OTTAWA -- Three-quarters of Ottawa adults have received at least one dose of COVID-19 vaccine, but the city's top doctor says vaccine coverage is not enough to stop the spread of the virus.

Mayor Jim Watson tweeted Thursday morning that 75 per cent of Ottawa adults 18 and older have received at least one dose of COVID-19 vaccine.  As of Wednesday, 63 per cent of Ottawa residents 12 and over had received at least one dose.

Ottawa hitting the 75 per cent vaccination mark comes less than a week after Ottawa entered Step One of the COVID-19 reopening plan, allowing patios and non-essential businesses to open.

In an interview on CTV News at Six with Graham Richardson Wednesday evening, medical officer of health Dr. Vera Etches acknowledged the COVID-19 signal is rising in the wastewater, which would be expected as things open up.

"What we're more concerned about is if that translates into a sustained rise, rapid uptick that's been associated with hospitalizations," said Dr. Etches.

"What's protecting us against that is largely the vaccines, but it's not enough. So the vaccination rate for our whole population is about 63 per cent, that is good. That means all those vaccinated people are less likely to get severely illness, less likely to be hospitalized even when COVID is spreading."

As Ontario accelerates the timeline for residents to receive their second dose, Dr. Etches said it's important for everyone to get fully vaccinated. The city of Ottawa has said 200,000 appointments were booked at COVID-19 vaccination sites between June 1 and July 6.

"We need the two doses really to be able to maximally protect the population. We also need this coverage to be even, we don't want pockets of the community that aren't protected as much and so that's where COVID flares up," said Etches.

In a separate interview on Newstalk 580 CFRA's Ottawa Now with Kristy Cameron, Etches said while the vaccines are protecting people from getting serious illness and transmitting the virus to other people, it's "probably not enough yet" to let our guard down.

"I just want to encourage people that caution is still needed, we still need folks to think about, can you keep the number of close contacts you have limited," said Etches.

"So it's growing, when you think back over the last week – can you think about how many close contacts and try to keep that lower as we still need a bit more."