It's not good news for the human population. About 12 million worldwide die from the virus and they are not much closer to the cure.
Alan Krumwiede (Jude Law) contracts what he thinks is the virus and takes to his blog. Believing it is a strain of syphillus he takes a herbal remedy ... and lives. Riots start in the US with people desperate to get their hands on this, and the Government not seeming to do anything about pushing it through for major testing.
Kate Winslett keeps plugging away until she contracts the disease and soon enough is another casualty.
Meanwhile one of the medical researchers travels to Hong Kong to track down the history of the virus, and determines that it is a strain of pig flu mixed with bat flu. She is kidnapped by her guide, who wants to hold her for ransom until the cure comes out so his Chinese village, which has been decimated, will not be forgotten by the West.
Days pass by, and finally they have a successful trial on a monkey using vaccine #57. It is rushed through for trials, but still takes 90 days to be released. So we skip forward three months. Terror has gripped the streets and no one bothers to go to work except medical staff, the army ... and it seems mobile phone engineers.
Alan is not convinced on the merits of this new government-backed drug and is determined to tell all his followers not to take it. To prevent further deaths he is apprehanded before he can do any damage. They test him - and find that he didn't have the disease after all but just a regular cold.
To handle the numbers who now need the vaccine, the US holds a lottery by birthdays. Those unlucky to not be picked need to wait until the next batch is developed. Dr Ellis Cheever is handed two vials - he gives one to his wife, and the other to the son of the caretaker in a noble act.
The Chinese team phone in a ransom on the medical researcher and she is taken to the airport in exchange for a container of vials. Suffering from an acute case of Stockholm Syndrome, she learns later that they were just placebo drugs, so she runs off to the streets to warn her captors.
As it ends, Mitch finds his wife's camera and looks through the pictures - which recounts the story that she was "patient zero". A bat was moved by bulldozers and drops a bit of banana into a pig pen, which is eaten by the pig, before the pig is butchered ... and the chef doesn't bother to wipe his bloody hands before meeting Beth (Gwyneth Paltrow) at the restaurant.