These voyages stand out for the particularly high percentages of ill passengers onboard, but the cases give no further insights into how to stop outbreaks from happening in the future.
There have been multiple norovirus outbreaks on cruise ships over the last month, but how big of a concern is this for potential cruisers?
In the past ten years, only nine cruise virus outbreaks have caused more than 20 percent of passengers to become ill. This according to data reported the CDC.
There were only 63 passengers onboard which explains the high percentage, but no other outbreak in the past twenty years has crossed the 30 percent threshold in that time period.
There were less than 150 passengers onboard during four of nine worst outbreaks, leading to shockingly high percentages.
However, it’s the outbreak was likely even more evident since passengers more easily noticed how many of their fellow cruisers became ill.
Two of the worst cruise ship outbreaks in the past decade happened onboard Celebrity Cruises Mercury.
Approximately 22 percent of passengers fell ill on the ship on two separate voyages in 2010. The first time 293 of 1,163 cruisers were reported ill on a 30-day journey. The second time 411 of 1,83 cruisers were reported ill on a 11-day trip.
Below is statistics on the nine cruisers where more than 20 percent of passengers fell ill during a virus outbreak:
|Year||Cruise Line||Ship||Cruisers Reported Ill (%)||Cruisers Reported Ill (#)||Total Cruisers (#)||Cause||Length of Voyage|
|2008||American Canadian Cruise Line||Grande Caribe||43%||29||68||Norovirus||12|
|2011||Lindblad Expeditions||National Geographic Sea Lion||28.87%||17||61||Unknown||7|
|2010||Fred Olsen Cruise Lines||Balmoral||25.19%||293||1163||Unknown||30|
|2007||Cruise West||Spirit of Nantucket||22.22%||8||36||Unknown||7|
|2005||Holland America Line||Ryndam||22.2%||272||1223||Norovirus||16|
|2014||Royal Caribbean Cruise Line||Explorer of the Seas||20.6%||634||3071||Unknown||10|
|2003||Windjammer Barefoot Cruises||Legacy||20.54%||22||107||Specimens not obtained||7|
Photo credit: The Royal Caribbean International's Explorer of the Seas is docked at Charlotte Amalie Harbor in St. Thomas, U. S. Virgin Islands, Sunday, Jan. 26, 2014. Thomas Layer / AP Photo