So how scared should we be?
As far as this epidemic is concerned, it’s too early to tell. One unknown is how widespread the virus is in Mexico. If it is ubiquitous, and had not been noticed earlier because it emerged during the normal flu season, then this epidemic may turn out to be insignificant, at least to start with. No flu death is welcome, but in this case the new disease might not increase the immediate burden greatly. But if the new strain is relatively rare, or what is being seen now is a more dangerous mutation of what had once been a mild virus, then the proportion of infected people dying may already be high. The death-toll, then, will rise sharply as the disease spreads.
Either way, the authorities were right to hit red alert. Influenza pandemics seem to strike every few decades and to kill by the million””at least 1m in 1968; perhaps 100m in the “Spanish” flu of 1918-19. And even those that start mild can turn dangerous. That is because new viral diseases generally happen when a virus mutates in a way that allows it to jump species, and then continues to evolve to exploit its new host. If that evolution makes the virus more virulent, so much the worse for the host. HIV, the AIDS-causing virus, lived happily and benignly in chimpanzees before it became a scourge of people. In Mexico, the early indications are that two pig viruses that can infect people but rarely pass from person to person recombined with each other to create a virus which does so easily.
A CNN article interviewed Ron Paul who was a freshman congressman when there was another “pandemic” threat in the 70’s. Congress voted to vaccinate the entire country. 25 people died from the shots, 1 died of the disease. Ron Paul voted against the measure.