The Late-Summer Surge Is On
In mid-June, the U.S. was registering just 12,000 new cases of COVID-19 a day. On Aug. 14, the seven-day average had reached 130,000 in a surge that looks similar to that of last summer – except that this time the magnitude is greater (the surge of summer 2020 topped out at 67,000), and more young people are getting sick. This year’s late-summer surge is particularly disturbing because more than half the population is fully vaccinated, compared with zero a year ago. The disparity is almost certainly the result of the Delta variant, which is twice as transmissible as the original Wuhan strain of SARS-CoV-2, according to the American Society for Microbiology.
If the U.S. pattern in 2020 holds again this year, we can expect daily cases to start declining soon, then picking up again in mid-September and climbing to another peak in January or February. These ups and downs appear correlated to interior activity, with Americans in the South moving indoors in July to escape the heat, and those in the North going inside in the fall to escape the cold. Right now, it’s hot almost everywhere, and, according to the Centers for Disease Control (CDC), 2,691 counties are experiencing a “high” level of community transmission, compared with 200 counties deemed “low” or “moderate.” With just a few exceptions, the low and moderate counties are all in the northern part of the United States. Below is the CDC’s community-spread map as of Aug. 9, with low and moderate in blue and yellow, respectively.
Consider Florida, where COVID hospitalizations just set a record. Florida has 6% of the U.S. population but is responsible for 18% of all COVID cases, and Florida’s case positivity rate is an astounding 18.9%, up from 3.6% just a month earlier. The rate for children aged 12 to 18 is 20.1%. Low overall vaccination rates don’t explain Florida’s surge. According to the latest report from Florida’s Department of Health, some 63% of Floridians have had at least one shot, compared with 58% nationwide, and 53% of Floridians are fully vaccinated, compared with 50% nationwide. In addition, 85% of Floridians over age 85 have received at least one shot.
Vaccines appear effective in reducing hospitalizations and deaths, but Delta leaves even people who have received shots vulnerable to infection, and the vaccinated can then pass the virus on to the unvaccinated. Research published in the New England Journal of Medicine on July 21 by Jamie Lopez Bernal of Public Health England and colleagues concluded, “Only modest differences in vaccine effectiveness were noted with the delta variant as compared with the alpha variant after the receipt of two vaccine doses. Absolute differences in vaccine effectiveness were more marked after the receipt of the first dose.” But a later study showed a big drop in effectiveness for the Pfizer vaccine even after two doses. (See more on both of these studies below.) Some 49% of Americans – and all young children – are not fully vaccinated, and they are particularly susceptible indoors, where the SARS-CoV-2 virus spreads more easily. Interior mitigation efforts have still not caught with the potency of the pathogen.
Learning To Live With COVID
The fact is that COVID-19 is not going away soon, and the world is learning to live with it as a long-term disease that requires adaptation, as much as we wish for eradication. Treatment has gotten better, and, while deaths are rising, at a seven-day daily average of 687 on Aug. 14, mortality is far lower than during previous peaks. But the point is that governments, businesses, and individuals are changing behavior as the effects of the virus change in their own communities.
The biggest change is that Centers for Disease Control (CDC) shifted its earlier guidance that people who have been vaccinated did not need to wear masks indoors. Instead, on July 28, the CDC urged vaccinated Americans to “Wear a mask in public indoor settings if they are in an area of substantial or high transmission.” A cascade followed.
The Wall Street Journal reported on Aug. 8 that “up until a few weeks ago, corporate leaders felt confident about what to expect this fall” as the COVID-19 pandemic receded. But “the swift, startling resurgence of swift, startling resurgence of COVID-19 cases and hospitalizations across the U.S. is causing corporate leaders to rip up playbooks for the next few months.” The Journal continued:
No longer is a September return a target for many companies. Some employers, such as banking giant Wells Fargo & Co. and managed-care company Centene Corp., have in recent days shifted return-to-office dates to October. Meanwhile, a range of other prominent companies now predict it will be 2022 until most workers return.
In a policy change, Tesla is now requiring masks at its giant battery facility even for workers who are vaccinated. The New York Auto Show, which was set to start Aug. 20, has been cancelled. New Orleans Jazz Fest, set for October, has now been pushed to the spring of 2022. And in a policy updated Aug. 5, the CDC issued guidance stating, “Due to the circulating and highly contagious Delta variant, CDC recommends universal indoor masking by all students (age 2 and older), staff, teachers, and visitors to K-12 schools, regardless of vaccination status.” Re-masking, however, is not popular, and some governors are disputing the CDC recommendation. Ron DeSantis of Florida has even threatened to withhold the salaries of local officials who mandate masks in schools.)
The rate of vaccinations started to increase in the U.S. in the third week of July, just as cases of COVID were rising. The daily average, as of Aug. 9, was 716,000, up from 507,000 on July 20 but still far below the 3.4 million mark set in early April. The New York Times projects that, at the current pace, 85% of Americans will have at least one shot by February 2022. That forecast may be pessimistic if attitudes change with two developments: first, the imminent full approval of the Pfizer-BioNTech vaccination by the U.S. Food & Drug Administration (FDA), and, second, requirements by more and more government agencies and businesses that workers and customers be vaccinated. The Pentagon, for example, announced Aug. 9 that all military members would have to receive shots starting in mid-September.
Still, surveys by the Kaiser Family Foundation indicate that 14% of Americans have said they will not get a vaccination, period. That proportion has not budged since polling began in December 2020, but the number of Americans saying they will “wait and see” or will get vaccinated “only if required” has declined. More important, even if the FDA gives approval, it will take many months to vaccinate all children, and, increasingly, they are the ones getting sick – though, on average, not nearly as sick as adults.
Mitigating Interior Spread
Living with COVID-19 becomes a less daunting prospect not just with the advent of vaccines but also with the knowledge that there are effective ways to mitigate interior spread. Surges, happening throughout the world, have multiple sources, but a major factor is the amount of time people are spending indoors without proper protection, including not merely sufficient ventilation but also anti-viral air purification, using such technologies as advanced photocatalysis.
The evidence that the SARS-CoV-2 virus could spread easily through aerosols was at first resisted by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC). But nearly a year ago, a group of 239 scientists appealed to the medical community and international organizations that there “is significant potential for inhalation exposure to viruses in microscopic respiratory droplets (microdroplets) at short to medium distances (up to several meters, or room scale), and we are advocating for the use of preventive measures to mitigate this route of airborne transmission.” Since then, the danger of respiratory spread, especially indoors, has been widely recognized.
OSHA’s Misguided New Standards
Unfortunately, there remains confusion even in government agencies over the best ways to protect people in interior spaces. A good example is recent activity by the Occupational Safety & Health Administration (OSHA), part of the U.S. Department of Labor.
On June 21, the agency issued a “final interim rule” (ETS) to an Emergency Temporary Standard (ETS) to protect healthcare workers against COVID in their workplaces, including hospitals, nursing homes, clinics, and physicians’ and dentists’ offices. Comments on the rule face a deadline of Aug. 20, and it could be enacted shortly afterwards. “For the first time in its 50-year history,” says the filing in the Federal Register, “OSHA faces a new hazard so grave that it has killed nearly 600,000 people in the United States in barely over a year.” OSHA notes that “the [Labor] Secretary must issue an ETS in situations where employees are exposed to a ‘grave danger,’” and COVID today clearly qualifies.
The ‘grave danger’ standard permits OSHA to issue regulations on facemasks, distancing, record-keeping, and more. But especially relevant is a rule on ventilation. It states:
Improving existing ventilation and ensuring optimal performance of ventilation is an effective way to reduce viral transmission in occupational populations. Work sites with existing heating, ventilation, and air conditioning (HVAC) systems can utilize improvements to, and maintenance of, high performance ventilation as part of a layered response for infectious disease control.
So far, so good. Ventilation, through HVAC systems, replaces indoor air with outdoor air, and outdoor air is cleaner and safer, thanks to the oxidation that naturally occurs through sunshine. But ventilation alone is not enough, as OSHA recognizes. The Interim Final Rule recommends that ventilation be “complemented by other measures.” Specifically, the regulations require….
.…employers who own or control buildings or structures with an existing heating, ventilation, and air conditioning (HVAC) system(s) must ensure that…all filters are rated Minimum Efficiency Reporting Value (MERV) 13 or higher, if compatible with the HVAC system(s). If MERV-13 or higher filters are not compatible with the HVAC system(s), employers must use filters with highest compatible filtering efficiency for the HVAC system(s). 1910.502(k)(1)(iii).
Problems of Ventilation Plus Filtration
OSHA recognizes that HVAC systems can’t eliminate pathogens simply by exchanging air. The solution, says the agency, is adding a MERV-13 filter. That filter, says the rule, “is at least 85-percent efficient at capturing particles from 1 µm to 2 µm in size.” (1 µm, or micron, is one-one-millionth of a meter.) But a study published in the International Journal of Environmental Research and Public Health estimates that “the minimum size of the respiratory particle that can contain SARS-CoV-2 is approximately 0.4 μm.” A MERV-13 filter captures only 66% of particles between 0.3 µm and 1 µm in size.
Filters placed on ventilation systems present other problems as well:
Also, it’s critical to understand just how much ventilation is necessary to clean interior air. Ventilation systems use a measurement called Air Changes per Hour (ACH), that is, the number of times an hour that the system brings in a volume of fresh air equal to the room volume. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommends a minimum of 0.35 ACH for homes. Schools should be designed to have 3 ACH, but most fall short of that level in practice. The CDC recommends between 6 ACH and 15 ACH for hospitals.
But an “air change” does not immediately make interior air perfectly clean and safe. As fresh air comes in, it mixes with interior air, which can be contaminated. The entire mixture becomes diluted with some proportion of contamination still present, so increasingly large amounts of new air are needed in order to remove the same amount of contaminants as earlier injections of outside air. According to the CDC’s calculations, a room served by a system generating 4 ACH will still take 104 minutes to eliminate 99.9% of the room’s initial concentration of contaminants, and, of course, during that nearly two-hour period, many contaminated people can enter the room.
A Better Way to Augment Ventilation Systems
Many healthcare facilities managers have found a better way to augment their current HVAC systems: purchase relatively low-cost units that generate submicroscopic particles that flow immediately through the air and inactivate pathogens, even on surfaces. These units can either be placed on existing HVAC systems, without causing a pressure drop, or can stand alone.
For example, the Philadelphia School District (PSD) purchased 9,500 anti-viral air-purification devices last month from ActivePure, a Dallas-based company that uses a process called advanced photocatalysis. The FDA has granted clearance to the ActivePure Medical Guardian, which uses the same technology as the company’s other devices. Says a PSD release:
Unlike conventional filtration-based air purifiers, these purifiers work immediately and do not require capture or exposure time. They work by rapidly and continuously filling a room with virus-neutralizing particles to instantly break viruses down to their component parts, eliminating them on contact.
By contrast, the OSHA regulations appear to be misguided and antiquated, ignoring solutions that are both more effective in inactivating pathogens and more cost-effective. One reason may be that they are informed by ASHRAE, a trade association influenced by large HVAC companies. For example, the president and one of the four vice presidents are both executives of Trane, the Ireland-domiciled HVAC giant with a market capitalization of $46 billion.
The ventilation industry has failed to keep people safe indoors for decades now, but it is encouraging to see more attention paid to health rather than to just heating and cooling. Still, the limitations of ventilation in maintaining health need to be recognized. Kenneth and Gary Elovitz, two Massachusetts energy economists, wrote last year in HPAC Engineering, “The primary role of HVAC systems is to maintain comfort, usually measured by temperature, humidity, and odor control in the conditioned space.” Now, because HVAC systems move air, “there is interest in whether HVAC systems can play a role in managing infectious disease transmission.” But, they write, “HVAC systems cannot be the primary means of infectious disease control.” They conclude:
No practical amount of ventilation can be relied on or expected to protect occupants over long exposure times like the 6 or 8 hours people might spend together in an office or school classroom. Similarly, ventilation is unlikely to succeed as the prime means of protection for people in close contact in a small space like a private office.
Creating Outdoor Air Inside
Rather than a requirement that will lead to increasing the power of existing HVAC systems and attaching a filter, OSHA could allow an exemption for healthcare facilities that deploy modern technologies, such as advanced photocatalysis, an updated and improved version of photocatalytic oxidation, or PCO. As Fei He of Pohang University of Science and Technology in South Korea wrote recently in the journal Nature:
PCO is proposed as an ideal technology for air purification because it can degrade diverse air pollutants into non-toxic or less harmful forms using solar (or artificial) light under ambient conditions. The photocatalyst (PC) process has some intrinsic similarity to the self-cleaning mechanism in Earth’s atmosphere in that both are based on indirect (sensitized) photooxidation to generate in situ oxidants in air.
Rather than bringing outdoor air inside through a mechanism that consumes large amounts of energy, PCO recreates indoors the organic process that continuously occurs in outdoor air to cleanse the atmosphere. Each breath of outdoor air contains billions of oxidative particles, which are the atmosphere’s primary self-cleaning mechanism. These particles continuously break down pollutants. But without sunlight indoors, cleansing particles are normally missing from interior environments.
Advanced photocatalytic technology restores the naturally occurring oxidizer particles to levels that will inactivate pathogens. The technology improves on simple PCO with a proprietary reactor that speeds up the process and avoids the generation of ozone and volatile organic compounds that have plagued earlier versions of PCO.
The Missing Data on Delta
“Where the hell are the data?” said the headline on an Aug. 9 Axios report, which continued, “Biden administration officials are growing frustrated with the lack of internal visibility into data being collected by the CDC, particularly as they try to deal with Delta’s spread.”
It's true that U.S.-based research on the new variant is limited. But the study we referred to above, by Jamie Lopez Bernal of Public Health England, et al., published in the NEJM, does examine the effectiveness of vaccines against Delta in the United Kingdom. The Pfizer-BioNTech vaccine, administered in two doses, was 88% effective in preventing infection by Delta; the Astra Zeneca vaccine was 67% effective. This U.K. study did not test Moderna.
A new Mayo Clinic study, not yet published in a peer-reviewed journal but released as a pre-print on Aug. 6, had findings regarding the Pfizer vaccine that were at odds with the U.K. research. Both the Moderna and Pfizer vaccines were “highly effective” in earlier research by Mayo, with Moderna 86% effective against infection and 92% effective against hospitalization and Pfizer in the same range. But in July, with Delta rampant (a prevalence of 70%), Moderna’s effectiveness against infection fell to 76% and Pfizer’s to 42%.
Meanwhile, a South African study, taken during high Delta prevalence, found that the J&J vaccine, which was administered to 477,000 health care workers in the country, was 91% to 96% effective in preventing death and 71% effective in preventing hospitalization.
In a separate study, also published Aug. 6 in MMWR, researchers found that among “Kentucky residents who were previously infected with SARS-CoV-2 in 2020, those who were unvaccinated against COVID-19 had significantly higher likelihood of reinfection during May and June 2021,” when Delta was becoming widespread. If you had COVID before and did not get a vaccination, you were 2.3 times more likely to get COVID again, compared with those who were vaccinated.
The Kentucky study follows this report on July 14 in JAMA:
After an infection with SARS-CoV-2, most people—even those with mild infections—appear to have some protection against the virus for at least a year, a recent follow-up study of recovered patients published in Nature suggests. What’s more, this and other research demonstrates that vaccinating these individuals substantially enhances their immune response and confers strong resistance against variants of concern, including the B.1.617.2 (delta) variant.
The Dreaded Third Tier
Vaccines appear to be doing a good job battling the Delta variant, but, with unvaccinated people providing a breeding ground, the virus can be expected to continue to mutate. The U.S. Government has developed a three-tiered classification system for variants, and, so far, no COVID-19 variant is in the top tier, “variants of high consequence.” Such a variant, says an American Chemical Society website, “is defined by failure to be detected by diagnostics, significantly reduced susceptibility to vaccines or other therapies, and more severe clinical disease (i.e., increased hospitalizations) above the levels described for the lower tiers.”
The second tier, called “variants of concern” and home to the original SARS-CoV-2 virus discovered in Wuhan and the Delta variant, is bad enough, but, as we have seen, it is highly susceptible to vaccines. A mutation could, however, produce a variant that qualifies for the third tier. The good news is that the proper tools to fight interior spread should be able to inactivate any new variant as quickly and easily as they can the current COVID-19 virus and other pathogens, which, by the way, tend to be even more difficult to tackle than an enveloped RNA virus like SARS-CoV-2.
COVID Solutions Bulletin
Our mission is to educate people on innovative solutions to the COVID-19 crisis in America. We need to get back to work, to school, to play – to enjoying life. We can’t get there without thwarting the current pandemic and preparing for the possibility of other pathogens to come.
COVID Solutions Bulletin is a publication providing regular updates on new and existing technologies that can help stop the spread of COVID-19, and help clear the air to open America back up.