The influence of gender and temephos exposure on community participation in dengue prevention: a compartmental mathematical model.

BACKGROUND: The use of temephos, the most common intervention for the chemical control of Aedes aegypti over the last half century, has disappointing results in control of the infection. The footprint of Aedes and the diseases it carries have spread relentlessly despite massive volumes of temephos. Recent advances in community participation show this might be more effective and sustainable for the control of the dengue vector. METHODS: Using data from the Camino Verde cluster randomized controlled trial, a compartmental mathematical model examines the dynamics of dengue infection with different levels of community participation, taking account of gender of respondent and exposure to temephos. RESULTS: Simulation of dengue endemicity showed community participation affected the basic reproductive number of infected people. The greatest short-term effect, in terms of people infected with the virus, was the combination of temephos intervention and community participation. There was no evidence of a protective effect of temephos 220 days after the onset of the spread of dengue. CONCLUSIONS: Male responses about community participation did not significantly affect modelled numbers of infected people and infectious mosquitoes. Our model suggests that, in the long term, community participation alone may have the best results. Adding temephos to community participation does not improve the effect of community participation alone.

Utility of a Pulmonary Oedema Score for Predicting the Need for Mechanical Ventilation in COVID-19 Patients in a General Hospital.

BACKGROUND: The Radiographic Assessment of Lung Edema (RALE) score has been used to estimate the extent of pulmonary damage in patients with acute respiratory distress syndrome and might be useful in patients with COVID-19. AIM OF THE STUDY: To examine factors associated with the need for mechanical ventilation in hospitalized patients with a clinical diagnosis of COVID-19, and to estimate the predictive value of the RALE score. METHODS: In a series of patients admitted between April 14 and August 28, 2020, with a clinical diagnosis of COVID-19, we assessed lung involvement on the chest radiograph using the RALE score. We examined factors associated with the need for mechanical ventilation in bivariate and multivariate analysis. The area under the receiver operating curve (AUC) indicated the predictive value of the RALE score for need for mechanical ventilation. RESULTS: Among 189 patients, 90 (48%) were judged to need mechanical ventilation, although only 60 were placed on a ventilator. The factors associated with the need for mechanical ventilation were a RALE score >6 points, age >50 years, and presence of chronic kidney disease. The AUC for the RALE score was 60.9% (95% CI 52.9-68.9), indicating it was an acceptable predictor of needing mechanical ventilation. CONCLUSIONS: A score for extent of pulmonary oedema on the plain chest radiograph was a useful predictor of the need for mechanical ventilation of hospitalized patients with COVID-19.

Associations with perineal trauma during childbirth at home and in health facilities in indigenous municipalities in southern Mexico: a cross-sectional cluster survey.

BACKGROUND: Episiotomy and perineal tears remain common in vaginal deliveries. This study estimated the frequency of and factors associated with perineal tears, episiotomies, and postnatal infections among women in two predominantly indigenous municipalities in southern Mexico, where traditional midwives play an important role in women's health. METHODS: A cross-sectional study contacted women who gave birth in the previous three years. An administered questionnaire asked about place of delivery, birthing position, birth attendant, episiotomy, perineal tears, and wound infection after delivery. Cluster adjusted bivariate and then multivariate analysis examined factors potentially associated with self-reported perineal trauma (episiotomy and/or perineal tear). Key informant interviews sought insights into some of the findings. RESULTS: Among women with a vaginal delivery, 71% (876/1238) of indigenous women and 18% (36/197) of non-indigenous women delivered at home. Some 17% (247/1416) of women overall, and 33% (171/525) of those delivering in a health facility, reported an episiotomy during delivery. Among 171 women reporting an episiotomy in a health facility, 30% (52) also reported a perineal tear. Overall, 13% (190/1412) of women reported they had a perineal tear during delivery, 17% (86/515) of those delivering in a health facility and 12% (104/897) of those delivering at home. A quarter of the women had self-reported perineal trauma during their last delivery, 38% (196/511) of those delivering in a health facility and 18% (160/893) of those delivering at home. In bivariate analysis, indigenous ethnicity, home delivery, upright posture in labour, and delivery by a traditional midwife were associated with a lower risk of perineal trauma, while primiparas had a higher risk. In the final multivariate model, delivery by a traditional midwife was protective (ORa 0.41, 95%CIca 0.32-0.54) and primiparity was a risk factor (ORa 2.01, 95%CIca 1.5-2.68) for perineal trauma. Women suggested that fear of bad treatment and being cut made them unwilling to deliver in health facilities. CONCLUSIONS: The rate of perineal trauma among women giving birth in indigenous communities could be reduced by efforts to decrease the use of episiotomies in health facilities, and by opening a dialogue with traditional midwives to increase their interaction with formal health services.

Household costs for personal protection against mosquitoes: secondary outcomes from a randomised controlled trial of dengue prevention in Guerrero state, Mexico.

BACKGROUND: Dengue is a serious public health issue that affects households in endemic areas in terms of health and also economically, imposing costs for prevention and treatment of cases. The Camino Verde cluster-randomised controlled trial in Mexico and Nicaragua assessed the impact of evidence-based community engagement in dengue prevention. The Mexican arm of the trial was conducted in 90 randomly selected communities in three coastal regions of Guerrero State. This study reports an analysis of a secondary outcome of the trial: household use of and expenditure on anti-mosquito products. We examined whether the education and mobilisation activities of the trial motivated people to spend less on anti-mosquito products. METHODS: We carried out a household questionnaire survey in the trial communities in 2010 (12,312 households) and 2012 (5349 households in intervention clusters, 5142 households in control clusters), including questions about socio-economic status, self-reported dengue illness, and purchase of and expenditure on insecticide anti-mosquito products in the previous month. We examined expenditures on anti-mosquito products at baseline in relation to social vulnerability and we compared use of and expenditures on these products between intervention and control clusters in 2012. RESULTS: In 2010, 44.2% of 12,312 households reported using anti-mosquito products, with a mean expenditure of USD4.61 per month among those who used them. Socially vulnerable households spent less on the products. In 2012, after the intervention, the proportion of households who purchased anti-mosquito products in the last month was significantly lower in intervention clusters (47.8%; 2503/5293) than in control clusters (53.3%; 2707/5079) (difference - 0.05, 95% CIca -0.100 to -0.010). The mean expenditure on the products, among those households who bought them, was USD6.43; 30.4% in the intervention clusters and 36.7% in the control clusters spent more than this (difference - 0.06, 95% CIca -0.12 to -0.01). These expenditures on anti-mosquito products represent 3.3% and 3.8% respectively of monthly household income for the poorest 10% of the population in 2012. CONCLUSIONS: The Camino Verde community mobilisation intervention, as well as being effective in reducing dengue infections, was effective in reducing household use of and expenditure on insecticide anti-mosquito products. TRIAL REGISTRATION: ( ISRCTN27581154 ).

Coverage and beliefs about temephos application for control of dengue vectors and impact of a community-based prevention intervention: secondary analysis from the Camino Verde trial in Mexico.

BACKGROUND: Temephos in domestic water containers remains a mainstay of Latin American government programmes for control of Aedes aegypti and associated illnesses, including dengue. There is little published evidence about coverage of routine temephos programmes. A cluster randomised controlled trial of community mobilisation in Mexico and Nicaragua reduced vector indices, dengue infection, and clinical dengue cases. Secondary analysis from the Mexican arm of the trial examined temephos coverage and beliefs, and the impact of the trial on these outcomes. METHODS: The trial impact survey in December 2012, in 10,491 households in 45 intervention and 45 control clusters, asked about visits from the temephos programme, retention of applied temephos, and views about temephos and mosquito control. Fieldworkers noted if temephos was present in water containers. RESULTS: Some 42.4% of rural and 20.7% of urban households reported no temephos programme visits within the last 12 months. Overall, 42.0% reported they had temephos placed in their water containers less than 3 months previously. Fieldworkers observed temephos in at least one container in 21.1% of households. Recent temephos application and observed temephos were both significantly more common in urban households, when other household variables were taken into account; in rural areas, smaller households were more likely to have temephos present. Most households (74.4%) did not think bathing with water containing temephos carried any health risk. Half (51%) believed drinking or cooking with such water could be harmful and 17.6% were unsure. Significantly fewer households in intervention sites (16.5%) than in control sites (26.0%) (Risk Difference - 0.095, 95% confidence interval - 0.182 to -0.009) had temephos observed in their water; more households in intervention clusters (41.8%) than in control clusters (31.6%) removed the applied temephos quickly. Although fewer households in intervention sites (82.7%) compared with control sites (86.7%) (RD -0.04, 95% CI -0.067 to -0.013) agreed temephos and fumigation was the best way to avoid mosquitoes, the proportion believing this remained very high. CONCLUSION: Coverage with the government temephos programme was low, especially in rural areas. Despite an intervention encouraging non-chemical mosquito control, most households continued to believe that chemicals are the best control method. TRIAL REGISTRATION: ISRCTN: 27581154 .