Assessing Vaccination Prioritization Strategies for COVID-19 in South Africa Based on Age-Specific Compartment Model.

The vaccines are considered to be important for the prevention and control of coronavirus disease 2019 (COVID-19). However, considering the limited vaccine supply within an extended period of time in many countries where COVID-19 vaccine booster shot are taken and new vaccines are developed to suppress the mutation of virus, designing an effective vaccination strategy is extremely important to reduce the number of deaths and infections. Then, the simulations were implemented to study the relative reduction in morbidity and mortality of vaccine allocation strategies by using the proposed model and actual South Africa's epidemiological data. Our results indicated that in light of South Africa's demographics, vaccinating older age groups (>60 years) largely reduced the cumulative deaths and the "0-20 first" strategy was the most effective way to reduce confirmed cases. In addition, "21-30 first" and "31-40 first" strategies have also had a positive effect. Partial vaccination resulted in lower numbers of infections and deaths under different control measures compared with full vaccination in low-income countries. In addition, we analyzed the sensitivity of daily testing volume and infection rate, which are critical to optimize vaccine allocation. However, comprehensive reduction in infections was mainly affected by the vaccine proportion of the target age group. An increase in the proportion of vaccines given priority to "0-20" groups always had a favorable effect, and the prioritizing vaccine allocation among the "60+" age group with 60% of the total amount of vaccine consistently resulted in the greatest reduction in deaths. Meanwhile, we observed a significant distinction in the effect of COVID-19 vaccine allocation policies under varying priority strategies on relative reductions in the effective reproduction number. Our results could help evaluate to control measures performance and the improvement of vaccine allocation strategy for COVID-19 epidemic.

Analyzing the COVID-19 vaccination behavior based on epidemic model with awareness-information.

BACKGROUND: The widespread use of effective COVID-19 vaccines could prevent substantial morbidity and mortality. Individual decision behavior about whether or not to be vaccinated plays an important role in achieving adequate vaccination coverage and herd immunity. METHODS: This research proposes a new susceptible-vaccinated-exposed-infected-recovered with awareness-information (SEIR/V-AI) model to study the interaction between vaccination and information dissemination. Information creation rate and information sensitivity are introduced to understand the individual decision behavior of COVID-19 vaccination. We then analyze the dynamical evolution of the system and validate the analysis by numerical simulation. RESULTS: The decision behavior of COVID-19 vaccination in China and the United States are analyzed. The results showed the coefficient of information creation and the information sensitivity affect vaccination behavior of individuals. CONCLUSIONS: The information-driven vaccination is an effective way to curb the COVID-19 spreading. Besides, to solve vaccine hesitancy and free-ride, the government needs to disseminate accurate information about vaccines safety to alleviate public concerns, and provide the widespread public educational campaigns and communication to guide individuals to act in group interests rather than self-interest and reduce the temptation to free-riding, which often results from individuals who are inadequately informed about vaccines and thus blindly imitate free-riding behavior.

Self-management Among Elderly Patients With Hypertension and Its Association With Individual and Social Environmental Factors in China.

BACKGROUND: The hypertension control rate in China is much lower than that in developed countries. Self-management among elderly patients with hypertension can improve blood pressure control; thus, it is necessary to explore its association with individual and social environmental factors. OBJECTIVE: Our objective was to investigate self-management among elderly patients with hypertension in China and its association with individual and social environmental factors based on the social ecological model. METHODS: A total of 301 elderly patients with hypertension were recruited to do a questionnaire survey based on the social ecological model, which included the General Demographic Information Questionnaire, Hypertension Patients Self-Management Behavior Rating Scale, World Health Organization Well-Being Index, Family APGAR Index, and Social Support Rating Scale. RESULTS: The lowest level of self-management behaviors was in exercise management, and the highest was in medication management. The results of multiple linear regression analysis showed that well-being, family function, sex, education level, and age were pivotal individual and social environmental factors influencing self-management behaviors among elderly patients with hypertension. CONCLUSIONS: There is a need to develop and test interventions that improve self-management in elderly patients with hypertension. Specifically, individualized interventions to promote exercise among elderly persons with hypertension who are single and living alone are needed. Male patients with a lower education level, poor well-being, poor family function, and the lowest self-management levels are a key population to target.

Association between dietary patterns during the third trimester and the risk of postpartum depression in China.

BACKGROUND: Postpartum depression, which has affected one in six women after giving birth, can exert detrimental effects on maternal, children and family well-being. This study investigated the association between dietary patterns and postpartum depression among Chinese women. METHODS: A total of 1659 participants were recruited and collected between July 2015 and June 2017 in Tianjin, China. The Chinese version of the Self-Rating Depression Scale was used to assess depressive symptoms at 6-12 weeks postpartum. Information about diet was obtained using an 81-item food frequency questionnaire. Logistic regression models were used to assess relationships between dietary patterns and the risk of postpartum depression. RESULTS: Six dietary patterns were identified by principal component analysis, including beverage, vegetable, cereal-meat, nut-fruit, egg and seafood patterns. The highest tertile (T3) of the nut-fruit pattern was significantly associated with a decreased risk of postpartum depression (OR: 0.740, 95% CI: 0.573-0.955, p = =0.020). Moreover, T3 of the seafood pattern was associated with a lower risk of postpartum depression than the lowest tertile (T1) of this pattern (OR: 0.753, 95% CI: 0.580-0.978, p = =0.033). No other associations were found. LIMITATIONS: A retrospective study. CONCLUSIONS: The nut-fruit pattern and seafood pattern were associated with a decreased risk of postpartum depression in Chinese women. The present findings reinforce the importance of an adequate diet of fruit, nuts, and seafood for postpartum women.

Effects of maternal folic acid supplementation during pregnancy on infant neurodevelopment at 1 month of age: a birth cohort study in China.

PURPOSE: This study aimed to explore effects of maternal folic acid (FA) supplementation during pregnancy on neurodevelopment in 1-month-old infants and to determine whether effects may be related to maternal circulating inflammatory cytokine concentrations. METHODS: This birth cohort study recruited 1186 mother-infant pairs in Tianjin, China, between July 2015 and July 2017. The women completed interviewer-administered questionnaires on their lifestyles and FA supplementation during pregnancy. Neurodevelopment was assessed in 1-month-old infants using a standard neuropsychological examination table. In 192 women, serum homocysteine (Hcy) and inflammatory cytokine concentrations were measured at 16-18 weeks of gestation. RESULTS: The infants whose mothers took FA supplements during pregnancy had a significantly higher development quotient (DQ) compared with those whose mothers were non-users (P < 0.05). After adjustment for maternal characteristics, supplementary FA use for 1-3 months, 3-6 months, and > 6 months were associated with the increases of 7.7, 11.0, and 7.4 units in the scale of infant DQ score compared with women reporting no supplement use, respectively (P < 0.05). FA supplementation was associated with a decreased serum concentration of Hcy (ß = [Formula: see text] 0.19), which was correlated with women's serum inflammatory cytokine concentrations at 16-18 weeks of gestation (ß = 0.57). Serum inflammatory cytokine concentrations were inversely related to DQ score in the 1-months-old offspring (ß = [Formula: see text] 0.22). CONCLUSIONS: Maternal FA supplementation during pregnancy favors neurodevelopment in the offspring at 1-month-old. This association may be mediated by changes in serum Hcy and inflammatory cytokine concentrations throughout pregnancy.

Well-being mediates the effects of social support and family function on self-management in elderly patients with hypertension.

Previous studies have linked self-management with social support and family function. However, little is known about the mechanisms underlying these relationships. This study aimed to explore the underlying relationships between social support (family function) and self-management and to examine whether well-being mediated these relationships in elderly patients with hypertension. A cross-sectional design was used to study 517 elderly patients with hypertension. Demographics, self-management behaviors, social support, family function and well-being were collected by questionnaires. Results showed that social support, family function and well-being were separately associated with self-management behaviors. When social support, family function and well-being were included in the regression model simultaneously, social support and family function were no longer the significant predictors of self-management, demonstrating mediation. Using bootstrapping approach, 89.9% of the relationship between social support and self-management was explained by well-being, and 66.3% of the relationship between family function and self-management was explained by well-being. Improving self-management in patients with hypertension should be a comprehensive approach which should take social support, family function and well-being into account. Health providers should realize the importance of focusing on the promotion of well-being, especially among elderly hypertensive patients with low social support and low family function.

Association between Duration of Folic Acid Supplementation during Pregnancy and Risk of Postpartum Depression.

Postpartum depression (PPD), as a common complication of childbearing, could have adverse consequences on mothers, children, and families. This cohort study aimed to assess the association between duration of folic acid (FA) supplementation during pregnancy and the onset of PPD in Chinese women. A total of 1592 participants were recruited, and data collected between July 2015 and March 2017 in Tianjin, China. Participants' baseline data were collected regarding socio-demographic and lifestyle characteristics, obstetric history, and FA supplementation during pregnancy. The Chinese version of the self-rating depression scale was used to assess depressive symptoms at 6-12 weeks postpartum, and the prevalence of PPD in participants was 29.4%. Pregnant women who took FA supplements for >6 months had a lower prevalence of PPD, compared to those who took FA for ≤6 months. After using the 1:1 ratio propensity score matching, 601 FA-users ≤ 6 months and 601 FA-users > 6 months were included in the further analyses; this also yielded similar results (P < 0.05). Logistic regression analysis showed that FA intake for >6 months was an independent determinant of PPD (odds ratio = 0.76; 95% confidence interval: 0.59-0.98; P < 0.05). Thus, prolonged FA supplementation during pregnancy was associated with a decreased risk of PPD in Chinese women.

[A study on clinical applications of the PAV ventilation].

This article analyses the principle of the PAV, researches into its clinical applications, estimates its merits and demerits, and discusses the new ventilation mode in contrast with the old ones.

[Clinical applications of noninvasive positive pressure mechanical ventilation technology].

This article expounds the types, applicable diseases and medical departments of noninvasive positive pressure mechanical ventilators and the problems we should pay attention to while using them.