I'm very impressed at how effective this flu pandemic threat is at pacifying a population.

It takes between one and four days (average two days) to go from being infected to having the full symptoms. People with flu are usually infectious a day before symptoms start and remain infectious for approximately five days after the start of the flu symptoms. Children and people with lowered immune systems may remain infectious for longer. You should therefore try to avoid all unnecessary contact with others during the infectious period.

http://www.nhs.uk/Conditions/Flu/Pages/Introduction.aspx

Which is why public health officials are frantically performing contact tracing and surveillance to track where the outbreak is going. It is the best way to head off something worse and help society prepare.

The New York City Health Department sent Dr. Sara Josephine Baker to talk to Mary, but "by that time she was convinced that the law was wantonly persecuting her when she had done nothing wrong."<2> A few days later, Baker arrived at Mary's place of work with several police officers and took her into custody. The New York City health inspector investigated and found her to be a carrier. Using powers granted by sections 1169 and 1170 of the Greater New York Charter, Mallon was held in isolation for three years at a hospital located on North Brother Island. Eventually, a new health commissioner decided that Mallon could be freed from quarantine on condition that she agreed to no longer work as a cook and would take reasonable steps to prevent transmitting typhoid to others. Eager to regain her freedom, Mallon accepted these terms and conditions. On February 19, 1910 Mallon agreed that she "is prepared to change her occupation (that of cook), and will give assurance by affidavit that she will upon her release take such hygienic precautions as will protect those with whom she comes in contact, from infection". As a result, she was released from quarantine and returned to the mainland.

However, she had been given a job as a laundress, which paid lower wages than her previous occupation as a cook. Mallon concealed her true identity by adopting the pseudonym "Mary Brown", returned to her previous occupation as a cook, and in 1915 infected 25 people while working as a cook at New York's Sloane Hospital for Women; one of those infected died. Public health authorities again tracked down and arrested Mary Mallon, returning her to quarantine on the island. Mallon was confined there for the rest of her life. She became something of a minor celebrity, and was interviewed by journalists who were forbidden to accept as much as a glass of water from her. Later in life, she was allowed to work in the island's laboratory as a technician