One dose not sufficient
The all-important push to vaccinate Americans against COVID-19 faces a true dilemma: Two doses are required for the vaccines available right now. But because Americans — like people in many countries — would not refrain from holiday gatherings and keep their masks on, cases are surging higher than they’ve ever been. A single dose of vaccine would provide significant protection, but it’s not enough for long-term immunity.
If states can’t collect and distribute the second doses to their residents in time, we don’t know what that might mean for the vaccines’ effectiveness. None of the clinical trials included an extended time between doses; in other words, no one knows whether people would be as protected if they had to wait extra weeks for the second dose. Though more spreadout shots work for other viruses, these two vaccines use an entirely novel mechanism. Would the protection last long enough for the second dose and would the two together work as well? Quite possibly. Or not.
There are other concerns if the second doses don’t come through fast. One is that people will be less likely to show up for the follow-up if there’s a longer time period between shots.
Another possibility: People’s trust in the vaccine may erode. Many Americans are still reeling from revised and sometimes contradictory messages that came from federal authorities about masks and other pandemic-related issues; now the message on vaccination is changing as well.
Failure to get a second dose, or to get it within a reasonable time, raises another concern among health experts: If the vaccine is effective enough to keep a person from having symptoms but not effective enough to completely fight off the novel coronavirus, partly vaccinated people could act as the incubators for a mutated, vaccine-resistant virus.
Regardless, the current surge left health authorities without much choice. Using all those doses to give one shot to as many Americans as possible represents a real opportunity to save lives now and bring down COVID-19 infection rates for the population as a whole, versus theoretically causing problems down the line.
Getting the vaccines rolling out will require a faster, more effective procedure to distribute the shots than California and most other states have managed so far.