pandemic, the strength and duration of detectable neutralising antibodies in adult ambulatory primary care patients with cardiovascular risk factors.Methods and analysisWe will set up a community-based longitudinal, prospective cohort study. The study will be conducted in two public outpatient clinics located in the southern district of Santiago, Chile. We expect to begin recruitment in the second quarter of 2022. Each patient will be followed up for at least 1 year after inclusion in the cohort. The eligible population will be adult patients registered in the Cardiovascular Health Programme. Exposure in this study is defined as any event where participants have contact with SARS-CoV-2 antigens from natural exposure or vaccination. The primary outcomes are seroconversion and strength and duration of the neutralising IgG antibodies to SARS-CoV-2. Secondary outcomes are any COVID-19-related event or intercurrent morbidities or death. Data will be collected by extracting serial blood samples and administering a questionnaire at the first face-to-face contact and monthly follow-up time points. The sample size estimated for this study is 1060. We will characterise the cohort, determine the seroprevalence rate of neutralising antibodies at baseline and determine the rates of antibody decline using a longitudinal mixed-effects model.Ethics and disseminationThe Scientific Ethics Committee of the South Metropolitan Health Care Service approved the study protocol (Memorandum No 191/2021). We will present the results in two peer-reviewed publications and national and international professional and academic meetings. We will organise seminars with relevant stakeholders and hold town hall meetings with the local community. We will set up a COmmunity Cohort Study website at www.communitystudy.cl to disseminate the study purpose, research team and milestones.

BackgroundCoronaVac®is an inactivated SARS-CoV-2 vaccine approved by the World Health Organization. Previous studies reported increased levels of neutralizing antibodies and specific T cells two- and four-weeks after two doses of CoronaVac®, but the levels of neutralizing antibodies are reduced at six to eight months after two doses. Here we report the effect of a booster dose of CoronaVac®on the anti-SARS-CoV-2 immune response generated against variants of concern (VOC) Delta and Omicron in adults participating in a phase 3 clinical trial in Chile.MethodsVolunteers immunized with two doses of CoronaVac®in a four-week interval received a booster dose of the same vaccine between twenty-four and thirty weeks after the 2nd dose. Four weeks after the booster dose, neutralizing antibodies and T cell responses were measured. Neutralization capacities and T cell activation against VOC Delta and Omicron were detected at four weeks after the booster dose.FindingsWe observed a significant increase in neutralizing antibodies at four weeks after the booster dose. We also observed an increase in CD4+T cells numbers over time, reaching a peak at four weeks after the booster dose. Furthermore, neutralizing antibodies and SARS-CoV-2 specific T cells induced by the booster showed activity against VOC Delta and Omicron.InterpretationOur results show that a booster dose of CoronaVac®increases the anti-SARS-CoV-2 humoral and cellular immune responses in adults. Immunity induced by a booster dose of CoronaVac®is active against VOC, suggesting an effective protection.

IntroductionQuality of reporting refers to how published articles communicate how the research was done and what was found. Gaps and imprecisions of reporting hamper the assessment of the methodological quality and internal and external validity. The CONsolidated Standards of Reporting Trials (CONSORT) are a set of evidence-based recommendations of the minimum elements to be included in the reporting of randomised controlled trials (RCTs) to ensure a complete and transparent account of what was done, how it was done and what was found. Few studies have been conducted on the impact of CONSORT on RCTs published in Latin American and Spanish journals. We aim to assess the reporting quality of RCTs of three clinical specialities published in Spanish and Latin American journals, as well as to assess changes over time and associations of quality with journal and country indicators.Methods and analysisWe will conduct a systematic survey of all RCTs published in Spanish-language journals in three clinical fields (dentistry, neurology and geriatrics) from 1990 to 2018. We will include RCTs from previous work that has identified all RCTs on these medical fields published in Spain and Latin America. We will update this work via handsearching of relevant journals. Assessment of quality of reporting will be conducted independently and in duplicate using the CONSORT 2010 Statement. We will also extract journal and country indicators. We will conduct descriptive statistics and secondary analyses considering the year, country, and journal of publication, among others.Ethics and disseminationThe Universidad de Santiago de Chile’s ethics committee approved the protocol. We will disseminate the results of this work in peer-reviewed scientific journals and conference proceedings. We expect to raise awareness among researchers, journal editors and funders on the importance of training in reporting guidelines and using them from the inception of RCT protocols.

IntroductionUniversity ranking systems and the publish-or-perish dictum, among other factors, are driving universities and researchers around the world to increase their research productivity. Authors frequently report multiple affiliations in published articles. It is not known if the reported institutional affiliations are real affiliations, which is when the universities have contributed substantially to the research conducted and to the published manuscript. This study aims to establish whether there is an empirical basis for author affiliation misrepresentation in authors with multiple institutional affiliations.Methods and analysisThis individual secondary data exploratory analysis on Scopus-indexed articles for 2016 will search all authors who report multiple institutional affiliations in which at least one of the affiliations is to a Chilean university. We will consider that misrepresentation of an affiliation is more likely when it is not possible to verify objectively a link between the author and the mentioned institution through institutional websites. If we cannot corroborate the author affiliation, we will consider this a finding of potential misrepresentation of the affiliation. We will summarise results with descriptive statistics.Ethics and disseminationThe study protocol was approved by the institutional ethics committee of Universidad de Santiago de Chile, Resolution No. 261, and dated January 15, 2018. Results will be submitted to the World Conference on Research Integrity, among other meetings on publication ethics and research integrity, and will be published in scientific, peer-reviewed journals.

Hepatitis A is an important public health problem in Chile. Childhood vaccination has reduced hepatitis A rates in several countries, prompting this evaluation of its cost-effectiveness in Chile. Using a Markov model, we project mass vaccination would reduce hepatitis A cases among birth cohort members and their personal contacts >80%. Vaccination costs of US$ 5.3–6.4 million would be offset by US$ 9.2–9.4 million reductions in disease costs. Further, approximately 70 fatal infections would be averted and >4600 quality-adjusted life years would be saved. This analysis supports the cost-effectiveness of universal childhood hepatitis A vaccination in Chile.

Rotavirus infections account every year in Chile, for approximately 53,000 emergency consultations and 8,000 hospital admissions among children under three years of age.To estimate incidence rates of severe rotavirus gastroenteritis in children3 years of age, living in the V and VIII Regions and to identify the predominant viral serotypes.A prospective hospital-based surveillance for severe gastroenteritis was implemented in public and private hospitals of Viña del Mar and Valparaiso (Region V) and of Chiguayante, Concepción, Penco, San Pedro de la Paz, Talcahuano and Tomé (Region VIII). All children3 years of age residing in the districts, who consulted for severe gastroenteritis requiring oral or intravenous rehydration (equivalent to WHO plan B or C), or who were admitted to the hospital, were enrolled. Demographic and clinical information and a stool sample were obtained. Rotavirus was detected by ELISA and positive samples were serotyped by ELISA or real time PCR.Between January 23 and June 30, 2003, a total of 760 children were recruited. Among these, 343 (45%) were admitted to the hospital. Stool samples were collected from 433 children. Among these, 214 were positive for rotavirus (49.4%). Overall, monthly disease incidence rates were 124/100,000 in V Region, and 114/100,000 in VIII Region. The predominant serotype was G4.Rotavirus was responsible for nearly half of the severe gastroenteritis episodes among children3 years, during a predominantly G4 serotype season. Every year, approximately one every 70 children3 years will have a severe rotavirus gastroenteritis episode.

Background: Rotavirus infections account every year in Chile, for approximately 53,000 emergency consultations and 8,000hospital admissions among children under three years of age. Aim: To estimate incidence rates of severe rotavirus gastroenteritis in children

Cost effectiveness studies are essential to assess the real value of interventions with preventive or therapeutic objectives.To assess the theoretical cost-effectiveness of a vaccine against rotavirus in Chilean children of less than five years of age.An economic model was developed based on information on disease incidence, health care costs associated with treatment and the effectiveness and costs of vaccination. Net disease and vaccination costs were estimated from the health system perspective and were compared with life years and disability-adjusted life-years (DALYs) gained using a 3% discount rate. Local administrative and accounting hospital data and vaccine efficacy data were used to estimate healthcare costs and cost-effectiveness of vaccination.A rotavirus vaccination program would prevent 10 deaths due to rotavirus gastroenteritis, 6,245 related hospitalizations and 41,962 outpatient visits during the first five years of life, per vaccinated cohort. For every 1,000 children born, the healthcare service spends US$15,077 on treatment of gastroenteritis. From the healthcare perspective, vaccination would yield a cost-effectiveness ratio of US$11,261 per DALY when the price of the vaccine is US$24 per course.Rotavirus vaccine can effectively reduce the disease burden and healthcare costs of rotavirus gastroenteritis and can be a cost-effective investment compared to other options.

Background:Cost effectiveness studies are essential to assess the real value of interventions with preventive or therapeutic objectives. Aim: To assess the theoretical cost-effectiveness of a vaccine against rotavirus in Chilean children of less than five years of age. Material and methods: An economic model was developed based on information on disease incidence, health care costs associated with treatment and the effectiveness and costs of vaccination. Net disease and vaccination costs were estimated from the health system perspective and were compared with life years and disability-adjusted life-years (DALYs) gained using a 3% discount rate. Local administrative and accounting hospital data and vaccine efficacy data were used to estimate healthcare costs and cost-effectiveness of vaccination. Results: A rotavirus vaccination program would prevent 10 deaths due to rotavirus gastroenteritis, 6,245 related hospitalizations and 41,962 outpatient visits during the first five years of life, per vaccinated cohort. For every 1,000 children born, the healthcare service spends US$15,077 on treatment of gastroenteritis. From the healthcare perspective, vaccination would yield a cost-effectiveness ratio of US$11,261 per DALY when the price of the vaccine is US$24 per course. Conclusions: Rotavirus vaccine can effectively reduce the disease burden and healthcare costs of rotavirus gastroenteritis and can be a cost-effective investment compared to other options