Aerosol transmission & respirator masks, a PPE timeline
Aerosol transmission & respirator masks, a PPE timeline
They knew: the CDC is well aware of aerosol transmission and the ways to protect people from infectious disease using respirator masks and the precautionary principle.
September 2017
Surgical Masks (SMs)
-- Disposable coverings, loose-fitting that leave gaps between the mask and the wearer’s face through which harmful particles may pass
-- Intended to prevent transmission of infection from the wearer to others (source control)
-- Not respirators
N95 Respirators
-- Standard N95: NIOSH-approved. Designed to reduce inhalation of aerosolized
particles. Fit testing is required.
--Surgical N95: FDA-cleared as a medical device and NIOSH-approved. Designed to reduce inhalation of aerosolized particles. Fit testing is required.
-- Most N95s are disposable (single-use) and not designed for repeated or extended use.
– However, limited reuse may be permitted under certain circumstances
– EHFRs and PAPRs are designed for reuse
September 2019
Most N95s are disposable (single-use) and not designed for repeated or extended use. – However, limited reuse may be permitted under certain circumstances (e.g., extreme shortages during a pandemic) – EHMRs and PAPRs are designed for reuse
Gap in national surge needs: – ASTHO Report (2014): Total number of N95 held by U.S. acute care hospitals ≈ 60M – This means, hospitals have about 1% of expected national demand for a severe pandemic ▪ Shortages of N95 respirators occurred during SARS (2003) and H1N1 influenza (2009)
January 2020
HCP [Health Care Personnel] entering the AIIR [Airborne infection isolation room] soon after a patient vacates the room should use respiratory protection. (See personal protective equipment section below) Standard practice for pathogens spread by the airborne route (e.g., measles, tuberculosis) is to restrict unprotected individuals, including HCP, from entering a vacated room until sufficient time has elapsed for enough air changes to remove potentially infectious particles (more information on clearance rates under differing ventilation conditions is available). We do not yet know how long 2019-nCoV remains infectious in the air. In the interim, it is reasonable to apply a similar time period before entering the room without respiratory protection as used for pathogens spread by the airborne route (e.g., measles, tuberculosis). In addition, the room should undergo appropriate cleaning and surface disinfection before it is returned to routine use.
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Use respiratory protection (i.e., a respirator) that is at least as protective as a fit-tested NIOSH-certified disposable N95 filtering facepiece respirator before entry into the patient room or care area. See appendix for respirator definition.
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Consider designing and installing engineering controls to reduce or eliminate exposures by shielding HCP and other patients from infected individuals. Examples of engineering controls include physical barriers or partitions to guide patients through triage areas, curtains between patients in shared areas, closed suctioning systems for airway suctioning for intubated patients, as well as appropriate air-handling systems (with appropriate directionality, ltration, exchange rate, etc.) that are installed and properly maintained
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Facilities and organizations providing healthcare should implement sick leave policies for HCP that are non-punitive, exible, and consistent with public health guidance.
(6) CDC has issued the document, Interim Infection Prevention and Control Recommendations for Patients with Known or Patients Under Investigation for 2019 Novel Coronavirus (2019‐ nCoV) in a Healthcare Setting (Attachment A), in an effort to prevent the spread of infection during healthcare delivery. This guidance is not intended for non‐healthcare settings (e.g., schools) OR to persons outside of healthcare settings.
(7) This guidance is based on the currently limited information available about 2019‐nCoV related to disease severity, transmission efficiency, and shedding duration. This cautious approach will be refined and updated as more information becomes available and as response needs change in the United States.
(8) The CDC has also provided two checklists: Hospital Preparedness Checklist (Attachment B) and Healthcare Providers Preparedness Checklist (Attachment C). These are available to aid healthcare facilities in preparing to receive and evaluate potential cases or persons under investigation (PUIs)s for 2019‐nCoV.
March 2020
That is focused on two things. One, we do not know the extent of contribution that environmental virus might pose. And so the glove and gown use is with an eye towards ensuring that we don't accidentally transmit infection that way. Eye protection is something that we, I think, culturally for a generation or more, have been lax about. I think that's, frankly unacceptable in routine times, given that influenza spreads wildly across our community every year. And so this, as well as for routine practices, is an opportunity to firm up our use of eye protection. It's not about there being necessarily target epitopes in the conjunctiva. It's the fact that our eyes drain into the back of our throats and if you're trying to keep respiratory viruses out of your throat, then protecting your eyes makes sense. Nose and mouth, similarly, need to be protected. We use respirators in this context because of the very likely possibility of a contribution of near range inhalation. This is something we've talked about with every concerning respiratory infection over the past 20 years. And that is the idea that when we cough or breathe, we generate a range of particle sizes. Some of them are big and splashy and can land directly on us. But if you're not within line of sight or ballistic range - but within about six feet - it's conceivable that somebody can be generating small particles with infectious material in them, that could drift in and be breathed and entrained in what you're inhaling. For that reason, a surgical mask that's a nice barrier against ballistic impact, isn't as good of a device. The fact that there's a half-inch gap on either side of your face really doesn't protect against inhalation. And so that's why we recommend respiratory protection. There is - there's always discussion of the available published evidence and ongoing generation remedies, that question what is the relative benefit of a mask versus a respirator. And I think the jury is still out. It seems to be fairly close, when we've compared respiratory infections across the board. But then again, there's always a question of adherence. And what we see is that people are much more likely to adhere correctly to surgical mask use than to respirator use. So that behavioral component is a bit of a question mark. We also are hearing early information about public issues that are upcoming that might show a lean towards maybe a little bit more protection with a respirator. So, I think we as a profession will continue to have to navigate that grey zone. But for the time being, that is the recommendation that we made during the containment phase.
Guidance on Preparing Workplaces for COVID-19 OSHA 3990-03 2020
Engineering Controls
Engineering controls involve isolating employees from work related hazards. In workplaces where they are appropriate, these types of controls reduce exposure to hazards without relying on worker behavior and can be the most cost-effective solution to implement. Engineering controls for SARS-CoV-2 include:
Installing high-efficiency air filters.
Increasing ventilation rates in the work environment.
Installing physical barriers, such as clear plastic sneeze guards.
Installing a drive-through window for customer service.
Specialized negative pressure ventilation in some settings, such as for aerosol generating procedures (e.g., airborne infection isolation rooms in healthcare settings and specialized autopsy suites in mortuary settings).
Administrative Controls
Administrative controls require action by the worker or employer. Typically, administrative controls are changes in work policy or procedures to reduce or minimize exposure to a hazard. Examples of administrative controls for SARS-CoV-2 include:
Encouraging sick workers to stay at home.
Minimizing contact among workers, clients, and customers by replacing face-to-face meetings with virtual communications and implementing telework if feasible.
Establishing alternating days or extra shifts that reduce the total number of employees in a facility at a given time, allowing them to maintain distance from one another while maintaining a full onsite work week.
April 2020
Reusable respirator masks could be a lifeline for health care workers trying to protect themselves while treating coronavirus patients. They provide the same level of protection as disposable N95 respirators, which are in short supply around the world. They can be easily disinfected between patients and shifts. And they last for months. But the nation’s emergency supply of medical equipment never stocked them, despite years of research predicting dire shortfalls of disposable respirators during a pandemic and recommendations to stockpile reusable ones. The decision not to buy them for the Strategic National Stockpile is inexplicable to Tom Frieden, who led the U.S. Centers for Disease Control and Prevention until 2017.
SARS-CoV-2 remained viable in aerosols throughout the duration of our experiment (3 hours), with a reduction in infectious titer from 103.5 to 102.7 TCID50 per liter of air. This reduction was similar to that observed with SARS-CoV-1, from 104.3 to 103.5 TCID50 per milliliter (Figure 1A).
May 2020
The Food and Drug Administration (FDA) issued an emergency use authorization (EUA) for the system on March 28, 2020, enabling hospitals, health systems, and states to use the system to decontaminate and reuse PPE.1 Unfortunately, this system may not work as advertised, and recent reporting calls into question whether the FDA succumbed to political pressure in extending the EUA. Millions of taxpayer dollars and the lives of an untold number of frontline healthcare workers are potentially at risk if the CCDS does not perform as expected. The CCDS is manufactured by Battelle Memorial Institute based in Columbus, Ohio. The company claims their system “can decontaminate thousands of N95 respirators using concentrated, vapor phase hydrogen peroxide.”2 The system can allegedly “decontaminate the same respirator multiple times without degrading N95 respirator performance.”3 The company submitted a request for an EUA to the FDA, with strong and public support from Ohio Governor Mike DeWine, President Donald Trump, and multiple members of the Ohio Congressional Delegation.
Dr. Howard: “I think one of the issues I'd like to emphasize at the get-go is that decontamination of an N95 respirator is not the first step in optimizing the use of respirators for healthcare workers. It is literally the last step. Every other type of respirator that we recommend in healthcare - a PAPR and elastomeric, etc - be used before you decide to decontaminate your supply of N95s.”
Ms. Wild: “Ms Sweatt in your March 19th letter to Chairman Scott and Representative Adams you stated that an emergency temporary standard is not needed to protect health care workers or other workers because the healthcare industry fully understands the gravity of the situation and is taking the appropriate steps to protect its workers. But we know that close to 62,000 health care workers have been infected with COVID-19 and 291 are dead as of last count. I suspect that some hospitals are safer than others would you agree with me on that? for workers? You don't okay you need to turn on your mic but you you don't have an opinion one way or the other. I know that we have two excellent healthcare institutions in my Pennsylvania district that have taken worker safety very very seriously. On the other hand we have another hospital where employees have reached out to me with deep concerns about their lack of PPE, the need to reuse surgical masks the paper masks like the one I'm wearing now over and over again. Wouldn't an OSHA standard ensure that all of our healthcare workers safe while caring for the rest of us?”
Ms. Sweatt: “Well I think if you're talking about respirators respiratory protection is already required and so it really becomes access to respirators.”
Hundreds of thousands of respirator masks to protect against coronavirus have been sent through a decontamination system that has triggered warnings from front-line workers and has so far cost the government more than $110 a mask. The system is made by Battelle Memorial Institute, a nonprofit research corporation that has built more than 50 mask-decontamination units after getting more than $400 million in federal government contracts. Battelle said its process allows for N95 respirator masks to be reused 20 times.
August 2020
The Biden Plan to Combat Coronavirus (COVID-19) and Prepare for Future Global Health Threats
Work with businesses to expand production of personal protective equipment, including masks and gloves, and additional products such as bleach and alcohol-based hand sanitizer. Incentivize greater supplier production of these critically important medically supplies, including committing, if necessary, to large scale volume purchasing and removing all relevant trade barriers to their acquisition. Task the U.S. Department of Justice with combating price gouging for critical supplies.
February 2021
In the midst of a national shortage of N95 masks, the U.S. government quietly granted an exception to its export ban on protective gear, allowing as many as 5 million of the masks per month to be shipped overseas. The Federal Emergency Management Agency issued the waiver in the final moments of Donald Trump’s presidency last month, allowing a Texas company to export its products after it failed to secure U.S. customers, according to the FEMA letter obtained by KHN. National Nurses United president Zenei Triunfo-Cortez called the export waiver “unconscionable” and said N95s remain under lock and key in many hospitals. She said she still has to “beg” for a new N95 if hers gets soiled during a shift caring for covid-19 patients.
Internal government emails obtained by The Associated Press show there were deliberate decisions to withhold vital information about new mask manufacturers and availability. Exclusive trade data and interviews with manufacturers, hospital procurement officials and frontline medical workers reveal a communication breakdown — not an actual shortage — that is depriving doctors, nurses, paramedics and other people risking exposure to COVID-19 of first-rate protection.
Before the pandemic, medical providers followed manufacturer and government guidelines that called for N95s to be discarded after each use, largely to protect doctors and nurses from catching infectious diseases themselves. As N95s ran short, the Centers for Disease Control and Prevention modified those guidelines to allow for extended use and reuse only if supplies are “depleted,” a term left undefined.
Hospitals have responded in a variety of ways, the AP has found. Some are back to pre-COVID-19, one-use-per-patient N95 protocols, but most are doling out one mask a day or fewer to each employee. Many hospital procurement officers say they are relying on CDC guidelines for depleted supplies, even if their own stockpiles are robust.
May 2021
Walensky’s announcement has a few caveats. She warned that people who are immune compromised should speak with their doctors before giving up their masks. The requirement to wear masks during travel – on buses, trains, planes and public transportation – still stands, Walensky said.
March 2022
Fourth, during the infectious period of person A, several episodes of simultaneous door-opening occurred between the rooms occupied by person A and travel group BCDEF, meaning that for a short time no barriers to the spread of airborne respiratory aerosols between these rooms were in place. Fifth, during the episodes of simultaneous door-opening, person A and the member of travel group BCDEF who opened the door should have been wearing medical masks, as is mandated within the MIF. The wearing of medical masks, short duration of simultaneous door-opening, and separation by >2 meters makes transmission by droplets improbable. Sixth, the risk for fomite transmission of SARS-CoV-2 by shared surfaces is already thought to be low (3). Person A and travel group BCDEF had no direct contact with each other or with any shared objects, as corroborated by security camera footage, making transmission by fomites in this case also improbable.
On March 22, 2022, OSHA announced a limited reopening of the record, permitting the submission of additional comments from stakeholders to the rulemaking docket (OSHA-2020-0004) until April 22, 2022. Stakeholders were also invited to submit a notice of intention to appear (NOITA) to testify during the informal public hearing.
April 2022
“OSHA has a statutory responsibility, statutory requirement to have an open and transparent process like we are having today to just determine what the standard should be. CDC is a black box. We have no idea how these recommendations are determined. Unfortunately, until there are, there are Freedom of Information Act requests or Congressional inquiries. So given all those things, it's really incumbent upon OSHA to develop standards, and to say these are the standards that every employer covered by the standard must follow.”
August 2022
Nicolas Smit @PPEtoheros 8:58 AM · Jun 10, 2023, post on twitter
After my August 2022 meeting with the White House where I once again complained about the online censorship & failure to ensure it was well known the N95 shortage was over, the FDA issued a quiet online statement explaining N95 shortages were finally over.
Today, the U.S. Food and Drug Administration announced the removal of N95 respirators from the agency’s medical device shortage list, signaling that demand or projected demand for this type of face protection device commonly used in health care settings no longer exceeds the supply. This action is the result of increased domestic manufacturing of N95 respirators, as well as updates to the FDA’s supply chain assessment based on engagement with industry and federal stakeholders, and the Centers for Disease Control and Prevention’s National Institute for Occupational Safety and Health’s (NIOSH) approval of new disposable N95s and reusable respirators.
October 2022
First, CDC issues extensive infection control guidance, but that guidance, unlike OSHA standards, is voluntary. CDC cannot cite or penalize healthcare employers for non-compliance. In addition, worker advocates would dispute whether CDC adequately protects workers’ health. While the National Institute for Occupational Safety and Health (NIOSH) falls under CDC’s umbrella, NIOSH is not generally allowed to play a leading role in establishing CDC guidance that affects healthcare workers. Nevertheless, to ensure federal government consistency, OSHA’s regulatory and enforcement actions cannot be in conflict with CDC’s guidance and CDC generally carries a bigger stick than OSHA when it comes to hashing out potential conflicts. So if CDC unexpectedly changes its guidance in the middle of OSHA’s rulemaking, OSHA is sent rushing back to the drawing board to make appropriate modifications. Issuance of OSHA’s original COVID ETS, for example, was repeatedly delayed because CDC would change its infection control guidance.
Since wearing masks or respirators can prevent spread of COVID-19, people who have a household or social contact with someone at risk for getting very sick with COVID-19 (for example, a student with a sibling who is at risk) may also choose to wear a mask at any COVID-19 Community Level. Schools and ECE programs should consider flexible, non-punitive policies and practices to support individuals who choose to wear masks regardless of the COVID-19 Community Level.
February 2023
Masks in Healthcare Published February 23, 2023, PeoplesCDC.org
As healthcare workers, patients, parents, and caregivers, we at the People’s CDC urge public health officials and healthcare organizations, including hospitals, clinics, physician and dentist offices, nursing homes, and home health care services to require masking in all healthcare settings, and to provide masks (ideally N95 respirators) for everyone in those settings. The revised CDC guidance,1 which permits patients and staff in healthcare to stop masking when “levels of Community Transmission” are not “high,” is dangerous, unethical and based on flawed data.
April 2023
Too Many Deaths, Too Many Left Behind: A People’s External Review of the CDC - PeoplesCDC.org
When the CDC announced it was conducting an internal review in 2022, we launched a People’s Review of the CDC. We surveyed nearly 500 public health experts and community leaders and reviewed over 200 journal articles, government reports, news articles and white papers. We found that the CDC prioritized individual choice and short-term business interest over sharing accurate scientific evidence with the public and protecting population health.
May 2023
If you or your family member are at high risk for severe illness, wear a mask or respirator with greater protection in public indoor spaces if you are in an area with a high COVID-19 hospital admission level. Talk with your healthcare provider about wearing a mask in a medium COVID-19 hospital admission level.
If you have symptoms consistent with COVID-19 and you are aged 50 years or older OR are at high risk of getting very sick, you may be eligible for treatment. Contact your healthcare provider and start treatment within the first few days of symptoms. You can also visit a Test to Treat location. Treatment can reduce your risk of hospitalization by more than 50% and also reduces the risk of death.
August 2023
There is a dangerous new government policy being proposed which could harm healthcare workers and patients across the country. Instead of strengthening infection control policies in healthcare settings to protect workers and patients from infectious diseases such as COVID-19, Middle East Respiratory Syndrome (MERS), and future pandemic pathogens, the CDC is planning future guidance which could lower healthcare infection control standards. The CDC’s Healthcare Infection Control Practices Advisory Committee (HICPAC) advises the CDC on infection control policies, but committee meetings are subject to almost no public scrutiny and policies are made with minimal input from patients or healthcare workers.
The CDC doesn't want you to know that they are planning to weaken infection control guidance, which means that you will be at higher risk for infection if you visit or work at a hospital, clinic, or nursing home. We're talking about any kind of infection here. Measles, tuberculosis, COVID, influenza. My name is Jane Thomason. I work on the health and safety team at National Nurses United, the largest labor union and professional association for registered nurses in the US. I've been tracking this process at the CDC for over a year. The CDC Advisory Committee on Healthcare Infection Control Practices plans to vote in August to Roll Back Measures to Prevent Transmission from Infected Patients, like isolation and ventilation. The CDC advisory committee is ignoring decades of scientific research in making weak guidance on respiratory Protection for healthcare workers. They plan to adopt the crisis standards approach from the COVID pandemic for all of infection control. The crisis standards approach allowed and encouraged employers to race to the lowest standard to save money while not protecting healthcare workers and patients, all while saying they were following the CDC guidance. Why is the CDC doing this, you ask? It's because the advisory committee is run by healthcare corporations and infectious disease clinicians. Their working group meetings are closed to the public. They have no mechanism to consult direct care nurses, other healthcare workers, patient advocates, unions, other experts. The COVID pandemic showed us that healthcare employers care more about their bottom lines. than about protecting nurses and patients. The CDC was complicit in that. Take action. Sign our petition to tell the CDC it's Past Time to Protect Patients and nurses and other Healthcare Workers. It's past time to recognize the science on aerosol transmission.
Forbes - CDC Poised To Weaken Masking, Infection Control - Judy Stone Aug 21, 2023
The planned HICPAC revisions will water down infection control protections, particularly for aerosol transmission and MDRO (multiply drug-resistant organisms). Most immediately worrisome is their conclusion that plain surgical masks (aka “baggy blues”) are equivalent to N95s and provide adequate protection to healthcare workers and patients. There is abundant evidence to the contrary. It is clear that N95s offer far better protection against aerosols, such as from Covid-19, and other inhaled pathogens. Why are they ignoring this?
People’s CDC Recommendations for CDC / HICPAC - For Immediate Release - AUG 21, 2023
Over 900 occupational safety, aerosols science, public health, and medical experts have written to new CDC Director Mandy K. Cohen, MD, MPH, informing her that CDC’s Healthcare Infection Control Practices Advisory Committee (HICPAC) must correct their review on COVID infection control measures to reflect the science of aerosol transmission through inhalation and their decision-making process must include patient advocates, infectious disease transmission scientists, aerosols scientists, healthcare personnel (providers and other frontline workers such as cleaning crews), union representatives, and occupational safety and health experts. HICPAC is a CDC committee that oversees policies and protocols on the prevention of infectious diseases in healthcare settings.