GoofGoof
Premium Member
The 3 or 4 weeks seems to be more like a “you have to wait at least this long”. A minimum wait as opposed to a maximum. Remember when they ran the trials the goal was to end the pandemic quickly so if they picked 6 months for the booster the US would be waiting until the end of Summer for a lot of people to get their second dose. The companies knew the desire was to determine how quickly you could complete the series and still have the vaccine be effective. The desire was to accelerate not delay. The plan to delay is due to a shortage of supply.Yep, in order to get these vaccines out ASAP there simply wasn't time to trial different intervals. If there was, they'd have studied second doses at 4 weeks, 8 weeks, 16 weeks, 6 months, etc. That's why we are now getting some data to support longer intervals, which is not unexpected given how many other vaccines have delayed second doses.
Ultimately, the USA follows the existing guidelines because they have sufficient supply and this is the correct choice. Canada and the UK delaying second shots is also the right choice, based on the current conditions. It has been reported that in Canada, new COVID cases amongst those with one shot account for only 2% of cases. One dose (for now) was a calculated risk that appears to be paying off.