Passengers were told that "to minimise the risk of infection is to remain in your cabin on the ship", following advice from the Centres for Disease Control. And passengers have remained in their cabins since last Tuesday.
As a result of the quarantine, food has become an important part of existence for passengers. The passenger rations are a source not only of sustenance but of novelty and entertainment.
Drawing on his resilient sense of humour to keep cabin fever at bay, Smith began publishing mini reviews of the food brought to his door.
"Princess is stepping up its game" came one tweet with an accompanying image of his and his wife's meals. "Don't believe the honeymooners who would rather be in an American hospital. You might have to drag me off the ship when the quarantine ends."
The positive attitude was only slightly dented by the rationing of one important foodstuff: coffee.
Tweeting a picture of a handwritten note he had made for the crew, Smith wrote "PLEASE CAN WE HAVE MORE COFFEE?"
"This is the only plea for help I have on-board #DiamondPrincess Sorry/Not sorry," he wrote.
Not everyone was impressed by Smith's antics to combat boredom.
"I find your commentary insensitive and misleading. My parents are on the ship and do not share your seemingly charming experience," wrote Ashley Rhodes-Couter in response. "Ample praise to the crew and staff for all they are doing. We're hopeful for as many survivors as possible. People are suffering on board and ashore."
Some guests are also not having the same enjoyable experience.
"Passengers in the small inside cabins have no window, there is no daylight, and no fresh air," UK passenger David Abel wrote to Facebook, "But the captain has announced those passengers will be allowed access to open deck for exercise and fresh air."
Smith, whose cabin has a balcony, at least can have some window into the outside world.
He is able to watch curious civilian watercraft being kept at bay by the Japanese coastguard and on Sunday was able to take a picture of the sun setting over Yokohama.
The current sailing of the Diamond Princess was originally due to end on Wednesday, but as it stands, passengers will be held in quarantine for another week.
So far 69 passengers have tested positive for the potentially deadly virus, according to Princess Cruises. These passengers have been taken for treatment on the mainland.
Meanwhile, those who remain uninfected are confined to their rooms until at least next week.
While in quarantine, resupplying and restocking the ship is made difficult.
A spokesperson for Princess Cruises has told the Herald that regular services β such as catering and cleaning β have had to be adapted to the "extraordinary situation in Japan".
"Princess Cruises is drawing on 55 years of experience in looking after guests to adapt systems and processes to care for them in these extraordinary circumstances."
"The quarantine end date remains at February 19," said Princess Cruises in a statement.
Diamond Princess: Two weeks in quarantine
Princess President Jan Swartz issued an update over the weekend, having returned from Japan saying that the company had "shifted additional resources to Yokohama" to deal with the quarantine.
As well as doctors helping to test for and diagnose new cases, Swartz said their medical teams were being joined by "experts in mental health and pharmacy".
"We also have a dedicated phone line to support follow ups on prescriptions," she said, as many guests will be running low on personal medication with the quarantine extending the time at sea by a week. Passengers have made almost 2000 requests for prescription drugs and medications.
However mental wellbeing is also an important consideration. For passengers confined to limited quarters, keeping mentally active can be just as important for their wellbeing.
"We understand there are many dimensions of health, including the human need for social connection and keeping the mind active," said Swartz.