Following on from the previous Chapter are three contributions that cover the remaining “classica... more Following on from the previous Chapter are three contributions that cover the remaining “classical” areas for applicatio ns (alongside agriculture) of hydrology and health. Water management is the focus in the first section, in which a number of projects are described whereby historical and forecast information is used directly in planning specific actions; in this cas e the forecaster-user chain is short and manageable at a personal level. Next is a detailed account of the steps required to establish climate services in the health area. Finally, Early Warning Systems are described. Early Warning Systems have not tended to use predictions until recently, traditionally having been built around historical observations. In that context Early Warning Systems provide an example of an application mainly designed for humanitarian benefit built solely using climate data alongside other information, but with growing use of predictions. A worked example is included establishing the impact of climate variability on disease incidence, the results of which provide a basis for incorporating seasonal climate forecasts into a Malaria Early Warning System in southern Africa.
Recent advances in knowledge about the climate system have increased the ability of meteorologist... more Recent advances in knowledge about the climate system have increased the ability of meteorologists to forecast extreme weather and climate events, such as floods and heatwaves. Public health agencies and authorities have had limited involvement in the development of early warning systems to take advantage of these forecasts to reduce the burden of disease associated with extreme events. Instead, public health has focused on surveillance and response activities to identify disease outbreaks following an extreme event. Although these systems are critical for detecting and investigating disease outbreaks, they are not designed for identifying and preventing many of the adverse health outcomes associated with extreme events. Designing and implementing effective disease prediction and preventions programs that incorporate advances in weather and climate forecasting have the potential to reduce illness, injury, and death. Critical components of an early warning system include the weather forecast, disease prediction models, and a response plan designed to pro-actively undertake activities to reduce projected adverse health outcomes. Because climate change may increase climate variability, early warning systems can both reduce current vulnerability to extreme events and increase the capacity to cope with a future that may be characterized by more frequent and more intense events.
The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent s... more The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian Tlymphotropic virus type 3 (STLV-3) subtype D viruses from two different monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated.
The recent discovery of human T-lymphotropic virus type 3 (HTLV-3) in Cameroon highlights the imp... more The recent discovery of human T-lymphotropic virus type 3 (HTLV-3) in Cameroon highlights the importance of expanded surveillance to better understand the prevalence and public health impact of this new retrovirus. HTLV diversity was investigated in 408 persons in rural Cameroon who reported simian exposures. Plasma from 29 persons (7.2%) had reactive serology. HTLV tax sequences were detected in 3 persons. Phylogenetic analysis confirmed HTLV-1 infection in two individuals and HTLV-3 infection in a third person (Cam2013AB). The complete proviral genome from Cam2013AB shared 98% identity and clustered tightly in distinct lineage with simian T-lymphotropic virus type 3 (STLV-3) subtype D recently identified in two guenon monkeys near this person's village. These results document a fourth HTLV-3 infection with a new and highly divergent strain we designate HTLV-3 (Cam2013AB) subtype D demonstrating the existence of a broad HTLV-3 diversity likely originating from multiple zoonotic transmissions of divergent STLV-3.
Philosophical Transactions of The Royal Society B: Biological Sciences, 2005
Food security assessment in sub-Saharan Africa requires simultaneous consideration of multiple so... more Food security assessment in sub-Saharan Africa requires simultaneous consideration of multiple socio-economic and environmental variables. Early identification of populations at risk enables timely and appropriate action. Since large and widely dispersed populations depend on rainfed agriculture and pastoralism, climate monitoring and forecasting are important inputs to food security analysis. Satellite rainfall estimates (RFE) fill in gaps in station observations, and serve as input to drought index maps and crop water balance models. Gridded rainfall time-series give historical context, and provide a basis for quantitative interpretation of seasonal precipitation forecasts. RFE are also used to characterize flood hazards, in both simple indices and stream flow models. In the future, many African countries are likely to see negative impacts on subsistence agriculture due to the effects of global warming. Increased climate variability is forecast, with more frequent extreme events. Ethiopia requires special attention. Already facing a food security emergency, troubling persistent dryness has been observed in some areas, associated with a positive trend in Indian Ocean sea surface temperatures. Increased African capacity for rainfall observation, forecasting, data management and modelling applications is urgently needed. Managing climate change and increased climate variability require these fundamental technical capacities if creative coping strategies are to be devised.
Background: This paper examines how the cost-effectiveness of IRS varies depending on the severit... more Background: This paper examines how the cost-effectiveness of IRS varies depending on the severity of transmission and level of programme coverage and how efficiency could be improved by incorporating climate information into decision making for malaria control programmes as part of an integrated Malaria Early Warning and Response System (MEWS).
Having reliable forecasts is critical now for producers, malaria-endemic countries and agencies i... more Having reliable forecasts is critical now for producers, malaria-endemic countries and agencies in order to adapt production and procurement of the artemisinin-based combination treatments (ACTs), the new first-line treatments of malaria. There is no ideal method to quantify drug requirements for malaria. Morbidity data give uncertain estimations. This study uses drug consumption to provide elements to help estimate quantities and financial requirements of ACTs.
Background: El Niño/Southern Oscillation (ENSO) related climate anomalies have been shown to have... more Background: El Niño/Southern Oscillation (ENSO) related climate anomalies have been shown to have an impact on infectious disease outbreaks. The Climate Prediction Center of the National Oceanic and Atmospheric Administration (NOAA/CPC) has recently issued an unscheduled El Niño advisory, indicating that warmer than normal sea surface temperatures across the equatorial eastern Pacific may have pronounced impacts on global tropical precipitation patterns extending into the northern hemisphere particularly over North America. Building evidence of the links between ENSO driven climate anomalies and infectious diseases, particularly those transmitted by insects, can allow us to provide improved long range forecasts of an epidemic or epizootic. We describe developing climate anomalies that suggest potential disease risks using satellite generated data.
Alfred J. Lotka, considered as one of the founders of mathematical demography, wrote seminal arti... more Alfred J. Lotka, considered as one of the founders of mathematical demography, wrote seminal articles and books from 1907 to his death in 1949. He elaborated in particular the concepts of stable age-distribution of a population and of natural rate of increase of a population. His scientific work is extensive and various: he wrote on malaria epidemiology, on population forecasts,
THE obituary notice of Sir Patrick Manson, in NATURE of May 6, concludes with the hope that his m... more THE obituary notice of Sir Patrick Manson, in NATURE of May 6, concludes with the hope that his memory may ever be kept alive as the Father of Tropical Medicine. As to this it is not difficult to forecast that the medical profession will fully concur. To the enthusiasm and inspiring teaching of Manson is due the existence of tropical medicine as a speciality, and the ever extending benefit tropical races receive at the hands of men trained on the lines indicated by him.
Malaria epidemics affect nonimmune populations in many highland and semi-arid areas of Africa. Ef... more Malaria epidemics affect nonimmune populations in many highland and semi-arid areas of Africa. Effective prevention of these epidemics is challenging, particularly in the highlands where predictive accuracy of indicators is not suffi ciently high to allow decisions involving expensive measures such as indoor residual spraying of insecticides. Advances in geographic information systems have proved useful in stratifi cation of areas
Background: An accurate forecast of global demand is essential to stabilize the market for artemi... more Background: An accurate forecast of global demand is essential to stabilize the market for artemisinin-based combination therapy (ACT) and to ensure access to high-quality, life-saving medications at the lowest sustainable prices by avoiding underproduction and excessive overproduction, each of which can have negative consequences for the availability of affordable drugs. A robust forecast requires an understanding of the resources available to support procurement of these relatively expensive antimalarials, in particular from the Global Fund, at present the single largest source of ACT funding.
This paper discusses how data obtained from Earth-sensing satellite systems can be used in the ef... more This paper discusses how data obtained from Earth-sensing satellite systems can be used in the efforts to prevent and treat malaria in developing countries especially in Africa. The paper describes how representatives from WHO and various space and oceanographic agencies have agreed to meet under the auspices of the Global Earth Observation System of Systems (GEOSS) to advance human health
Citation: Chaves LF, Pascual M (2006) Climate cycles and forecasts of cutaneous leishmaniasis, a ... more Citation: Chaves LF, Pascual M (2006) Climate cycles and forecasts of cutaneous leishmaniasis, a nonstationary vector-borne disease. PLoS Med 3(8): e295.
Transmitted by the Anopheles mosquito, malaria is the world's most deadly vector born... more Transmitted by the Anopheles mosquito, malaria is the world's most deadly vector borne disease. Mortality, currently estimated at over 1 million people per year, is rising. Epidemics account for up to 25% of the disease burden, and these too are increasing. This global resurgence in both incidence of epidemics and their mortality has been attributed to several factors: drug-resistant parasites,
Following on from the previous Chapter are three contributions that cover the remaining “classica... more Following on from the previous Chapter are three contributions that cover the remaining “classical” areas for applicatio ns (alongside agriculture) of hydrology and health. Water management is the focus in the first section, in which a number of projects are described whereby historical and forecast information is used directly in planning specific actions; in this cas e the forecaster-user chain is short and manageable at a personal level. Next is a detailed account of the steps required to establish climate services in the health area. Finally, Early Warning Systems are described. Early Warning Systems have not tended to use predictions until recently, traditionally having been built around historical observations. In that context Early Warning Systems provide an example of an application mainly designed for humanitarian benefit built solely using climate data alongside other information, but with growing use of predictions. A worked example is included establishing the impact of climate variability on disease incidence, the results of which provide a basis for incorporating seasonal climate forecasts into a Malaria Early Warning System in southern Africa.
Recent advances in knowledge about the climate system have increased the ability of meteorologist... more Recent advances in knowledge about the climate system have increased the ability of meteorologists to forecast extreme weather and climate events, such as floods and heatwaves. Public health agencies and authorities have had limited involvement in the development of early warning systems to take advantage of these forecasts to reduce the burden of disease associated with extreme events. Instead, public health has focused on surveillance and response activities to identify disease outbreaks following an extreme event. Although these systems are critical for detecting and investigating disease outbreaks, they are not designed for identifying and preventing many of the adverse health outcomes associated with extreme events. Designing and implementing effective disease prediction and preventions programs that incorporate advances in weather and climate forecasting have the potential to reduce illness, injury, and death. Critical components of an early warning system include the weather forecast, disease prediction models, and a response plan designed to pro-actively undertake activities to reduce projected adverse health outcomes. Because climate change may increase climate variability, early warning systems can both reduce current vulnerability to extreme events and increase the capacity to cope with a future that may be characterized by more frequent and more intense events.
The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent s... more The recent discoveries of novel human T-lymphotropic virus type 3 (HTLV-3) and highly divergent simian Tlymphotropic virus type 3 (STLV-3) subtype D viruses from two different monkey species in southern Cameroon suggest that the diversity and cross-species transmission of these retroviruses are much greater than currently appreciated.
The recent discovery of human T-lymphotropic virus type 3 (HTLV-3) in Cameroon highlights the imp... more The recent discovery of human T-lymphotropic virus type 3 (HTLV-3) in Cameroon highlights the importance of expanded surveillance to better understand the prevalence and public health impact of this new retrovirus. HTLV diversity was investigated in 408 persons in rural Cameroon who reported simian exposures. Plasma from 29 persons (7.2%) had reactive serology. HTLV tax sequences were detected in 3 persons. Phylogenetic analysis confirmed HTLV-1 infection in two individuals and HTLV-3 infection in a third person (Cam2013AB). The complete proviral genome from Cam2013AB shared 98% identity and clustered tightly in distinct lineage with simian T-lymphotropic virus type 3 (STLV-3) subtype D recently identified in two guenon monkeys near this person's village. These results document a fourth HTLV-3 infection with a new and highly divergent strain we designate HTLV-3 (Cam2013AB) subtype D demonstrating the existence of a broad HTLV-3 diversity likely originating from multiple zoonotic transmissions of divergent STLV-3.
Philosophical Transactions of The Royal Society B: Biological Sciences, 2005
Food security assessment in sub-Saharan Africa requires simultaneous consideration of multiple so... more Food security assessment in sub-Saharan Africa requires simultaneous consideration of multiple socio-economic and environmental variables. Early identification of populations at risk enables timely and appropriate action. Since large and widely dispersed populations depend on rainfed agriculture and pastoralism, climate monitoring and forecasting are important inputs to food security analysis. Satellite rainfall estimates (RFE) fill in gaps in station observations, and serve as input to drought index maps and crop water balance models. Gridded rainfall time-series give historical context, and provide a basis for quantitative interpretation of seasonal precipitation forecasts. RFE are also used to characterize flood hazards, in both simple indices and stream flow models. In the future, many African countries are likely to see negative impacts on subsistence agriculture due to the effects of global warming. Increased climate variability is forecast, with more frequent extreme events. Ethiopia requires special attention. Already facing a food security emergency, troubling persistent dryness has been observed in some areas, associated with a positive trend in Indian Ocean sea surface temperatures. Increased African capacity for rainfall observation, forecasting, data management and modelling applications is urgently needed. Managing climate change and increased climate variability require these fundamental technical capacities if creative coping strategies are to be devised.
Background: This paper examines how the cost-effectiveness of IRS varies depending on the severit... more Background: This paper examines how the cost-effectiveness of IRS varies depending on the severity of transmission and level of programme coverage and how efficiency could be improved by incorporating climate information into decision making for malaria control programmes as part of an integrated Malaria Early Warning and Response System (MEWS).
Having reliable forecasts is critical now for producers, malaria-endemic countries and agencies i... more Having reliable forecasts is critical now for producers, malaria-endemic countries and agencies in order to adapt production and procurement of the artemisinin-based combination treatments (ACTs), the new first-line treatments of malaria. There is no ideal method to quantify drug requirements for malaria. Morbidity data give uncertain estimations. This study uses drug consumption to provide elements to help estimate quantities and financial requirements of ACTs.
Background: El Niño/Southern Oscillation (ENSO) related climate anomalies have been shown to have... more Background: El Niño/Southern Oscillation (ENSO) related climate anomalies have been shown to have an impact on infectious disease outbreaks. The Climate Prediction Center of the National Oceanic and Atmospheric Administration (NOAA/CPC) has recently issued an unscheduled El Niño advisory, indicating that warmer than normal sea surface temperatures across the equatorial eastern Pacific may have pronounced impacts on global tropical precipitation patterns extending into the northern hemisphere particularly over North America. Building evidence of the links between ENSO driven climate anomalies and infectious diseases, particularly those transmitted by insects, can allow us to provide improved long range forecasts of an epidemic or epizootic. We describe developing climate anomalies that suggest potential disease risks using satellite generated data.
Alfred J. Lotka, considered as one of the founders of mathematical demography, wrote seminal arti... more Alfred J. Lotka, considered as one of the founders of mathematical demography, wrote seminal articles and books from 1907 to his death in 1949. He elaborated in particular the concepts of stable age-distribution of a population and of natural rate of increase of a population. His scientific work is extensive and various: he wrote on malaria epidemiology, on population forecasts,
THE obituary notice of Sir Patrick Manson, in NATURE of May 6, concludes with the hope that his m... more THE obituary notice of Sir Patrick Manson, in NATURE of May 6, concludes with the hope that his memory may ever be kept alive as the Father of Tropical Medicine. As to this it is not difficult to forecast that the medical profession will fully concur. To the enthusiasm and inspiring teaching of Manson is due the existence of tropical medicine as a speciality, and the ever extending benefit tropical races receive at the hands of men trained on the lines indicated by him.
Malaria epidemics affect nonimmune populations in many highland and semi-arid areas of Africa. Ef... more Malaria epidemics affect nonimmune populations in many highland and semi-arid areas of Africa. Effective prevention of these epidemics is challenging, particularly in the highlands where predictive accuracy of indicators is not suffi ciently high to allow decisions involving expensive measures such as indoor residual spraying of insecticides. Advances in geographic information systems have proved useful in stratifi cation of areas
Background: An accurate forecast of global demand is essential to stabilize the market for artemi... more Background: An accurate forecast of global demand is essential to stabilize the market for artemisinin-based combination therapy (ACT) and to ensure access to high-quality, life-saving medications at the lowest sustainable prices by avoiding underproduction and excessive overproduction, each of which can have negative consequences for the availability of affordable drugs. A robust forecast requires an understanding of the resources available to support procurement of these relatively expensive antimalarials, in particular from the Global Fund, at present the single largest source of ACT funding.
This paper discusses how data obtained from Earth-sensing satellite systems can be used in the ef... more This paper discusses how data obtained from Earth-sensing satellite systems can be used in the efforts to prevent and treat malaria in developing countries especially in Africa. The paper describes how representatives from WHO and various space and oceanographic agencies have agreed to meet under the auspices of the Global Earth Observation System of Systems (GEOSS) to advance human health
Citation: Chaves LF, Pascual M (2006) Climate cycles and forecasts of cutaneous leishmaniasis, a ... more Citation: Chaves LF, Pascual M (2006) Climate cycles and forecasts of cutaneous leishmaniasis, a nonstationary vector-borne disease. PLoS Med 3(8): e295.
Transmitted by the Anopheles mosquito, malaria is the world's most deadly vector born... more Transmitted by the Anopheles mosquito, malaria is the world's most deadly vector borne disease. Mortality, currently estimated at over 1 million people per year, is rising. Epidemics account for up to 25% of the disease burden, and these too are increasing. This global resurgence in both incidence of epidemics and their mortality has been attributed to several factors: drug-resistant parasites,
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