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Section 1: Public Health Preparedness in the States and DC

Disease Detection and Investigation

Improving the Public Health Workforce and Disease Surveillance

The sooner public health professionals can detect the source and spread of diseases or other health threats and investigate their effects in the community, the more quickly they can protect the public. Progress in disease detection and investigation supports CDC preparedness goals in the areas of prevention, detection and reporting, investigation, and recovery. Using cooperative agreement funds, public health departments have improved their abilities to detect and investigate diseases by enhancing the public health workforce and disease surveillance systems.

Increased Workforce Capacity

In 2006, the cooperative agreement funded 531 epidemiologists. The majority of these epidemiologists specialized either in emergency response (291) or infectious diseases (199).5

A skilled public health workforce. Epidemiologists, or “disease detectives,” detect and investigate health threats and disease patterns. They might identify contaminated food causing illness, assess the number of people injured and types of injuries resulting from a disaster, or determine causes of a sudden onset of fever in a community. They also work to minimize the negative effects of a health threat in a community.


According to a 2006 CSTE survey, the total number of epidemiologists in state public health departments working in emergency response has doubled since 2001 (Table 3).

A connected public health workforce. The increase in the users of the Epidemic Information Exchange (Epi-X), a secure CDCbased communications system that helps track disease outbreaks, suggests that public health professionals are more connected (Table 3). Epi-X users represent state health departments (38%), local health departments (37%), CDC and other federal agencies (22%), and other organizations, such as poison control centers (3%).6

Through Epi-X, these users report outbreaks and other public health events to CDC and receive notifications about developing health threats through daily ele

ctronic summaries. When a report is of special importance, users receive immediate e-mails or emergency notification (i.e., pager, “land line” phone, or cell phone).

Enhancing disease surveillance systems. Epidemiologists need health-related data to detect disease patterns, estimate effects, and determine the spread of illness. Surveillance-the ongoing and systematic collection, analysis, and interpretation of data-is critical to detect disease outbreaks as early as possible and to ensure that public health professionals are aware of the number and geographic distribution of illness.

Table 3: Public Health Workforce for Disease Detection and Investigation, 2001-2006

Indicator Then (2001) Now (2006) Percent Increase
Epidemiologists in public health departments working in emergency response1 115 232 102%
Epi-X users2 890 4,646 422%
1 CSTE, ECA; 2006 - data for 38 states and DC; 2 CDC Epi-X data; 2006
5 CSTE, Epidemiological Capacity Assessment (ECA); 2006 – data for 50 states, DC, and 4 territories
6 CDC, Epi-X data; 2007

To help detect disease patterns, all state public health departments now can receive urgent disease reports 24/7/365 (Table 4). Previously, it was often difficult for clinicians to reach a public health professional after regular work hours.

In addition, CDC, state and local public health departments, and other partners are developing flexible and innovative surveillance systems for a wide range of emergencies, including disease outbreaks, bioterrorism, and natural disasters. In 2007, 44 states reported evaluating health data to detect unusual patterns that could be associated with health threats.7

The CDC Early Aberration Reporting System (EARS) is one surveillance system state and local health departments use to monitor notifiable diseases and detect unusual spikes indicating disease outbreaks. EARS tracks data from sources such as hospital emergency departments, 911 emergency calls, and school absenteeism. In 2007, EARS was used in approximately 100 state and local public health departments and international sites. It has been used during hurricane seasons and at several national events.8

Another surveillance system that CDC administers is BioSense, which provides local, state, and federal public health and healthcare organizations with access to the same data, at the same time. In other words, if an emergency occurs, every level of public health will be able to see healthcare data from their community in near real-time. This can decrease delays in recognition of a problem and enhance emergency response. As of November 2007, BioSense had 423 hospitals transmitting real-time data, covering 38 states and 71 major metropolitan areas. Over 1,500 federal military and veterans’ outpatient facilities also transmitted data.9

In preparation for a possible influenza pandemic, states are also improving systems to monitor seasonal influenza. In 2006, 28 states reported conducting surveillance for seasonal influenza throughout the year, while in 2007, all states and DC reported doing so.10, 11 Routine surveillance of influenza viruses can characterize circulating strains to help experts develop annual vaccines and identify strains with pandemic potential.

Challenges for Disease Detection and Investigation

Several challenges continue to hinder public health departments’ ability to collect and effectively use information.

Shortages in the epidemiology workforce. Public health departments still face barriers in recruiting and retaining qualified epidemiologists. According to the 2006 CSTE survey, most state and local public health departments reported difficulty in hiring epidemiologists. Although the number of epidemiologists has increased since 2001, in 2006, state public health departments reported needing 34% more epidemiologists than they had to provide full capacity nationwide.12

Other public health professionals, such as information technology specialists, are also needed to support emerging data sharing and communication initiatives. The aging public health workforce, high retirement rates, barriers to recruitment and retention, and the need to train the existing workforce in new methods and technology are all issues needing continuous attention.

Table 4: Public Health Disease Reporting Systems, 50 States and DC, 1999-2005

Indicator Then (1999) Now (2005) Percent Increase
Public health departments that can receive urgent disease reports 24/7/365 121 512 325%
1 HHS, Office of the Inspector General (OIG), Status of State 24/7 Urgent Disease and Public Health Emergency Reporting Systems; published February 2005; 1999 data; 2CDC, DSLR data; 2005
7 CDC, DSLR Mid-Year Report Review data; 2007
8 CDC, Division of Bioterrorism Preparedness and Response (DBPR) EARS data; 2007
9 CDC, Division of Integrated Surveillance Systems and Services BioSense data; 2007
10 CDC, Pandemic Influenza State Self-Assessments data; 2006 - data presented for 49 states
11 HHS OIG, Memorandum Report—Laboratory Preparedness for Pandemic Influenza; published October 2007
12 CSTE, ECA; 2006

Networking disease surveillance systems. During emergencies, public health professionals need to alert both clinicians and the public quickly. A unified network of surveillance systems from hospital organizations, physician practices, public health departments, and other data sources can provide public health professionals with the best available information to protect community health.

Epidemiologists and other public health professionals help protect population health after a chlorine spill.

Although public health departments have made progress in disease surveillance, more work needs to be done to integrate these systems. In 2007, 16 states did not report any plans to electronically exchange health data with regional health information organizations (networks of healthcare provider organizations that allow the electronic sharing of health information among members).13

In addition, quickly sharing public health information across jurisdictions is important during emergencies, such as when displaced individuals need care out-of-state. Without ensuring an appropriate legal framework before a disaster occurs, states may be unable to provide critical public health information to other jurisdictions.

SC train

South Carolina Public Health Effectively Responds to a Chlorine Spill

In January 2005, a freight train transporting chlorine and other chemicals collided with a parked train in downtown Graniteville, South Carolina. The rupture of one car released about 63 tons of liquid chlorine near residential and commercial districts. This accident caused nine deaths and forced at least 529 people to seek medical treatment. Local public health and emergency management officials investigated the damage. Since chlorine exposure was a serious public health threat, area residents were evacuated. Schools and businesses were closed.

Public health professionals coordinated emergency medical services, monitored hospital care, assessed the number of casualties, and supported disaster mortuary services. Through interviews and medical chart reviews, epidemiologists collected data on symptoms, exposures, and demographics. With this information, public health professionals could track and alleviate the long-term effects.

This accident was the worst chemical train wreck in the United States since 1978. Established response plans and partnerships helped South Carolina public health professionals respond quickly and effectively. The cooperative agreement helped fund activities that improved response. Because many nuclear and industrial facilities and rail lines were in the area, local public health and emergency management departments had taken an all-hazards approach to emergency response planning, with a focus on hazardous materials training. Coordination among agencies was also a priority.

Please refer to Section 2 for response examples for each state and directly funded locality.



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