Hepatitis A in a food worker and subsequent prophylaxis of restaurant patrons.

* CDC has estimated that 38,000 cases of acute hepatitis A occurred in 2002 in the United States.

* 8,795 acute cases were reported.

* A laboratory-confirmed hepatitis A patient was reported to Tri-County Health Department (TCHD) in Colorado on December 30, 2002.

* The individual with the case was determined to be an employee of a fast-food restaurant.

* TCHD conducted an environmental investigation of the restaurant and identified handwashing deficiencies.

* The restaurant manager reported that the ill employee had worked while infectious, had had frequent contact with ready-to-eat foods without gloves, and had not practiced proper hand hygiene.

* TCHD staff decided to hold a mass immunoprophylaxis clinic.

* A news release was issued advising restaurant patrons to get an immune globulin (IG) shot at the clinic.

* A total of 693 people received IG at the TCHD clinic.

* The clinic screened an additional 195 individuals who were determined to be ineligible to receive IG.

* All employees of the restaurant either received IG or were removed from the work schedule for the following 50 days.

* TCHD's Health Alert Network was used to fax a hepatitis A advisory to physicians informing them of potential exposure dates, symptoms, laboratory tests, and treatment for hepatitis A.

* Follow-up inspections of the restaurant were conducted over the next six weeks.

* No additional restaurant employees were ill, and no additional reported cases of hepatitis A were associated with the ill employee.

* The financial cost of holding the clinic totaled $48,300, or $69.70 per vaccine.

* All expenses were recovered from the restaurant corporation.

* Effective hepatitis A vaccine has been available in the United States since 1995.

* A substantial reduction in disease incidence has occurred in recent years.

* Currently, CDC's Advisory Committee on Immunization Practices (ACIP) recommends considering hepatitis A vaccine if health authorities or private employers deem it cost-effective.

* An economic analysis has determined that routine vaccination of restaurant workers may not be economical either from the perspective of the restaurant owner or from a societal perspective.

* The vaccine would prevent infection from only one of many enteric agents.

* Employers who want to reduce the risk of hepatitis A infection among employees, however, should focus on providing vaccine to people with risk factors for infection:

-- men who have sex with men,

-- illicit-drug users, and

-- people who travel to developing countries.

* Ultimately, the most cost-effective means of preventing foodborne illness is proper food preparation and good hand hygiene.