A Norwegian Cruise Line ship with 3,200 passengers and crew disembarked in New Orleans Sunday amid an onboard COVID-19 outbreak that includes a suspected case of the omicron coronavirus variant. So far, a total of 17 people who were aboard have tested positive.

The news raises concern that the outbreak could continue to grow and put those on land at further risk of the variant. Cruise ships are notorious for harboring outbreaks. At the dawn of the pandemic, several outbreaks at sea demonstrated just how easily the coronavirus can spread in such tightly packed and highly social vessels. And the omicron variant may be the most transmissible variant yet identified. Early data from South Africa suggests it could spread more than twice as quickly as the already hypertransmissible delta variant.