was a trade-off to get as many people fully vaccinated as quickly as possible, even if a booster dose later would almost certainly be necessary.

And, unfortunately, we're STILL in that mode because there's been so much shitheaded-ness about getting vaccinated, not to mention masking and social distancing, even though they long ago determined the optimal spacing between doses to produce maximum antibody levels is 8 weeks. On the other hand, antibody levels are not sustained for long after the first dose, making a longer spancing between doses a gamble that we still can't afford to take.

From "Public health statement on extension of the interval between first and second doses of COVID-19 vaccines in BC" at:

http://www.bccdc.ca/Health-Info-Site/Documents/COVID-19_vaccine/Public_health_statement_deferred_second_dose.pdf

Summary:

There is good scientific evidence from clinical trials and real-world experience of a high degree of protection following a single dose of COVID-19 vaccine. Providing a first dose to as many people as possible saves more lives and avoids more cases and hospitalizations and supports a return to essential functions in our communities. This aligns with recommendations from the Canadian National Advisory Committee on Immunization. Completion of the 2 dose COVID-19 vaccination series remains important to provide long-term protection.

Situation:

- Initially, the pace of our COVID-19 vaccine supply was insufficient to vaccinate everyone right away and we had limited supply of COVID-19 vaccine.

- Prior to the vaccination campaign, there was minimal population immunity, leaving the vast majority of the BC population susceptible to COVID-19.

- While older adults and people with certain medical conditions are at increased risk of serious health outcomes and death due to COVID-19, adverse events have been observed in all age groups.

What we know about vaccines in general:

- It generally takes at least 2 weeks to mount an immune response to a vaccine dose.

- For most vaccines, the first dose contributes the most towards short-term protection. Additional doses extend protection over the long-term and are often given months or even years apart.

- For most vaccines, antibody levels decline gradually over time. They do not suddenly fall below protective levels. Even months or years later, another vaccine dose can boost antibodies to higher levels.

- For many vaccines, a longer interval to the second dose results in higher antibody levels after the series has been completed. Higher antibody levels are generally associated with longer duration of protection.

- Generally, vaccine manufacturing companies and national vaccine advisory bodies specify a minimum interval between vaccine doses but do not specify maximum intervals. Delay in receipt of a scheduled dose does not require restarting a series.