ABSTRACT
Over the past several years, interest in the adverse effects induced by exposure to diesel exhaust (DE) has grown, at least partially owing to the findings suggesting a link between exposure to DE and enhanced susceptibility to developing asthma as well as exacerbation of existing asthma (Diaz-Sanchez et al., 2003; Nel et al., 2001; Pandya et al., 2002). Many studies have demonstrated that exposure to DE adversely affects the immune system by shifting the immune responses to those of a more allergic phenotype (Diaz-Sanchez, 1997; Wang et al., 1999). Although these findings are extremely important, little work has been done to examine the effects of DE on respiratory virus infections, which can also exacerbate asthma symptoms. This chapter will review the epidemiological findings linking particulate matter (PM) and respiratory virus infections and discuss potential interactions between DE and viral infections that have been shown in controlled experiments. Because, thus far, there have been only a few studies showing a direct link between exposure to DE and respiratory virus infections, some of the potential interactions are hypothetical, based on preliminary evidence or extrapolated from studies using other sources of particles, such as ambient PM or carbon black (CB) particles.
