Epidemiologia

Background/Objectives: Cutaneous leishmaniasis (CL) remains a major public health and economic challenge in Morocco, where its transmission dynamics are increasingly influenced by climatic variability. This study aimed to evaluate the impact of meteorological factors on CL incidence in the province of Essaouira, a high-incidence region, to identify the environmental drivers behind recent epidemic trends. Methods: Epidemiological data (N = 834 cases) were collected from the Hygiene and Health Laboratory of Essaouira for the period between January 2014 and December 2023. Climatic variables were obtained from the Moroccan Directorate of National Meteorology. Data were analyzed at annual, seasonal, and monthly scales using the Spearman rank correlation in R 4.5.0 software to account for non-normal distributions and non-linear associations. Results: CL incidence remained stable from 2014 to 2021 before an unprecedented surge in cases during 2022–2023. Annual analysis indicated that warm and dry years pose a higher risk, with incidence positively correlated with temperatures and negatively associated with humidity and precipitation. Monthly results identified a biphasic regulatory mechanism: a winter hydric constraint phase with strong negative correlations with January rainfall and humidity (p < 0.05), followed by a summer thermal promotion phase where minimum temperature (T_min) emerged as the dominant driver (rho = 0.53), peaking in September (rho = 0.59). Conclusions: Our findings confirm the significant influence of climatic factors on CL incidence through complex seasonal dynamics. These results highlight the necessity of integrating high-resolution meteorological monitoring and predictive modeling into public health surveillance to anticipate future outbreaks in the context of increasing Mediterranean aridification.

Background/Objectives: Randomized controlled trials (RCTs) are the gold standard for evaluating treatment efficacy, yet recruitment and retention remain challenging, particularly when placebo arms are required. Using historical placebo data may reduce the need for contemporaneous placebo groups, but comparability between historical and real-time placebo responses is uncertain. This study assessed the feasibility of replacing a placebo control group with a historical placebo arm in osteoarthritis (OA) RCTs using several matching approaches. Methods: Data from three published knee OA RCTs (2009, 2013, 2017) were analyzed. The study followed three steps: (1) development of matching techniques using the 2009 and 2013 trials, (2) validation in the 2017 trial, and (3) post hoc analyses comparing placebo responses across trials. Methods included direct covariate adjustment, exact and nearest-neighbor matching, and propensity score matching based on baseline characteristics (age, sex, BMI, OA duration, baseline pain). The main outcome was change in 100 mm visual analogue scale (VAS) pain. Results: Initial attempts showed moderate to good success in adjusting historical placebo response on the VAS using various adjustment methods. However, in the validation process, a significant discrepancy was observed between real placebo VAS changes data and historical placebo VAS changes data, and various matching techniques failed to sufficiently reduce this discrepancy. In the post hoc analysis, despite the application of advanced matching techniques, substantial variability in VAS placebo responses persisted across trials. Even among placebo patients with highly similar baseline characteristics, the VAS changes over time differed significantly between studies. Conclusions: The findings indicate that replacing a real placebo group with a historical placebo in osteoarthritis RCTs is hardly feasible. These results underscore the complexity of placebo effects in osteoarthritis trials and the limitations of historical control data in this context.

The COVID-19 pandemic has significantly impacted public health in Mexico. Background/Objectives: This study evaluated its impact on the frequency of vaccine-preventable diseases (VPDs) from 2020 to 2024. Methods: The analyzed information was extracted from the weekly epidemiological bulletins, which compile the suspected, probable, and confirmed cases reported to the Ministry of Health. The epidemiological behavior of VPDs was analyzed with endemic channels based on 2014–2019 data. An endemic channel is a graphical tool that is used to plot a central tendency and its limits; with this tool we can detect the presence of an epidemic and quantify it. Between 2020 and 2024, VPDs presented variable patterns due to the pandemic. Results: Rotavirus cases exhibited an 81% negative deviation in 2020 and a final 47% negative deviation in comparison with the expected values from 2014–2019. Chickenpox declined by 91% in 2020, with a partial recovery in reports afterward. Hepatitis A and B declined initially, but hepatitis B surpassed pre-pandemic levels later. Mumps declined by 45% in 2020, with a partial recovery, remaining 35% below expected reports. Meningeal and pulmonary tuberculosis increased by 125% and 33%, respectively. Human Papilloma Virus (HPV) infection and mild cervical dysplasia showed negative deviations, with partial increases later. However, severe dysplasia and in situ cervical cancer reports exceeded expected levels. Conclusions: Overall, several VPDs showed negative deviations, which could increase the size of the susceptible population. In contrast, increases in tuberculosis and HPV infection present a major challenge for health systems, given their chronic and high treatment costs.