WINNIPEG -- The province’s vaccine task force said there is no excuse for the long waits people experienced at the RBC Convention Centre Supersite in Winnipeg over the weekend.

Manitoba's Vaccine Implementation Task Force Co-lead Johanu Botha said on Wednesday that the one to two-hour delay was related to staffing and the switch over to a new model being tried out – having people stay in place and immunizers circulate to administer the shots.

Botha said this model allowed for 4,000 appointments to happen each day, but said the system is very susceptible to delays.

One issue can quickly turn into a bottleneck he said, adding the lesson is for the processes to be followed closely.

He said there were one to two-hour delays for appointments, though he said everyone with an appointment was immunized.

Botha said the mandate is for supersites to vaccinate everyone who shows up for their appointment.

On Monday, the province announced it is halting AstraZeneca vaccinations for people under the age of 55 due to side effects seen in cases in Europe, which include rare, but dangerous blood clots.

Reimer said the benefits of the vaccine outweigh the risks for those older than 55. She noted these blood clots affect about one in 100,000 to one in a million people, noting the symptoms mirror those of a heart attack or stroke.

On Wednesday, Botha said the Moderna shipments for April 5 are expected to be more than a week late, which may cause pop-up clinics to be delayed.

The province said it plans to administer 45,960 doses by April 6.

- With files from CTV’s Simon Stones and Kayla Rosen