Biomedical subjects
Publications and source records attributed to P R Epstein.
The ranges of infectious diseases and vectors are changing in altitude, along with shifts in plant communities and the retreat of alpine glaciers. Additionally, extreme weather events create conditions conducive to clusters of insect-, rodent- and water-borne diseases. Accelerating climate change carries profound threats for public health and society.
West Nile virus is transmitted by urban-dwelling mosquitoes to birds and other animals, with occasional "spillover" to humans. While the means by which West Nile virus was introduced into the Americas in 1999 remain unknown, the climatic conditions that amplify diseases that cycle among urban mosquitoes, birds, and humans are warm winters and spring droughts. This information can be useful in generating early warning systems and mobilizing timely and the most environmentally friendly public health interventions. The extreme weather conditions accompanying long-term climate change may also be contributing to the spread of West Nile virus in the United States and Europe.
There is increasing evidence that environmental degradation may be contributing to an increase in marine-related diseases across a wide range of taxonomic groups. This includes a growing number of reports of both recreational and occupational users of marine waters developing gastrointestinal, respiratory, dermatologic, and ear, nose, and throat infections. The duration and type of exposure, concentration of pathogens, and host immunity determine the risk of infection. Public health authorities may not be able to accurately predict the risk of waterborne disease from marine waters due to the limitations of conventional monitoring, as well as erroneous perceptions of pathogen life span in marine systems. Pathogens undetectable by conventional methods may remain viable in marine waters, and both plankton and marine sediments may serve as reservoirs for pathogenic organisms, which can emerge to become infective when conditions are favorable. In this paper we address the environmental factors that may contribute to illness, the types of associated economic costs, the issues of water quality monitoring and the policy implications raised by the apparent rise in incidence of marine water-related illnesses.
Exposure to waterborne and foodborne pathogens can occur via drinking water (associated with fecal contamination), seafood (due to natural microbial hazards, toxins, or wastewater disposal) or fresh produce (irrigated or processed with contaminated water). Weather influences the transport and dissemination of these microbial agents via rainfall and runoff and the survival and/or growth through such factors as temperature. Federal and state laws and regulatory programs protect much of the U.S. population from waterborne disease; however, if climate variability increases, current and future deficiencies in areas such as watershed protection, infrastructure, and storm drainage systems will probably increase the risk of contamination events. Knowledge about transport processes and the fate of microbial pollutants associated with rainfall and snowmelt is key to predicting risks from a change in weather variability. Although recent studies identified links between climate variability and occurrence of microbial agents in water, the relationships need further quantification in the context of other stresses. In the marine environment as well, there are few studies that adequately address the potential health effects of climate variability in combination with other stresses such as overfishing, introduced species, and rise in sea level. Advances in monitoring are necessary to enhance early-warning and prevention capabilities. Application of existing technologies, such as molecular fingerprinting to track contaminant sources or satellite remote sensing to detect coastal algal blooms, could be expanded. This assessment recommends incorporating a range of future scenarios of improvement plans for current deficiencies in the public health infrastructure to achieve more realistic risk assessments.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
We examined the potential impacts of climate variability and change on human health as part of a congressionally mandated study of climate change in the United States. Our author team, comprising experts from academia, government, and the private sector, was selected by the federal interagency U.S. Global Change Research Program, and this report stems from our first 18 months of work. For this assessment we used a set of assumptions and/or projections of future climates developed for all participants in the National Assessment of the Potential Consequences of Climate Variability and Change. We identified five categories of health outcomes that are most likely to be affected by climate change because they are associated with weather and/or climate variables: temperature-related morbidity and mortality; health effects of extreme weather events (storms, tornadoes, hurricanes, and precipitation extremes); air-pollution-related health effects; water- and foodborne diseases; and vector- and rodent-borne diseases. We concluded that the levels of uncertainty preclude any definitive statement on the direction of potential future change for each of these health outcomes, although we developed some hypotheses. Although we mainly addressed adverse health outcomes, we identified some positive health outcomes, notably reduced cold-weather mortality, which has not been extensively examined. We found that at present most of the U.S. population is protected against adverse health outcomes associated with weather and/or climate, although certain demographic and geographic populations are at increased risk. We concluded that vigilance in the maintenance and improvement of public health systems and their responsiveness to changing climate conditions and to identified vulnerable subpopulations should help to protect the U.S. population from any adverse health outcomes of projected climate change.
Mass mortalities due to disease outbreaks have recently affected major taxa in the oceans. For closely monitored groups like corals and marine mammals, reports of the frequency of epidemics and the number of new diseases have increased recently. A dramatic global increase in the severity of coral bleaching in 1997-98 is coincident with high El Niño temperatures. Such climate-mediated, physiological stresses may compromise host resistance and increase frequency of opportunistic diseases. Where documented, new diseases typically have emerged through host or range shifts of known pathogens. Both climate and human activities may have also accelerated global transport of species, bringing together pathogens and previously unexposed host populations.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Climatic factors influence the emergence and reemergence of infectious diseases, in addition to multiple human, biological, and ecological determinants. Climatologists have identified upward trends in global temperatures and now estimate an unprecedented rise of 2.0 degrees C by the year 2100. Of major concern is that these changes can affect the introduction and dissemination of many serious infectious diseases. The incidence of mosquito-borne diseases, including malaria, dengue, and viral encephalitides, are among those diseases most sensitive to climate. Climate change would directly affect disease transmission by shifting the vector's geographic range and increasing reproductive and biting rates and by shortening the pathogen incubation period. Climate-related increases in sea surface temperature and sea level can lead to higher incidence of water-borne infectious and toxin-related illnesses, such as cholera and shellfish poisoning. Human migration and damage to health infrastructures from the projected increase in climate variability could indirectly contribute to disease transmission. Human susceptibility to infections might be further compounded by malnutrition due to climate stress on agriculture and potential alterations in the human immune system caused by increased flux of ultraviolet radiation. Analyzing the role of climate in the emergence of human infectious diseases will require interdisciplinary cooperation among physicians, climatologists, biologists, and social scientists. Increased disease surveillance, integrated modeling, and use of geographically based data systems will afford more anticipatory measures by the medical community. Understanding the linkages between climatological and ecological change as determinants of disease emergence and redistribution will ultimately help optimize preventive strategies.
Land mines in Mozambique are still causing death and injuries years after the initial dispute. Since 1980, 3400 people have had an amputation because of land mine injuries. However, there are no direct estimates of the number of deaths or casualties which are not treated in hospitals. In March, 1994, a medical team assembled by Physicians for Human Rights (PHR) conducted household surveys in the province of Manica and in the sub-district of Metuchira, province of Sofala. The object was to assess the frequency and severity of injuries and mortality caused by land mines in the civilian population. We found ratios of 8.1 and 16.7 casualties per 1000 living people in Manica and Metuchira, respectively. The prevalence of amputees was 3.2 per 1000 in Manica, and 2.3 in Metuchira. These figures are several folds higher than suggested by hospital data. The case fatality rate was 48%. Most of the victims were civilians (68%) and were injured by antipersonnel mines (81%). 16% of victims were women, and 7% were under 15 years of age. Our results suggest that the impact of land mines is substantially higher than originally thought.
Explore the source record for details and available documents.
Ecologists have begun to describe an environmental distress syndrome, whereby widespread loss of top predators and harsh environmental conditions are encouraging the selection of opportunistic pests and pathogens across a wide taxonomic range of plants and animals. Environmental change and pollutants stress individuals and populations, and this may be reflected in the global resurgence of infectious disease as these stresses cascade through the community assemblages of species. In 1993, the sudden appearance of a virulent, rodent-borne hantavirus in the arid US Southwest accompanied anomalous weather patterns, and a novel Vibrio cholerae variant (O139 Bengal) emerged in Asia where marine ecosystems are experiencing a pandemic of coastal algal blooms, apparently harboring and amplifying the agent. This paper suggests a framework for integrating the surveillance of health outcomes and key reservoir and vector species, with ecological and climatic monitoring.