Dr. Bonnie Henry refers to airborne transmission of COVID-19 in Jas Johal interview

B.C.'s provincial health officer did not elaborate on what she meant in using that term

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      On August 8 when I highlighted Dr. Bonnie Henry's comments on monkeypox, I did not mention that she had also stated in the same CKNW interview that COVID-19 is spread through the air.

      While this may not seem remarkable to many readers, it opens the possibility of B.C. public-health officials acknowledging the importance of tiny aerosols in transmission of the disease.

      Who knows? Perhaps the next shoe to drop will be more public education about the impact of COVID-19 on the brain and cardiovascular system.

      It's worth noting that neither Henry nor Health Minister Adrian Dix uttered the words "COVID is airborne" last January on the second anniversary of the first diagnosis of the disease in B.C.

      Since then, however, Dix and Premier John Horgan have acknowledged that the disease is transmitted through the air, though they have not been pressed in detail on how this occurs.

      Two years ago, several B.C. physicians—including some who work as clinical professors of medicine or at health authorities—actually  signed a public letter maintaining that the dominant form of transmission of COVID-19 is through droplets and close contact. Other signatories were infectious-disease experts in Ontario who often appear on national newscasts as COVID-19 experts.

      The B.C. signatories to this letter in Clinical Infectious Diseases in August 2020 were Dr. Srinavas Murthy, Dr. Jennifer Grant, Dr. David Patrick, Dr. Jim Hutchinson, Dr. Pamela Kibsey, Dr. Jocelyn Srigley, Dr. Laura J. Sauvé, Dr. John Galbraith, Dr. Troy Grennan, Dr. Edith Blondel-Hill, and Dr. Ghada Al-Rawahi. Grant is one of the leaders of the "Urgency of Normal" movement, which has called for the retirement of vaccine mandates in schools.

      Unfortunately, the CKNW interviewer, Jas Johal, did not press Henry on what she meant when she acknowledged on his show that COVID-19 is airborne.

      For anyone who interviews Henry or Dix in the future, here are a few questions that need to be asked.

      1. Do you believe that the SARS-CoV-2 virus can be transmitted on aerosols smaller than five microns?

      2. How long can aerosols smaller than five microns remain in poorly ventilated indoor air?

      3. Do you believe that airborne aerosols, rather than droplets larger than 100 microns in diameter, are the primary form of transmission of the SARS-CoV-2 virus indoors?

      4. What measures are necessary to reduce the number of aerosols of five microns or smaller from entering people's lungs in classrooms and on ferries and transit?

      5. Should we be measuring carbon dioxide levels in crowded indoor spaces as a proxy for measuring the concentration of virus?

      According to University of Colorado Boulder atmospheric chemist Jose Luis-Jimenez, aerosols are smaller than 100 microns in diameter. Most are smalller than five microns and they can all deliver respiratory viruses.

      These microscopic liquid, solid, or semisolid particles are produced when breathing, talking, shouting, coughing, and sneezing, according to a paper he coauthored in Science last year.

      The paper noted that when inhaled, these smaller aerosols are deposited in the bronchiolar and alveolar regions of the lungs.

      The smaller aerosols carrying the virus can remain suspended in indoor air for hours, according to published research in the New England Journal of Medicine.

      paper in Emerging Infectious Diseases last year noted that there has been long-range transmission of the virus between people in adjacent pandemic hotel rooms even though they were never in one another's presence.

      Virus-laden droplets are larger than 100 microns and are mostly produced when people sneeze or cough.

      According to the paper in Science, these larger droplets remain suspended in the air for less than five seconds. Therefore, they are a poor deliverer of respiratory viruses, only doing this within a short range.

      In May of 2021, three researchers—Oxford University's Dr. Trisha Greenhalgh, UVic nursing professor Damien Contandriopoulos, and Brunel Business School professor Mustafa Ozbilgin—wrote a paper explaining the failure of public bodies to acknowledge and act in a timely manner on the evidence base for airborne transmission of COVID-19.

      One of their three case studies was British Columbia.

      "Aerosol scientists—typically, chemists, and engineers—representing the heterodoxy were systematically excluded from key decision-making networks and committees," the researchers stated. "Dominant discourses defined these scientists’ ideas and methodologies as weak, their empirical findings as untrustworthy or insignificant, and their contributions to debate as unhelpful."

      As recently as last February, Vancouver Coastal Health's chief medical health officer, Dr. Patricia Daly, claimed that there's great debate over whether COVID-19 is airborne.

      Around the same time, one of the signatories to the 2020 letter, Srigley, and one of her colleagues, Dr. Alison Lopez of B.C. Children's Hospital, wrote a letter to the Lancet questioning whether the dominant form of transmission of the virus was airborne.

      That came after Jimenez and other researchers had published a paper in Environmental Science & Technology examining key factors influencing airborne transmission of COVID-19 indoors and comparing its spread to measles and tuberculosis.

      "Measles outbreaks occur at much lower risk parameter values than COVID-19, while tuberculosis outbreaks are observed at higher risk parameter values," the researchers wrote. "Because both diseases are accepted as airborne, the fact that COVID-19 is less contagious than measles does not rule out airborne transmission."

      Now that Henry has publicly acknowledged that COVID-19 is transmitted through the air, will health authorities invite greater input from chemists and engineers in efforts to reduce the spread?

      And if so, what form will this take?

      Or is simply saying that a disease is airborne mean that there will be zero change in how the province responds?

      Talk-show hosts like Johal might want to raise these issues with Henry, Dix, and the future premier of the province, David Eby, the next time they appear on their programs.

      These broadcasters should also consider pressing B.C. Liberal Leader Kevin Falcon, given that he's been a COVID-19 enabler by letting the government off the hook.

      With nearly 4,000 COVID-linked deaths in B.C. by official statistics and thousands more "excess-mortality" deaths since the pandemic began, it's time start demanding accountability with more targeted and scientifically informed questions for our leaders.

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