We can't let Canada beat us. We need to step up our disease spreading game. I propose we look into the feasibility of developing reverse vaccines to overfit the immune system to specific measles variants that it's unlikely to encounter, thus reducing immunity to real infections in people who are already vaccinated.

Alternatively, we could ban the sale or posession of contraceptive devices, because condoms are murder. And then watch the HIV infection rate spike, weakening immune responses and paving the way for measles to flourish.