The COVID-19 Pandemic & More: Time to assess lessons learned, and to implement science-based measures to reduce airborne transmission

Colorado’s COVID-19 epidemic may be starting to turn the corner. Hospitalizations fell by 400 to 399 last week, down from 440 the previous week. The number of cases is trending downward, and test positivity has peaked. Vaccination levels raise concerns about population immunity, especially if the next variant is more infectious than previous variants (probable possibility) and more virulent (uncertain possibility). To date, 70.9% of Coloradans have completed the primary series, while only 22.4% of those eligible have received the bivalent booster.

“Tripledemic” is still gaining attention. fortunately, Respiratory syncytial virus (RSV) is on the decline in Colorado parallel with National trends. Influenza is still widely spread, but Surveillance data indicate a potential plateau. With the state’s influenza vaccination rate at 54.7%, Colorado would still benefit if unvaccinated people get a flu shot. Hopefully, Colorado has avoided a triplademic that would have strained healthcare capacity.

We are nearing the three-year mark for the pandemic and face an uncertain future that will depend on the changing whims of SARS-CoV-2. As the long pandemic ordeal may be coming to a local end, now is an opportune time for a thorough assessment of lessons learned. Last week, Bill Berman, former director of Denver Public Health, and I published one Editorial in Colorado Sun calls for such evaluation. We stated clearly, concluding: “It is time for a coordinated and coordinated review of the Colorado COVID-19 response, bringing key players to the same table.” In calling for such a review, we note that there are many organizations involved in responding to COVID-19 and that all of them need to be engaged in addressing and evaluating the underlying “systems.” We focus on addressing topics such as: data and monitoring; health disparities; impact on K-12 education; contact support and contact tracing; congregate living arrangements, particularly skilled nursing facilities; and coordination of system-wide COVID-19 responses. Our call for a comprehensive review is not a criticism, but a reminder that “an integrated and coordinated review” helps increase preparedness. Epidemics including Kovid-19 are not going away.

One lesson learned and relearned is the need to reduce airborne transmission of infectious agents to indoor spaces. As we spend most of our day indoors, mainly in mechanically ventilated environments, interventions to reduce transmission can significantly reduce the risk of infection. Pioneering work on controlling airborne transmission was carried out by Wells and Riley In the early 1930s. Then, science progressed a bit until the Covid-19 pandemic. Now, we have a key package of measures that will reduce airborne transmission: increasing ventilation to dilute the concentration of pathogens; filtration to remove pathogens; and ultraviolet C irradiation to kill pathogens.

Last week, key publications were released that address these measures and the steps to implement them. This The Lancet Covid-19 Commission has published recommendations for ventilation rates to reduce airborne infection. Commission members review the literature, including the work of relevant organizations, and use expert judgment to propose three tiers of ventilation deemed to provide “good,” “excellent,” or “superior” control. This American Society for Heating, Ventilating and Air Conditioning Engineers (ASHRAE) Develops standards for ventilation that are widely applied and form the basis for building codes. Last week, ASHRAE committed to developing a pathogen mitigation standard that could be enforced.. In the 1990s, I served on ASHRAE’s committee on its Ventilation Standard 62: Ventilation for Acceptable Indoor Air Quality when there was controversy over whether acceptable indoor air quality could be achieved if there was smoke. After a bitter struggle with the tobacco industry and its surrogates, the answer was no. A pathogen mitigation standard needs to be developed but producing one will be challenging. Good luck to this committee of volunteers. last, The White House released a fact sheet announcing its commitment to clean indoor air across the country.

We continue to rediscover the importance of indoor air to public health. Not surprisingly, as people in high-income countries spend most of their time indoors, indoor air pollution by chemicals and pathogens can have powerful health effects, causing disease and harming public health. With my Harvard colleague, John Spangler, I edited one of the earliest books on the subject, Indoor Air Pollution: A Health Perspective. With John McCarthy, we edited a 1,500-page book, Indoor Air Quality Handbook. A trio of Intrepid editors put together the recently published 2,200-page update. My point here, aside from marketing my old books, is that knowledge of indoor air pollution is enormous. Implementation of what we know is lacking. I wait to see if the pandemic will spur action or just reports.

We continue to prove that vaccination is important, whether it’s eradicating smallpox or controlling COVID-19. In a retrograde move, suitable for covid follies acceptance, the A recently passed defense funding bill also repeals mandatory vaccination against SARS-CoV-2 for the military. Republican demands for a reversal of vaccination policy and claims that the vaccine requirement is hurting recruitment have been accepted. Many vaccinations are mandatory for military members and are critical to ensuring the health and readiness of the armed forces. Those pushing for repeal of the order should read of John Berry The Great Influenza, which documents the toll of the 1918 epidemic on young recruits and its effect on soldiers traveling by ship to Europe. Politics should not reach the vaccination of the military. The lethal influence of political considerations on epidemic control is a lesson learned time and again since March 2020.

Jonathan Samat, MD, MS
Dean, Colorado School of Public Health