Sep 20, 2010 (CIDRAP News) The US Centers for Disease Control and Prevention (CDC) recently issued new guidance for preventing flu in healthcare settings that reflects a year's worth of new information about the 2009 H1N1 virus and recommends surgical masks rather than N-95 respirators when providing routine care for flu patients.
Last year when the CDC issued a new set of recommendations for preventing the pandemic virus in healthcare settings, it said it would update the guidance as new information became available. In the middle of June the CDC previewed the change to its personal protective equipment (PPE) recommendation when it asked the public to comment on the proposed guidance. At that time, members of some healthcare groups, such as the Society for Healthcare Epidemiology of America (SHEA) said they were pleased by the new mask recommendation and its focus on the latest scientific data.
The CDC said the newest version of the 17-page guidelines for seasonal flu takes into account the wide availability of a trivalent seasonal flu vaccine that includes the 2009 H1N1 virus, which the CDC expects to see again during the upcoming flu season.
Other new information that triggered the update includes more certain estimates of hospitalizations and deaths from the 2009 H1N1 virus and new data that suggest face masks and hand hygiene practices can reduce the risk of flu in homes and healthcare settings.
Previous CDC pandemic flu prevention guidance for healthcare settings has recommended N-95 respirators for protecting workers who care for flu patients, but the advice has been controversial. Some professional groups have opposed their routine use because efficacy has been inconclusive and employees have said the N-95s are uncomfortable to wear for long periods.
An unpublished study by Australian researchers last September found that respirators may be better than masks at protecting healthcare workers, though the difference may not be significant. However, an October 2009 Canadian study of flu in nurses suggested that masks weren't inferior to N-95 respirators. A study in January showed that surgical masks and hand hygiene reduced flulike illnesses in the college setting, and while some experts said the findings seemed to support the view that masks are sufficient for routine healthcare tasks, they cautioned about generalizing the results to the community at large.
When pressed by some health groups last fall about the N-95 recommendation, federal health officials said they were swayed by the unique pandemic flu conditions, such as low levels of population immunity, late and scarce availability of a vaccine targeted to the virus, and increased exposure of healthcare workers to the new virus.
Dr John Jernigan, a medical epidemiologist with the CDC who was involved with developing the new guidance, told CIDRAP News that as the face of the 2009 H1N1 virus looks more and more like seasonal flu, changes in the new guidance emphasize droplet precautions in the context of a multifaceted flu prevention approach. "PPE is likely to be one of the least effective methods, with vaccination being most important," he said.
He said the new guidelines emphasize identifying flu patients early and applying engineering and environmental prevention strategies, as well as appropriately managing sick healthcare workers. Health facilities need robust programs to discourage healthcare workers from coming to work sick, Jernigan added.
Dr Jeff Hageman, an epidemiologist with the CDC who also helped develop the guidance, said a major change for seasonal flu prevention in health settings involves the recommendations for PPE and other devices during high-risk activities such as aerosol-generating procedures. Though not all facilities have negative-pressure rooms or devices, a topic covered in the new guidance, the recommendation to use N-95s and eye protection during the procedures should be feasible for all situations, he said.
Jernigan said the CDC received numerous and varied comments on the draft guidance while it was open for public comment this summer. However, he said there was a general level of support for the new changes. He added that new data on PPE protection that were published over the summer didn't suggest that one form was superior to another.
In addition, Hageman said that putting together the new guidelines showed a continuing need for more research. "There is a lack of data to definitively say which modes are more important," he said.
Though some medical groups such as SHEA, the Infectious Diseases Society of America, and the American Academy of Pediatrics have recently issued statements supporting mandatory flu immunization for healthcare workers, the CDC guidance stops short of recommending the measure.
Instead, it highlights the elements of programs that can successfully raise healthcare worker vaccination rates, such as providing incentives, offering free vaccine, having a systematic approach, and disseminating clear and timely communication on the topic.
Jernigan said the purpose of the guidelines is to emphasize the importance of vaccination and the practices that are likely to result in high coverage levels. The CDC's Advisory Committee on Immunization Practices (ACIP) is expected to address the topic next June, and he added that the new document probably isn't the right springboard for taking a step toward recommending mandatory vaccination.
Hageman added that one of the challenges in producing the flu prevention guidelines is making them relevant across a spectrum of healthcare settings and giving professionals enough leeway to, for example, decide what methods work best in each setting to boost vaccination rates. He said that if current approaches are successful, there is no need to change them.
The CDC again included the caveat that its guidance will change as it receives new information.
Updated guidance still includes detailed recommendations for periods of increased flu activity, such as segregating patients with suspected flu who present for care and minimizing visits from patients with mild flulike symptoms who aren't at increased risk of complications by, for example, offering a flu telephone consultation line.
In the section on workers who develop fever and respiratory symptoms, the updated guidance retains the recommendation that they should stay home until they have been fever-free without the use of fever-reducing medications for 24 hours.
The CDC recommends that healthcare workers who are still coughing and sneezing wear a facemask during patient care. More stringent measures are recommended when treating high-risk patients such as those undergoing stem-cell transplants.
Jun 23 CIDRAP News story "CDC proposes new flu guidance for healthcare facilities"
Oct 14, 2009, CIDRAP News story "CDC keeps N-95 recommendation in health worker guidance"
Jan 22 CIDRAP News story "Masks plus hand hygiene reduced ILI in college dorm study"
Oct 2, 2009, CIDRAP News story "Study suggests masks rival respirators for flu protection"
Nov 10, 2009, CIDRAP News story "NIOSH says disputed study didn't guide advice on masks"