A data-driven model for COVID-19 pandemic - Evolution of the attack rate and prognosis for Brazil.

We introduce a compartmental model SEIAHRV (Susceptible, Exposed, Infected, Asymptomatic, Hospitalized, Recovered, Vaccinated) with age structure for the spread of the SARAS-CoV virus. In order to model current different vaccines we use compartments for individuals vaccinated with one and two doses without vaccine failure and a compartment for vaccinated individual with vaccine failure. The model allows to consider any number of different vaccines with different efficacies and delays between doses. Contacts among age groups are modeled by a contact matrix and the contagion matrix is obtained from a probability of contagion p c per contact. The model uses known epidemiological parameters and the time dependent probability p c is obtained by fitting the model output to the series of deaths in each locality, and reflects non-pharmaceutical interventions. As a benchmark the output of the model is compared to two good quality serological surveys, and applied to study the evolution of the COVID-19 pandemic in the main Brazilian cities with a total population of more than one million. We also discuss with some detail the case of the city of Manaus which raised special attention due to a previous report of We also estimate the attack rate, the total proportion of cases (symptomatic and asymptomatic) with respect to the total population, for all Brazilian states since the beginning of the COVID-19 pandemic. We argue that the model present here is relevant to assessing present policies not only in Brazil but also in any place where good serological surveys are not available.

Depressive symptoms, self-esteem, HIV symptom management self-efficacy and self-compassion in people living with HIV.

The aims of this study were to examine differences in self-schemas between persons living with HIV/AIDS with and without depressive symptoms, and the degree to which these self-schemas predict depressive symptoms in this population. Self-schemas are beliefs about oneself and include self-esteem, HIV symptom management self-efficacy, and self-compassion. Beck's cognitive theory of depression guided the analysis of data from a sample of 1766 PLHIV from the USA and Puerto Rico. Sixty-five percent of the sample reported depressive symptoms. These symptoms were significantly (p ≤ 0.05), negatively correlated with age (r = -0.154), education (r = -0.106), work status (r = -0.132), income adequacy (r = -0.204, self-esteem (r = -0.617), HIV symptom self-efficacy (r = - 0.408), and self-kindness (r = - 0.284); they were significantly, positively correlated with gender (female/transgender) (r = 0.061), white or Hispanic race/ethnicity (r = 0.047) and self-judgment (r = 0.600). Fifty-one percent of the variance (F = 177.530 (df = 1524); p < 0.001) in depressive symptoms was predicted by the combination of age, education, work status, income adequacy, self-esteem, HIV symptom self-efficacy, and self-judgment. The strongest predictor of depressive symptoms was self-judgment. Results lend support to Beck's theory that those with negative self-schemas are more vulnerable to depression and suggest that clinicians should evaluate PLHIV for negative self-schemas. Tailored interventions for the treatment of depressive symptoms in PLHIV should be tested and future studies should evaluate whether alterations in negative self-schemas are the mechanism of action of these interventions and establish causality in the treatment of depressive symptoms in PLHIV.

Mediators of antiretroviral adherence: a multisite international study.

The purpose of this study was to investigate the effects of stressful life events (SLE) on medication adherence (3 days, 30 days) as mediated by sense of coherence (SOC), self-compassion (SCS), and engagement with the healthcare provider (eHCP) and whether this differed by international site. Data were obtained from a cross-sectional sample of 2082 HIV positive adults between September 2009 and January 2011 from sites in Canada, China, Namibia, Puerto Rico, Thailand, and US. Statistical tests to explore the effects of stressful life events on antiretroviral medication adherence included descriptive statistics, multivariate analysis of variance, analysis of variance with Bonferroni post-hoc analysis, and path analysis. An examination by international site of the relationships between SLE, SCS, SOC, and eHCP with adherence (3 days and 30 days) indicated these combined variables were related to adherence whether 3 days or 30 days to different degrees at the various sites. SLE, SCS, SOC, and eHCP were significant predictors of adherence past 3 days for the United States (p = < 0.001), Canada (p = 0.006), and Namibia (p = 0.019). The combined independent variables were significant predictors of adherence past 30 days only in the United States and Canada. Engagement with the provider was a significant correlate for antiretroviral adherence in most, but not all, of these countries. Thus, the importance of eHCP cannot be overstated. Nonetheless, our findings need to be accompanied by the caveat that research on variables of interest, while enriched by a sample obtained from international sites, may not have the same relationships in each country.