Investigation Update on the Silver Shadow

Cruise Line: Silversea Cruises

Cruise Ship: Silver Shadow

Voyage Dates: May 10–24, 2018

Number of passengers who have reported being ill during the voyage out of total number of passengers onboard: 28 of 327 (8.56%)

Number of crew who have reported being ill during the voyage out of total number of crew onboard: 8 of 290 (2.76%)

Predominant symptoms: vomiting, diarrhea

Causative agent: norovirus

Actions: In response to the outbreak, Silversea Cruises and the crew aboard the ship reported the following actions:

• Increasing cleaning and disinfection procedures according to their outbreak prevention and response plan.
• Collecting clinical specimens from passenger and crew gastrointestinal illness cases for testing by CDC.
• Making twice-daily reports of gastrointestinal illness cases to VSP.

A CDC Vessel Sanitation Program epidemiologist will travel to Seward, Alaska, to meet the ship in port on May 24, 2018, to conduct an epidemiologic investigation and monitor the ship’s sanitation procedures. Specimens have been collected and will be sent to CDC for testing to determine the causative agent for this outbreak.

Note: The gastrointestinal illness cases reported are totals for the entire voyage and do not represent the number of active (symptomatic) gastrointestinal cases at any given port of call or at disembarkation.