Super Sleuths
Nurse epidemiologists are on the frontlines of mysterious disease outbreaks– assessing trends, trying to find the cause, and developing interventions

By Heather World
April 20, 2004

Kirsten Ernst, RN, MSN, MPH, FNP, had been on the job at the national Centers for Disease Control and Prevention only four days when her pager rang on a Friday night in August 2000. The next morning, she found herself on a plane to Jackson, Miss., off to track down the West Nile virus.

As an epidemic intelligence service officer at the CDC, Ernst helps local officials tackle diseases that are often deadly and mysterious. Mississippi had been especially hard hit by West Nile that summer, and it took investigators six weeks to conclude the source of the disease as well as create a plan to combat it.

Not all nurse epidemiologists find themselves on a plane at a moment’s notice, but all are detectives tracking diseases—both infectious and noninfectious—assessing trends, looking for causes, and developing interventions on a primary and secondary level.

Although physician epidemiologists may focus on the pathology of a disease, nurse epidemiologists investigate the community’s habits to see how it spreads and how it can be contained.

Epidemiologists such as Maria Teran-Maciver, RN, MSN, a community involvement specialist at the CDC, study demographics and the dynamics of a community: Does the community meet in churches? How much local cable do its people watch?

“In the South, you never have a public meeting on Wednesday because that’s church night,” she said.

Nurse epidemiologists assess and treat communities in the same way they once helped individual patients, said Ann Kurth, RN, PhD, CNM, an assistant professor in biobehavioral nursing and health systems at the University of Washington in Seattle.

“It’s such a natural fit for a nurse to do epidemiology,” she said. “It’s part of what we do in our day-to-day care. But now the population is your patient.”

Most epidemiologists train by getting a master’s degree in public health with a focus on epidemiology or by getting a doctorate in epidemiology, Kurth said. They enter into one of the overlapping subfields of epidemiology: chronic disease, environmental, occupational, infectious disease, or social and behavioral. Some work to control infectious outbreaks in hospitals, others work in state public health departments.

Specific numbers of nurses working as epidemiologists are hard to find, but of the country’s 2.2 million working nurses, about 12.8% work in community and public health, and 1.7% work in occupational health. A small percentage of those are nurse epidemiologists.

As an environmental epidemiologist, Ernst has studied the effects of a range of events, from air quality in New York after the collapse of the World Trade Center to the effects of the smallpox vaccine.

“The environment affects everything,” she said. “There’s a lot of overlap.”

In Mississippi, she and her colleagues identified patients with West Nile, tested them, and reviewed the data. Next, they sought a “control” group that had not been infected. Comparisons between the groups confirmed that mosquito bites spread the disease. The next step was to educate the public about preventing bites and reducing the mosquito population through spraying.

Caring for communities

Identifying and solving a problem within a community involves coordination among many disciplines.

“You’re working at a federal, state, and local level, with the EPA, environmentalists, physicians, community concerns groups, microbiologists,” Ernst said. “And you’re meeting one-on-one with citizens.”

Each group brings its own strengths to the team. Nurses bring trust with the public, Ernst said. “You’ve got a foot in the door,” she said.

Communities also rely on nurse epidemiologists for information in the same way patients at a clinic would look to their nurses for education. Teran-Maciver works for the CDC’s Agency for Toxic Substances and Disease Registry, which investigates communities near hazardous waste sites that have been put on a national priority list.

In 1999, she flew to Libby, Mont., where a high proportion of residents was dying of lung problems. The Environmental Protection Agency had discovered asbestos in the air from a mine that had closed, and Teran-Maciver’s team’s job was to alert residents, present and former, to come in for testing as well as to disseminate information about the problems.

National media helped spread the word about testing, but her team also went door-to-door, held meetings at senior citizens centers, schools, and the Veterans of Foreign Wars meeting sites.

Sending a letter to everyone in town is not enough, Teran-Maciver said. Health officials must repeat the message often before people hear it. Later, her group handed out pamphlets and set up counseling sessions for people diagnosed with asbestosis, a fibrosis or scarring of the lung tissue due to asbestos exposure.

“A lot of people thought if they were diagnosed with asbestosis that was a death warrant, but we wanted them to know there were ways they could take care of themselves and live a fairly healthy life,” she said.

Her group distributed a fact sheet that advised patients to drink plenty of fluids (to keep secretions loose and incapable of blocking airways), to exercise (to build lung capacity), and to see a doctor regularly.

In the field

Not all outbreaks garner national media attention or require the aid of the CDC. Many nurse epidemiologists can be found in state health departments.

Neil Pascoe, RN, BS, CIC, works for the Texas Department of Health, Infectious Disease Epidemiology and Surveillance division. Two years ago, he was called to investigate an outbreak of methicillin-resistant Staphylococcus aureus among cadets at a police training academy. About 43 of the 110-member class suffered soft-tissue infections, and two had bloodstream infections.

MRSA can kill, so administrators were eager for the state to discover the problem, though not so eager to spend the time getting to its root. Nevertheless, Pascoe and his colleagues looked at all aspects of the police training academy. They watched cadets wielding knives and guns, and subduing “violent suspects.” They inspected locker rooms and laundry facilities.

Pascoe learned that recruits sometimes were injured while training for defensive tactics. The recruits passed around protective equipment without sanitizing it, passing along the infection. Clothes were laundered in water that wasn’t hot enough to kill infections.

Pascoe and his colleagues set up measures to combat the infection: They recommended the laundry be washed in bleach and hotter water; they instituted handwashing measures and placed bottles of alcohol-based sanitizer around the facility. Eventually, the spread of MRSA stopped.

Pascoe is one thesis short of a master’s degree in public health, but much of his experience comes from working as a nurse. He has worked in med/surg, burn and surgical ICU units in hospitals, in home health, in a jail, in a long-term rehab for head-injured patients, and in a neuro intensive care unit.

His role at the state health department means he spends a lot of time using what he has learned to stop infections in various settings to teach others.

“I talk about specific practices they can do in their environment,” he said. He gives talks to jail administrators and nurses who work at schools. He also does television interviews and puts information on the state’s website.

“I tell as many people as possible about respiratory hygiene and hand hygiene every chance I get,” he said.

Pascoe, who wears a sanitizer on his belt so he can “walk the talk,” admits he may be a little different from most people.

“I’m probably a little more compulsive than others because I hear the stories,” he said.

Yet he hasn’t missed a day of work due to illness in more than two years, despite spending plenty of time with his seven grandchildren and with sick people in the community.

Anticipate and prevent

Education plays a big role in the job of nurse epidemiologists in hospitals, too. Joan Golden, RN, CIC, supervises infection control at three hospitals in Provo, Utah.

Her biggest job is to prevent infections that occur after a patient enters the hospital. Hospitals are in a double bind when it comes to infection. Often, patients arrive sick and weak, and once inside the hospital, their bodies are opened up and filled with foreign objects.

All of these factors increase the chance of infection.

Golden examines the numerous processes within the hospital. She compiles statistics, tracks infections, creates policies to prevent infections, and educates staff.

“I think infection control 24-7,” she said. “I am infection control.”

The biggest culprits of infection in a hospital are aspiration, tubing contamination (both caused by the patient’s own body), and the hands of caregivers, she said.

A cluster of infections might point toward hospital procedure as the root of the problem, which leads to “fingerprinting” of the organisms, which may lead to an outbreak investigation.

Sometimes, a source cannot be found, she said.

“Magically, infections go down and you may not be able to determine a cause at all,” she said. Other times, something as simple as contaminated water or a product recall is behind the outbreak.

Golden does not wait for outbreaks to institute infection control measures. She has implemented silver-coated catheter lines to cut down on catheter-associated urinary tract infections. She has encouraged the use of alcohol hand sanitizers and chlorhexidine gluconate for skin prep. She asks health care workers inserting lines to wear masks, as advised by the CDC.

Since the terrorist attacks of 2001, many hospital infection control specialists also have played a role in developing plans for bioterrorist attacks.

Golden works in teams that include employees of state health departments, emergency response services, and other hospitals.

This spring, the local health department will have a mock outbreak of hepatitis A, she said. The hospital will help orchestrate the administration of a real vaccine to see how fast a prophylactic vaccine can be disseminated to the population.

Golden’s nursing background helps her in her job with infection control, she said.

“The nurse is probably more in tune to hospital policy development and compliance,” Golden said. “The physician might be more in tune with a disease and its process.”

Kurth would like to see more programs that educate nurses in epidemiology like the two her university offers. Kurth said the University of Washington is the only program in the country that offers a master’s degree for infectious disease and infection nursing control.

“I think we’re playing catch-up with infrastructure to meet that need,” she said.

The specialty has no formal learning track, and a recent increase in emerging and reemerging infectious diseases will make the field all the more important, Kurth said.

“We need more options for training,” she said. “Infectious diseases are not going away. Nature will keep throwing these things at us.”

Contact Heather World at h_world@yahoo.com.