Lotta buzz online about this but it’s a story that “feels” newsy more than it is newsy. Instinctively we all formulate the vaccine process this way: “First dose + second dose = no more worries.” And that’s basically true, but not quite true.
I received the second dose of the #COVID19vaccine last week and understand the affects take time. I have continued to be tested regularly, wear my mask and follow the recommended guidelines.
— Adriano Espaillat (@RepEspaillat) January 14, 2021
A vaccine that’s 95 percent effective isn’t 100 percent effective, by definition. And the fact that a vaccine is 95 percent doesn’t necessarily mean that only one in every 20 people who get their shots and then encounter the virus in the wild should test positive. It’s not calculated that way. It’s based on relative risk: Pfizer gave half of its trial group the vaccine and half a placebo and then compared the percentage in each group that got infected. That’s where the 95 percent figure comes from.