https://www.bloomberg.com/news/articles/2020-03-23/coronavirus-traces-lingered-in-vacated-cruise-cabins-for-17-days
Traces of new coronavirus were found on surfaces in cruise-ship cabins for as many as 17 days after passengers left, researchers said, though it wasn’t possible to determine whether they caused any infections.
Researchers looked at the rooms of infected passengers aboard the Diamond Princess, both those who showed symptoms and those who didn’t, according to a study Monday in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.
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A previous analysis found that the virus remained viable on plastic and stainless steel for up to three days, although levels fell dramatically over time. It was less stable on copper, where no viable virus was found after 4 hours, and cardboard, which was clean after 24 hours, according to the report in the New England Journal of Medicine.
The latest study looked at uncleaned rooms, but other research has found that cleaning the rooms of Covid-19 patients was highly effective at killing the virus.