Science and the Swine Flu

You’ve likely heard news reports this week about the swine flu virus outbreak in Mexico. The swine flu or swine influenza produces regular outbreaks of respiratory disease in pigs and is caused by influenza type A viruses. Transmission of swine flu viruses between people has been reported in the past, but was limited to three people. Today, the World Health Organization (WHO) raised its pandemic alert to "phase 5", which means that people in at least two countries in one WHO region are spreading the disease [1]. This was done following an increase to "phase 4" several days ago because the virus was already widespread in differnet locations, with confirmations in Mexico, the United States, Spain and Scotland.

While the Centers for Disease Control and Prevention (CDC) has determined that the swine flu is contagious and is spreading from human to human [2], the WHO has indicated that most people infected with swine flu make a full recovery without the need for medical attention or antiviral drugs [3].