OBJECTIVETo determine the risk factors involved in the typhoon episodes and to put forward and evaluate the intervention measures.

METHODSWe defined a confirmed injury case as: 'a person with fall,scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am,August 12 to 6 pm, August 14 2004' and a death case as: 'a person with fall, scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am, August 12 to 12 am, August 18 2004'. We investigated all hospitalized injured cases in ten hospitals and telephoned to those who were not hospitalized and the cases of death. We did case-control study with 1 pair versus 2 cases. 74 cases were selected in ten hospitals. The controls were neighbors of the controls matched by occupation, sex, village, and within 5 years of age without injury in this typhoon. We asked the cases and the controls on their alertness regarding typhoon and what actions taken when typhoon arrived.

RESULTSThere were 392 injury cases in all ten hospitals and 50 death cases. The attack rate of injury was 27.3 per 100 000. The fatal rate was 11.3% with the death rate 3.1 per 100 000. We investigated 209 injury cases and 31 death cases. The number of cases who were injured from 1 to 6 hours before typhoon landing accounted for 64.6% (155) of all cases. The peak of epidemic curve was 4 hours before the landing of typhoon. Data on the analysis of 74 cases and 148 controls revealed that 42% (31) of the cases were outside their homes before and during typhoon compared to 15% (22) of the controls (OR = 3.9, 95% CI: 1.9-7.7). Compared with 20% (30) control persons (OR = 17,95% CI: 4.2-68). 28% (21) cases did not receive the alert of typhoon before it arrived compared with 18% (27) control persons (OR = 3.3, 95% CI:1.3-8.6). 53% (39) of the cases did not pay attention to the alert of typhoon before typhoon arrived.

CONCLUSIONStaying outdoor, not receiving or did not take seriously about the alert of typhoon seemed to be the risk factors of injury by the typhoon episode, suggesting that the government should increase the emergency preparedness and to raise the awareness on risks associated with typhoon.