EDMONTON -- The mass vaccination clinic at Edmonton's EXPO Centre administered a fraction of the thousands of COVID-19 shots it is capable of on Wednesday.

According to Alberta Health Services, nearly 250 people had booked appointments as of 10:15 a.m. at the super centre.

But when Joanne Scott arrived to get her vaccine around noon, there were no lineups. At one point, there was only one other person in queue.

AHS spokesperson Kerry Williamson told CTV News Edmonton officials "expected uptake to be slow so we're not currently running the site at full capacity."

When the site opened Monday, officials expected about 1,500 shots would be administered.

On Tuesday, workers immunized another 520 people.

"We acknowledge that some people may have concerns about the AstraZeneca vaccine, however it is a safe and effective way of protecting yourself and your loved ones from COVID-19," Williamson said.

"AHS and Alberta Health will continue to engage with Albertans, to reassure them that AstraZeneca is a safe option. If people have concerns about the AstraZeneca vaccine, we encourage them to talk to their physician or a pharmacist."

AHS will ramp up the site's capacity as Alberta receives vaccine supply.

AstraZeneca bookings are available at the EXPO Centre to Edmontonians aged 55 to 64 online or at 811.