Investigation Update on the ms Amsterdam

Cruise Line: Holland America Line

Cruise Ship: ms Amsterdam

Voyage Dates: 12/02–12/23

Number of passengers who have reported being ill during the voyage out of total number of passengers: 56 of 1317 (4.25%)

Number of ill crew who have reported being ill during the voyage out of total number of crew: 8 of 610 (1.31%)

Predominant symptoms: diarrhea and vomiting

Actions: In response to the outbreak, Holland America Line and the crew onboard the ship took the following actions:

• Increased cleaning and disinfection according to their outbreak prevention and response plans
• Made announcements to notify passengers and encourage case reporting
• Made the required initial notification report to CDC Vessel Sanitation Program and continue to make daily updates
• Collected clinical specimens from passenger and crew cases to be submitted to CDC laboratories for analysis

For the voyage following the outbreak, the case counts returned to expected levels.