MONTREAL -- Since the start of the COVID-19 pandemic, there have been theories that the virus could manifest itself in the form of a loss of taste or smell among people who have tested positive.

On Wednesday, Quebec researchers proved the theory to be true. In a study published in the Canadian Medical Association Journal, they reported that nearly two-thirds of the COVID-19 patients they analyzed experienced a full or partial loss of taste and smell, and what’s more is that among them, these symptoms tended to show up independently of those more commonly associated to the virus. 

“In a lot of patients, we saw that loss of smell is not necessarily seen with other symptoms like fever or shortness of breath or coughs,” said Dr. Alex Carignan, a medical microbiologist and infectious diseases consultant in Sherbrooke who directed the study. “A lot of people present mainly with loss of smell and sometimes other symptoms like fatigue or headaches.”

The study – which was a collaboration between the University of Sherbrooke and one of the province's integrated health and social service centres (Eastern Townships) – suggests for people who have these symptoms to be tested for the virus and tested again if their first results come back negative.

“These symptoms are really distinctive features of (COVID-19), and should certainly serve as an indication for testing,” Carignan said.

Two groups of 134 people each were analyzed through the study: one consisting of COVID-19 patients, and one of people who were sick with the flu. About 65 per cent of people from the group of COVID-19 patients reported a loss of taste and smell, compared to 8 per cent from the other.

“It was already known that with a common cold you can also have similar symptoms,” Carignan said, explaining the necessity of having a control group in the study. “But we wanted to see if it was more than what we usually see with common colds.”

The patients from the control group were mainly people who had been sick but tested negative for COVID-19 around the same time as the group who tested positive, Carignan said. 

Next up on the researchers’ to-do list is to retroactively test samples from patients who were tested for the flu in January and February – before the first reported COVID-19 case hit Sherbrooke – to see if the novel coronavirus was circulating before public health officials made the announcement. 

“We keep (samples) for a few months, so we have these samples in our lab, and I hope that other labs in Quebec still have their samples for influenza,” Carignan said. “It would be nice to try to find earlier cases than the official ones.”