Norovirus Outbreak Forces Lockdown on Ruby Princess Near San Francisco

A norovirus outbreak on the Ruby Princess during a 20‑day Alaska cruise prompted a lockdown in San Francisco, with more than 100 passengers and 20 crew affected. Princess Cruises says it implemented enhanced sanitation, isolated the ill, collected stool samples for testing, and is conducting thorough cleaning ahead of the next voyage, under CDC Vessel Sanitation Program oversight. Norovirus is a common cause of GI illness on cruise ships, often prompting ship-wide sanitation and isolation measures.