Impact of vaccination on infection or death from COVID-19 in individuals with laboratory-confirmed cases: Case-control study.

Objectives: The objective of this study is to estimate the effectiveness of COVID-19 vaccines in people treated within the social security system whose vaccination status was reported to the epidemiological surveillance system.

Study Design: Case-control study.

Methods: This was a case-control study conducted.

Diversity, composition, and networking of saliva microbiota distinguish the severity of COVID-19 episodes as revealed by an analysis of 16S rRNA variable V1-V3 region sequences.

Studies on the role of the oral microbiome in SARS-CoV-2 infection and severity of the disease are limited. We aimed to characterize the bacterial communities present in the saliva of patients with varied COVID-19 severity to learn if there are differences in the characteristics of the microbiome among the clinical groups. We included 31 asymptomatic subjects with no previous COVID-19 infection or vaccination; 176 patients with mild respiratory symptoms, positive or negative for SARS-CoV-2 infection; 57 patients that required hospitalization because of severe COVID-19 with oxygen saturation below 92%, and 18 fatal cases of COVID-19.

Predict the incidence of Guillain Barré Syndrome and arbovirus infection in Mexico, 2014-2019.

The Dengue (DENV), Zika (ZIKV), and Chikungunya (CHIKV) virus infections have been linked to Guillain-Barré syndrome (GBS). GBS has an estimated lethality of 4% to 8%, even with effective treatment. Mexico is considered a hyperendemic country for DENV due to the circulation of four serotypes, and the ZIKV and CHIKV viruses have also been circulating in the country.

Longevity and Neutralizing Capacity of IgG Antibodies against SARS-CoV-2 Generated by the Application of BNT162b2, AZD1222, Convidecia, Sputnik V, and CoronaVac Vaccines: a Cohort Study in the Mexican Population.

The WHO has approved the use of several vaccines during the COVID-19 pandemic; experience over the last 2 years has indicated that dose demand can only be covered using more than one design. Therefore, having scientific evidence of the performance of the different vaccines applied in a country is highly relevant. In Mexico, 5 vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were used, allowing a cohort study to analyze the generation of anti-S1/S2 IgG antibodies and anti-RBD antibodies with neutralizing activity at 0, 21, 90, and 180 days after vaccination.

Metagenomic analysis reveals differences in the co-occurrence and abundance of viral species in SARS-CoV-2 patients with different severity of disease.

Background: SARS-CoV-2 infections have a wide spectrum of clinical manifestations whose causes are not completely understood. Some human conditions predispose to severe outcome, like old age or the presence of comorbidities, but many other facets, including coinfections with other viruses, remain poorly characterized.

Methods: In this study, the eukaryotic fraction of the respiratory virome of 120 COVID-19 patients was characterized through whole metagenomic sequencing.

Efficacy and Safety of Vitamin D Supplementation to Prevent COVID-19 in Frontline Healthcare Workers. A Randomized Clinical Trial.

Background: Associations between vitamin D (VD) deficiency and the risk of SARS-CoV-2 infection have been documented in cross-sectional population studies. Intervention studies in patients with moderate to severe COVID-19 have failed to consistently document a beneficial effect.

Objective: To determine the efficacy and safety of VD-supplementation in the prevention of SARS-CoV-2 infection in highly exposed individuals.

[Coinfections by SARS-CoV-2 and other respiratory viruses and their clinical outcome].

Background: SARS-CoV-2 is a coronavirus described for the first time in China, in December 2019. This virus can cause a disease with a very variable spectrum that ranges from asymptomatic cases to deaths. The most severe cases are normally associated with comorbidities and with the age of the patient.

Impact of the introduction of chikungunya and zika viruses on the incidence of dengue in endemic zones of Mexico.

Background: With the arrival of chikungunya (CHIKV) and zika (ZIKV) viruses in Mexico, there was a decrease in diagnosed dengue virus (DENV) cases. During the first years of cocirculation (2015-2017), the algorithms established by epidemiological surveillance systems and the installed capacity limited us to one diagnostic test per sample, so there was an underestimation of cases until September 2017, when a multiplex algorithm was implemented. Therefore, the objective of this study was determine the impact of the introduction of CHIKV and ZIKV on the incidence of diagnosed DENV in endemic areas of Mexico, when performing the rediagnosis, using the multiplex algorithm, in samples from the first three years of co-circulation of these arboviruses.

Genetic Analysis of SARS-CoV-2 Variants in Mexico during the First Year of the COVID-19 Pandemic.

During the first year of the SARS-CoV-2 pandemic in Mexico, more than two million people were infected. In this study, we analyzed full genome sequences from 27 February 2020 to 28 February 2021 to characterize the geographical and temporal distribution of SARS-CoV-2 lineages and identify the most common circulating lineages during this period. We defined six different geographical regions with particular dynamics of lineage circulation.

Antibacterial effect of acetic acid during an outbreak of carbapenem-resistant Acinetobacter baumannii in an ICU (II).

Introduction: Acetic acid (AA) has been commonly used in medicine as an antiseptic agent for the past 6000 years. This study evaluated the antibacterial effect of AA during an outbreak in an intensive care unit (ICU) facility in Baja California Sur, México.

Methodology: Thirty-five environmental samples were collected, subsequently, disinfection with AA (4%) was performed, and two days later the same areas were sampled inside the ICU facility.

SARS-CoV-2 IgG Antibodies Seroprevalence and Sera Neutralizing Activity in MEXICO: A National Cross-Sectional Study during 2020.

Until recently, the incidence of COVID-19 was primarily estimated using molecular diagnostic methods. However, the number of cases is vastly underreported using these methods. Seroprevalence studies estimate cumulative infection incidences and allow monitoring of transmission dynamics, and the presence of neutralizing antibodies in the population.

Zika and dengue but not chikungunya are associated with Guillain-Barré syndrome in Mexico: A case-control study.

Background Zika, dengue and chikungunya viruses (ZIKV, CHIKV and DENV) are temporally associated with neurological diseases, such as Guillain-Barré syndrome (GBS). Because these three arboviruses coexist in Mexico, the frequency and severity of GBS could theoretically increase. This study aims to determine the association between these arboviruses and GBS in a Mexican population and to establish the clinical characteristics of the patients, including the severity of the infection.

Zika Virus infection and Guillain-Barré syndrome in Northeastern Mexico: A case-control study.

Background: Beginning August 2017, we conducted a prospective case-control investigation in Monterrey, Mexico to assess the association between Zika virus (ZIKV) and Guillain-Barré syndrome (GBS).

Methods: For each of 50 GBS case-patients, we enrolled 2-3 afebrile controls (141 controls in total) matched by sex, age group, and presentation to same hospital within 7 days.

Results: PCR results for ZIKV in blood and/or urine were available on all subjects; serum ZIKV IgM antibody for 52% of case-patients and 80% of controls.

Zika virus: Epidemiological surveillance of the Mexican Institute of Social Security.

Introduction: At the end of 2015, the first cases of Zika were identified in southern Mexico. During 2016, Zika spread as an outbreak to a large part of the country's coastal zones.

Methodology: The Zika epidemiological surveillance system records cases with clinical symptoms of Zika virus disease (ZVD) and those confirmed by means of a reverse polymerase chain reaction (RT-PCR) assay.

Association of Notified Cases and Treatment Success Rates in Pulmonary Tuberculosis.

Background: Tuberculosis has long been recognized as a public health problem in large cities. The goals of the "Stop TB" strategy of the WHO specifically promote its study at the subnational level. Therefore, we aimed to describe the state of pulmonary tuberculosis (PTB) at the municipality level in Mexico.

Association of Pulmonary Tuberculosis and HIV in the Mexican Institute of Social Security, 2006-2014.

Background: Tuberculosis and HIV remain a public health problem in developed countries. The objective of this study was to analyze the incidence trends of pulmonary TB and HIV comorbidity and treatment outcomes according to HIV during the period 2006 to 2014 in the Mexican Institute of Social Security.

Methods: Analyzed data from this registry including pulmonary tuberculosis patients aged 15 years and older who had been diagnosed during the years 2006 to 2014 in the Mexican Institute of Social Security.

[Technical guidelines for the prevention, diagnosis and treatment of Zika virus infection].

Infection Zika virus is an emerging disease in the Americas region, which is caused by Zika virus (ZIKV), an arbovirus of the flavivirus genus. The ZIKV is transmitted by the bite of Aedes mosquitoes, both in urban and jungle area. After the mosquito bite, the disease symptoms usually appear after an incubation period of three to twelve days.

[Microorganisms responsible of nosocomial infections in the Mexican Social Security Institute].

Background: The prevention and control of the nosocomial infections involve the knowledge of the most frequent type of microorganism isolated. In Mexico there are not national statistics to identify the main microorganisms that cause a nosocomial infection.

Methods: It was conducted an analysis of all the culture results of the nosocomial infections reported by the Sistema de Vigilancia Epidemiológica Hospitalaria (Epidemiological Surveillance System) of the Instituto Mexicano del Seguro Social during the year 2013.

[Epidemiological surveillance of febrile rash illness].

Background: Three imported cases of measles were detected in 2011, so the issue of surveillance with epidemiological alerts intensified. The aim of this article is to describe the phenomenon of intensified surveillance of febrile rash illness before the import of confirmed measles in the country at the Mexican Institute of Social Security cases.

Methods: The cases of epidemiological surveillance system 2011 were obtained was compared with the prior year It was determined t-Student mean difference and Wilson test for proportions, both with an alpha value of 0.

[Pertussis in Mexico, an epidemiological overview. A study of 19 years at the Instituto Mexicano del Seguro Social].

Background: Bordetella pertussis infection remains a public health problem in several developed and developing we describe the epidemiological syndrome cases subsystem special surveillance of whooping cough from 1992 to 2011 at a population with social security.

Methods: We obtained special cases subsystem Pertussis surveillance of 1992-2011. Univariate analysis was made of rates, ratios and proportions.

[Technical guidelines for the prevention and treatment of chikungunya fever].

Chikungunya fever is an emerging disease caused by an alphavirus belonging to the Togaviridae family, transmitted by the bite of Aedes genus species: Aedesaegypti and Aedesalbopictus. In 2013, PAHO/WHO received confirmation of the first cases of indigenous transmission of chikungunya in the Americas. This disease may be acute, subacute and chronic, affecting all age groups.