With omicron, it's just not really clear what level of immune escape there might be. The studies that can help answer that question are being launched right now and will take a few weeks to come through. And we also have to see what omacron does, like continuing in south africa, to see if it really does to be out competing dealt with there. If it's able to establish tow holds and spread in other countries over dealts a, that would show that it really is more transmissible.