MONTREAL -- Some of the just under 175,000 Quebecers who tested positive for the novel coronavirus are questioning whether they will need to get a vaccine.

New research out of Montreal and Toronto about COVID-19 immunity is helping paint a clearer picture on how the body responds to the virus, and experts are advising those who've recovered from the disease to get the vaccine even though it may not be necessary. 

"We don't know how long this immunity is lasting, we don't know if it's going to be identical to vaccine-induced immunity, and maybe as we get more information, if the COVID induced immunity falls off, then some of those people will have to be vaccinated," said University of Toronto immunologist Dr. Tania Watts.

As vaccinations ramp up across Canada, the research suggests the immune systems after COVID-19 have a tougher time fighting off another infection than they do with the flu virus.

Researchers found that antibodies dropped off rapidly after symptoms subsided and despite fewer antibodies, people still had some protection.

"We were able to find memory B cells even after seven to eight months post symptom onset, which is saying that the immune system is doing what it's supposed to, it's keeping a memory of it - how long they are going to remain, we don't know," said Dr. Andres Finzi of the Universite de Montreal.

Jodi Karper Fellner caught COVID-19 nine months ago and said she still has symptoms.

"There's always a feeling of pressure in my chest and in my back; and always a feeling that somebody is just ever so slightly holding on to my neck, where it's hard to take a deep breath or to exhale," she said.

The research also shows the novel coronavirus causes more inflammation than influenza does, which could explain why COVID-19 patients have a tough time fighting off a host of problems.

Fellner's blood showed no signs of inflammation, but she's been diagnosed with heart inflammation.

She says having lingering symptoms is frustrating and the experience has been a roller coaster.

"For me, it comes out of nowhere, there's no rhyme or reason that it happens, and the doctors don't know either," she said.