The Omicron wave in Mexico: vaccine protection against progression to severe Covid-19 in SARS-CoV-2-infected workers

OBJECTIVE

To assess the effectiveness of seven Covid-19 vaccines in preventing disease progression (DP) using data from national private sector workers during the Omicron wave in Mexico from January 2 to March 5, 2022.

MATERIALS AND METHODS

This study employed an administrative retrospective cohort design, analyzing DP (hospitalization or death due to respiratory disease) among workers who filed a respiratory short-term disability claim and tested positive for SARS-CoV-2. Risk ratios (RRadj) were estimated using Poisson regression models adjusted for various factors.

RESULTS

Vaccinated individuals had a lower risk of hospitalization and death compared with unvaccinated individuals. The overall RRadj for hospitalization and death were 0.36 (95%CI 0.32, 0.41) and 0.24 (0.17, 0.33), respectively. When evaluating vaccines individually, the RRadj for hospitalization were as follows Pfizer BioNTech 0.27 (95%CI 0.22, 0.33), Moderna 0.29 (95%CI 0.15, 0.57), Sinovac 0.32 (95%CI 0.25, 0.41), AstraZeneca 0.39 (95%CI 0.34, 0.46), Sputnik 0.39 (95%CI 0.28, 0.53), CanSino 0.41 (95%CI 0.24, 0.7), and Janssen 0.53 (95%CI 0.39, 0.72). The RRadj for death were as follows: Pfizer BioNTech 0.12 (95%CI 0.07, 0.19), Sputnik 0.15 (95%CI 0.06, 0.38), Sinovac 0.29 (95%CI 0.16, 0.53), AstraZeneca 0.30 (95%CI 0.20, 0.44), CanSino 0.38 (95%CI 0.1, 1.4), and Janssen 0.50 (95%CI 0.26, 0.97).

CONCLUSION

Covid-19 vaccines significantly reduced the risk of severe disease during the Omicron wave in Mexico.

SARS-CoV-2 seroprevalence and respiratory disease disability claims in Mexico City Metropolitan Area

OBJECTIVE

To characterize the impact of SARS-CoV-2 infection in workers from an essential large-scale company in the Greater Mexico City Metropolitan Area using point prevalence of acute infection, point prevalence of past infection through serum antibodies and respiratory disease short-term disability claims (RD-STDC).

MATERIALS AND METHODS

Four randomized surveys, three during 2020 before and one after (December 2021) vaccines' availability.

OUTCOMES

point prevalence of acute infection through saliva PCR (polymerase chain reaction) testing, point prevalence of past infection through serum antibodies against Covid-19, RD-STDC and prevalence of symptoms during the previous six months.

RESULTS

Prevalence of SARS-CoV-2 cases was 1.29-4.88%, on average, a quarter of participants pre-vaccination were seropositive; over half of participants with a RD-STDC had antibodies. The odds of having antibodies were 6-7 times more among workers with an RD-STDC.

CONCLUSIONS

High antibody levels against Covid-19 in this study population reflects that coverage is high among workers in this industry. STDCs are a useful tool to track workplace epidemics.

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. Five groups of participants were formed on the basis of the type of vaccine received and were divided on the basis of whether they previously had or did not have COVID-19. After completing the vaccination schedule, the seroprevalence was 95.5, 97.5, 81.0, 95.2, and 90.0% (BNT162b2, AZD1222, Convidecia, Sputnik V, and CoronaVac, respectively). Among the participants without COVID-19 prior to vaccination, the largest amount of antibodies in the 90-day period was observed in the BNT162b2 group, and the amount of antibodies in the Sputnik V group decreased the least over time. Even though the percentages of seroconversion obtained in this study were lower than those currently reported in other parts of the world, the tested vaccines are able, in most cases, to induce a good production of IgG antibodies anti-S1/S2 and neutralizing capacity. The fact that there are people who have not produced antibodies during the study leaves open some questions that must be investigated to avoid the appearance of serious cases of COVID-19. IMPORTANCE Since the start of the vaccination programs against COVID-19 in 2020, it was evident that due to global shortages, the demand for the dose required in Mexico could only be covered by acquiring different vaccines. Therefore, determining the effectiveness of these and the longevity of acquired immunity is extremely important in a scenario where SARS-CoV-2 circulation becomes endemic and booster doses are required periodically. Our data reveal significant differences both in the generation of antibodies as well as in their longevity for the vaccines applied in the country but suggest that, in general, the Mexican population can reach a high capacity to neutralize the virus, therefore, regarding less the variant for which they were designed.

Hacia el diseño de Vida Saludable, un nuevo programa de estudios para la educación básica en México

OBJETIVO

Describir el proceso de diseño de Vida Saludable, un nuevo programa de estudios para la educación básica en México. Material y métodos. Se conformó un equipo de trabajo entre especialistas en salud y la Secretaría de Educación Pública. Se establecieron las bases científicas de Vida Saludable, se seleccionaron y evaluaron materiales para Vida Saludable, y se revisaron contenidos vigentes de salud incluidos en otras asignaturas.

RESULTADOS

Alimentación, actividad física e higiene y limpieza fueron definidos como los tres ejes temáticos para Vida Saludable. Se aprobaron 3 de 228 insumos para usarse en Vida Saludable y 71.7% de los con-tenidos vigentes en educación básica sobre salud requieren ediciones.

CONCLUSIONES

Vida Saludable es un parteaguas hacia la alfabetización en materia de salud en educación básica en México, que se alinea con la agenda global para preservar la salud humana y planetaria.

[The estimated economic impact of cardiovascular and diabetes mellitus complications 2019-2028]

Background

In Mexico, diabetes mellitus (DM) and diseases cardiovascular, register an upward trend.

Objective

To estimate the number of complications due to cardiovascular events (CVD) and complications derived from DM (CDM) accumulated in beneficiaries of the Mexican Institute of Social Security (IMSS) from 2019 to 2028, as well as the expense for medical and economic benefits in a scenario baseline and one of change in metabolic profile due to lack of medical follow-up during the COVID-19 pandemic.

Material and methods

The number of CVD and CDM was estimated from 2019, with a 10-year risk projection using the ESC CVD Risk Calculator and United Kingdom Prospective Diabetes Study, considering risk factors registered in the institutional databases.

Results

From 2019 to 2028, cumulative CVD cases were estimated at 2 million and those of CDM in 960 thousand, with an impact on medical spending of 439,523 million pesos and on the economic benefits of 174,085 millions. When considering the COVID-19 pandemic, CVD events and CDM increased by 589 thousand, with an increase in spending of 93,787 million pesos for medical care and 41,159 million for economic benefits.

Conclusions

Without a comprehensive intervention in the management of CVD and CDM, the cost by both diseases will continue to increase, with financial pressures getting older.

Leading causes of excess mortality in Mexico during the COVID-19 pandemic 2020-2021: A death certificates study in a middle-income country

Background

The death toll after SARS-CoV-2 emergence includes deaths directly or indirectly associated with COVID-19. Mexico reported 325,415 excess deaths, 34.4% of them not directly related to COVID-19 in 2020. In this work, we aimed to analyse temporal changes in the distribution of the leading causes of mortality produced by COVID-19 pandemic in Mexico to understand excess mortality not directly related to the virus infection.

Methods

We did a longitudinal retrospective study of the leading causes of mortality and their variation with respect to cause-specific expected deaths in Mexico from January 2020 through December 2021 using death certificate information. We fitted a Poisson regression model to predict cause-specific mortality during the pandemic period, based on the 2015–2019 registered mortality. We estimated excess deaths as a weekly difference between expected and observed deaths and added up for the entire period. We expressed all-cause and cause-specific excess mortality as a percentage change with respect to predicted deaths by our model.

Findings

COVID-19 was the leading cause of death in 2020–2021 (439,582 deaths). All-cause total excess mortality was 600,590 deaths (38⋅2% [95% CI: 36·0 to 40·4] over expected). The largest increases in cause-specific mortality, occurred in diabetes (36·8% over expected), respiratory infections (33·3%), ischaemic heart diseases (32·5%) and hypertensive diseases (25·0%). The cause-groups that experienced significant decreases with respect to the expected pre-pandemic mortality were infectious and parasitic diseases (-20·8%), skin diseases (-17·5%), non-traffic related accidents (-16·7%) and malignant neoplasm (-5·3%).

Interpretation

Mortality from COVID-19 became the first cause of death in 2020–2021, the increase in other causes of death may be explained by changes in the health service utilization patterns caused by hospital conversion or fear of the population using them. Cause-misclassification cannot be ruled out.

Funding

This study was funded by Conacyt.

Plataforma CLIMSS como herramienta de alfabetización en salud durante la crisis sanitaria de Covid-19

Objetivo. Describir a la plataforma Cursos en Línea Masivos del IMSS (CLIMSS) como herramienta de alfabetización en salud, a través de la evaluación de la eficiencia terminal, la ganancia de competencias y satisfacción de los usuarios de cursos en línea masivos en el tema de Covid-19. Material y métodos. Se analizaron datos de 20 cursos ofertados entre marzo y octubre de 2020. Se evaluaron las calificaciones pre y pos, el número total de registros, el total de cursos terminados y la satisfacción del usuario. Resultados. Se registraron un total de 4.9 millones de usuarios y 10 millo­nes de inscripciones, en todos los estados de la República mexicana, con una eficiencia terminal de 85%, una ganancia de competencias de 30% y una satisfacción de 9.34 (10). Conclusiones. La plataforma CLIMSS ha mostrado ser una herramienta para la alfabetización en salud con un alcance de millones de mexicanos en temas relacionados con la crisis sanitaria Covid-19.  

Metodología de una encuesta por internet para hombres que tienen sexo con hombres en México

OBJETIVO

Describir el diseño, implementación y el perfil de los participantes de la Encuesta de Sexo Entre Hombres (ES Entre Hombres). Material y métodos. ES Entre Hombres es una encuesta en línea no probabilística aplicada a nivel nacional a hombres de 18 años o más, que tienen sexo con hombres (HSH) y que usan internet. La población de estudio se reclutó a través de publicidad en diversos sitios de encuentro en línea y los cuestionarios se autoaplicaron con SurveyGizmo.

RESULTADOS

Durante 11 semanas se registró un total de 15 875 autoaplicaciones elegibles y completas de las 32 entidades del país. La mayoría de los participantes fueron jóvenes (<29 años; 65.7%) y personas que acceden a internet diariamente (94.3%). Conclusión. Las encuestas realizadas por internet para poblaciones como los HSH representan un método costoefectivo de estudio poblacional, ya que tienen el potencial de ahorrar recursos y alcanzar muestras grandes, lo que a la vez facilita la cobertura geográfica a un bajo costo.

Epidemiology of sudden infant death syndrome in Mexico, 2005-2020

BACKGROUND

Sudden Infant Death Syndrome (SIDS) constitutes one of the main causes of mortality in children under one year of age in developed countries; it's frequency to varies geographically. In Mexico the real incidence of SIDS is not known.

METHODS

National databases of deaths in children under one year of age, from 2005 to 2020, were analyzed, due to Sudden Unexpected Infant Death (SUID) [SIDS (R95), accidental suffocation in a sleeping environment (W75), and other ill-defined and unspecified causes of mortality (R99), according to the International Classification of Diseases, tenth revision (ICD 10)]. Mortality rates per year of occurrence due to SUID and their subcategories were calculated. Simple frequencies of SIDS were obtained per year and month of occurrence, state of residence, age, place of death, and access to social security services.

RESULTS

In the study period 473,545 infant deaths occurred; 7,714 (1.62%) deaths were due to SUID; of these, 6,489 (84%) were due to SIDS, which is among the 10 leading causes of infant death in Mexico. The average mortality rate for SUID was 22.4/100,000 live births, for SIDS was 18.8/100,000 live births. Mortality rates within the states were variable, ranging from 2.4/100,000 to 105.1/100,000 live births. In 81% of SIDS records there was no autopsy; 38% of deaths due to SIDS occurred in infants under one month of age, up to 87% of deaths occurred in families without social security services or it was unknown, and 76.2% of deaths occurred at home. Deaths were more frequent during the last months of autumn and during winter.

CONCLUSION

In Mexico there is an underregistry of SIDS as cause of death, along with other SUID categories. Health workers need to be trained to improve diagnosis and data registration, including the practice of autopsies; additionally, it is necessary to implement a public health campaign.

Prevalence and predictors of elevated liver enzyme levels in Mexico: The Mexican National Health and Nutrition Survey, 2016

INTRODUCTION AND OBJECTIVE

To determine the prevalence of elevated liver enzyme levels and the fatty liver index according to specific sociodemographic, clinical, anthropometric, and metabolic risk factors in Mexican adult population.

MATERIAL AND METHODS

The present analysis was conducted using data from the Mexican National Health and Nutrition Survey 2016. For the present study, 3,490 adults with complete information on liver enzymes, sociodemographic, lifestyle, and metabolic factors were analyzed. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) levels were determined from blood samples. We computed the fatty liver Index (FLI), as a surrogate marker of non-alcoholic fatty liver disease. The associations are reported as adjusted odds ratios (OR) and 95% confidence intervals (95%CI).

RESULTS

At the national level, the prevalence of high serum levels of ALT, AST, and GGT were 7.9%, 13.5, and 12.9 respectively. We observed that men had higher prevalences of altered ALT, GGT and FLI compared to women. Additionally, we observe that individuals with obesity, metabolic syndrome and insulin resistance are significantly more likely to present elevated concentrations of AST, ALT, GGT and FLI. Finally, we found that the subjects of the lowest socioeconomic level and indigenous population were more likely to present elevated levels of AST, ALT, GGT, and FLI.

CONCLUSION

In Mexico, non-alcoholic fatty liver disease affect people with obesity, diabetes, and metabolic syndrome as well as men, subjects of low socioeconomic status, subjects who live in rural areas and indigenous population. Interventions to reduce this condition should be a public health priority.

Comportamiento epidemiológico de SARS-CoV-2 en población trabajadora afiliada al Instituto Mexicano del Seguro Social

Objetivo. Describir el comportamiento de la epidemia de SARS-CoV-2 entre los trabajadores afiliados al Instituto Mexicano del Seguro Social (IMSS). Material y métodos. Se analizaron las incapacidades temporales para el trabajo por enfermedades respiratorias (ITT-ER), las hospitalizaciones y defunciones asociadas durante el periodo del 1 marzo al 31 diciembre 2020. Se estimó la tasa de ataque (TA) por SARS-CoV-2, así como los riesgos relativos (RR) de ITT-ER, hos-pitalización y defunción. Resultados. De los trabajadores afiliados al IMSS, 8.8% (n=1 730 334) recibió al menos una ITT-ER. La TA fue mayor en mujeres y en ambos sexos fue menor en el grupo de >60 años. Los RR de hospitalización y defunción fueron mayores en hombres y aumentaron con la edad. Comparado con las ITT-ER de 2015-2019, Durango, Tamaulipas y Nuevo León tuvieron un RR mayor de ITT-ER que el resto del país. Conclusiones. La epidemia de SARS-CoV-2 tuvo repercusiones importantes en los trabajadores afiliados al IMSS; se observó un exceso de ITT-ER de 4.6 veces respecto a la frecuencia esperada y cerca de un millón de casos de SARS-CoV-2. Los datos sugieren que el sistema de ITT-ER puede ser utilizado como elemento adicional para la vigilancia epidemiológica de enfermedades emergentes.

[Massive canine and feline vaccination in Mexico: poor governance and market failure]

OBJECTIVE

To analyze decision-making concerning stewardship and procurement mechanisms in the context of the Program for Prevention and Control of Human Rabies and the National Canine and Feline Vaccination Week in Mexico.

MATERIALS AND METHODS

The information was obtained through requests to the National Institute of Transparency, Access to Information and Protection of Personal Data.

RESULTS

From 2009 to 2017, 158.9 million doses of canine rabies vaccine (VAR-CF) were applied with an estimated budget of 1 915 million pesos. Our findings suggest weak stewardship and ineffective governance that allows monopolistic practices and fragmented and direct purchases. Prices for the same product vary discretionally between states and are significantly higher than those offered at international level.

CONCLUSIONS

After 30 years of operation of the SNVA-C in Mexico, high prices of the VAR-CF persist, which are indicative of a significant market failure, characterized by zero competition, asymmetric information and misaligned incentive structures that precluded favorable price negotiation.

Trends in Mortality due to HIV/AIDS in children in Mexico: Towards the elimination of mother-tochild transmission

AIM OF THE STUDY

To examine mortality trends in children under 15 years of age due to HIV/AIDS in Mexico and describe their differences by insurance coverage.

METHODS

Time series analysis of deaths from 1990-2019 through a Bayesian poisson regression model with linear splines and knots in 1994, 1997, and 2003.

RESULTS

Overall, we observed a reduction in the mortality rate due to HIV from 2003 onwards, except in the group of 10-14 years. In the population covered with Social Security, mortality rates decreased in all age groups. However, in the group without Social Security or with Popular Security (subsidized system), mortality rates significantly decreased only for children below 5 years. of age.

CONCLUSIONS

Health insurance through the contributory system is associated with faster and larger reductions in HIV related infant mortality. Universal access to health insurance was not sufficient to close the gap in HIV-mortality among children under 15 years of age in Mexico.

Association between cumulative childhood blood lead exposure and hepatic steatosis in young Mexican adults

BACKGROUND

Exposure to environmental toxicants may play a role in the pathogenesis of Non Alcoholic Fatty Liver Disease (NAFLD). Cumulative exposure to lead (Pb) has chronic and permanent effects on liver function. Pediatric populations are vulnerable to the toxic effects of Pb, even at low exposure levels. The purpose of the study was to estimate the association between cumulative Pb exposure during childhood and hepatic steatosis biomarkers in young Mexican adults.

METHODS

A subsample of 93 participants from the ELEMENT cohort were included in this study. Childhood blood samples were collected annually from ages 1-4 years and were used to calculate the Cumulative Childhood Blood Lead Levels (CCBLL). Hepatic steatosis during adulthood was defined as an excessive accumulation of hepatic triglycerides (>5%) determined using Magnetic Resonance Imaging (MRI). Liver enzymes were also measured at this time, and elevated liver enzyme levels were defined as ALT (≥30 IU/L), AST (≥30 IU/L), and GGT (≥40 IU/L). Adjusted linear regression models were fit to examine the association between CCBLL (quartiles) and the hepatic steatosis in young adulthood.

RESULTS

In adulthood, the mean age was 21.4 years, 55% were male. The overall prevalence of hepatic steatosis by MRI was 19%. Elevate levels of the enzymes ALT, AST, and GGT were present in 25%, 15%, and 17% of the sample, respectively. We found a positive association between the highest quartile of CCBLL with the steatosis biomarkers of hepatic triglycerides (Q4 vs. Q1: β = 6.07, 95% CI: 1.91-10.21), elevated ALT (Q4 vs. Q1: β = 14.5, 95% CI: 1.39-27.61) and elevated AST (Q4 vs. Q1: β = 7.23, 95% CI: 0.64-13.82). No significant associations were found with GGT.

CONCLUSIONS

Chronic Pb exposure during early childhood is associated with a higher levels of hepatic steatosis biomarkers and hepatocellular injury in young adulthood. More actions should be taken to eliminate sources of Pb during the first years of life.

Criterios de retorno al trabajo y determinación del valor de vulnerabilidad por Covid-19

Objetivo. Establecer criterios médicos de retorno al trabajo en personal con riesgo de complicaciones por Covid-19. Material y métodos. Se realizó una revisión sistemática para identificar las condiciones y las características clínicas que influyen en el riesgo de desarrollar Covid-19 grave. Resultados. Se ha demostrado incremento del riesgo en obesidad, edad >60 años, diabetes mellitus, hipertensión arterial, enfermedad pulmonar obstructiva crónica, enfermedad cardiovascular, enfermedad renal crónica y cáncer. Solamente en diabetes se ha estudiado si el control previo influye. Se proponen condiciones específicas y el nivel de riesgo epidemiológico para el retorno al trabajo. Conclusiones. El retorno laboral de estos grupos debe priorizarse buscando favorecer el control de la enfermedad, identificando el estado de salud que incrementa el riesgo y protegiendo el derecho al trabajo. Se presentan recomendaciones para guiar la reincorporación al trabajo.

Overview of acute diarrheal disease at the dawn of the 21st century: The case of Mexico

OBJECTIVE

To provide an overview of morbidity and mortality due to acute diarrheal disease in Mexico in order to understand its magnitude, distribution, and evolution from 2000 to 2016.

MATERIALS AND METHODS

We carried out a longitudinal ecological study with secondary sources of information. We used data from epidemiological surveillance, health services, and vital statistics. We calculated and mapped measures of utilization of health services rates and mortality due to diarrheal diseases.

RESULTS

Diarrhea morbidity decreased by 42.1% across the period. However, emergency department attendances increased by 50.7% in the Ministry of Health. The hospitalization rate and mortality among the general population decreased by 37.6 and 39.7%, respectively, and the infant mortality rate decreased by 72.3% among children under five years of age. Chiapas and Oaxaca had the highest mortality among the states of Mexico.

CONCLUSIONS

Cases of diarrhea, including rotavirus, have decreased in Mexico. However, in 2016, 3.4 per 100 000 people died due to diarrhea, which could have been avoided with health promotion.

Cost-Effectiveness Of The Sugar-Sweetened Beverage Excise Tax In Mexico

An excise tax of 1 peso per liter on sugar-sweetened beverages was implemented in Mexico in 2014. We estimated the cost-effectiveness of this tax and an alternative tax scenario of 2 pesos per liter. We developed a cohort simulation model calibrated for Mexico to project the impact of the tax over ten years. The current tax is projected to prevent 239,900 cases of obesity, 39 percent of which would be among children. It could also prevent 61,340 cases of diabetes, lead to gains of 55,300 quality-adjusted life-years, and avert 5,840 disability-adjusted life-years. The tax is estimated to save $3.98 per dollar spent on its implementation. Doubling the tax to 2 pesos per liter would nearly double the cost savings and health impact. Countries with comparable conditions could benefit from implementing a similar tax.

[Subsample for the analysis of chronic diseases with biomarkers, National Survey of Health and Nutrition 2016]

OBJECTIVE

To describe the adult subsample for the analysis of biomarkers of chronic diseases, as well as the sample sizes (n) and representativity of the Encuesta Nacional de Salud y Nutrición (Ensanut) 2016.

MATERIALS AND METHODS

An adult subsample with national representativity was calculated to obtain blood, serum and urine samples. The prevalence of variables of interest was compared for each subsample.

RESULTS

The n for at least one serum biomarker and urine samples were 4 000 and 3 782, respectively. The n varied depending on the grouping of biomarkers and fasting time selection. No differences were observed in the distribution of variables between the whole sample, urine and blood biomarkers samples.

CONCLUSIONS

The weighted subsamples of urine, serum and blood biomarkers are comparable to the weighted sample of adults in the survey. The data of the subsample will allow to monitor the distribution of chronic diseases in Mexico, including altered function of liver and kidney, and sodium intake.

[Prevalence of diabetes and poor glycemic control in Mexico: results from Ensanut 2016.]

OBJECTIVE

To estimate the prevalence of total, diagnosed and undiagnosed diabetes, and the prevalence of poor glycemic control in Mexico, and its associated factors.

MATERIALS AND METHODS

Data from 3 700 adult participants were analysed in the 2016 National Health and Nutrition Survey. Diabetes prevalences were estimated with population weights, and the factors associated with total diabetes and poor glycemic control with Poisson regression models.

RESULTS

The total prevalence of diabetes was 13.7% (9.5% diagnosed, 4.1% undiagnosed); 68.2% of people with diagnosed diabetes presented poor glycemic control. Longer disease duration, living in the centre or south of the country and being treated in pharmacies were associated with poor glycemic control. Being treated in a social security system was associated with better glycemic control.

CONCLUSIONS

Multisectoral efforts are needed to strengthen screening, timely diagnosis and disease control, considering differences by region and type of health service.

Mexico: Lessons learned from the 2009 pandemic that help us fight COVID-19

In April 2009, Mexican, American, and Canadian authorities announced a novel influenza that became the first pandemic of the century. We report on lessons learned in Mexico. The Mexican Pandemic Influenza Preparedness and Response Plan, developed and implemented since 2005, was a decisive element for the early response. Major lessons-learned were the need for flexible plans that consider different scenarios; the need to continuously strengthen routine surveillance programs and laboratory capacity and strengthen coordination between epidemiological departments, clinicians, and laboratories; maintain strategic stockpiles; establish a fund for public health emergencies; and collaboration among neighboring countries. Mexico responded with immediate reporting and transparency, implemented aggressive control measures and generous sharing of data and samples. Lessons learned induced changes leading to a better response to public health critical events.

Overweight and obesity status from the prenatal period to adolescence and its association with non-alcoholic fatty liver disease in young adults: cohort study

OBJECTIVE

To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood.

DESIGN

Cohort study.

SETTING

ELEMENT Cohort in Mexico City.

POPULATION

Pregnant women with singleton births (n = 97).

METHODS

We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood.

MAIN OUTCOME

Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood.

RESULTS

Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (β = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (β = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status.

CONCLUSION

We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring.

TWEETABLE ABSTRACT

There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.

[Vaccination in Mexico: imprecise coverages and deficiency in the follow-up of children with incomplete immunization]

OBJECTIVE

To analyze the validity of the official vaccination figures according to the available information and to identify opportunities for improvement.

MATERIALS AND METHODS

We estimated vaccination coverage and dropout rates (for multi-dose vaccines) for one-year-old children, based on public information from the dynamic cubes of the Ministry of Health, for the years 2015 to 2017. R.

RESULTS

We observed variations in the vaccination monthly reports, which indicate low rates of vaccination, as well as high dropout rates when comparing first and third doses applied. For children 1 year of age, the national complete coverage was estimated at 48.9.

CONCLUSIONS

There is no reliable information to estimate the actual vaccination coverage. Government documents report a constant overestimation of vaccination coverage that creates a "false sense of security". This has become a barrier for the critical analysis of the Universal Vaccination Program.

Dyslipidemia prevalence, awareness, treatment and control in Mexico: results of the Ensanut 2012

OBJECTIVE

To describe in a national sample 1) the prevalence, awareness, treatment and control of dyslipidemias 2) the prevalence of dyslipidemias through previous national surveys.

MATERIALS AND METHODS

We analyzed data of the National Health and Nutrition Survey 2012, a representative cross-sectional study. Serum samples of 9 566 adults ≥20 years old with fasting ≥8 hours were analyzed for lipid fractions. Age-adjusted prevalences were calculated, by sociodemographic variables. Prevalence of awareness, treatment and control was estimated. A description of the dyslipidemia prevalence reported in previous surveys is reported.

RESULTS

Hypoalphalipoproteinemia and elevated LDL-C are the most prevalent dyslipidemias in Mexican adults. One in four adults had hypercholesterolemia at the moment of the interview without previous diagnosis. Awareness, treatment and control of dyslipidemia were 12.6, 3.7 and 3.1%, respec- tively.

CONCLUSIONS

Dyslipidemias are the most prevalent risk factor for cardiovascular diseases in Mexico. Public policies to increase awareness, access to therapy and sustained control are urgently needed.

Tobacco control in Mexico: a decade of progress and challenges

Mexico was the first country in the Americas to sign and ratify the World Health Organization's (WHO) Framework Convention on Tobacco Control (FCTC) in 2004. More than a decade later, it is appropriate to evaluate legislative and regulatory progress and the associated challenges; and also, to propose a roadmap to prioritize the problems to be addressed to achieve long-term sustainable solutions. Mexico has made substantial progress in tobacco control. However, regulations have been only weakly enforced. The tobacco industry continues to interfere with full implementation of the WHO-FCTC. As a result, tobacco consumption remains stable at about 17.6%, with a trend upwards among vulnerable groups: adolescents, women and low-income groups. The growing popularity of new tobacco products (electronic cigarettes or e-cigs) among young Mexicans is an increasing challenge. Our review reveals the need to implement all provisions of the WHO-FCTC in its full extent, and that laws and regulations will not be effective in decreasing the tobacco epidemic unless they are strictly enforced.

Diabetes is associated with a higher risk of mortality among women in a middle-income country: Results form the Mexican Teacher's cohort study

AIMS

In Mexico City, the mortality rate among patients with diabetes appears to be four times that of people without diabetes. Our study aimed to refine analyses of the impact of diabetes on mortality in a large cohort of women from different areas in Mexico with healthcare insurance.

METHODS

Our study followed 111,299 women with comprehensive healthcare coverage from the Mexican Teachers' Cohort. After a median follow-up of 7.8years, 5514 (5%) prevalent self-reported diabetes cases and 4023 incident cases were identified, while deaths were identified through employers' databases and next-of-kin reports, with dates and causes of death for 1121 women obtained from mortality databases. Hazard ratios (HRs) for total and cause-specific mortality were estimated by Cox regression models, using follow-up time as the time scale and allowing for time-variable diabetes status after adjusting for age, socioeconomic status, use of health services, and anthropometric and lifestyle variables.

RESULTS

In multivariable-adjusted models, the HR for all-cause mortality was 3.28 (95% CI: 2.86-3.75) in women with vs. without diabetes. The impact of diabetes on mortality was higher in rural vs. urban areas (HR: 4.72 vs. 2.98, respectively). HRs were 1.57 and 23.44 for cancer and renal disease mortality, respectively.

CONCLUSION

In women with healthcare coverage in Mexico, the magnitude of the association between diabetes and all-cause mortality was higher than that observed in high-income countries, but less than what has previously been reported for Mexico. Such elevated mortality suggests a lack of adequate access to quality diabetes care in the population despite comprehensive healthcare coverage.

[Assessing illicit drugs in wastewater: a pilot study in Mexico]

OBJECTIVE

Monitor drug use through wastewater metabolite measurement.

MATERIALS AND METHODS

Wastewater samples were obtained from 31 wastewater treatment plants and 95 sites with specific populations (38 schools, 42 units of addiction treatment and 15 penitentiaries). Using ultra high liquid chromatography, we measured nine metabolites from six drugs.

RESULTS

Eight out of nine drug metabolites were identified in the samples. Marijuana (THC-COOH), cocaine (benzoylecgonine) and methamphetamine were identified in schools, centers of addiction treatment and penitentiaries. Nuevo Laredo, Culiacan and Torreon had the highest consumption of cocaine, marijuana, amphetamine and methamphetamine.

CONCLUSIONS

Monitoring drug use through wastewater is feasible in Mexico and could constitute a surveillance system to identify changes in the time.

[Performance of medical schools in Mexico: results from the Examen Nacional para Aspirantes a Residencias Médicas]

OBJECTIVE

To assess the performance of medical schools (FEM) by analyzing the results of their applicants in the Examen Nacional para Aspirantes a Residencias Médicas (ENARM).

MATERIALS AND METHODS

Five performance criteria, two official and three created on purpose, were calculated from the ENARM-2016 and -2017 official databases to assess FEM performance.

RESULTS

In 2016 and 2017, applicants registered from 112 and 115 FEM, respectively. Depending on the performance criteria, the FEM in the first place obtained 5 to 20 points more than the one placed second, and 23 to 98 points more than the FEM in the last place. Approximately 25% applicants were classified as "knowledge-deficient," and about 80% of these originated from less than one third of the FEM.

CONCLUSIONS

The ENARM results provide information on the performance of the FEM. Approximately one of every four applicants obtained scores lower than the approval threshold of any specialty.

Necesidades de cobertura y atención del cáncer pulmonar en México

Objetivo. Analizar la cobertura en salud de cáncer pul­monar en México y ofrecer recomendaciones al respecto. Material y métodos. Mediante la conformación de un grupo multidisciplinario se analizó la carga de la enfermedad relativa al cáncer de pulmón y el acceso al tratamiento médico que ofrecen los diferentes subsistemas de salud en México. Resultados. Se documentan desigualdades importantes en la atención del cáncer de pulmón entre los distintos subsistemas de salud que sugieren acceso y cobertura en salud variable, tanto a los tratamientos tradicionales como a las innovaciones terapéuticas existentes, y diferencias en la capacidad de los prestadores de servicios de salud para garantizar el derecho a la protección de la salud sin distin­ciones. Conclusión. Se hacen recomendaciones sobre la necesidad de mejorar las acciones para el control del tabaco, el diagnóstico temprano y la inclusión de terapias innovadoras y la homologación entre los diferentes prestadores públicos de servicios de salud a través del financiamiento con la re­caudación de impuestos al tabaco

Flaws in the design of the Examen Nacional para Aspirantes a Residencias Médicas produce inequity

OBJECTIVE

To assess the assumption of 'equity' of Mexico's resident-selection assessment tool, the Examen Nacional para Aspirantes a Residencias Médicas (ENARM).

MATERIALS AND METHODS

Official ENARM-2016 and -2017 databases were analyzed. Differences in the absolute number of correct answers (multivariable linear regression) and the number of applicants reaching their specialty minimum score (SMS) per test day (odds ratio [OR]) were calculated. Applicants affected by test-day inequity were estimated.

RESULTS

There were 36 114 applicants in 2016, and 38 380 in 2017. In 2016, day-2 applicants had significantly higher scores and more reached the SMS than on days 1-3-4 (OR 1.55), and 5 (OR 3.8); 3 565 non-passing applicants were affected by inequity (equivalent to 44.64% of those selected). In 2017, day-1 and -2 applicants had significantly higher scores and more reached the SMS than on days 3-4 (OR 1.85), and 5 (OR 4.04); 3,155 non-passing applicants were affected by inequity (37.2% of those selected).

CONCLUSIONS

Analysis of official ENARM databases does not support the official attribution of equity, suggesting the test should be redesigned.

[A front-of-pack labelling system for food and beverages for Mexico: a strategy of healthy decision-making.]

The Mexican Ministry of Health requested the National Institute of Public Health to constitute a group of independent, free of conflict-of-interest academic experts on front-of-pack labelling (FOP). This group was instructed to created a positioning paper to contribute to the development of a FOP system for industrialized products that offers useful information for purchase decision making. This position paper uses the best available scientific evidence, and recommendations from experts of international organizations. The FOP proposal focuses on the contents of energy, nutrients, ingredients and components that if consumed in excess on the diet, can be harmful to people's health, such as added sugars, sodium, total fat, saturated fat and energy. The academic expert group recommends the implementation of a FOP that provides an easy way to quickly assess the quality of a product. It is essential that this FOP provides direct, simple, visible and easily understandable information.

The effect of a booster dose of HPV tetravalent vaccine after 51 months: implications for extended vaccination schedules

OBJECTIVE

To asses the non-inferiority between two differ- ent vaccination schedules one month after the administration of the third dose.

MATERIALS AND METHODS

We evaluated the anti-HPV 16/18 antibody titers induced by quadrivalent HPV vaccine administered using two different schedules in girls 9 to 10-year-old girls: a traditional (0-2-6) and an alterna- tive (0-6-50). Blood samples were collected at month 7, 21 and 51.

RESULTS

The antibody geometric mean titer ratios one month after the application of the third dose -month 51 for the alternative and month 7 for the traditional- were 1.55 for HPV16 (95%CI, 1.15-2.08) and 1.53 for HPV18 (95%CI, 1.12-2.09). The seropositive rate was above 99% in both groups.

CONCLUSIONS

The application of an alternative 3-dose schedule in 9 to 10-year-old girls induces a non-inferior immune response compared to the standard one month after the last dose. Further research is needed to understand the minimal number of doses and their timing to provide the best coverage for HPV infection.

Correction: Expected changes in obesity after reformulation to reduce added sugars in beverages: A modeling study

[This corrects the article DOI: 10.1371/journal.pmed.1002664.].

Persistence of Immunity When Using Different Human Papillomavirus Vaccination Schedules and Booster-Dose Effects 5 Years After Primary Vaccination

Background

There are limited data regarding the duration of immunity induced by different human papillomavirus (HPV) vaccination schedules and the immunogenicity of a booster dose of both bivalent HPV vaccine (bHPV) or quadrivalent HPV vaccine (qHPV).

Methods

Follow-up of a nonrandomized clinical trial to evaluate the 5-year antibody persistence of the bHPV in girls (age, 9-10 years) and women (age, 18-24 years). Noninferiority of the 2-dose versus 3-dose schedule among girls was evaluated at months 54 (n = 639) and 64 (n = 990). Girls vaccinated with a 2-dose schedule of bHPV or qHPV received a booster dose of either vaccine at month 61. Immunogenicity was measured using a virus-like particle-based enzyme-linked immunosorbent assay. Geometric mean titers (GMTs) for HPV16/18 were estimated after stratification by vaccination schedule and age group.

Results

At months 54 and 64, the 2-dose schedule remained noninferior to the 3-dose schedule. GMTs remained above natural infection levels across all age groups up to 64 months. After the booster, anti-HPV16/18 GMTs increased exponentially with the same pattern, regardless of vaccine administered. No safety concerns were identified with the booster dose.

Conclusions

A 2-dose schedule is highly immunogenic in girls, suggesting a high immune memory. Thus, a booster dose is likely to be unprofitable, considering the low global immunization coverage.

Clinical Trials Registration

NCT01717118.

The hidden burden of Chikungunya in central Mexico: results of a small-scale serosurvey

OBJECTIVE

To estimate the seroprevalence of CHKV antibodies and assess correlates of seropositivity at a small geographical scale.

MATERIALS AND METHODS

A community-based serosurvey of 387 households in Puente de Ixtla, Morelos (central Mexico). Serum IgG antibodies to CHKV were detected by immunoassay.

RESULTS

From 27 April to 29 May 2016, we interviewed and collected blood samples from 387 individuals at the same number of households. A total of 114 (29.5%) participants were seropositive to CHK, 36 (31.6%) of them reported no symptoms of CHKV infection within 12 months before the survey.

CONCLUSIONS

The estimated seroprevalence to CHKV antibodies was higher than expected by the small number of confirmed cases of CHKV infection reported in Mexico by the National Surveillance System.

Concentrations of nicotine, nitrosamines, and humectants in legal and illegal cigarettes in Mexico

BACKGROUND

Article 10 of the World Health Organization Framework Convention on Tobacco Control states the need for industry disclosure of tobacco contents and emissions. Currently, the profiles of key tobacco compounds in legal and illegal cigarettes are largely unknown. We aimed to analyze and compare concentrations of nicotine, nitrosamines, and humectants in legal and illegal cigarettes collected from a representative sample of smokers.

METHODS

Participants of the International Tobacco Control cohort provided a cigarette pack of the brand they smoked during the 2014 wave. Brands were classified as legal or illegal according to the Mexican legislation. Nicotine, nitrosamines, glycerol, propylene glycol, and pH were quantified in seven randomly selected packs of each brand. All analyses were done blinded to legality status. Average concentrations per brand and global averages for legal and illegal brands were calculated. Comparisons between legal and illegal brands were conducted using t tests.

RESULTS

Participants provided 76 different brands, from which 6.8% were illegal. Legal brands had higher nicotine (15.05 ± 1.89 mg/g vs 12.09 ± 2.69 mg/g; p < 0001), glycerol (12.98 ± 8.03 vs 2.93 ± 1.96 mg/g; p < 0.001), and N-nitrosanatabine (NAT) (1087.5 ± 127.0 vs 738.5 ± 338 ng/g; p = 0.006) concentrations compared to illegal brands. For all other compounds, legal and illegal brands had similar concentrations.

CONCLUSION

Compared to illegal cigarettes, legal brands seem to have higher concentrations of nicotine, NAT, and glycerol. Efforts must be made to implement and enforce Article 10 of the Framework Convention on Tobacco Control to provide transparent information to consumers, regulators, and policy-makers; and to limit cigarette engineering from the tobacco industry.

Expected changes in obesity after reformulation to reduce added sugars in beverages: A modeling study

BACKGROUND

Several strategies have been proposed to reduce the intake of added sugars in the population. In Mexico, a 10% sugar-sweetened beverages (SSBs) tax was implemented in 2014, and the implementation of other nutritional policies, such as product reformulation to reduce added sugars, is under discussion. WHO recommends that all individuals consume less than 10% of their total energy intake (TEI) from added sugars. We propose gradually reducing added sugars in SSBs to achieve an average 10% consumption of added sugars in the Mexican population over 10 years and to estimate the expected impact of reformulation in adult body weight and obesity.

METHODS AND FINDINGS

Baseline consumption for added sugars and SSBs, sex, age, socioeconomic status (SES), height, and weight for Mexican adults were obtained from the 2012 Mexico National Health and Nutrition Survey (ENSANUT). On average, 12.6% of the TEI was contributed by added sugars; we defined a 50% reduction in added sugars in SSBs over 10 years as a reformulation target. Using a dynamic weight change model, sugar reductions were translated into individual expected changes in body weight assuming a 43% caloric compensation and a 2-year lag for the full effect of reformulation to occur. Results were stratified by sex, age, and SES. Twelve years after reformulation, the TEI from added sugars is expected to decrease to 10%, assuming no compensation from added sugars; 44% of the population would still be above WHO recommendations, requiring further sugar reductions to food. Body weight could be reduced by 1.3 kg (95% CI -1.4 to -1.2) in the adult population, and obesity could decrease 3.9 percentage points (pp; -12.5% relative to baseline). Our sensitivity analyses suggest that the impact of the intervention could vary from 0.12 kg after 6 months to 1.52 kg in the long term.

CONCLUSIONS

Reformulation to reduce added sugars in SSBs could produce large reductions in sugar consumption and obesity in the Mexican adult population. This study is limited by the use of a single dietary recall and by data collected in all seasons except summer; still, these limitations should lead to conservative estimates of the reformulation effect. Reformulation success could depend on government enforcement and industry and consumer response, for which further research and evidence are needed.

[Methodological design of the National Health and Nutrition Survey 2016]

Objective:

Describe the design methodology of the halfway health and nutrition national survey (Ensanut-MC) 2016.

Materials and methods

The Ensanut-MC is a national probabilistic survey whose objective population are the inhabitants of private households in Mexico. The sample size was determined to make inferences on the urban and rural areas in four regions. Describes main design elements: target population, topics of study, sampling procedure, measurement procedure and logistics organization.

Results

A final sample of 9 479 completed household interviews, and a sample of 16 591 individual interviews. The response rate for households was 77.9%, and the response rate for individuals was 91.9%.

Conclusions

The Ensanut-MC probabilistic design allows valid statistical inferences about interest parameters for Mexico´s public health and nutrition, specifically on overweight, obesity and diabetes mellitus. Updated information also supports the monitoring, updating and formulation of new policies and priority programs.

Sobrepeso y obesidad en niños y adolescentes en México,actualización de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016

 Objetivo. Actualizar las prevalencias de sobrepeso y obe­sidad (SP+O) y estudiar algunos determinantes asociados en población<20 años, de la Encuesta Nacional de Salud y Nutrición de Medio Camino 2016 (Ensanut MC 2016). Ma­terial y métodos. La Ensanut MC 2016 es una encuesta nacional probabilística. Se estimó el puntaje Z del índice de masa corporal. Se clasificó el riesgo de sobrepeso, sobrepe­so y obesidad de acuerdo con el patrón de referencia de la OMS. Se estudiaron variables sociodemográficas asociadas con sobrepeso mediante regresión logística. Resultados. La prevalencia nacional de SP+O en <5 años fue niñas 5.8%, niños 6.5%; escolares niñas 32.8%, niños 33.7%; adolescentes mujeres 39.2% y hombres 33.5%. Las mujeres adolescentes de localidades rurales mostraron un incremento de 2012 a 2016 de 9.5 puntos porcentuales. Conclusiones. La prevalencia de SP+O en niñas y mujeres en zonas rurales muestran un aumento importante en un periodo corto, lo que llama a implementar acciones de atención inmediatas.

Zika virus infection estimates, Mexico

Objective

To assess the magnitude of the Mexican epidemic of Zika virus infection and the associated risk of microcephaly.

Methods

From the reported number of laboratory-confirmed symptomatic infections among pregnant women and the relevant birth rate, we estimated the number of symptomatic cases of infection that occurred in Mexico between 25 November 2015, when the first confirmed Mexican case was reported, and 20 August 2016. We used data from the birth certificates to compare mean monthly incidences of congenital microcephaly before (1 January 2010–30 November 2015) and after (1 December 2015–30 September 2017) the introduction of Zika virus, stratifying the data according to whether the mother’s place of residence was at an altitude of at least 2200 m above sea level. We used Poisson interrupted time series, statistical modelling and graphical analyses.

Findings

Our estimated number of symptomatic cases of infection that may have occurred in the general population of Mexico between 25 November 2015 and 20 August 2016, 60 172, was 7.3-fold higher than the corresponding number of reported cases. The monthly numbers of microcephaly cases per 100 000 live births were significantly higher after the introduction of the virus than before (incidence rate ratio, IRR: 2.9; 95% confidence interval, CI: 2.3 to 3.6), especially among the babies of women living at altitudes below 2200 m (IRR: 3.4; 95% CI: 2.9 to 3.9).

Conclusion

The Mexican epidemic appears to be much larger than indicated by estimates based solely on counts of laboratory-confirmed cases, and to be associated with significantly increased risk of microcephaly.

Uncovering neurodevelopmental windows of susceptibility to manganese exposure using dentine microspatial analyses

BACKGROUND

Associations between manganese (Mn) and neurodevelopment may depend on dose and exposure timing, but most studies cannot measure exposure variability over time well.

OBJECTIVE

We apply temporally informative tooth-matrix biomarkers to uncover windows of susceptibility in early life when Mn is associated with visual motor ability in childhood. We also explore effect modification by lead (Pb) and child sex.

METHODS

Participants were drawn from the ELEMENT (Early Life Exposures in MExico and NeuroToxicology) longitudinal birth cohort studies. We reconstructed dose and timing of prenatal and early postnatal Mn and Pb exposures for 138 children by analyzing deciduous teeth using laser ablation-inductively coupled plasma-mass spectrometry. Neurodevelopment was assessed between 6 and 16 years of age using the Wide Range Assessment of Visual Motor Abilities (WRAVMA). Mn associations with total WRAVMA scores and subscales were estimated with multivariable generalized additive mixed models. We examined Mn interactions with Pb and child sex in stratified models.

RESULTS

Levels of dentine Mn were highest in the second trimester and declined steeply over the prenatal period, with a slower rate of decline after birth. Mn was positively associated with visual spatial and total WRAVMA scores in the second trimester, among children with lower (< median) tooth Pb levels: one standard deviation (SD) increase in ln-transformed dentine Mn at 150 days before birth was associated with a 0.15 [95% CI: 0.04, 0.26] SD increase in total score. This positive association was not observed at high Pb levels. In contrast to the prenatal period, significant negative associations were found in the postnatal period from ~ 6 to 12 months of age, among boys only: one SD increase in ln-transformed dentine Mn was associated with a 0.11 [95% CI: - 0.001, - 0.22] to 0.16 [95% CI: - 0.04, - 0.28] SD decrease in visual spatial score.

CONCLUSIONS

Using tooth-matrix biomarkers with fine scale temporal profiles of exposure, we found discrete developmental windows in which Mn was associated with visual-spatial abilities. Our results suggest that Mn associations are driven in large part by exposure timing, with beneficial effects found for prenatal levels and toxic effects found for postnatal levels.

Consumption of foods and beverages in elementary schools: Results of the implementation of the general guidelines for foods and beverages sales in elementary schools in Mexico, stages II and III

The Mexican government developed the General Guidelines for the dispensing or distribution of foods and beverages at food sales in elementary schools (Guidelines). The objective is to evaluate the consumption of food and beverages during school hours, in two different stages of the implementation of the Guidelines: stages II (2011-2012) and stage III (2012-2013) in 565 elementary school students. We constructed three categories of consumption according to the origin of food: Home, food brought from home; School, food purchased at school and Both, food from home and food purchased at school. The main results showed that there are differences in both stages in energy intake according to the foods' origin; the category of School has the lowest energy and macronutrients consumption, as well as the closer compliance with de Guidelines recommendations in both stages, while the category of Both has a higher consumption and the less compliance with the Guidelines. This may be indicating an improvement in school guidelines and it is also reflecting the need to reinforce orientation for a healthy diet with respect to foods brought from home. It is necessary to continue with periodic evaluations to measure fulfillment with the Guidelines.

The Relationship of Socioeconomic Status with Body Mass Index Depends on the Socioeconomic Measure Used

OBJECTIVE

The association between socioeconomic status (SES) and body mass index (BMI) in middle-income countries is mixed. Heterogeneity in SES indicators used could explain some differences. This study aimed to identify SES indicators consistently associated with BMI in Mexican adults in 2006, 2012, and 2016.

METHODS

Data were obtained from the Mexican National Health and Nutrition Surveys of 2006, 2012, and 2016, including adults 20 to 59 years old. Given expected differences by sex, sex-stratified linear regression models were fitted for each survey. Age-adjusted and multivariate models were fit by using seven noncollinear SES indicators.

RESULTS

In age-adjusted models, most SES indicators were associated with a higher BMI in men; mixed associations were found for women. In multivariate models, living in urban areas was associated with a higher BMI for both men and women in 2006 and 2012. Across all surveys, education was associated with a lower BMI in women, while household assets were associated with a higher BMI in men.

CONCLUSIONS

The association between SES indicators and BMI is complex. Differences by sex need to be explicitly recognized when modeling this association. Approaches that rely on a single indicator could be confounded by other SES indicators. Adjusted models show the specific SES attributes that may influence BMI.

In utero exposure to DDT and incidence of diarrhea among boys from tropical Mexico

BACKGROUND

A higher incidence rate (IR) of acute gastrointestinal (GI) infections associated with prenatal exposure to p,p'-DDE was suggested by the results in two studies. Given the high mortality rate due to childhood diarrhea in some countries with ongoing use of DDT, additional data on this association is relevant for those making decisions about vector-borne disease control.

OBJECTIVE

To evaluate whether higher levels of prenatal exposure to p,p'-DDE and p,p'-DDT increase the risk of having diarrhea in a birth cohort of boys from tropical Mexico.

METHODS

Our analysis was based on 747 boys whose exposure was measured in maternal serum collected at delivery (2002-2003). Mothers reported the number of diarrhea episodes of their children during in-person interviews. The median age of the children at their last interview was 21.4 months. Poisson regression models were fitted to estimate adjusted incidence rate ratios (aIRR) of diarrhea by levels of p,p'-DDE and p,p'-DDT.

RESULTS

Overall, there were 1.7 episodes of diarrhea per child-year. Among those in the highest category of exposure (> 9µg DDE/g serum lipid), the aIRR for diarrhea was 1.14 (95% CI: 0.94, 1.30) compared to those in the lowest category of exposure (≤ 3µg/g). Among boys living in the urban area, the corresponding aIRR was 1.39 (95% CI: 1.07-1.80). Among rural boys, no associations emerged.

CONCLUSION

Although the results were consistent with a small positive association, the overall estimate was not precise. While urban boys in this study appeared to be more susceptible to DDE-associated diarrhea, a ready explanation for such increased susceptibility was not apparent.

Effect of care-delivery delay on the survival of Mexican women with breast cancer

OBJECTIVE

To estimate the effect of care-delivery delays on survival among women with breast cancer.

MATERIALS AND METHODS

A retrospective analysis of 854 women attending 11 hospitals from 2007-2009 was carried out. Kaplan-Meier estimators and a Cox proportional-risk model were employed.

RESULTS

A total of 10.5% of cases were diagnosed in stage I. 82% of sampled women delayed care for more than 67 days between noticing a symptom and initiating treatment. The median time from receipt of results of the mammography to biopsy was 31 days (IQR 14-56). Compared with those who were in quartile I (Q1), survival was lower among those in Q3 and Q4 (HR=1.68, 95%CI 0.94-3.00; HR=1.76, 95% CI 1.04-2.98, respectively).

CONCLUSIONS

To increase survival, it is suggested that the time between receipt of the mammography results and diagnostic biopsy be reduced.

Efecto del programa de servicios SaludArte en los componentes de alimentación y nutrición en escolares de la Ciudad de México

Objetivo. Evaluar el efecto del programa de servicios SaludArte en sus componentes de educación en nutrición y de asistencia alimentaria, dentro de escuelas participantes, durante 2013-2015. Material y métodos. Se realizó un estudio comparativo de tres cohortes que consideró 1 620 escolares de 144 primarias. Se construyeron dos paneles: de tiempo continuo y de tiempo completo. Se obtuvo información de consumo y hábitos alimenticios, higiene y conservación de alimentos, actividad física (AF) y antropometría. El análisis fue por diferencia en diferencias y modelos de regresión logística dicotómica y multinomial. Resultados. Los efectos atribuibles al programa fueron: higiene personal (p=0.045), conocimientos en nutrición (p=0.003), AF (p=0.002, 2013-2014; p=0.032, 2015) y consumo de fibra (p=0.064). El consumo de azúcar total fue significativo contrario a lo esperado (p=0.012, tiempo continuo; p=0.037, tiempo completo). Conclusiones. SaludArte tuvo efectos positivos en algunos componentes. Sin embargo, es necesario considerar las lecciones aprendidas, a fin de institucionalizar el programa y darle permanencia y crecimiento en las escuelas.

[Performance based regulation: a strategy to increase breastfeeding rates]

The decreasing breastfeeding rate in México is of public health concern. In this paper we discus an innovative regulatory approach -Performance Based Regulation- and its application to improve breastfeeding rates. This approach, forces industry to take responsibility for the lack of breastfeeding and its consequences. Failure to comply with this targets results in financial penalties. Applying performance based regulation as a strategy to improve breastfeeding is feasible because: the breastmilk substitutes market is an oligopoly, hence it is easy to identify the contribution of each market participant; the regulation's target population is clearly defined; it has a clear regulatory standard which can be easily evaluated, and sanctions to infringement can be defined under objective parameters.

RECOMMENDATIONS

modify public policy, celebrate concertation agreements with the industry, create persuasive sanctions, strengthen enforcement activities and coordinate every action with the International Code of Marketing of Breast-milk Substitutes.

[Lead poisoning and marginalization in newborns of Morelos, Mexico]

Objective:

To determine the prevalence of lead (Pb) poisoning at birth in Morelos, analyze its distribution by social marginalization level, and estimate the association with the use of lead glazed ceramics (LGC).

Materials and methods:

Blood lead level (BLL) in umbilical cord was measured in a representative sample of 300 randomly selected births at the Morelos Health Services and state IMSS.

Results:

The prevalence of Pb poisoning at birth (BLL> 5μg/dL) was 14.7% (95%CI: 11.1, 19.3) and 22.2% (95%CI: 14.4, 32.5) in the most socially marginalized municipalities. 57.1% (95%CI: 51.3, 62.7) of the mothers used LGC during pregnancy, and the frequency of use was significantly associated with BLL.

Conclusion:

This is the first study to document the proportion of newborns with Pb poisoning who are at risk of experiencing the related adverse effects. It is recommended to monitor BLL at birth and take action to reduce this exposure, especially in socially marginalized populations.

Legislación y salud pública en Francia

Señor editor: Sabemos que existen muchas maneras de proteger a nuestra población y, particularmente, a la población en mayor riesgo.