Some cases of swine influenza, notably in Mexico, are being transmitted between people; about twenty people have died. This is important because flu from other animals tends to make people sicker. If it’s easy to catch and hard on people, it might spread around the world with travellers.
Some people in the U.S. have become sick and a few in Montreal, Quebec, Canada.
The American Center for Disease Control (CDC) and the World Health Organization (WHO) have been watching very carefully. They say:
Swine Influenza (swine flu) is a respiratory disease of pigs caused by type A influenza…
From December 2005 through February 2009, a total of 12 human infections with swine influenza were reported from 10 states in the United States. Since March 2009, a number of confirmed human cases of a new strain of swine influenza A (H1N1) virus infection in California, Texas, and Mexico have been identified… See Human Swine Flu Investigation.
The current vaccine does not protect against the virus, which has components from human, avian, North American swine, and Eurasian swine flus.
(Image from this Chemistry course)
If vaccine needs to be manufactured, it will take a few months to get the right strain. And the world’s capacity for making flu shots is only about 400,000 to 500,000 doses.
There was a previous swine flu scare in 1976.