Conclusion

Flooding is the most common type of natural disaster worldwide (4).  The public health impacts of flooding can be wide spread ranging from displacement of persons and compromise of personal hygiene to interruption of health care services or serious outbreaks related to contamination of waters sources (5).  Increased health risk exists not only during the periods of high water but also during the clean-up process that follows such natural disasters (6).

To assess the public health impacts of flooding caused by Tropical Storm Allison, the HDHHS Bureau of Epidemiology initiated infectious disease surveillance in local hospitals, emergency medical facilities, and emergency shelters.  These activities continued for a two-week period following the storm.  During this time, no unusual increases in those infectious diseases commonly associated with flooding disasters were identified in the greater Houston area.  Surveillance detected increases in hospital emergency room visits at selected facilities.  These facilities also reported staffing shortages.  However, the increases (and accompanying staffing problems) were explained by the temporary overflow of patients from incapacitated medical facilities.   

The findings of the various surveillance efforts are consistent with existing literature on flooding disasters in the United States.  Typical findings include the disruption of local services, including electricity and phone, a transient increase in hospital visits and displacement of individuals from their homes.  As in Houston, marked increases in the number of infectious diseases or outbreaks of specific disease were not identified during these investigations (5,7).

Data gathered and experienced gained during these surveillances activities will be used to develop a disaster preparedness protocol that will aid the governments of the City of Houston and Harris County in responding to future natural disasters in this area.

References
1. National Weather Service, unpublished data, http://www.nws.noaa.gov; http://www.nws.noaa.gov/oh/hic/archive/2001/010611.htm
2. American Red Cross, http://www.redcross.org/; http://www.redcross.org/news/ds/floods/010612houston.html
3. Houston Department of Health and Human Services--Rapid Needs Assessment June 16, 2001
4. French JG, Holt KW. Floods. In: Greeg MB, ed. The public health consequences of disasters. Atlanta: US Department of Health and Human Services, Public Health Service, CDC, 1989:69-78.
5. CDC. Public health consequences of a flood disaster - Iowa, 1993. MMWR 1993;42:653-6.
6. Lee LE, Fonseca V, Brett KM, et al. Active morbidity surveillance after Hurricane Andrew - Florida, 1992. JAMA 1993;270:591-4.
7. CDC. Morbidity Surveillance Following the Midwest Flood - Missouri, 1993. MMWR 1993;42:797-798