Heatwaves and hospitalizations due to hyperthermia in defined climate regions in the conterminous USA.

Heatwaves are one of the deadliest natural disasters that occur annually with thousands of people seeking medical attention. The spatio-temporal synchronization between peaks in disease manifestation and high temperature provides important insights into the seasonal timing of the heatwave and the response it may cause with respect to emergence, severity, and duration. The objectives of this study are to examine the association between hospitalizations due to heat stroke in older adults and heat in the United States (US) and explore synchronization with respect to heatwave sequence, time of arrival, and regional climate. Three large data sets were utilized: daily hospitalization records of the US elderly between 1991 and 2006, annual demographic summaries on Medicare beneficiaries maintained by the Centers for Medicare and Medicaid Services (CMS), and nationwide daily meteorological observations. We modeled seasonal fluctuations in health outcomes, such as the timing and intensity of the seasonal peak in hospitalizations using refined harmonic GLM for eight climatically similar regions. During the 16-year study period, there were 40,019 heat-related hospitalizations (HRH) in the conterminous  US. The rates of HRH varied substantially across eight climatic regions: with the highest rate of 7.05 cases per million residents observed in areas with temperate arid summers and winters (TaTa) and the lowest rate of 0.67-in areas with cold moderately dry summers and arid winters (CdCa), where summer temperatures are about  18.3 °C and 12.1 °C, respectively. We detected 400 heatwaves defined as any day when the night time temperature is above its 90th percentile for the current and previous nights. The first seasonal heatwave in a season resulted in 4274 hospitalizations over 342 heatwave-days: 34.3% of 12,442 hospitalizations occurred in 26% of 1308 heatwave-days. The relative risks of increased HRH associated with the first and second heatwaves were 10.4 (95%CI: 8.5; 12.3) and 11.4 (95%CI: 9.6; 13.3), respectively, indicating the disproportional effects of early heatwave arrivals. The seasonal spike in heat stroke hospitalizations in regions with relatively similar annual temperatures, e.g. in areas with temperate moderately dry summers and winters (TdTa: 12.8 °C) and (TaTa: 11.1 °C) ranged between 4.5 (95%CI: 3.3; 5.5) and 11.0 (95%CI: 8.2; 14.9) cases per million residents, respectively, indicating substantial regional differences. The differences in heat-related hospitalizations and response to heatwaves are substantial among older adults residing in different climate regions of the conterminous US. The disproportionally high response to the early seasonal heatwave deserves special attention, especially in the context of prevention and decision support frameworks.

The use of remotely sensed environmental parameters for spatial and temporal schistosomiasis prediction across climate zones in Ghana.

Schistosomiasis control in sub-Saharan Africa is enacted primarily through preventive chemotherapy. Predictive models can play an important role in filling knowledge gaps in the distribution of the disease and help guide the allocation of limited resources. Previous modeling approaches have used localized cross-sectional survey data and environmental data typically collected at a discrete point in time. In this analysis, 8 years (2008-2015) of monthly schistosomiasis cases reported into Ghana's national surveillance system were used to assess temporal and spatial relationships between disease rates and three remotely sensed environmental variables: land surface temperature (LST), normalized difference vegetation index (NDVI), and accumulated precipitation (AP). Furthermore, the analysis was stratified by three major and nine minor climate zones, defined using a new climate classification method. Results showed a downward trend in reported disease rates (~ 1% per month) for all climate zones. Seasonality was present in the north with two peaks (March and September), and in the middle of the country with a single peak (July). Lowest disease rates were observed in December/January across climate zones. Seasonal patterns in the environmental variables and their associations with reported schistosomiasis infection rates varied across climate zones. Precipitation consistently demonstrated a positive association with disease outcome, with a 1-cm increase in rainfall contributing a 0.3-1.6% increase in monthly reported schistosomiasis infection rates. Generally, surveillance of neglected tropical diseases (NTDs) in low-income countries continues to suffer from data quality issues. However, with systematic improvements, our approach demonstrates a way for health departments to use routine surveillance data in combination with publicly available remote sensing data to analyze disease patterns with wide geographic coverage and varying levels of spatial and temporal aggregation.

Heat-Related Hospitalizations in Older Adults: An Amplified Effect of the First Seasonal Heatwave.

Older adults are highly vulnerable to the detriment of extreme weather. The rapid non-linear increase in heat-related morbidity is difficult to quantify, hindering the attribution of direct effects of exposure on severe health outcomes. We examine the effects of ambient temperatures on heat-related hospitalizations (HH) among the elderly in presence of strong seasonality and by assessing the effects caused by the first and subsequent seasonal heatwaves. We empirically derived the thresholds for a heatwave episode in Boston MSA based on 16 years of daily observations. We compared the health risks of heatwaves using the proposed and four alternative definitions. 701 cases of HH in older residents of Boston area were examined using harmonic regression models, designed to capture the non-linear effects of ambient temperatures and heatwave episodes when the night-time temperature is above 65.5 °F for 3 consecutive nights. The overall relative risk of HH associated with a heatwave episode was 6.9 [95%CI:4.8-9.8]. The relative risk of HH associated with the first heatwave increases up to 13.3 [95%CI:7.4-24.0]. The risk declined to 3.7 [95%CI:2.4-5.8] for the subsequent heatwave. Four other commonly used heatwave definitions confirmed these findings. Public health actions have to target the first heatwave to maximize the impact of preventive measures.

Piped water consumption in Ghana: A case study of temporal and spatial patterns of clean water demand relative to alternative water sources in rural small towns.

Continuous access to adequate quantities of safe water is essential for human health and socioeconomic development. Piped water systems (PWSs) are an increasingly common type of water supply in rural African small towns. We assessed temporal and spatial patterns in water consumption from public standpipes of four PWSs in Ghana in order to assess clean water demand relative to other available water sources. Low water consumption was evident in all study towns, which manifested temporally and spatially. Temporal variability in water consumption that is negatively correlated with rainfall is an indicator of rainwater preference when it is available. Furthermore, our findings show that standpipes in close proximity to alternative water sources such as streams and hand-dug wells suffer further reductions in water consumption. Qualitative data suggest that consumer demand in the study towns appears to be driven more by water quantity, accessibility, and perceived aesthetic water quality, as compared to microbiological water quality or price. In settings with chronic under-utilization of improved water sources, increasing water demand through household connections, improving water quality with respect to taste and appropriateness for laundry, and educating residents about health benefits of using piped water should be prioritized. Continued consumer demand and sufficient revenue generation are important attributes of a water service that ensure its function over time. Our findings suggest that analyzing water consumption of existing metered PWSs in combination with qualitative approaches may enable more efficient planning of community-based water supplies and support sustainable development.

Hospitalizations due to selected infections caused by opportunistic premise plumbing pathogens (OPPP) and reported drug resistance in the United States older adult population in 1991-2006.

The Flint Water Crisis-due to changes of water source and treatment procedures-has revealed many unsolved social, environmental, and public health problems for US drinking water, including opportunistic premise plumbing pathogens (OPPP). The true health impact of OPPP, especially in vulnerable populations such as the elderly, is largely unknown. We explored 108 claims in the largest US national uniformly collected data repository to determine rates and costs of OPPP-related hospitalizations. In 1991-2006, 617,291 cases of three selected OPPP infections resulted in the elderly alone of $0.6 billion USD per year of payments. Antibiotic resistance significantly increased OPPP illness costs that are likely to be underreported. More precise estimates for OPPP burdens could be obtained if better clinical, microbiological, administrative, and environmental monitoring data were cross-linked. An urgent dialog across governmental and disciplinary divides, and studies on preventing OPPP through drinking water exposure, are warranted.

Redefining climate regions in the United States of America using satellite remote sensing and machine learning for public health applications.

Existing climate classification has not been designed for an efficient handling of public health scenarios. This work aims to design an objective spatial climate regionalization method for assessing health risks in response to extreme weather. Specific climate regions for the conterminous United States of America (USA) were defined using satellite remote sensing (RS) data and compared with the conventional Köppen-Geiger (KG) divisions. Using the nationwide database of hospitalisations among the elderly (≥65 year olds), we examined the utility of a RS-based climate regionalization to assess public health risk due to extreme weather, by comparing the rate of hospitalisations in response to thermal extremes across climatic regions. Satellite image composites from 2002-2012 were aggregated, masked and compiled into a multi-dimensional dataset. The conterminous USA was classified into 8 distinct regions using a stepwise regionalization approach to limit noise and collinearity (LKN), which exhibited a high degree of consistency with the KG regions and a well-defined regional delineation by annual and seasonal temperature and precipitation values. The most populous was a temperate wet region (10.9 million), while the highest rate of hospitalisations due to exposure to heat and cold (9.6 and 17.7 cases per 100,000 persons at risk, respectively) was observed in the relatively warm and humid south-eastern region. RS-based regionalization demonstrates strong potential for assessing the adverse effects of severe weather on human health and for decision support. Its utility in forecasting and mitigating these effects has to be further explored.