A norovirus outbreak occurred on a US luxury cruise ship with more than 2,000 people on board, and nearly 100 people have been infected

A norovirus outbreak broke out on the "Serenade of the Seas" owned by Royal Caribbean Cruises in the United States during a voyage from September 19 to October 2. Nearly 100 people on the ship were infected. The actual number of cases may have been underreported.As of October 1, 94 of the 1,874 passengers on board had developed typical symptoms of norovirus infection such as diarrhea and vomiting, and 4 of the 883 crew members were infected.

Norovirus is highly resistant to alcohol and common detergents, and is also highly contagious. Only 18 virus particles can cause infection. Patients usually develop symptoms within 12-48 hours after infection and can recover on their own within 1-3 days, but the detoxification period can last for more than 2 weeks.

The cruise ship departed from San Diego, California, and visited ports in Mexico, Costa Rica, Panama and Colombia.

The epidemic reached the 2% notification threshold (approximately 55 cases) stipulated by the U.S. Centers for Disease Control and Prevention (CDC) as early as September 28 (the ninth day of the voyage).However, passengers reported that the actual number of infections may be higher, as some concealed their symptoms for fear of being quarantined..

As a densely populated closed space, cruise ships have ventilation systems, public tableware, and frequently touched handrails and door handles that may become virus carriers.

When a similar outbreak occurred on another Royal Caribbean cruise ship, Navigator of the Seas, in July this year, most of the 141 infected people were infected through contact with contaminated surfaces.

also,Some passengers, fearing that being quarantined would affect their itinerary, chose to take their own medicine or conceal their symptoms, causing the virus to continue to spread without their knowledge..

An anonymous passenger revealed that at least 15 people on his floor had vomited, but only 3 reported it to the ship. This behavior not only increased the risk of infection for other passengers, but also interfered with the ship's epidemic control measures.