to five times the normal risk (Tsai et al., 2004; Ogawa et al., 2000); putatively, this is due to the extreme stress and fear caused by severe earthquakes. Increased myocardial infarction cases were recorded following the Northridge earthquake in 1994 and the Hanshin (Kobe) earthquake of 1995. The Northridge earthquake also triggered an excess number of out-of-hospital cardiac arrests. Most of these cardiac arrests were due to underlying atherosclerosis, suggesting that the earthquake was a triggering event for deaths that would probably have occurred in the near future (Leor et al., 1996).

Psychosocial Stress Impacts

Disasters have also been linked to psychiatric disorders, most notably to post-traumatic stress disorder (PTSD). This is not surprising, as the etiology of PTSD is usually some sudden, extremely stressful, emotionally disruptive and wrenching event, frequently involving the death of others and the threat of death to oneself. There was evidence of PTSD in 68% of 160 disasters that were sampled in one review of natural disasters occurring between 1981 and 2001 (Norris et al., 2002). The severity was greater in developing countries than in developed countries. In the Mexican floods of 1999 the prevalence of PTSD was a striking 46% in Tezuitlan, and there was significant comorbidity with depressive disorder directly attributable to the personal and property losses associated with the floods (Norris et al., 2004). Similar comorbidity was noted in Turkey following the 2003 Bingol earthquake (Ozen and Sir, 2004). In addition, those affected by the 1999 Chi-Chi earthquake in Taiwan, perhaps compounded by the overall economic stress in Asia, were 1.46 times more likely to commit suicide after the earthquake (Chou et al., 2003). Mental health needs following disasters are significant and are not as well addressed as are the “physical” health needs (although admittedly the biological bases of psychiatric disorders militate against a dichotomy between “mental” and “physical”).


Human-induced land surface changes are the primary drivers of a range of infectious disease outbreaks and also modifiers of the transmission of endemic infections (Patz et al., 2000). Such anthropogenic landsurface changes include (1) deforestation and road construction; (2) agricultural encroachment and water projects (e.g., dam building, irrigation, and wetlands modification); (3) urban sprawl; and (4) extractive industries such as mining, quarrying, and oil drilling. These land surface changes cause a cascade of factors that heighten health threats, including

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