Contact tracing is no longer an effective tool in the province's fight against surging cases of the Omicron coronavirus variant, says B.C.'s top health officer.
The province has adapted its strategy to prevent transmission of the highly-infectious COVID-19 strain, Provincial health officer Dr. Bonnie Henry told reporters in a press briefing Friday (Jan. 21) morning.
And while contact tracing has been an effective mechanism for public health intervention in the past, Henry noted that is an increasingly difficult process due to the infectious variant.
"Disease characteristics that make contact tracing effective are things like having a longer incubation period because you have to have time to find people after somebody has been tested," she explained, highlighting that the Omicron variant has a signifcantly shorter incubation period.
As COVID-19 strains "become more and more infectious," it is more challenging to find people through contact tracing, added Henry.
A disease such as measles, on the other hand, has a two- to three-week incubation period. The health officer said contact tracing for diseases with longer incubation periods like this allows time to identify and reach a high proportion of contacts and take measures to prevent the spread of the virus.
Earlier in the pandemic, individuals infected with the Delta variant typically had a five- to seven-day incubation period, Henry noted. This period allowed public health teams to locate the individuals and prevent them from spreading the virus to others before they developed symptoms.
Individuals infected with Omicron may also "have mild or asymptomatic infections and not even realize that they are affected," she emphasized. Further, at this juncture in the pandemic, the majority of B.C. residents are vaccinated. Some adults with mild to moderate COVID-19 who are at high risk of progressing to serious disease will have access to Canada's first oral antiviral COVID-19 treatment.
"So with the emergence of these more transmissible variants are shorter incubation periods, COVID-19 is no longer an infection for which contact tracing is an effective intervention," Henry underscored.
"We now need to shift our management and think about the things that we can do across the board to prevent transmission and to prevent ourselves from being exposed."
While vaccination is the most effective way to prevent transmission from COVID-19, individuals should also manage their symptoms and stay home if they feel ill.