Intestinal parasites in Mexico are an endemic problem. A study was conducted in children, teenagers and adults in a rural community in Colima, Mexico to examine the prevalence and intensity of Ascaris lumbricoides infection and to evaluate the parasitological and clinical efficacy of nitazoxanide (NTZ). Two hundred and eighty children, teenagers and adults participated in this study. Parasitological diagnosis from faeces was confirmed by three consecutive stool samples using the floatation concentration Faust method. Egg counts were performed as described by the Kato–Katz technique before and after treatment. A questionnaire was systematically applied to obtain information about socio-economic status and hygienic habits. One hundred and six participants (38%) were diagnosed as harbouring intestinal parasites, and 86 of them (81%) were infected with A. lumbricoides. All patients with ascariasis infections underwent a complete physical examination before and after NTZ treatment. NTZ resolved 88% of the ascariasis cases, with a 89% clinical efficacy, and there was a 97.5% reduction in the levels of morbidity. The most intense infections for A. lumbricoides were found in housewives, and statistically significant associations were found between ascariasis and the absence of drainage and living in houses with dirt floors.

Maternal hypothalamic-pituitary-adrenal (HPA) axis disruption in pregnancy may contribute to the programming of childhood respiratory disease and may modify the effect of chemical toxins, like lead (Pb), on lung development. Child sex may further modify these effects. We sought to prospectively examine associations between maternal HPA axis disruption, prenatal Pb and childhood lung function and explore potential effect modification by maternal cortisol and child sex on the association between prenatal Pb and lung function outcomes. Analyses included 222 mothers and children enrolled in a longitudinal birth cohort study in Mexico City. Maternal diurnal salivary cortisol was assessed in pregnancy; cortisol awakening response (CAR) and diurnal slope were calculated. Blood Pb was measured during the second trimester of pregnancy. Post-bronchodilator lung function was tested at ages 8–11 years. Associations were modeled using generalized linear models with interaction terms, adjusting for covariates. A higher (flatter) diurnal slope was associated with lower FEV₁/FVC ratio (β: −0.433, 95%CI [−0.766, −0.101]). We did not find any main effect associations between prenatal Pb and lung function outcomes. We report an interaction between Pb and cortisol in relation to FEV₁/FVC and FEF_25–75% (p_interaction<0.05 for all). Higher prenatal Pb was associated with reduced FEV₁/FVC only in children whose mothers had a high CAR. Higher prenatal Pb was also associated with reduced FEV₁/FVC and FEF_25–75% in mothers with a flatter diurnal slope. A 3-way interaction between prenatal Pb, CAR and sex on FEV₁/FVC, indicated that boys born to women with high CAR and higher prenatal Pb levels had lower FEV₁/FVC ratios (p_interaction=0.067). Associations between prenatal Pb and childhood lung function were modified by disrupted maternal cortisol in pregnancy and child sex. These findings underscore the need to consider complex interactions to fully elucidate effects of prenatal Pb exposure on childhood lung function.

The aim of this study was to examine changes in depression, stress and social support levels before and during the COVID-19 pandemic in women living in Mexico City. We studied 466 women enrolled in the Programming Research in Obesity, Growth, Environment and Social Stressors (PROGRESS) study who completed the Edinburgh Depression Scale (EDS) questionnaire prior (2018–2019) and during the lockdown period of the pandemic (May–November 2020). Psychosocial stress and social support for both time periods were ascertained using the Crisis in Family Systems (CRISYS) questionnaire and the Social Support Network (SSN) Scale, respectively. Associations between stress, social support and change in EDS score/depression were analyzed using generalized linear models adjusting for covariates. Higher stress (>median) during the pandemic was associated with an increase in EDS score (β: 2.13; 95% CI (1.06, 3.19), p < 0.001), and higher odds of depression (OR: 3.75; 95% CI (2.17, 6.50), p < 0.001), while social support was associated with lower odds of depression (OR: 0.56, 95% CI (0.32, 0.97), p = 0.037). Higher levels of stress during the pandemic were associated with depression. Social support may act as a buffer for the effects of psychosocial stress. Future studies should examine the long-term effects of stress associated with the pandemic on mental and overall health.

Background: The link between prenatal exposure to metal(loid)s and childhood lung function, including sex-specific effects, has not been completely elucidated. We aimed to examine sex-specific individual and joint effects of prenatal metal(loid)s exposure on children’s lung function. Methods: Analyses included 438 mother-child dyads from the Programming Research in Obesity, Growth, Environment, and Social Stressors birth cohort in Mexico City. Metal(loid)s levels (As, Cd, Co, Cu, Mn, Ni, Pb, Se, and Zn) were measured in maternal blood collected during the second and third trimesters. Lung function in children was assessed once at ages 8–14 years. Multiple linear regression was performed to evaluate individual associations. Mixture effects were assessed through repeated holdout weighted quantile sum regression and hierarchical Bayesian kernel machine regression. Effect modification by sex was examined. Results: Second-trimester Ni was inversely associated with FEV ₁ /FVC ratio in the overall sample and in females, while Pb was linked to lower FEV ₁ z-score in females. Third-trimester Co and Pb were also negatively associated with FVC z-score in females, with Pb also associated with lower FEV ₁ z-score in females. Higher metal mixture concentrations were associated with lower FEV ₁ /FVC ratio (β = −0.33, 95% confidence interval: −0.48, −0.16) and FEF _25%–75% z-score (β = −0.22, 95% confidence interval: −0.39, −0.07) in females, with similar sex-specific patterns of association in weighted quantile sum and Bayesian kernel machine regression models. Conclusions: Second-trimester metal mixture exposure is associated with lower childhood lung function; females are potentially more susceptible to these exposures, which underscores the need to understand critical windows of exposure and sex-specific differences.

Environmental Health Perspectives is an Open Access journal published by the National Institute of Environmental Health Sciences. Environmental Health Perspectives is an Open Access journal published by the National Institute of Environmental Health Sciences.