Nearly 1,000 confirmed cases of a new sub-lineage of the "Omicron" variant have been detected in Ontario so far, according to newly released data from "Public Health Ontario," but experts say it does not warrant major concern.

In a recent briefing, Public Health Ontario said that BA.2.20 - an evolved form of the Omicron BA.2 subvariant - is primarily growing in Ontario.

The memo states that the date of the first BA.2.20 sample collection is February 14 and that 996 cases have been confirmed in the province.

Over the past four weeks, the percentage of BA.2.20 cases has remained stable, at about 5.5 percent, but Public Health Ontario indicated that testing eligibility is currently limited to high-risk populations and that the percentage does not represent all BA.2 cases.

Dr. Zain Chagla, an assistant professor of infectious diseases at McMaster University in Hamilton, said there is "no need to panic" because BA.2.20 has not caused "major jumps" in coronavirus infections.

He said in a Friday interview, "But acknowledging that vaccines still appear very effective, levels are declining... and wastewater data is low, and ICU remains low as well, really indicates that community transmission of this (sub-lineage) does not necessarily change the game completely; it will not lead to some kind of epidemiological shift in terms of increased transmission."

Public Health Ontario says BA.2.20 differs from BA.2 lineages by two additional specific mutations, but the impact of these mutations on transmission, risk of severe disease, reinfection, and breakthrough infections is unknown.

Dr. Gerald Evans, professor of infectious diseases at Queen’s University and medical director of infection prevention and control at Kingston Health Sciences Centre, said, "BA.2 was sufficiently different from BA.1; when it came in, it displaced BA.1, but BA.2.20 does not do the same with BA.2."

"So my view is that this is a phenomenon we are watching and do not see as uncommon; it has been seen worldwide and usually these (sub-lineages) come, cause few cases, do not really have a competitive advantage and eventually either die out or co-circulate somewhat alongside the original variant they emerged with."

The public health unit with the highest proportion of BA.2.20 cases was Toronto Public Health at 18.8 percent of cases, followed by Middlesex London Health Unit at 12.7 percent.

Dr. Theresa Tam, Chief Public Health Officer of Canada, said Friday that public health officials are tracking different COVID-19 sub-lineages but are mostly monitoring a new variant that could cause a significant increase in transmission.

Ontario reported 1,412 new COVID-19 infections on Friday despite PCR testing being limited to certain groups.