Healthcare Infection Prevention

Halting LTC norovirus outbreak in eight days

ICP proves it can be done via aggressive measures

A norovirus outbreak can be notoriously difficult to control in a long-term care setting before it exacts a huge toll on residents and staff. However, rapid adoption of strict measures successfully kept the pathogen at bay while it was running rampant in a community outbreak, says Mary Webb, RN, BSN, MA, CIC, infection control and wound care professional at San Mateo (CA) Medical Center.

"[Our reaction] was immediate," she says. "The minute we had the second diarrhea we jumped on this without knowing [the etiologic agent]. I wanted to stop the spread of whatever was going on. I didn't know if it was somebody that had bad food or what. But when you work in long-term care, some things can spread very rapidly."

The emergence of two new strains of norovirus has resulted in increased reports of hospital and long-term care outbreaks, some of which appear to involve the first fatal infections with the virus reported in the United States, the Centers for Disease Control and Prevention reports.1

Beginning in October 2006, emergency department visits for acute gastroenteritis (AGE) nationally started increasing. For example, in New York state alone, 333 AGE outbreaks were reported from Oct. 1, 2006, through Jan. 31, 2007. That is more than four times the number reported during the same period in 2005-2006 (76 outbreaks), the CDC found. Of those outbreaks, 272 (82%) occurred in long-term care facilities and 26 (8%) in hospitals. Of 216 health care facility outbreaks (both hospitals and long-term care) with available data, a total of 7,907 patients and 4,317 staff members were affected. Of these, 207 (2.6%) patients and 20 (0.5%) staff members were hospitalized, and 16 deaths among patients with AGE were reported. In addition, two deaths in a Wisconsin nursing home were associated with AGE outbreaks in health care facilities. Illness compatible with norovirus infection also was the primary cause of death recorded for a resident of a long-term care facility in North Carolina.

In the San Mateo outbreak, it appears ongoing community transmission worked its way into the facility via visitors and staff members, Webb surmises.

"Two of our residents had visitors on a Sunday that came from an outside residential senior community that appeared to be having [an outbreak]," she says. "We implemented precautions right away, not knowing anything about [norovirus] and notified public health. We put our infection control guidelines out there very proactively and immediately."

Staff members who had been attending a family event may have brought it into the facility as well, she said, noting the outbreak peaked at 12 resident cases and 11 employee cases. "They hadn't been working when our patients were ill or even incubating, and some had been to a family event," she says.

Regardless, as aggressive control measures came into play, the outbreak was halted and the public health department lifted restrictions in eight days. The case numbers are small compared to many outbreaks, which can go for prolonged time periods. "It was in the one unit and it didn't cross over to the unit across the hall," Webb says. "It didn't go anywhere else because we just simply stopped it. If you worked in that unit you didn't move from that unit. The other [staff] were not allowed to come in. You've got to break the chain of transmission very early."

Steps to break the chain

Webb emphasizes that taking specific steps to prevent the virus from being transmitted from person to person can control outbreaks. Those include:

  • Limiting transmission when initial cases are suspected.
  1. Close doors to long-term care nursing unit.
  2. Notify medical director.
  3. Place the isolation station over the entrance door to the long-term care nursing unit (e.g., masks, gowns, gloves, hand hygiene supplies).
  4. Place "Do not Enter" signs on door to the long-term care nursing unit.
  5. Place isolation stations over door of each symptomatic resident room.
  6. Discontinue staff "floating."
  7. Ask family of symptomatic residents to avoid visitation.
  8. Notify public health, communicable disease, licensing and certification authorities.
  9. Begin line listing of residents who are symptomatic.
  • Instituting infection control measures without waiting for diagnostic confirmation.
  1. Do not admit to the unit.
  2. Do not discharge from the unit.
  3. Dedicate patient care equipment to a single resident or among symptomatic residents, adequate clean and disinfect before use for another resident.
  4. Exclude nonessential personnel from the affected unit.
  5. Clean hands before and after glove use.
  6. Wear gowns and change between each resident contact.
  7. Cancel or postpone group activities.
  8. Increase frequency of routine ward bathroom and toilet cleaning.
  9. Use EPA-approved disinfectant to disinfect surfaces.
  10. Consider antiemetics for patients with vomiting.
  11. Clean carpets and soft furnishing if contaminated.


  1. Centers for Disease Control and Prevention. Norovirus Activity — United States, 2006-2007. MMWR 2007; 56(33):842-846.