Updates on the emerging novel coronavirus pandemic from the Johns Hopkins Center for Health Security.

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EPI UPDATE The WHO COVID-19 Dashboard reports 23.75 million cases (210,183 new) and 815,038 deaths (4,588 new) as of 9:30am EDT on August 26. The global daily incidence appears as though it may have passed a peak and is now beginning to exhibit a slow decline. 

The US CDC reported 5.72 million total cases (33,076 new) and 176,617 deaths (394 new). In total, 19 states (no change) are reporting more than 100,000 cases, including California with more than 600,000 cases; Florida and Texas with more than 500,000; New York with more than 400,000; and Georgia and Illinois with more than 200,000. The US represents approximately 24% of the total global COVID-19 incidence and 22% of the total global deaths, despite accounting for only 4% of the global population.

Several US territories continue to exhibit extremely high per capita daily incidence. Guam is reporting 326 new daily cases per million population, which would be #1 globally. It previously appeared as though much of Guam’s increased incidence was due to a large spike of 105 new cases reported on August 21; however, Guam has reported more than 50 new cases on 4 of the 5 days since then. The US Virgin Islands is reporting 320 daily cases per million population, which would also be #1 globally. Puerto Rico’s daily incidence has decreased over the past week or two, but it is still reporting 150 daily cases per million population, which would put it at #8 globally, falling between Israel and the Bahamas.

As we have covered previously, the US passed its second COVID-19 peak in late July, and we have been closely monitoring for an associated decrease in mortality. Now, approximately 1 month after the peak daily incidence, the US seems to be exhibiting the start of a decline in mortality. A large spike in deaths reported around August 6 makes it a little difficult to identify the beginning of the decline; however, the daily mortality has been slowly decreasing for at least the past week, dipping below 1,000 new deaths per day for the first time since July 27. Additionally, COVID-19 mortality in the South, Southwest, and West regions—the most severely affected regions during the US resurgence over the past several months—appear to have passed their respective peaks as well. Mortality in these regions remains elevated, but it is at least starting to trend downward. Notably, COVID-19 mortality is slowly increasing in the Midwest region, where we have also observed increasing and elevated incidence since mid-June. The Midwest is a mix of states that were severely affected early in the US epidemic, such as Illinois and Michigan; those that recently peaked as part of the summer resurgence, like Ohio and Wisconsin; and those that have not yet passed their peak, including Indiana, Iowa, and Kansas.

The Johns Hopkins CSSE dashboard reported 5.79 million US cases and 178,819 deaths as of 12:30pm EDT on August 26.

US CDC TESTING GUIDANCE Earlier this week, the US CDC published a major update to its SARS-CoV-2 testing guidance. The biggest change addresses asymptomatic individuals with known exposure to a COVID-19 case. In the previous version of the testing guidance, the CDC recommended diagnostic testing for, among others, “asymptomatic individuals with recent known or suspected exposure to SARS-CoV-2 [in order to] to control transmission.” In the current iteration, the CDC states that asymptomatic individuals who have close contact with a COVID-19 case “do not necessarily need a test unless [they] are a vulnerable individual” or if it is recommended or required by their healthcare provider or local or state public health agency. Notably, testing guidance published on other sections of the CDC website, updated on the same date as the testing guidance described above, continues to include close contact with a known case as a principal consideration for testing, along with exhibiting COVID-19 symptoms and referral by healthcare providers or public health officials.

The recommendation that asymptomatic individuals with known exposure do not necessarily need to be tested has potentially serious implications for both COVID-19 control and surveillance. The updated guidance does recommend that these individuals monitor for symptoms, but as we have covered previously, it is widely understood that individuals infected with SARS-CoV-2 can transmit the infection without exhibiting symptoms—either in the days prior to the onset of symptoms or without developing symptoms at all. In fact, the CDC’s own “current best estimate” indicates that 50% of SARS-CoV-2 transmission occurs prior to the onset of symptoms (presymptomatic transmission) and that asymptomatic individuals are still 75% as infectious as symptomatic cases. Further down in the new testing guidance, at the bottom of the page, the CDC explicitly notes that infected individuals can spread the virus to others while they are not symptomatic, but the guidance does not provide further information regarding self-quarantine or other measures to mitigate this risk. Without testing, asymptomatic individuals would have no way of knowing that they are infected and potentially placing others at risk. Considering the significant role of asymptomatic and presymptomatic transmission, it is unclear why the testing guidance would de-emphasize testing any individuals with known exposure.

The new testing guidance also states that asymptomatic individuals with known exposure “should strictly adhere to CDC mitigation protocols”; however, it is not clear exactly to which protocols the guidance is referring. The CDC guidance on community-related exposures recommends that exposed individuals self-quarantine for 14 days, monitor for fever and other symptoms, and avoid higher-risk individuals, but there is no link to this information from the new testing guidance. It is possible that the CDC wholly shifted its focus to self-quarantine following all known exposures, at least for asymptomatic individuals, rather than waiting for or relying on diagnostic test results; however, this is not all that clear from reading the updated testing guidance alone. Individuals seeking information on testing would also need to know where else to look in order to get the full set of recommendations.

Regardless of whether quarantine without testing would be sufficient to contain the spread of COVID-19—including whether exposed individuals would voluntarily self-quarantine in the absence of both symptoms and a positive test—the change could also impact public health COVID-19 surveillance. The CDC guidance notes that state and local health departments may require testing for asymptomatic individuals with known exposure, but the change in guidance could have a substantial impact on the volume of testing conducted for these individuals, particularly for those not already known to health officials (eg, through contact tracing). A spokesperson for the Department of Health and Human Services argued that the updated guidance functions to support public health surveillance at the state and local levels. Public health officials have struggled since the onset of the pandemic to characterize the scale of infection in their communities, particularly with respect to asymptomatic infections or mild cases. If asymptomatic individuals with known exposure are no longer recommended for testing, this could limit the number of infections reported to public health agencies and prioritize those with more severe disease, much like what occurred early in the pandemic. This has potentially serious implications for our understanding of the level of community transmission as well as disease severity and mortality risk. Notably, the CDC guidance for schools repeatedly emphasizes the need to understand and control community transmission in order to mitigate transmission risk as students return to in-person classes. Without testing asymptomatic individuals with known exposure, it could give the false impression that community transmission is lower than it actually is, which could subsequently increase the risk for school-based transmission, clusters, and outbreaks.

CONVALESCENT PLASMA EUA Following the US FDA’s announcement of the Emergency Use Authorization (EUA) issued for the use of convalescent plasma treatment for COVID-19 patients, some experts questioned the underlying data and statements made by senior government officials—including FDA Commissioner Dr. Stephen Hahn, Secretary of Health and Human Services Dr. Alex Azar, and President Donald Trump—regarding the treatment’s efficacy. In response to the criticism, Commissioner Hahn issued a statement acknowledging that some of the data had been misrepresented. In particular, he clarified that the 35% decrease in mortality touted by President Trump, Secretary Azar, and himself referred to a relative risk reduction rather than absolute, a major issue identified by a number of health experts. He also emphasized that the FDA’s decision was based wholly on the available data and that political considerations played no role in the FDA’s determination. Notably, the clinical trial data from the Mayo Clinic study did not include a control group, so it is not actually possible to draw definitive conclusions about the treatment’s efficacy. The FDA will continue to monitor convalescent plasma data as it becomes available.

US CDC: DON’T ARGUE WITH ANTI-MASKERS Following increasing reports of violent confrontations with individuals opposed to COVID-19 social distancing policies, including mandatory mask use at some businesses, the US CDC published guidance for retail workers to manage these risks. One of their principal recommendations is not to argue with non-compliant customers if they become aggravated. Reports of threats, assault, and other violent behavior by individuals opposed to COVID-19-related policies have become more commonplace as US businesses continue to reopen and retail employees are put in the position of enforcing new store policies.

The CDC guidance remains consistent in its recommendations for mask use, social distancing, and other measures while also taking into account the heightened risk of violence for those enforcing these policies. In addition to avoiding confrontations with aggravated individuals, the guidance also recommends that employers implement threat recognition and conflict resolution training, pair workers in teams to provide support in numbers, and provide employees with a safe area to go to if threatened. The guidance seems to take a common sense stance on worker safety: it is not worth the risk of violence for employees to force individuals to comply with store policies. Regardless, it remains concerning that some individuals not only refuse to comply with recommended (or required) protective actions but will raise their opposition to the level of directly endangering the health and safety of others through physical violence. 

A Florida judge granted a temporary injunction to the state’s order requiring schools to open for in-person classes by August 31. The order was issued on July 6 by Florida’s Commissioner of Education, and it included provisions that would withhold state funding for school districts that did not comply. The judge noted that some parts of the order were unconstitutional and that Florida removed school districts' ability to choose safe reopening plans. The lawsuit, filed by the Florida Education Association (a statewide teacher’s union) and the National Association for the Advancement of Colored People (NAACP), seeks to allow local school districts to develop and implement their own reopening plans, potentially including decisions to suspend in-person classes, without risking a loss of funding. State officials indicated that they intend to appeal the judge’s ruling.

Several major colleges and universities are reporting concerning COVID-19 data shortly after resuming classes. The University of Alabama has reported more than 550 cases across its 3 universities, including the main campus in Tuscaloosa, in less than a week. Notably, this total does not include cases identified when students underwent “entry testing” prior to returning to campus. The University of North Carolina (UNC) has reported nearly 650 cases since August 10, 218 of which were reported last weekend alone. Additionally, UNC’s test positivity has increased dramatically over the past 2 weeks, jumping from 2.8% the week of August 3-9 to 32.2% the week of August 17-23, an indication that the university’s testing strategy may not be sufficient to fully capture transmission among students and staff. Currently, more than half of the available on-campus isolation and quarantine room capacity is already occupied, and the student census in on-campus residence halls has decreased by approximately 75% since August 17.

Several colleges and universities have issued warnings to students regarding gatherings that violate the schools’ COVID-19 guidelines, some of which include a variety of associated punishments for violations. Central Michigan University announced that students may be subject to fines or suspension if they attend or host large gatherings. Syracuse University is already enforcing a similar policy, reportedly suspending 23 students following a large gathering prior to the start of classes. Senior university officials described the event “incredibly reckless.” The Ohio State University also reportedly suspended more than 200 students due to large gatherings, and Penn State University reportedly suspended 2 fraternities after hosting large events. Penn State officials stated that no further disciplinary action would be taken against the students as long as they undergo SARS-CoV-2 testing.

Numerous health experts have noted problems associated with colleges and universities resuming in-person classes but blaming students for issues related to COVID-19. These policies not only aim to direct responsibility for the students’ health and wellbeing away from the school officials who are making the decisions to resume in-person classes, they also increase the risk that students will hide risky activities and avoid testing and contact tracing that would be critical to containing associated clusters and outbreaks.

MOTORCYCLE RALLY The annual Sturgis Motorcycle Rally drew hundreds of thousands of bikers from across the US to a small town in South Dakota for a 10-day festival. Health officials have identified at least 103 cases of COVID-19 across at least 8 states that are believed to be connected with the rally, and that number is expected to grow in the coming weeks. Held August 7-16, the rally drew approximately 460,000 vehicles to the small town of Sturgis, which has a population of 7,000—71 times smaller than its occupancy during the rally. Multiple reports indicate that social distancing and other protective measures, including mask use, were not widely enforced or practiced by the attendees. South Dakota health officials are conducting contact tracing operations to the extent possible, and they have already identified several exposures at the rally, including cases detected among bartenders, tattoo artists, and rally attendees.

Given the size of the event, contact tracing is a difficult task, and health officials have asked attendees to monitor their symptoms for 14 days. According to cell phone geo-location data, more than 61% of US counties have been visited by someone who attended the Sturgis Motorcycle Rally, which illustrates the potential for widespread geographic transmission of SARS-CoV-2 resulting from the event. Like other large events or gatherings, it could be several weeks before any indication of increased transmission becomes evident. And because the participants dispersed across a wide geographic area (as opposed to remaining concentrated locally), it may be very difficult to identify associated clusters or outbreaks among the broader US epidemic.

PHYSICAL DISTANCING Many national and international (eg, WHO) guidelines for social distancing and risk mitigation for COVID-19 include a minimum standard for physical distancing. For example, the prevailing guidance in the US recommends maintaining a distance of 6 feet between yourself and others, and the WHO recommends a distance of 1 meter. In reality, the risk of transmission by respiratory droplets or aerosols does not stop at this distance, but rather, they correspond to the point beyond which transmission risk is generally low. They also serve as convenient reminders to the public to maintain physical separation from others in order to mitigate transmission risk. The 6-foot or 1- or 2-meter recommendations stem from historical research on the dispersal of respiratory droplets, but they are not hard and fast rules and do not account for increased risk under a variety of conditions.

Researchers from the UK and the Massachusetts Institute of Technology (US) published an Analysis article in the journal BMJ that addresses the limitations of these recommendations and proposes an alternative method of communicating transmission risk. The authors note that respiratory droplets exist across a spectrum of sizes, with the smallest transitioning into aerosols, and these particles can travel much farther than 6 feet or 2 meters. Rather than focusing on specific distances in terms or maintaining physical distancing, they argue that guidance should account for other factors as well, including the “force of emission” (eg, breathing vs speaking vs shouting or singing), mask use, ventilation, and duration of exposure. Their proposed transmission risk framework presents the relative transmission risk for various combinations of these factors, which they argue will enable individuals to better assess their risk and take appropriate precautions, such as reducing their exposure time or increasing their physical distance from others.

While this model certainly offers a more refined and detailed risk analysis, compared to the single recommended separation distance, and more accurately captures the spectrum of risk for different environments and activities, it requires individuals to make their own risk determination and does not necessarily present the user with explicit actions to take under each scenario. In the absence of specific recommended actions, individuals may be less likely or less able to utilize the tool. Additionally, the associated precautions may vary for different environments or activities, which requires individuals to identify appropriate different precautions on their own. The concrete 6-foot or 1-meter recommendations may not sufficiently decrease transmission risk in all scenarios; however, they are simple, consistent, and easy to remember, which could increase their utility and mitigate transmission risk under a variety of scenarios, even if it is not a perfect solution. Individuals should be encouraged to consider a variety of factors in assessing their risk in any given situation, and the use of more detailed risk assessment frameworks and convenient but simplified guidance (eg, minimum recommended physical distancing) are not mutually exclusive.

SYSTEMIC RACISM & COVID-19 The Johns Hopkins Center for Health Security’s journal, Health Security, issued a call for papers for an upcoming Special Feature on systemic racism in the context of the COVID-19 pandemic. The Special Feature is scheduled to be published in May/June 2021, and all content will be open access. The COVID-19 pandemic’s myriad impacts on health, economies, and social structures have disproportionately impacted racially marginalized populations, in the US and around the world. Racial and ethnic minority communities are experiencing elevated COVID-19 morbidity and mortality, stemming in part from ineffective response efforts and longstanding barriers to accessing healthcare and public health programs and services. Evidence-based and peer-reviewed research is urgently needed to examine the root causes and impacts of systemic and pervasive racial and ethnic inequities in the context of COVID-19. This Special Feature will examine how systemic racism manifests in the practice of health security, including in preparedness for, response to, and recovery from COVID-19. Notably, the journal is actively encouraging submissions from women, underrepresented minority scholars in health security, and scholars with disabilities. Additional information is available here.