Dust and Human Health - Mineral Dust: A Key Player in the Earth System - page 392

In the 1960s a correlation between meningitis outbreaks and dry, dusty weather
was observed (Lapeyssonnie 1963 ). Recent studies have proposed a link between
environmental conditions such as low humidity and dusty conditions and meningitis
(Molesworth et al. 2003 ; Thomson et al. 2006 ). It has been suggested that the hot
dry weather may damage the mucosa in the nose and throat, thus providing a portal
of entry for the bacteria (Dukic et al. 2012 ; Agier et al. 2013 ). Several studies
have modeled population and environmental variables in an attempt to understand
and predict favorable conditions and locations for meningitis epidemics; these
have identified dust as an important factor (Agier et al. 2013 ;Molesworthetal.
2003 ; Thomson et al. 2006 ). Dukic et al. ( 2012 ) modeled environmental variables
in a study of meningitis outbreaks in Ghana and identified the current month
maximum temperature, total number of days with dust, previous month average
humidity at 3 pm, and burning biomass as the most significant predictors in their
full model. As there is some indication that the decrease in rainfall and severe
drought conditions may continue into the twenty-first century (Dukic et al. 2012 ),
the ability to make such predictions would allow public health officials to focus
resources such as personnel and supplies. Because an effective and inexpensive
vaccine has been developed (Roberts 2010 ), such advanced notice of a potential
epidemic could allow public health officials to target specific areas for vaccination,
possibly saving hundreds of lives. However, there are inherent difficulties associated
with modeling complex problems with numerous variables such as meningitis
outbreaks. Two studies have cited challenges associated with the limited accuracy
of data (i.e., population data), variables that may not reflect ground conditions (i.e.,
remote sensing or satellite data), a lack of exposure information, and understanding
how environmental variables may interact with each other (Molesworth et al. 2003 ;
Thomson et al. 2006 ).
Meningitis is not just endemic in Africa but disease estimates are not always
available for many countries in Asia (Vyse et al. 2011 ) or some regions of the
Middle East and North Africa (Ceyhan et al. 2012 ). Vyse et al. ( 2011 ) suggest that
meningococcal cases in Asia may be underreported, as epidemiological information
is lacking for several countries. This lack of information is in part due to healthcare
barriers to reporting disease, poor bacterial detection methods, and an absence of
surveillance methods (Vyse et al. 2011 ). In a review of epidemiological data for
countries in northern Africa and the Middle East, Ceyhan et al. ( 2012 ) found a
similar lack of surveillance and data collection. The implementation of standard
methods for data collection and surveillance is needed in addition to research to
understand the transmission and extent of this disease.

15.5.3 Hospitalization and Mortality Related

to Intercontinental Dust

There is increasing concern that desertification and the frequency and volume of
dusts produced will increase with climate change (Kuehn 2006 ). Recently, studies