The FDA will say this week that if you want a COVID-19 vaccine booster shot, it won’t matter whether you were originally vaccinated with another brand. You will soon be able to “mix and match” the vaccine manufacturer to get your booster. The agency is also expected to recommend that people get a booster shot from the same maker as their original vaccination. And for those Americans who received their original vaccine from Johnson & Johnson, there are questions about the correct dosage. If you want to see confusion, incompetence, and uncertainty coming from a federal agency making life and...