Preparing for the Worst

UTMB’s Alan Barrett is quoted in this article about the swine flu. “(Barrett says) travel by carriers of influenza, be they people in aeroplanes or birds on the wing, means regional mutations quickly spread around the world. Hence, even when flu subsides at the end of the northern hemisphere’s winter, the disease merely shifts to the southern hemisphere (which is now entering its winter). Six months later, it moves back. When the mutations are gradual, as with seasonal flu, it is known as drift; when they are abrupt, as with the new strain of H1N1, you have a shift on your hands.”