Australia was slow off the mark kicking starting its vaccination program.
Its since been widely successful with circa 90% double-vaccinated (there are small state to state variances).
The current time frame for a booster shot in Australia is 6 months after the second dose. Health Minister Greg Hunt has asked the government's immunisation panel, the Australian Technical Advisory Group on Immunisation's (ATAGI), to review this time frame for COVID-19 booster shots.