Marilyn Roberts

Professor Marilyn Roberts was contacted by firefighters who were concerned about potential occupational exposures.
Photo: Yuen Li

Snohomish County Fire District 1 in Washington state comprises 12 fire stations that field, on average, 13,000 emergency calls each year. As wellness coordinator for District 1, firefighter and paramedic Kevin Fetter was interested in a new disinfection system. But first he wanted to find out what kinds of germs were on the surfaces of the fire stations and medic units and which could be transmitted to personnel that might potentially cause infection or illness.

Fetter called labs all over the country, and he found help at the UW, where he connected with Professor Marilyn Roberts, an environmental microbiologist in our department. Their collaboration led to the first-ever environmental health study on methicillin-resistant Staphylococcus aureus (MRSA) in Northwest fire stations and on fire personnel to determine the extent of contamination. The study's findings led to a number of protocol changes to improve decontamination of environmental surfaces inside the fire stations and trucks.

In the last 10 years, the number of hospital- and community-acquired MRSA infections—those often contracted in schools, public gyms, and workplaces—has risen. MRSA can be transmitted from surfaces to people and from person to person. The increase in incidence has led to concern for first responders, including police, firefighters, and emergency medical personnel. Because fire personnel interact with both hospital and community populations, they have the potential to be exposed to MRSA as part of their daily duties.

"Firefighters and paramedics are at the crossroads between the public and hospital environments," said Roberts. "Their job includes administering first-response care to patients, many of whom are more likely to be MRSA carriers or have MRSA infections than the general population. This may put fire personnel at increased risk for MRSA infections."

Roberts found MRSA in four percent of more than 1,000 samples collected from surfaces inside medic and fire trucks and two fire stations, including the garage, firefighter outer protective gear, and living quarters. Both hospital- and community-acquired MRSA organisms were found.

Fetter and colleagues knew that MRSA was being studied in hospital settings, but didn't know how MRSA affected fire personnel. Except for one study in Arizona, no one else had looked at MRSA in fire stations and at firefighter exposure. "We now recognize it as a problem," said Fetter, referring to the firefighter community.

Dirty Handed!

Results of the study became part of an educational campaign, which included posted signs reminding personnel to wash their hands to prevent infection.
Photo: Courtesy of Snohomish Co. Fire District 1

Roberts' research team found more than 20 percent of the fire personnel who volunteered to be tested had MRSA in their nose. The study did not determine how long the MRSA had been there. The potential risk of a carrier developing an infection from having MRSA in the nose is not clear, but many people are colonized with MRSA prior to infection. By genetically characterizing the different organisms collected, Roberts found that most of the MRSA strains carried by the fire personnel were related to the MRSA strains found in the stations and trucks, suggesting transmission between personnel and environmental surfaces is occurring.

Roberts and her team determined which locations in the stations and trucks were most likely to be contaminated. And to better prevent bacteria from contaminating surfaces, protocol changes were proposed, such as lengthening how long disinfectants are left on surfaces before being wiped off; changing sanitizers and hand-towel dispensers to the touchless variety; and purchasing new station furniture made of easy-to-clean plastic or wood rather than furniture covered in fabric.

Fetter helped develop and distribute educational materials on best practices for disinfection, including signs reminding personnel to wash their hands, bandage wounds, and seek medical attention if a skin rash or red spot does not improve in a few days.

The UW study results have attracted attention in other regional fire departments because findings showed firefighters can be MRSA carriers. Roberts said she hopes to expand the study to determine if the results from the initial study are representative of the larger firefighter population within Washington state and throughout the United States.

The project was supported by a Washington State Department of Labor & Industries' Safety & Health Investment Project (SHIP) grant and the Snohomish County Fire District 1.

For further reading

MRSA Exposure and Firefighters.