Swine flu, the first flu pandemic of the 21st century, has been less deadly than feared since it emerged this year but has taken an unusually high toll among the world's young, leaving thousands dead.
The A(H1N1) virus was identified for the first time at the end of March in Mexico and quickly spread, with the World Health Organisation declaring a global pandemic on June 11.
The WHO estimated that by early December the global death toll had passed 9,500 but experts warned that it was too early to give an accurate estimate.
The world was mobilised into action with vaccination and awareness campaigns.
China, for example, had vaccinated more than 31 million people against the virus by early December with the aim of reaching up to 65 million by the end of the year.
"It is the first time that we have dealt with such a problem at a global level," said Sylvie Briand, a doctor who heads the WHO's Global Influenza Programme.
"This mobilisation has mainly allowed use to put vaccines in place in record time," she said.
The WHO has also recommended the use of the drug Tamiflu in high-risk swine flu patients to reduce and prevent complications and even death.
Two-thirds of Canada's roughly 200 fatal cases this winter had an underlying chronic illness such as asthma, cardiac disease, immunosuppression and diabetes, the world body has said.