A gastroenteritis outbreak due to Norovirus associated with a Colorado hotel.

* Norovirus is spread from one infected person to another by direct contact; aerosol; or contaminated objects, food, or water.

* A low infectious dose facilitates rapid spread of the disease.

* Although the virus does not replicate in food, in water, or on environmental surfaces, it is extremely persistent in these situations.

* Of 348 norovirus outbreaks reported to CDC between 1996 and 2000,

-- food was implicated in 39 percent, --person-to-person contact in 12 percent, and--water in 3 percent.

* In 18 percent no transmission route was identified.

* On May 24, 2000, a hotel notified Tri-County Health Department (TCHD) in Englewood, Colorado, that numerous individuals attending two professional meetings had become ill.

* The attendees complained of nausea, vomiting, and diarrhea.

* The investigation found three areas of concern:

-- food-handling practices, --food handler perceptions, and --hotel policies.

* The executive chef was not knowledgeable about basic principles of food safety.

* According to the kitchen manager, the hotel corporation did not require any food safety training.

* Several critical violations were observed ill the kitchen over the course of the investigation.

* Employees used knives for multiple tasks without cleaning and sanitizing them after each use.

* These tasks included the preparation of both raw meat and ready to-eat products.

* Buckets storing wet wiping cloths for sanitizing in-place food equipment did not contain ally measurable chlorine or quaternary ammonia residual.

* Employees who engaged in food preparation did not wash their hands between glove changes and used gloves for multiple tasks.

* Although employees did wear gloves during meal preparation, there was bare-hand contact with some produce such as lettuce and tomatoes.

* Lettuce was not washed prior to service.

* Also, language barriers between employees and management might have hampered communication in areas such as food safety education.

* The laboratory investigation confirmed norovirus as the agent in the outbreak.

* No specific vehicle of transmission was identified, however.

* Local health departments play a meaningful role in educating food establishments about the prevention of foodborne illnesses.

* Education alone, however, does not always result in application of the knowledge gained.

* Food safety practices often are sustained only for a short time,

* This phenomenon may result from natural "set points" that cause the system to revert to its original food-handling pattern as a result of underlying circumstances.

* Thus, health departments should first understand the particular food safety barriers within an establishment.

* After the barriers and supporting circumstances at the Colorado hotel were identified, training was designed to address the needs of the establishment.

* All kitchen staff received hands-on training.

* On subsequent visits to the kitchen, the health department required staff to demonstrate their food safety knowledge.

* Recommendations were provided for refining the hotel's food safety policies and training procedures.

* TCHD continued to monitor closely the hotel's food-handling practices to reinforce educational messages.