the pfizer vaccine also appears to work against the worrisome south african variant. but johnson & johnson is facing fresh scrutiny after an ingredient mixup at a baltimore manufacturing plant, potentially ruined about 15 million future doses. it s really quite unfortunate that about 15 million doses now are not going to be able to be used. but you do have checks and balances and you see that. and that s the reason why the good news is that it did get picked up. reporter: the mistake at bioemergent caught weeks ago during a quality control check. the fda saying there was no risk to anyone already vaccinated and none of the ingredients in question made their way into final doses. johnson & johnson insists it s still on track to deliver 100 million doses by the end of may. today, thousands of excited fans filling into stands for baseball s opening day. each stadium with its own safety protocol. at yankee stadium, temperature checks and proof of vaccination or a negative test required