Issue link: https://hi.iaq.net/i/191637
Climate Change, the Indoor Environment, and Health INFECTIOUS AGENTS AND PESTS 167 that can thrive in a particular climate. For example, if the northeast United States becomes warmer and more humid, such mites as Blomia tropicalis— which is found in Puerto Rico—might extend their range northward in the United States (Acosta, 2008; Montealegre et al., 1997). Epidemiology Current dust mite sensitization patterns in the United States Most of what is known about current dust mite sensitization patterns in the United States is from the National Health and Nutrition Examination Survey (NHANES) population-based sample of the general population and from childhood-asthma studies (Table 6-1). The NHANES data did not focus on dust mite sensitization more widely than the regional level. However, the National Cooperative Inner-City Asthma Study (NCICAS), Childhood Asthma Management Program (CAMP), and Inner-City Asthma Study (ICAS) show that, among children who have asthma, dust mite sensitization varied by city. How allergen avoidance could affect sensitization patterns Early-life environmental exposures are key in the development of allergic sensitization (Illi et al., 2006; Lau et al., 2000). It is controversial which factors are most important, such as early-life pet ownership and early-life endotoxin exposure (Holt and Thomas, 2005), but it is clear that those with a genetic predisposition to inhalant allergies tend to become sensitized to what is in their environment (Chew et al., 2008; Eldeirawi et al., 2005; Huss et al., 2001; Ingram et al., 1995; Montealegre et al., 2004; Phipatanakul et al., 2000a,b). The CAMP showed that of children who had asthma in Albuquerque, B altimore, Boston, Denver, St. Louis, San Diego, Seattle, and Toronto, those in Denver and Albuquerque had the lowest concentrations of dust mites in their homes and the lowest prevalence of dust mite sensitization (33.1% and 21.5%, respectively) (Huss et al., 2001). If climate change leads to longer heat waves, areas with climates similar to that of Albuquerque could expand, and residents in those areas would experience not only decreased allergen exposure (which would lead to fewer symptoms) but changes in the pattern of their allergic sensitization. How asthma incidence patterns could be affected Generally speaking—that is, without regard to the sensitizing agent(s)—asthma mortality and morbidity rates exhibit geographic, regional, and seasonal differences in the United States. Rates are elevated in urban areas when compared to rural areas (Carr et al., 1992; Grant et al., 1999; Weiss and Wagner, 1990), with New York City, Chicago, and Phoenix having consistently high mortality and hospitalization rates (Carr et al., 1992; Lang and Polansky, 1994; Copyright © National Academy of Sciences. All rights reserved.