Systematically omitting indoor air quality: sub-standard guidance for shelters, group homes and long-term care in Ontario during the COVID-19 pandemic

ABSTRACT

Public Health Ontario (PHO) is mandated by legislation to share scientific advice during infectious disease outbreaks and help reduce health inequities in Ontario, Canada. PHO was founded in part to address the failures of Ontario’s public health system during the 2003 outbreak of SARS-CoV-1, which included the failure to address airborne transmission. By January 2021, public health authorities had access to a body of literature suggesting SARS-CoV-2 was airborne, and had received urgent warnings from scientists. We set out to document how PHO responded to the likelihood – and, eventually, the certainty – of airborne transmission in the context of its guidance for congregate settings such as long-term care and shelters. In October 2021, we reviewed PHO’s public, written COVID-19 guidance for these settings, with a focus on indoor air quality (IAQ) measures that mitigate airborne transmission, such as ventilation. We identified 11 PHO documents for congregate settings. They contained no references to IAQ measures. We did, however, find references to IAQ measures in parallel documents for schools, summer camps, and clinical offices. Our findings demonstrate PHO omitted key infection prevention measures from its COVID-19 guidance for congregate settings, putting workers and residents at greater risk of exposure, illness and death, and exacerbating health inequities.

KEYWORDS:

• Public health
• COVID-19
• health equity
• congregate settings
• ventilation

Introduction

Public Health Ontario (PHO) is mandated by the Ontario Agency for Health Protection and Promotion Act to share ‘scientific and technical advice and support’, ‘undertake research related to evaluating the modes of transmission of febrile respiratory illnesses’, and help ‘reduce health inequities’ in Ontario, Canada, a jurisdiction of more than 15 million people (Government of Ontario, 2007).¹ PHO was founded in part to address the failures of Ontario’s public health system during the 2003 SARS outbreak, which included the failure to apply the precautionary principle in the face of potential airborne transmission (Campbell, 2006; Goel, 2012).

In this paper, we set out to document how PHO responded to the possibility – and, eventually, the certainty – of airborne transmission during the COVID-19 pandemic in the context of its guidance for long-term care and congregate settings such as shelters. In October 2021, we reviewed PHO’s public, written COVID-19 guidance for these settings, with a focus on indoor air quality measures such as ventilation, which have the capacity to mitigate airborne transmission.

Background

COVID-19 and airborne transmission

In March 2020, the World Health Organization declared the COVID-19 outbreak a pandemic. Soon after, scientists, engineers, and physicians began urging public health authorities to address airborne transmission (Aladodo et al., 2021; Glowacki, 2020, 2021; Jimenez et al., 2022; Morawska & Milton, 2020; Morawska et al., 2023; Noorimotlagh et al., 2021; Prather et al., 2020).

Expert warnings were accompanied by studies suggesting airborne transmission in hospitals, restaurants, gyms, buses, apartment buildings, churches, and hotels; studies demonstrating that people release fine aerosols when breathing, talking, or singing; and studies that sampled viable SARS-CoV-2 virus from the air (Coleman et al., 2021; Public Health Agency of Canada, 2021b). In addition, scientists explored the dynamics of the COVID-19 pandemic itself to demonstrate that COVID-19 is airborne (Greenhalgh et al., 2021).

At the same time, scientists, engineers, and knowledge translation workers shared guidance on mitigation measures such as ventilation and filtration (Allen & Ibrahim, 2021; American Society of Heating, Refrigerating and Air-Conditioning Engineers, Epidemic Task Force [ASHRAE], 2021; Department of Health, Republic of South Africa, 2021; Morawska et al., 2020; Office of the Chief Science Advisor of Canada, 2020; Public Health Agency of Canada, 2021a, 2021c; REHVA, 2021). Scientists also suggested that improved indoor air quality measures could mitigate the increased use of chemical disinfectants on health, and published studies demonstrating that filtration removes SARS-CoV-2 RNA from the air (Domínguez-Amarillo et al., 2020; Rodríguez et al., 2021).

In Ontario, expert warnings were accompanied by media discussion about the role of ventilation and filtration in mitigating COVID-19 transmission in settings such as hospitals, food processing plants, and schools (Glowacki, 2020, 2021; Mojtehedzadeh, 2021; Mojtehedzadeh & Warren, 2021; Tubb & Wallace, 2021).

The precautionary principle and public health in Ontario

Even before there was incontrovertible evidence that SARS-CoV-2 transmits through the air, public health authorities had the option of applying the ‘precautionary principle’, which prescribes ‘anticipatory action to protect against a potential harm before definitive evidence of the harm materializes’ (Weir et al., 2010). Public health authorities in Ontario had a particular imperative to take this approach. In 2003, there was an outbreak of SARS-CoV-1 in Ontario, after which an independent commission examined the performance of Ontario’s public health system. In the final report, Commission lead Archie Campbell wrote:

If the Commission has one single take-home message it is the precautionary principle that safety comes first, that reasonable efforts to reduce risk need not await scientific proof. (Campbell, 2006, p. 13)

Campbell emphasized in particular that public health authorities should have adopted the precautionary principle in the face of potential airborne transmission of SARS-CoV-1 (Campbell, 2006, p. 11).

While the precautionary principle can limit harm, all interventions, including those with the stated goal of ‘care’, have the potential to reproduce the dynamics of oppression and advantage in a specific jurisdiction (Murphy, 2015).

For example, in March 2020, Ontario granted emergency powers to police and other enforcement officers that included the right to demand identification from people who were out in public. This was accompanied by ‘physical distancing’ by-laws in specific municipalities. A range of organizations warned that these measures would target the same people generally subjected to harassment and violence by police and other institutions with enforcement powers. The Black Legal Action Centre stated that the new measures could lead to, ‘ … further criminalization of racialized and marginalized people, specifically Black people’ (Black Legal Action Centre, 2020). Other groups shared guidance for those likely to be targeted, warning that these measures were, ‘ … particularly dangerous for Black and Indigenous communities and [raise] the risk that migrants can be stopped, arrested, and detained … ’ (No-one is Illegal Toronto et al., 2020).

Mainstream media also pointed out the racism associated with what have been characterized by public health experts as ‘useless’ requirements for travellers from China to test before entering Canada or the USA (Huang, 2023). Others raised concern about the ways that governments in Italy, the USA, and elsewhere, ‘… misappropriated the COVID-19 crisis to reinforce racial discrimination, doubling down, for example, on border policies and conflating public health restrictions with anti immigrant rhetoric’ (Devakumar et al., 2020).

Predictions that specific types of public health measures would be used to reinforce racist hierarchies proved accurate in Canada, with similar trends reported in jurisdictions such as Europe and the USA (Amnesty International, 2020; Canadian Civil Liberties Association & Policing the Pandemic Mapping Project, 2021; Devakumar et al., 2020).

Contextualizing precautionary action in order to avoid abuses would enable public health officials to identify measures with little potential to cause harm. We contend that building-level measures such as ventilation and filtration fall into this category as they: are applied outside of pandemic conditions as best practices in well-managed buildings; are associated with benefits beyond limiting disease transmission; can be implemented without targeting people for stigmatization or surveillance²; do not in themselves limit the activities of building occupants and; are associated with no known health-related harms when applied according to best practices (Bekö et al., 2008; Fisk & Chan, 2017; Myers et al., 2022).

COVID-19 and congregate settings Ontario

Airborne transmission of SARS-CoV-2 has particular implications for people who live and work in settings such as long-term care, shelters, and group homes, often termed ‘congregate settings’, in Ontario.

For example, people who live and work in long-term care have been particularly affected by COVID-19. By 30 March 2023, according to the provincial government’s data, 13 long-term care workers and more than 5,300 long-term care residents had died of COVID-19, constituting close to 32% of the officially recorded COVID-19 deaths in Ontario. These deaths continued three years into the pandemic – between 4 June 2022 and 30 March 2023, the provincial government recorded the deaths of 906 long-term care residents and two long-term care workers from COVID-19 (Government of Ontario, 2023).³

Beyond long-term care homes, we know of no sources of systematic, province-wide data broken down by type of facility and including both COVID-19 case counts and deaths. However, reports from mainstream media, independent journalists, and academic researchers suggest outbreaks in facilities such as shelters, correctional facilities, and group homes for adults with disabilities have been severe (Draaisma, 2021; Loreto, 2021; Prison Pandemic Partnership, 2021).

Airborne transmission of SARS-CoV-2 in congregate settings in Ontario has particular implications for health equity. The Canadian state and its institutions, by way of inter-related structures, processes and ideologies such as colonization, white supremacy and ableism, determine the populations that are compelled to live in settings such as long-term care, group homes, shelters and detention centres, and the populations that are generally able to avoid them.

For example, in Canada and other settler colonial contexts, state-sponsored colonial dispossession and white supremacy actively produce different types of homelessness and forced institutionalization, although these attempts have always faced constant, courageous, and creative resistance (Allan & Smylie, 2015; Harris & Forrester, 2003; Reece, 2020; Thistle, 2017; Thurber et al., 2021; United Nations Working Group of Experts on People of African Descent, 2017). State-sponsored or sanctioned activities that facilitate the ongoing process of Canada’s brand of settler colonization lead both directly and indirectly to various types of institutionalization and loss of home.

Importantly, colonial dispossession and white supremacy are tools of both oppression and advantage – they are designed to enrich white, settler populations, generating direct material advantage (Nixon, 2019). As a result, white upper class individuals and communities – and in particular communities to which decision-makers belong – are generally able to avoid living or working frontline jobs in settings such as long-term care, shelters, and detention centres. They can also profit from some of these facilities, or help others to do so (Badone, 2021; CBC News, 2020).

In the context of the dynamic outlined above, the health and safety measures recommended for congregate settings have particular implications for health equity in Ontario and other jurisdictions. In addition, living and working conditions in congregate settings can put both residents and workers at particular risk of contracting COVID-19. As a result, and given PHO’s legislative responsibility to ‘contribute to efforts to reduce health inequities’, particular scrutiny should be given to the quality and timeliness of the COVID-19 guidance shared with these facilities.

Research question

PHO is mandated by legislation to share ‘scientific and technical advice and support’, ‘undertake research related to evaluating the modes of transmission of febrile respiratory illnesses’, and help ‘reduce health inequities’ (Government of Ontario, 2007). We set out to document how PHO responded to the possibility – and, eventually, the certainty – of airborne transmission during the COVID-19 pandemic in the context of its guidance for long-term care and congregate settings such as shelters. In October 2021, we reviewed PHO’s public, written COVID-19 guidance for these settings, with a focus on indoor air quality (IAQ) measures such as ventilation and filtration that have the capacity to mitigate airborne transmission.

Methods

Document review

We identified, stored and analyzed documents using largely standard document review methods (Bretschneider et al., 2017). Our research was informed by thematic analysis (TA), which seeks to identify patterns within data sets. TA emphasizes transparency, encouraging researchers to articulate assumptions and ensure readers understand how the research was done (Braun & Clarke, 2006). As result, we have included a detailed methods section, along with tables documenting our research sample. We have also listed some of our core assumptions in the section below.

TA also directs researchers to contextualize data, rather than simply present findings. To this end, we have included detailed introduction and discussion sections in order to ensure that our findings are understood: a) in the context of the authors’ understandings of concepts such as ‘health equity’; and b) in local context (for example, legislative context). In addition, TA emphasizes the agency of the researcher, and discourages passive framings such as ‘themes emerged’ (Braun & Clarke, 2006, p. 80). In response, we have shared both our research decisions and conceptual understandings throughout this paper.

Finally, TA is an iterative process, moving back and forth across stages of data collection and analysis. Co-authors spent months revisiting every stage of the research as described below, and adding layers of context as a group.

Assumptions

TA encourages researchers to articulate the assumptions that shaped their study (Braun & Clarke, 2021). We share the assumption that public health should prioritize precautionary measures such as ventilation and filtration that are unlikely to cause harm. We also share the assumption that there is a particularly strong imperative for public health to move aggressively to protect people who are compelled by the state to live in specific types of facilities. Finally, we share the assumption that, to some degree, written guidance from PHO influences the actions of those responsible for health and safety in long-term care and congregate settings.

Document review process

Identifying and selecting documents

We explored written guidance listed in the COVID-19 ‘congregate living’⁴ and ‘long-term care’ sections of PHO’s website as of 29 October 2021. We focused on documents published on or after January 2021, as, by this time, the potential for IAQ measures to mitigate COVID-19 had been widely-discussed (see Figure S1 in the supplemental material). We then divided resources into three categories:

• General COVID-19 guidance developed specifically for long-term care and congregate settings. We excluded documents that were not guidance documents, for example, epidemiological reports. We also excluded documents that were lists of other documents.

• Topic-specific COVID-19 guidance developed specifically for long-term care and congregate settings (e.g. resources on personal protective equipment). Where a topic encompassed a range of potential mitigation measures (for example, cohorting) it was included in the category of ‘general guidance’.

• COVID-19 checklists. In this section, we set out to compare guidance for long-term care and congregate settings with parallel guidance for other settings. To do this, we chose PHO’s COVID-19 ‘checklists’, which share a relatively standard format. Each checklist identifies its audience and purpose, and then provides an itemized checklist divided into categories. Each item on the checklist has a section for notes, or in which to mark ‘yes’ or ‘no’ beside a particular measure, presumably so the person auditing the facility can check off measures that are in place, and identify measures that still need to be implemented. Some checklists also include signature areas for positions such as public health staff, inspectors, facility administrators, or facility staff. To identify all relevant checklists, we used the search filter function on PHO’s website, filtering for ‘type of resource’ (checklist) and ‘topic’ (COVID-19).

See Figure S2 in the supplemental material for a flow chart illustrating our approach to document selection.

Reviewing resources

Key word search

We searched each resource in the ‘general guidance’ and ‘checklist’ categories for the following key words: air, airborne, aerosol(s), HVAC, ventilation, ventilate, filtration, filter, HEPA, portable, exhaust, fan, window(s), ultraviolet, and UV. We chose these key words because best practices for reducing airborne transmission of COVID-19 through improvements to indoor air quality include ventilation, filtration, and, in some cases, ultraviolet disinfection (Allen & Ibrahim, 2021; ASHRAE, 2021; Morawska et al., 2020). We began to identify these keywords through our pilot rapid review of COVID-19 guidance recommended by Toronto Public Health (Katz et al., 2021).

To conduct the search, we used the search function in Adobe PDF software, and selected the ‘stemming’ option, which highlights all words that include any segment of the search term. For example, a search for ‘ventilation’ will include ‘ventilate’ and ‘ventilated’. We also read each document in these categories to ensure we did not miss key words through the electronic search.

Qualitative review

We read each document in the ‘general guidance’ and ‘checklists’ category to explore its approach to indoor air quality. We were also interested in the question of which mitigation measures were emphasized. Finally, we read the ‘revisions’ section of each document to identify changes to guidance over time.

We did not conduct detailed qualitative reviews for topic-specific guidance, since the titles generally made their focus clear (e.g. guidance on personal protective equipment).

Storing resources

Many documents cited in this study have been updated or changed on the PHO website. While some updated documents provide revisions with a complete list of version dates, others do not. For this reason, we stored copies of the documents from our sample, current at the time of the study.

Findings

Guidance designed for long-term care homes and congregate settings

We identified 11 COVID-19 guidance documents developed specifically for long-term care homes (n. 5) and congregate settings (n. 6). Of these, nine were general guidance documents and two were topic-specific guidance documents. Documents were in different formats, and content often overlapped. Document formats, as named by PHO, were as follows: ‘at a glance’ (n. 4), ‘checklists’ (n. 3), ‘best practice’ (n.1), ‘environmental scan’, (n. 1), ‘infographic’ (n.1) and ‘reference guide’ (n. 1).

In the 11 documents in our sample, there were no references to IAQ measures. Instead, resources emphasized measures such as: personal protective equipment, entrance screening, cohorting, surveillance and communication, vaccination, symptom-monitoring, hand hygiene, respiratory etiquette (such as covering mouth and nose with sleeve while sneezing), cleaning and disinfection, and physical distancing, including the use of physical barriers, floor markers, or signage to keep people two metres apart. Several resources emphasized the need for private bedrooms and bathrooms for people with confirmed or suspected cases of COVID-19. To mitigate transmission when private spaces were not available, some of these same resources suggested barriers such as curtains in bedrooms, sleeping head-to-toe, and cleaning and disinfecting bathrooms between cohorts.

Many resources stipulated the need for ‘droplet and contact’ as opposed to ‘airborne’ precautions. At the time of the study, PHO’s description of droplet and contact precautions included gloves, gowns, eye protection, and surgical masks (Public Health Ontario, 2020).

Of the 11 documents in our sample, six had undergone one or more revisions, some as recently as September 2021.

See Table S1 in the supplemental material for a full list of resources included in this section.

Comparing COVID-19 checklists

The nine checklists included in this category had varying foci. Some were focused on planning, others on COVID-19 outbreaks, and still others on daily operations (see Table S2 in the supplemental material). All, however, included sections on general infection prevention and control, and were interactive documents designed to direct the activities of the reader. We focused on the most recent revisions of each checklist published up to 29 October 2021.

We identified two COVID-19 checklists for congregate settings (both revised May, 2021) and one for long-term care and retirement homes (revised September, 2021). These resources did not contain references to IAQ measures. (Please note, these checklists were also included in our primary sample as analyzed in the previous section.)

We identified one COVID-19 checklist for schools (revised September, 2021). This checklist contained a dedicated section on IAQ, which included references to HVAC systems, natural ventilation and portable air filters.

We identified one COVID-19 checklist for clinical office practice (revised September, 2021). This checklist contained a dedicated section on HVAC systems listing specific HVAC standards. It suggested that if HVAC systems did not meet these standards, facility managers should consider mitigation measures such as open windows or air filtration.

We identified two COVID-19 checklists for day camps (both published May, 2021), and two for overnight camps (both published June, 2021). Checklists focused on pre-camp planning suggested the need to designate a well-ventilated area for isolation. Checklists focused on daily operations suggested opening windows and tent flaps to increase natural ventilation, and ensuring HVAC systems (if applicable) were regularly maintained.

Please see Table S2 in the supplemental material for all checklists.

Additional guidance

During our initial search, we identified slide presentations for two 2021 webinars listed on the relevant pages of PHO’s website. As we chose to focus on written guidance, we did not include these in our sample. We did, however, attempt to watch both. The first was not posted on the PHO website, and we could not find it through a Google search. The second was not posted on the PHO website, but we did find it through a Google search, posted on YouTube. Although the second webinar does have a slide mentioning HVAC, the discussion was focused on how to plan for infection prevention and control issues during renovations such as exposing residents to hazards.

In addition, during our initial search, we identified written documents (n = 6) posted to the ‘congregate settings’ and ‘long-term care’ pages of PHO’s website that were not designed specifically for long-term care or congregate settings, but rather for general or health care settings. Please see Table S3 in the supplemental material for a list of these documents. Three of these documents discuss IAQ measures. One was a general guidance document on HVAC in buildings during COVID-19, one was a ‘FAQ’ about ultra-violet disinfection, and one was interim guidance for health care settings that included a recommendation about reviewing HVAC systems (this document included long-term care in its definition of health care settings).

Discussion

When we conducted our analysis in October 2021, PHO had omitted references to IAQ measures from its public, written guidance specifically designed for long-term care and congregate settings. This omission, however, did not appear across all of PHO’s materials. For example, PHO had included limited references to IAQ measures in its COVID-19 checklists for schools, summer camps, and clinical offices. In addition, in March 2021, PHO published detailed guidance related to HVAC systems and COVID-19 for general audiences (Public Health Ontario, 2021b), followed by a ‘FAQ’ on ultra-violet disinfection in July 2021 (Public Health Ontario, 2021f).⁵ PHO also hosted webinars focused on indoor air quality in March 2021 and July 2021 (Public Health Ontario, 2021c, 2021d). In addition, in May 2021, PHO published an evidence synthesis focused on droplet and aerosol transmission which included a recommendation to ‘ensure ventilation systems are well-maintained and optimized … ’ (Public Health Ontario, 2021a, p. 15).

At the time of our study, PHO was recommending IAQ measures in COVID-19 checklists for some settings and not others. In addition, its own detailed recommendations around HVAC systems were not referenced in its guidance for long-term care or congregate settings.

In June 2022, close to two years after scientists first raised the alarm about airborne transmission of COVID-19, PHO began adding brief sections about ventilation and filtration to documents in our sample.^6,7 While this is a positive development, as of May 2023, IAQ-free guidance remains on PHO’s website (Public Health Ontario, 2021e). In addition, as of May 2023, PHO’s website does not feature an alert drawing attention to the fact that the organization is now recommending ventilation and filtration in its COVID-19 guidance for long-term care and congregate settings.

Evidence demonstrates that both the WHO and the US CDC failed to adequately alert their audiences to updated COVID-19 guidance reflecting the importance of airborne transmission (Jimenez et al., 2022; Molteni, 2021). Future research should focus on how and if PHO alerted congregate facilities to the new IAQ measures included in its guidance. In addition, future research should examine non-written materials such as PHO’s infection prevention and control training to see if they contain IAQ measures and, if so, when these measures were introduced, and how they are communicated.

PHO’s response to airborne transmission of COVID-19 was not unique. For example, responses from World Health Organization (WHO) and the US Centers for Disease Control were similarly slow, confusing, fragmented and incomplete, and often disregarded current scientific evidence (Morawska et al., 2023; Prather et al., 2020). Communications between scientists and WHO officials in particular demonstrate that public health authorities actively refused to incorporate relevant scientific expertise into their general pandemic responses (Jimenez et al., 2022; Molteni, 2021; Morawska et al., 2023). What this paper demonstrates, however, is that PHO provided a specific set of facilities such as shelters, detention centres, and long-term care with particularly inadequate COVID-19 guidance.

Next steps

PHO is mandated by legislation to share ‘scientific and technical advice and support’, ‘undertake research related to evaluating the modes of transmission of febrile respiratory illnesses’, and help ‘reduce health inequities’. In the context of its written, public, COVID-19 guidance to long-term care and congregate settings, PHO did not meet this mandate. As a result, next steps should focus on accountability, with an emphasis on regulatory and legal remedies.

One step would be to ensure all branches of Ontario’s public health system have independence from both government and the private sector (Campbell, 2006; Fafard et al., 2018; Ogilvie, 2023). Another would be to develop mechanisms to ensure PHO and its leaders can be held accountable when the organization does not meet its legislated responsibilities.

In Ontario, engineers, physicians, scientists, and many others appealed to individual public health leaders through direct communication, open letters, and opinion pieces (Glowacki, 2020; O’Campo et al., 2022). Following these activities, there were no explicit appeal mechanisms built into the legislation that governs PHO (Government of Ontario, 2007).

A similar dynamic played out internationally, as scientists attempted to convince the World Health Organization to address airborne transmission (Morawska et al., 2023). Based on these experiences, Morawska and colleagues offer a series of recommendations including the following: ‘Multidisciplinary mechanisms should be created by which decision-makers should be accountable for using or rejecting science, in a transparent and timely manner’ (Morawska et al., 2023, 1858). For PHO to function effectively, there must be formal, independent, arms-length mechanisms in place to hold the organization and its leaders accountable to its legislated mandate.

Limitations

It is possible that some relevant resources on PHO’s website were not listed on their ‘congregate living’ and ‘long-term care’ pages. As a result, it is possible that we did not capture all of PHO’s public, written guidance for congregate settings. Searches such as ‘COVID-19’ and ‘long-term care’ or ‘COVID-19’ and ‘congregate settings’ on PHO’s website generated several dozen entries, often for resources that overlapped in content, and with little indication as to which document was the most comprehensive or definitive. In addition, Google searches might have turned up additional resources.

We assumed, however, that workers, facility managers, and inspectors would not sift through the dozens of search results, but rather focus on guidance, and especially the checklists, posted on relevant areas of the organization’s website. We also contacted PHO by email in October 2021 informing them of the results of an earlier pilot review; alerting them to this study; and asking if there were materials they would like us to review⁸ (Katz, October 19, 2021). We did not receive a response to our question.

We also assumed guidance produced by PHO has some impact on long-term care and congregate settings. This study, however, did not explore the extent to which PHO guidance influences those responsible for health and safety in specific facilities. An earlier pilot review did find, however, that PHO’s guidance heavily influenced advice provided by some local Public Health Units to facilities such as shelters (Katz et al., 2021). Future research may wish to explore where facility operators go for guidance they consider to be useful, definitive, and/or binding.

In addition, we did not look at all recent guidance for our comparator settings of schools, summer camps, and clinical offices. It is possible that the guidance we looked at was not representative of what PHO was sharing with these settings at the time of our study. We made the assumption, however, that COVID-19 checklists were likely to be representative documents, given that they are designed to coordinate action by those responsible for health and safety.

We should also note that while COVID-19 checklists for schools, summer camps, and clinical offices included some IAQ measures, this guidance could also be classified as ‘sub-standard’. For example, none of these checklists recommended portable air filtration or bathroom fans. As a result, comparisons generated by our study may serve to overstate the quality of the guidance provided to settings such as schools.

Conclusion

Many of the issues outlined in this paper were explored 17 years ago by the Ontario SARS Commission report, through which runs a tone of desperation and anger in response to the preventable loss of human life. The Report author Archie Campbell pleads with decision-makers in Ontario not to wait for certainty to protect people’s lives from airborne transmission during the next pandemic, writing:

Those who argued against the N95, which protects against airborne transmission, believed SARS was spread mostly by large droplets. As a result, they said, an N95 was unnecessary except in certain circumstances and a surgical mask was sufficient in most instances. They made this argument even though knowledge about SARS and about airborne transmission was still evolving. That more and more studies have since been published indicating the possibility under certain circumstances of airborne transmission, not just of SARS but of influenza, suggests the wisdom and prudence of taking a precautionary approach in the absence of scientific certainty. (Campbell, 2006, p. 11)

As evidenced by our study, PHO did not apply the Ontario SARS Commission’s findings and take a precautionary approach in the face of potential airborne transmission of SARS CoV-2. Instead, PHO omitted basic IAQ measures such as ventilation and filtration from its public, written guidance for long-term care and congregate settings until at least June 2022, more than two years into an airborne pandemic.

The legislation that governs PHO tasks the organization with the responsibility to help ‘reduce health inequities’. This review, however, illustrates how PHO’s guidance contributed directly to health inequity during the COVID-19 pandemic. Future research should explore whether this same dynamic played out in other jurisdictions.

Acknowledgements

Thank you to Jessica Demeria, Kimberly Devotta, Melissa Goldstein, and Kate Francombe-Pridham for generously sharing your knowledge and insight during early stages of this work. Thank you to Karissa Avignon for your thoughtful and painstaking review of our data. Thank you to Pearl Buhariwala for your invaluable contributions to this project. Thank you to Jo-Ann Osei-Twum, Paula Chidwick and Victoria Arrandale for helping us think through specific public health, bioethical, and citation questions related to this manuscript. Thank you to Graham Hudson for your insights into legislative questions relevant to this manuscript. Thank you to the anonymous peer-reviewers for your thoughtful reading of our work and your important questions and suggestions. Your input significantly influenced the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/09581596.2023.2262736.

Additional information

Funding

Financial support for this work was partially provided by the School of Cities, University of Toronto and the Canadian Institutes of Health Research [PCS 183463].

Notes

1. While Canadian jurisdictions are often referred to as fixed and legitimate categories, they are the product of land theft from Indigenous nations and groups. Ownership and/or use by Canada is often asserted in contradiction to Canada’s own laws and treaty obligations, and the original agreements between Indigenous nations and groups and the British Crown. In addition, there are wide swathes of territory for which there are no treaties or agreements, and to which Canada has no claim at all. Finally, Canadian jurisdictions are not contiguous – the land labelled as Canada on most maps is not all under Canadian jurisdiction. It would be inaccurate to refer to settler jurisdictional names and boundaries in Canada without pointing to the fact that they are imposed, relatively recent and, in many cases, contested and in flux. We do not refer to jurisdictions such as Ontario to suggest these are fixed and inevitable categories. Rather, we explore the mandate and actions of PHO in the context of the current settler colonial matrix of governance that helps to determine the conditions under which many people in what is currently called Ontario work and live.

2. We note that in settings characterized by coercion, even ventilation and filtration can be used as mechanisms of surveillance and control when accompanied by certain types of indoor air quality monitoring. We emphasize, however, that indoor air quality measures can be implemented effectively without this type of monitoring using well-known and time-tested principles of ventilation and filtration.

3. For a recent history of long-term care in Ontario and the policies that impacted residents and workers during the COVID-19 pandemic, see Badone (2021).

4. At the time of the study, PHO defined congregate facilities on its website as, ‘ … facilities where people (most or all of whom are not related) live or stay overnight and use shared spaces (e.g. common sleeping areas, bathrooms, kitchens) including: Shelters; Group homes; Correctional facilities; Children or youth residential settings’ (Public Health Ontario, 2022). In most COVID-19 guidance, PHO draws a distinction between general congregate settings and long-term care. In some cases, long-term care homes are also listed as health care settings. In others, they are bundled with retirement homes. Finally, while much of the guidance for congregate settings is framed by PHO as applying to congregate settings generally (excluding long-term care), some documents state that they are not specifically developed for correctional facilities.

5. We refer to version dates of these publications as available and archived at the time of the study.

6. While our study concluded in October 2021, we periodically identified and archived relevant changes to documents in our sample up to May 2022. We continued to generally monitor documents in our sample until May 2023.

7. PHO’s public, written guidance specifically for long-term care homes and congregate settings excluded IAQ measures in October 2021. However, other public health and government agencies and ministries published guidance on IAQ measures and COVID-19 prior to that date. For example, the Public Health Agency of Canada published, ‘COVID-19: Guidance on indoor ventilation during the pandemic’, in January 2021 (PHAC, 2021a) and ‘Using ventilation and filtration to reduce aerosol transmission of COVID-19 in long-term care homes’ in April 2021 (PHAC, 2021b). As noted, PHO itself explored the use HVAC in reducing transmission of COVID-19 in March 2021 (PHO, 2021b).

8. Authors on this paper began informing people in leadership positions at PHO about these omissions in September 2021. (Email from A. Katz to Vice-President, Science and Population Health, PHO, B. Schwartz [who was one of several addressees from different organizations], Sept. 27, 2021; Email from A. Katz to Chief Health Protection and Emergency Preparedness Officer, PHO, J. Hopkins, Oct. 19, 2021; Email from A. Katz to Chief Health Protection and Emergency Preparedness Officer, Nov. 4, 2021; Email from P. O’Campo to Vice-President, Science and Population Health, PHO, Feb. 9, 2022.) As both email authors and addressees were public sector employees, relevant correspondence should be a matter of public record and should be available through Freedom of Information request as per Ontario’s Freedom of Information and Protection of Privacy Act.