Based on these articles the past couple months, the Moderna vaccine seems slightly but consistently safer than the Pfizer vaccine. Adjusted for market share though, which is actually the safest? This subject is so politicized, the important facts are hard to discern.
You would want to go back to the beginning to really assess that, since the start had people with known severe allergies taking both and experiencing anaphylaxis. Now, all of them made full recoveries and that’s usually treated with a shot of epinephrine, but it’s still a scary thing. Since the new guidance calls out excluding those with a known history of severe allergies to medicines, those already rare events (about 1 in 400,000 for Moderna and 1 in 1,000,000 for Pfizer as I recall from memory) became exceedingly rare.
Still, even in the early days, that 1 in 400,000 comes to 0.00025%. Looked at another way, the average person meets roughly 80,000 people over the course of their entire lives. If every single person you have ever met - or will ever meet - all got Moderna, there’s only a 1 in 5 chance ANY of them would experience a severe side effect. The myocarditis described here is extremely common. People get it when they catch a cold or have the flu. Plenty of other things can cause it too. Most of those cases show no symptoms at all or are so mild you’d barely notice anything. And nearly all resolve on their own. Most cases happen in children anyway.
Of the 285 confirmed cases of myocarditis after vaccination, 270 have already fully resolved with complete recovery. The other 15 are in progress. The data available today says that unless you have a history of severe allergic reactions, both Pfizer and Modera are very safe. J&J is also safe with the caveat that it’s ever so slightly less safe if you’re a woman who has periods (i.e. you’re between roughly 12 and 50). But whereas those clots appear in roughly 1 in 400,000 women, certain hormonal birth control pills have been shown to product clots in about 1 in 1,000 women. My pro-life beliefs obligate me to prefer the Pfizer and Moderna vaccines, since they didn’t use fetal stem cells in any part of their production creation or testing (independent third party confirmatory testing required by the FDA did, but the products had already been produced, bottled, frozen, and ready for shipment by then). J&J used fetal stem cells at every step of the process to develop and test their vaccine. But as for safety? They’re all quite safe.