Studies are showing that the first dose of Pfizer-BioNTech vaccine is highly effective, helping boost B-C's confidence to delay the second dose of all approved COVID-19 vaccines to four months. Canada's National Advisory Committee on Immunization also says Pfizer, Moderna, and AstraZeneca - can now be considerably extended, while still being effective. U-B-C adjunct infectious diseases professor Dr. Horacio Bach provides his thoughts and predicts what COVID vaccine programs may look like in the future.