The novel mu strain of the SARS-CoV2 coronavirus, also referred to as B.1.621, has taken a hold of at least 50 countries, with features that make the virus particularly concerning. Three months ago, the World Health Organization first identified this strain as a “variant of interest”. The strain reportedly originating from Columbia, is now responsible for one-third of the COVID-19 cases in that country.
While early studies posited the variant was not as transmissible, novel results appear to contradict preliminary findings. For instance, while COVID’s infective properties have often been associated with the spike protein, novel understandings of the virus’ mutations beyond the spike are now being considered. It is of utmost importance that researchers continue to explore the precise nature of these mutations as researchers suggest that it may be more complex than initially thought.
As of October 31st, 78 per cent of Canadians have received at least one dose of the COVID-19 vaccine. In spite of this however, how protective the vaccines are against the mu variant is a matter scientists are still uncertain about. In contrast to variants of concern such as alpha, beta, gamma, and delta, mu has been labeled under variants being monitored owing largely to this immense uncertainty.
This strain continues to be one of concern not particularly due to its infectivity but rather because of its virulence. It has a large number of escape variants, which are mutations of the virus that can evade the surveillance of the body’s immune system. Robert Shafer, MD, a professor of medicine in the Division of Infectious Diseases at Stanford University in California, claims that the “[Mu variant] might pose a threat to populations with increasing numbers of persons who have become vaccinated and/or previously infected.” In fact, according to the United Nations, this variant is not only thought to be rising in number, it has also been suggested to be more resistant to vaccines.
One New England Journal of Medicine study conducted by researchers at the University of Tokyo showed that this variant shows stronger resistance to COVID-19 antibodies in comparison to its delta counterparts. This is due to the COVID-19 “spike protein” in the mu variant having a variety of mutations, which contributes to its astute and enhanced ability to escape interactions with the vaccine antibodies.
As the reality of this uncertain variant dawns, we must come to terms with a new culture of established preventative disease transmission measures – social distancing, masking in public, and hand hygiene. As these strategies have a significant and strong evidence base in reducing the spread of this global threat from individuals with COVID-19, it becomes all the more urgent for us to create new norms in how we construct and participate in society.
Peter Anto Johnson, MSc is a research program officer at the Antarctic Institute of Canada and MD student at the University of Alberta. He was recently named Top 40 Under 40.
John Christy Johnson is a research program officer at the Antarctic Institute of Canada and an MD/MSc biomedical engineering candidate at the University of Alberta
Austin A. Mardon, CM, PhD, FRSC is an adjunct professor in the Faculty of Medicine and Dentistry at the University of Alberta, director of the Antarctic Institute of Canada, an Order of Canada member, and Fellow of the Royal Society of Canada.