Potential of environmental models to predict meningitis epidemics in Africa

Abstract

Summaryobjectives Meningococcal meningitis is a major public health problem in Africa. This report explores the potential for climate/environmental models to predict the probability of occurrence of meningitis epidemics.methods Time series of meningitis cases by month and district were obtained for Burkina Faso, Niger, Mali and Togo (536 district-years). Environmental information (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999) for the continent [soil and land-cover type, aerosol index, vegetation greenness (NDVI), cold cloud duration (CCD) and rainfall] was used to develop models to predict the incidence of meningitis. Meningitis incidence, dust, rainfall, NDVI and CCD were analysed as anomalies (mean minus observed value). The models were developed using univariate and stepwise multi-variate linear regression.results Anomalies in annual meningitis incidence at district level were related to monthly climate anomalies. Significant relationships were found for both estimates of rainfall and dust in the pre-, post-and epidemic season. While present in all land-cover classes these relationships were strongest in savannah areas.conclusions Predicting epidemics of meningitis could be feasible. To fully develop this potential, we require (a) a better understanding of the epidemiological and environmental phenomena underpinning epidemics and how satellite derived climate proxies reflect conditions on the ground and (b) more extensive epidemiological and environmental datasets. Climate forecasting tools capable of predicting climate variables 3-6 months in advance of an epidemic would increase the lead-time available for control strategies. Our increased capacity for data processing; the recent improvements in meningitis surveillance in preparation for the distribution of the impending conjugate vaccines and the development of other early warning systems for epidemic diseases in Africa, favours the creation of these models.

Desert dust impacts on human health: an alarming worldwide reality and a need for studies in West Africa

“…on the implications of microorganisms in clouds of desert dust) were excluded. Despite the fact that the occurrence of meningitis has been associated with desert dust events (Sultan et al 2005; Thomson et al 2006), unexpectedly, no studies on meningitis were returned by the query. A total of 50 individual relevant articles met our inclusion/exclusion criteria (N050).…”

Seasonality of meningitis in Africa and climate forcing: aerosols stand out

“…Reporting error or delays are relatively unlikely, and should, however, affect data in a spatially and temporally consistent way. Second, climate estimates are obtained from reanalysis, which are the most representative estimates we can currently obtain, and are widely used by the climate research community [19,[61][62][63]. Third, the AI representativeness has been tested: although it is perfectible, especially in terms of capturing the intensity of dust events in the dry season, it was proved to perform well in capturing the timing of those events [64 -66].…”

Seasonal cycle of desert aerosols in western Africa: analysis of the coastal transition with passive and active sensors

“…Their impact on the marine ecosystem and particularly on oceanic primary production (Duce and Tindale, 1991;Baker et al, 2003;Mills et al, 2004;Jickells et al, 2005;Mahowald et al, 2009) still remains uncertain and difficult to assess because of the composition of these particles and of physicochemical processes affecting them (e.g., Friese et al, 2016). Mineral dust deposition also has a negative impact on human health and are responsible for meningitis epidemics and cardiac diseases (Thomson et al, 2006;Martiny and Chiapello, 2013;Diokhane et al, 2016;Prospero et al, 2005;Griffin, 2007).…”