B.C. residents have cut human contact in half, poll reveals

The number of British Columbians' human-to-human contacts may have been cut in half compared to numbers of such interactions before the pandemic, according to preliminary data from a B.C. online survey.

Respondents to 70,000 surveys listed the number and description of people with whom they have had contact, where and for how long and whether or not they wore masks or other protection. It showed a provincewide average of four persons each per day, according to preliminary data from the B.C. Mix survey posted on the B.C. Centres for Disease Control website.

“It's important to know when people are in close contact with one another, how many contacts they've had and the duration and frequency of these contacts to figure out what is the impact of the public health layers to reduce transmission,” said principal investigator Dr. Naveed Janjua.

Participation is voluntary and respondents sign up for emails once a month, asking them to tally the number of people with whom they had an exchange of three or more words.

Referring to a specific 24-hour period, they are asked to include anyone from retail clerk, doctor, teammate, friend, co-worker or stranger, for instance, and where the encounter occurred, including someone's home, office, a store, on the street, in a park or sports field, etc.

Most of the 44,000 respondents filled out one survey and some filled out more than one, said Janjua.

“We need adequate numbers so we can access the patterns over a period of time,” he said.

“This (44,000) is a good number,” he said. “We want to see how contacts are changing over a period of time. We will need more people to participate as the vaccine rolls out, to get a good sense of what the impact of the number of contacts is on transmission rates.”

Mathematical models will be created to see if there's a connection to average number of contacts and COVID's transmission rate of transmission among the B.C. population, he said.

The data are still being analyzed and scientifically reviewed internally before being posted for public access, he said.

Researchers assume the number of contacts before the pandemic was declared on March 11, 2020, was on average eight a day in B.C., based on baseline numbers in Quebec. That province had been collecting such data before COVID, to determine if numbers of contacts had an impact on seasonal influenza transmission. B.C. started collecting data in September. For October and November, the average number of contacts was six per day, and it dropped to four a day for 2021 so far, said Janjua.