Developing global climate anomalies suggest potential disease risks for 2006 – 2007

Abstract

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.

Prediction of a Rift Valley fever outbreak

“…By using information gained from previous RVF outbreaks (2, 12, 25, Fig. S2) and the analysis of satellite data, we mapped areas at elevated risk of RVF activity and issued monthly early-warning advisories over the Horn of Africa region starting in September 2006 (15,16).…”

“…Earth observation by satellite remote sensing over the last Ϸ30 years has enabled systematic mapping of driver indicators of climate variability including SST patterns, cloud cover, rainfall, and ecological indicators (primarily vegetation) on a global scale at high-temporal and moderate spatial resolutions (2,(15)(16)(17)(18). These systematic observations of the oceans, atmosphere, and land have made it possible to evaluate different aspects of climate variability and their relationships to disease outbreaks (16), in addition to providing valuable long-term climate and environmental data (Table S1). …”

“…Retrospective analysis of a satellite-derived time series vegetation measurements of photosynthetic activity, known as the normalized difference vegetation index (NDVI) (23), has shown that such data, in combination with other climate variables, can be used to map areas where RVF occurred (1,2,12,16,20). In 1999, the Department of Defense Global Emerging Infections, Surveillance and Response System, in collaboration with National Aeronautics and Space Administration (NASA) Goddard Space Flight Center and the United States Department of Agriculture, initiated a program to systematically monitor and map areas at potential risk for RVF outbreaks.…”

The Effect of Vaccination Coverage and Climate on Japanese Encephalitis in Sarawak, Malaysia

“…In addition, the influence El Niño/La Niña-Southern Oscillation (ENSO), a major modifier of climate in the tropics [10], on JEV transmission has received relatively little attention [5] despite its impact on other members of the Flavivirdae family, such as dengue [11]–[15]. Given that Malaysia, Indonesia and most of the Philippines usually are the first to experience ENSO-related impacts [16], investigation in these areas is warranted.…”

Effects of varying temporal scale on spatial models of mortality patterns attributed to pediatric diarrhea

“…Spatial and spatio-temporal patterns, spatial dependence, clusters and hotspots of diarrheal disease have been investigated and observed (Jepsen et al, 2009; Chaikaew et al, 2009; Leyk et al, in press). Purely temporal variations in spatial disease patterns and their association with risk factors have also been described (Kelly-Hope et al, 2008; Anyamba et al, 2006; Alonso et al, 2006). However, when disease outcome (registry) data are compiled in the context of health policy, they are typically aggregated over time in order to derive measures at the same time interval as reported causal risk factors (Abellan et al, 2008).…”