Vaccines have been targeted in this way in most places. It's not surprising, especially when it's happening in countries that started to vaccinate older people first. And so is it a problem that you might have spiking cases and amongst young people? I think you're exactly right. Absolute numbers are largely going down. But of those people who are getting infected, a larger proportion of them are younger. The distribution s trending downwards. Now what that means for the pandemic and how big of a problem it is - hard to pinpoint.