As Dr. Quach said earlier, research is under way now to look at the impact of interchangeability of vaccines and at the durability of the effect of immunization. They are becoming available very quickly. As you said, NACI will be looking at more data from the U.K. next week, and so we and the world are gathering and assessing information on dose schedule on a real-time basis so we can be equipped to make those kinds of recommendations.
NACI has the breadth of expertise, which is why we rely on them as external experts to look at those data and give us their advice on dose interval, on the efficacy of one dose versus two and on the durability issues that continue to be really important from a scientific perspective.