"It is everywhere. So you do not need to have a party to get the swine flu.

VOA: standard.2009.12.18

What happens is suppose you have the flu and you get very nauseous and then at the same point you eat some sashimi for the first time.

假设你得了流感，感觉非常恶心,与此同时，你又第一次吃了生鱼片。

耶鲁公开课 - 心理学导论课程节选

The first step uses a bit of influenza DNA to get the patient's immune system to begin fighting off the flu, and then the protection is given a "boost" some time later by the second step, which can be either another bit of DNA or a conventional flu vaccine.

VOA: standard.2010.07.21