HPIO is collecting the latest research so that Ohio policymakers and other stakeholders can make informed decisions on the rapidly evolving COVID-19 pandemic. Regular research updates are mailed to HPIO’s email contact list (click here to join our mailing list and if you are already signed up for our mailing list and do not see the updates, please check your spam folder).
SARS-CoV-2 transmission in offices and poorly ventilated spaces
includes suggestions of ways to increase the distance between employees and to disinfect workspaces. Notably, the CDC recommends that employees wear a cloth face covering in all areas of the business. This guidance could be useful for Ohio office-based employers who are making decisions regarding employees’ primary places of work. The guidance also includes links to other sources of information on suggested ventilation and water safety protocols.
A commentary on the spread of COVID-19 through droplets (The Lancet Respiratory Medicine, May 27) studied the rate at which large and small droplets from speaking, breathing and coughing fall to the ground after being expelled. Large droplets tended to fall to the ground quickly and do not travel far before doing so. Small droplets tended to linger in the air for about 9 minutes before reaching the ground. Furthermore, they examine how types of ventilation affect the rate at which potentially viral-laden droplets can be removed from a room. The best ventilation reduced the number of droplets in the room by half after 30 seconds, the second-best reduced droplets by half in one to four minutes, and no ventilation took five minutes to reduce droplets by half.
These results could be useful when designing COVID-19 response policies for poorly ventilated spaces, like public transport and nursing homes, which have been reported as sites of viral transmission despite preventive physical distancing. The authors recommend that public health officials advocate for the avoidance of poorly ventilated spaces and improved ventilation to reduce potentially infectious aerosols.
Effectiveness of stay-at-home orders
A study of state-level stay-at-home orders on COVID-19 (American Journal of Infection Control, May 24) found that infection rates dropped after state orders were put in place. Infection rates were 0.113/day pre-order and 0.047/day post-order. The results were consistent across states and support the usefulness of stay-at-home orders in reducing COVID-19 infection rates. Before the stay-at-home order, Ohio’s infection rate was 0.15 per day. After the order was put in place, the infection rate dropped to 0.053 per day.
Municipal sewage testing as a COVID-19 outbreak indicator
A study on the effectiveness of testing waste water to determine prevalence of COVID-19 (Yale University and Connecticut Agricultural Experimental Station [published pre-print by MedRxIV], May 22) found that sampling sewage is a potential way for states to detect and study potential trends in cases of COVID-19 earlier than currently possible from indicators such as local hospital admissions and compiled COVID-19 testing data. The study examined SARS-CoV-2 RNA concentration in the primary sewage sludge of a northeastern United States metropolitan area (New Haven, Connecticut) amid the Spring 2020 outbreak of COVID-19. All environmental samples collected and included in the study contained SARS-CoV-2 RNA and showed a high correlation with the COVID-19 epidemiological curve as well as with local hospital admissions. The concentration of SARS-CoV-2 RNA in the primary sewage sludge samples was subsequently identified as a seven-day leading indicator ahead of COVID-19 testing data and predated local hospital admissions data by three days.
SARS-CoV-2 screening in long-term care settings
A study of COVID-19 spread in assisted and independent living (JAMA, May 21) found that early universal surveillance to identify asymptomatic infections, coupled with prevention strategies, can reduce the likelihood of a widespread outbreak. The study involved universal testing of 80 residents in assisted living and independent living communities twice, with the second screening seven days after the first. A symptom questionnaire was also completed by residents and staff. Staff were tested once. SARS-CoV-2 was detected in three residents (3.8%), with none of them feeling ill and one reporting that he had recently had a cough and loose stool. Two of 62 staff (3.2%) tested positive for the virus, both having symptoms. One new resident infection was found during the second round of viral testing. This resident was not experiencing symptoms. All four residents who tested positive remained asymptomatic throughout the next 14 days, highlighting the challenge of controlling infection spread using symptom screening alone. Social isolation and infection prevention protocols were implemented at the site throughout the time of the study. A widespread outbreak was avoided. Two residents were hospitalized with COVID-19 prior to the study, with the study beginning rapidly after these hospitalizations.
A study of SARS-CoV-2 infection at a skilled nursing facility for veterans (CDC MMWR, May 22) found that universal and repeated testing of both residents and staff, along with isolation and cohorting of residents who test positive for COVID-19, were effective strategies for preventing infection at this skilled nursing facility. All 99 residents at the facility were tested and a total of 19 cases were diagnosed (19.2%). Fourteen of the 19 cases were asymptomatic and eight of the 14 later developed symptoms. Of 136 staff, eight were found to have COVID-19 with half of those being asymptomatic. Testing of all residents was repeated weekly until all residents had negative test results. One resident died with COVID-19. “Swift isolation and cohorting of residents with COVID-19 reduced further transmission within the SNF; residents who had positive test results were quickly transferred out of the SNF, either to the acute care hospital or directly to a separate COVID-19 recovery unit.”
Superspreading during mass gatherings
A study describing a COVID-19 outbreak in Jordan that began after a wedding (CDC Emerging Infectious Diseases, May 20) demonstrates the high communicability of COVID-19 and the significant risk for SARS-CoV-2 virus transmission during mass gatherings. Of 350 wedding attendees, 76 developed COVID-19, an attack rate of 22%. Authors noted a high rate (47.4%) of asymptomatic carriers among those infected. Before the outbreak from this wedding, only one case, which was imported, had been reported in Jordan in early March. By April 10, the number of confirmed cases from the wedding constituted 24% of all COVID-19 cases in Jordan.
Risk stratification for workers
A report on standards for returning to work (NEJM, May 26) proposes a framework to help clinicians counsel patients about continuing to work in the midst of the pandemic that is based on their occupational risk of contracting SARS-CoV-2 and their risk of death if they are infected. This framework is displayed in a matrix that stratifies individual risk based on occupational and personal factors. Persons with high occupational risk of contracting COVID-19 and/or high personal risk of death from COVID-19 should consider stopping work and discuss risk with their clinician.
Pandemic response in correctional and detention facilities
A study of COVID-19 in the Louisiana prison system (MMWR, May 8) found that physical, logistical and security constraints inherent to correctional facilities make it difficult to fully implement public health recommendations related to the pandemic. The reported inability of some facilities to individually quarantine close contacts of incarcerated or detained persons with COVID-19 could result in spread among persons within the quarantine units. A COVID-19 Management Assessment and Response (CMAR) tool could be used to assess COVID-19 management practices and guide strategies to address gaps. Response to COVID-19 in correctional and detention facilities should account for the inherent limitations these facilities face in acting upon public health guidance.
A World Health Organization document providing guidance to assist correctional and detention facilities in developing a response to the COVID-19 (WHO, March 15) outbreak highlights that people in prisons and other places of detention are likely to be more vulnerable to the COVID-19 outbreak than the general population because of the confined conditions in which they live together for prolonged periods of time. Moreover, experience shows that prisons, jails and similar settings where people are gathered in close proximity may act as a source of infection, amplification and spread of infectious diseases within and beyond prisons. Controlling the spread of COVID-19 infection in prisons and other places of detention is essential to protecting the health of all those who live and work in them and those who visit them and protecting the outside community. The WHO also created a companion checklist for use by policymakers and prison administrators to evaluate their level of preparedness to prevent and control COVID-19 in prisons and other places of detention.
Pediatric condition potentially associated with SARS-CoV-2
A study of a cluster of eight children with hyperinflammatory shock (The Lancet, May 7) suggests that a new phenomenon affecting previously asymptomatic children with SARS-CoV-2 infection manifesting as a hyperinflammatory syndrome with multiorgan involvement similar to Kawasaki disease shock syndrome. The multifaceted nature of the disease course underlines the need for multispecialty input (intensive care, cardiology, infectious diseases, immunology, and rheumatology). Clinical presentations were similar, with unrelenting fever, variable rash, conjunctivitis, peripheral edema, and generalized extremity pain with significant gastrointestinal symptoms. All children initially tested negative for SARS-CoV-2 on broncho-alveolar lavage or nasopharyngeal aspirates. Since discharge, two of the children tested positive for SARS-CoV-2.
An alert from the New York City Health department (NYC Health, May 4) notified pediatric providers of 15 cases of a pediatric multi-system inflammatory syndrome similar to cases reported in the U.K. Among the 15 cases identified in New York, 4 tested positive for SARS-CoV-2 by PCR testing, 6 tested negative by PCR and positive by serology and 5 were negative. The alert provides instructions for providers to refer potential cases to appropriate specialists and the NYC Health Department.
Evidence of presymptomatic and asymptomatic spread
A literature review of the most recent epidemiologic, virologic and modeling evidence (CDC Emerging Infectious Diseases, May 4) found support for possible transmission of SARS-CoV-2, the virus that causes COVID-19, from people who are presymptomatic or asymptomatic. SARS-CoV-2 transmission in the absence of symptoms reinforces the value of measures that prevent the spread of SARS-CoV-2 by infected persons who may not exhibit illness despite being infectious.
Mobility and virus transmission
A modeling study uses death and mobility data from several regions in northern Italy (Imperial College, May 4) found that, in the absence of additional interventions, even a 20% return to pre-lockdown mobility could lead to a resurgence in the number of deaths far greater than experienced in the current wave in several regions. The study estimates the impact on mortality of three post-lockdown scenarios over the next eight weeks: (1) mobility remains the same as during the lockdown, (2) mobility returns to pre-lockdown levels by 20% and (3) mobility returns to pre-lockdown levels by 40%. The mobility data was provided by Google and serves as a proxy for behavior change caused by non-pharmaceutical interventions, including change in visits to locations such as grocery stores, parks, transit stations, retail and workplaces. Because increases in the number of hospitalizations and deaths lag behind increases in transmission intensity, the control of a future potential resurgence in transmission relies on the early identification and isolation of infections and on the timely suppression of local clusters of infection.
A study of cell phone data at various types of businesses (MIT, April 26) found that “banks, general merchandise stores, dentists, grocery stores and colleges should face relatively loose restrictions and gyms, sporting goods stores, liquor stores, tobacco stores and cafes should face relatively tight restrictions.” The study uses Safegraph data from cell phones, as well as measures related to 30 categories of businesses, to inform re-opening policies. The findings can inform re-opening policies and, if necessary, future closure policies.
A study of the spread of COVID-19 using cell phone data (NBER, April 1) found that small businesses should be permitted to re-open first, as these are generally less dense environments. A caveat is that these businesses would have to be as good as larger businesses at public health practices (i.e. wearing masks, no-touch doors). It is important to note that, since the study only looks at mobile tracking data, it does not include what people were doing in these stores (i.e. shopping, working).
Workplace reopening and safety guidance
A CDC report on factors contributing to the spread of COVID-19 in meatpacking and poultry processing plants (CDC MMWR early release, May 1) includes data on 115 facilities with 130,000 workers in19 states, including Ohio. There have been 4,913 cases confirmed and 20 deaths in meat processing facilities. Lack of physical distancing and cleanliness are cited as contributors to spread, in addition to multigenerational and dense living situations and language barriers in some facilities. Recommendations include improving distancing to the extent possible, engineering approaches (such as not having fans blowing across workers), encouraging cloth masks (if cleaned regularly and with appropriate donning and doffing) and handwashing, disinfecting surfaces and providing paid medical leave for workers who are ill. Training should be provided by culturally competent trainers in the language spoken by workers. Data for Ohio indicated 10 cases in 1 pork plant with 710 workers. No deaths were reported.
A new CDC framework for cleaning and disinfection practices in public spaces, workplaces, schools and homes (CDC, April 28) highlights that reopening public spaces will require careful planning and emphasizes the importance of reducing the risk of exposure to COVID-19 by cleaning and disinfection. The framework states that normal routine cleaning with soap and water will decrease how much of the virus is on surfaces and objects. The authors also state that disinfection using EPA-approved disinfectants against COVID-19 can also help reduce the risk. The EPA has compiled a list of disinfectant products that can be used against COVID-19, available on the EPA website. When EPA-approved disinfectants are not available, alternative disinfectants can be used (e.g. 1/3 cup of bleach added to 1 gallon of water, or 70% alcohol solutions).
Contact tracing and isolation strategies
An epidemiological study of COVID-19 (The Lancet Infectious Diseases, April 27) found that the attack rate of the virus does not differ significantly by age, with on average 7% of close contacts becoming infected, around 80% of these contacts showing symptoms and 3% of infections manifesting severe disease at initial assessment. They also found that contact-based surveillance and isolation in Shenzhen, China reduced the duration an infected individual transmits in the community by 2 days. The household secondary attack rate was 11.2%, and children were as likely to be infected as adults. The observed reproductive number (R) was 0.4, with a mean serial interval of 6.3 days. The authors found that because children were at a similar risk of infection to the general population, they should be considered in analyses of transmission and control. The analysis presents one of the first estimates of the serial interval, secondary household attack rate and dispersion for SARS-CoV-2, the virus that causes COVID-19, based on active surveillance data.
A comparison of institution-based and home-based isolation for COVID-19 (The Lancet, April 29) found that institution-based isolation, modeled after China, reduced contact rates by 75% in the household and by 90% in the community. The authors estimated that home-based isolation, modeled after Europe and the U.S., caused a 50% reduction in contact within the home and a 75% reduction in contact in the community. The authors of the study suggest that policymakers facing overburdened health-care facilities to consider strategies to reduce transmission, such as repurposing hotels or dormitories.
A study of isolation and tracing strategies found that, in most scenarios, highly effective contact tracing and case isolation are enough to control a new outbreak of COVID-19 within 3 months. The probability of control decreases, however, with long delays from symptom onset to isolation, fewer cases ascertained by contact tracing and increasing transmission before symptoms.
An article on immunology and COVID-19 (The Lancet, April 27) states that most of the available COVID-19 serology data derive from people who have been hospitalized with severe infection. In this group, around 90% develop antibodies within the first 2 weeks of symptomatic infection. However, a key question concerns antibodies in non-hospitalized individuals who either have milder disease or no symptoms. Anecdotal results from community samples have found that less than 10% of those tested developed specific antibodies. In the absence of larger seroprevalence datasets, it seems likely that natural exposure during this pandemic might, in the short to medium term, not deliver the required level of herd immunity and there will be a substantial need for mass vaccination programs.
Mitigating the spread of COVID-19 in healthcare settings
A simulation study of the effectiveness personal protective equipment for emergency physicians and nurses (JAMA Research Letter, April 27) found that, despite the use of PPE, fluorescent markers were found on the uncovered skin, hair and shoes of participants after simulations of the emergency department management of patients experiencing respiratory distress. The findings suggest that the current recommendations for personal protective equipment may not fully prevent exposures in emergency department settings. Clothing that covers all skin may further diminish exposure risk.
A study investigated the aerodynamic nature of SARS-CoV-2 (Nature, April 27) found that the concentration of COVID-19 virus in aerosols detected in isolation wards and ventilated patient rooms in two hospitals in Wuhan, China was very low, but it was elevated in patient bathrooms. Levels of airborne SARS-CoV-2 RNA in the majority of public areas was undetectable, except in two areas prone to crowding, possibly due to infected carriers in the crowd. Authors found that some medical staff areas initially had high concentrations of viral RNA, but these levels were reduced to undetectable levels after implementation of rigorous sanitization procedures. To reduce the concentration of SARS-CoV-2 aerosol in medical staff areas, hospitals can implement more rigorous and thorough sanitization measures, including more frequent spraying of chlorinated disinfectant on the floor of patient areas, spraying alcohol disinfectant all over the protective apparel before taking off and prolonged operation time of indoor air purifiers. Results also indicate that room ventilation, open space and proper use and disinfection of bathrooms can effectively limit the concentration of SARS-CoV-2 RNA in aerosols.
Aerosol transmission of COVID-19 and the role of face masks
COVID-19 transmission dynamics in California, Washington
Intermittent social distancing may be needed long term
A modeling study based on other coronaviruses (Science, April 14) projects that recurrent wintertime outbreaks of SARS-CoV-2, the virus that causes COVID-19, will probably occur after the initial, most severe pandemic wave. The authors conclude that intermittent social distancing could prevent critical care capacity from being exceeded, but that widespread surveillance will be required to time the distancing measures correctly. Periodic social distancing will likely need to continue through 2022 or beyond in order to avoid overwhelming the healthcare system. The findings mean that Ohio policymakers should be prepared to implement intermittent social distancing over the long-term to handle possible seasonal peaks that could strain the critical care system. Effective timing of changes in social distancing should be informed by widespread surveillance, indicating that increased testing capacity (including serological testing) is critical for informing policy decisions. Once data are available, benchmarks could be established to guide timing of increased and decreased social distancing policies.
COVID-19 virus found on shoes, office equipment of hospital workers
Plan lays out steps needed before easing social distancing
Assessment outlines lessons learned from China’s relaxing of social distancing restrictions
Studies shed light on impact of COVID-19 school closures
Tactics outlined for increasing public health capacity to address COVID-19 pandemic
Study finds link between air pollution, COVID-19 death rate
Mitigating COVID-19 spread in correctional facilities
Studies examine how long the COVID-19 virus lives
Study of 1918 flu pandemic finds that social distancing can help economy in long run
Lessons learned from Seattle and New York
In an audio interview (NEJM, April 1, 2020), editors of the New England Journal of Medicine share lessons learned from New York City and Seattle. They discuss New York as an example of a city with widespread community transmission and Seattle as an example of how infections among vulnerable populations increase demand on the healthcare system. Highlights from the interview include:
- To flatten the curve on hospital demand, focus on reducing the spread of infection in healthcare facilities and other environments with highly vulnerable populations
- Maintain social distancing efforts while working toward faster and more widespread testing and building healthcare capacity
- Policy action may be needed to address healthcare worker shortage