Rapid community health and needs assessments after Hurricanes Isabel and Charley—North Carolina, 2003-2004

Morbidity and Mortality Weekly Report, Sept 17, 2004 by J. Morrow, E. Norman, R. Dickens, H. Garrison, T. Morris, K. Henderson, H. Swygard, S. Ramsey, M. Salyers, B. Worsham, J. Kirkpatrick, J. Engel, G. Ghneim, M. Davies, K Sanford, W. Service, Daley. W.R., S. Young

On September 18, 2003, Hurricane Isabel, a Category 2 hurricane, made landfall on the Outer Banks of North Carolina (NC). The storm, moving to the northeast with winds exceeding 100 mph, caused extensive power outages and structural damage in northeastern NC and southern Virginia. In NC, approximately 762,000 residents lost power during the storm, and the shelter population peaked at an estimated 16,600 persons. Six storm-related fatalities were reported, and 26 eastern NC counties were included in a federal disaster area declaration (1). The North Carolina Division of Public Health (NCDPH) activated the Office of Public Health Preparedness and Response (PHPR) and seven Public Health Regional Surveillance Teams (PHRSTs) to conduct a rapid community health and needs assessment for the affected population. CDC deployed staff to provide technical support to NCDPH. The assessment determined that the majority of public health emergencies resulted from electric power outages, which affected access to food, water, and medical care. Data and recommendations were provided immediately to local and state emergency responders, who used the information to direct Hurricane Isabel recovery efforts and also to improve the assessment, which was next deployed in August 2004 with Hurricane Charley.

Two days after Hurricane Isabel struck, PHPR obtained information about storm damage from field assessments conducted by PHRSTs, reports from local health directors, damage reports from local emergency management offices, and aerial surveillance by the North Carolina Division of Emergency Management. This information was used to select a sample of 14 counties * in the most severely affected area of the state. Tire Outer Banks barrier islands were excluded from the sample because the majority of residents left the islands before storm landfall, and travel to the islands was restricted after the hurricane.

NCDPH and CDC developed a modified cluster-sampling method for population-based sampling in post-disaster needs assessments (2,3). Census blocks within the affected area were assembled into clusters of five blocks. In sparsely populated areas, blocks were combined to compensate for the low number of households in individual census blocks. Thirty census clusters were then selected with the probability of selection proportionate to the number of occupied housing units in the cluster. Occupied housing unit estimates were based on data from the 2000 U.S. Census. Assessment teams were composed of PHRST staff, with the assistance of students from the University of North Carolina School of Public Health and volunteers from other state agencies. Spanish-speaking interviewers were placed on teams assigned to census groups with large Hispanic populations. Language barriers did not prevent communication or completion of any interviews.

From a central area of the assigned cluster, teams moved sequentially along roadways to collect interviews at seven households in each cluster. In multiple-family dwellings (e.g., apartment buildings), one household was chosen randomly from each building. On Sunday, September 21, the teams collected 210 interviews. NCDPH and CDC staff entered data and conducted weighted cluster analysis by using EpiInfo. Data were analyzed to report the estimated proportion and projected number of households with a specific need or condition with a 95% confidence interval. On September 22, the report was submitted electronically to the Public Health Command Center in Raleigh, 4 days after the hurricane had struck. The survey population was representative of the 93,738 occupied housing units identified by the 2000 U.S. Census; response rate was 62.3%, with 210 interviews completed. Households in the 14-county sample had an average of 2.7 persons before and after the hurricane. Children aged <2 years represented 4% of the sampled population, and adults aged [greater then or equal to]65 years represented 19%. Of the 210 households, 162 (77%) were in permanently anchored single-family structures, 44 (21%) were in mobile homes, and four (2%) were in multiple-family dwellings (e.g., apartment buildings).

A total of 137 (65%) households sampled were without electricity on the date of the survey (Table). Portable electrical generators were used after the hurricane in 64 (30%) homes. Other basic service interruptions included 50 (24%) households without running water, 44 (21%) without working cellular or landline telephone service, and 48 (23%) without a battery-operated radio. A total of 90 (43%) households were using bottled water, and 26 (12%) did not have a 3-day supply of food; 68 (32%) households had more than minimal damage but were habitable, and five (2%) were reported uninhabitable.

Few hurricane-related injuries or illnesses were reported. Two (1%) households had a member who experienced injury as a result of the hurricane, and 10 (5%) had a member who experienced hurricane-related illness. A total of 17 (8%) households reported a member who required medical care. NCDPH and CDC provided assessment results to local health departments, local emergency operations centers, and the NC emergency operations center. Data from the report were used to direct resources, including feeding stations and allocation of bottled water, to affected communities. Information about the risks of using portable electrical generators was provided to local health departments.