Impacts of the COVID-19 pandemic on the infection prevention and control field: Findings from focus groups conducted with association for professionals in infection control & epidemiology (APIC) members in fall 2021

INTRODUCTION

Emergence of the Delta variant in 2021 changed the pandemic landscape and led to healthcare surges across the US, despite availability of COVID-19 vaccine. Anecdotal information indicated that the infection prevention and control (IPC) field was changing, but formal assessment was needed.

METHODS

Focus groups (6) were conducted with APIC members in November and December, 2021 to elicit infection preventionists' (IP) opinions changes to the IPC field due to the pandemic. Focus groups were audio recorded via Zoom and transcribed. Content analysis was used to identify major themes.

RESULTS

Ninety IPs participated. IPs described multiple changes to the IPC field during the pandemic, including being more involved in policy development, the challenge of transitioning back to routine IPC while still responding to COVID-19, increased need for IPs across practice settings, difficulties in recruiting and retaining IPs, presenteeism in healthcare, and extensive burnout. Participants suggested approaches to improve IPs' wellbeing.

CONCLUSIONS

The ongoing pandemic has brought significant changes to the IPC field, including a shortage of IPs just as the field is expanding rapidly. The continued overwhelming workload and stress due to the pandemic has resulted in burnout among IPs and the need for initiatives to improve their wellbeing.

Two statistical regimes in the transition to filamentation

We experimentally investigate fluctuations in the spectrum of ultrashort laser pulses propagating in air, close to the critical power for filamentation. Increasing the laser peak power broadens the spectrum while the beam approaches the filamentation regime. We identify two regimes for this transition: In the center of the spectrum, the output spectral intensity increases continuously. In contrast, on the edges of the spectrum the transition implies a bimodal probability distribution function for intermediate incident pulse energies, where a high-intensity mode appears and grows at the expense of the original low-intensity mode. We argue that this dual behavior prevents the definition of a univoquial threshold for filamentation, shedding a new light on the long-standing lack of explicit definition of the boundary of the filamentation regime.

Infection preventionists' experiences during the second year of the COVID-19 pandemic: Findings from focus groups conducted with association for professionals in infection control & epidemiology (APIC) members

INTRODUCTION

COVID-19 epidemiology changed dramatically in spring 2021 when vaccine became widely available and the Delta variant emerged. There was a need to identify current infection prevention challenges due to changing pandemic epidemiology.

METHODS

Six focus groups were conducted via Zoom with APIC members in November and December, 2021 to elicit infection preventionists' (IP) experiences with the COVID-19 pandemic after the Delta variant had emerged. Each focus group was audio recorded then transcribed verbatim. Content analysis was used to identify major themes.

RESULTS

In total, 90 IPs participated (average of 15 IPs per focus group). Participating IPs described multiple issues they have faced during the second year of the COVID-19 pandemic after the Delta variant emerged, including continuing challenges with personal protective equipment, changes in pandemic restrictions that caused confusion and pushback, the hope when vaccine first became available and then despair when there was more vaccine breakthrough than anticipated, staffing and medical supply shortages, overwhelming workloads, and anger towards health care personnel and IPs. However, IPs felt more valued by leadership, and reported greater internal collaboration and external coordination of care.

CONCLUSIONS

The second year of the pandemic brought ongoing and new challenges for IPs, but also better coordination of care. Strategic initiatives are needed to address the identified challenges, such as how to prioritize tasks when IPs are overwhelmed.

Assessing classroom and laboratory spread of COVID-19 in a university after elimination of physical distancing

The objective of this study was to assess COVID-19 classroom transmission in the university setting when physical distancing was eliminated. Data was collected in fall 2021 at a private university. Universal masking, robust contact tracing, vaccination requirement, and enforced testing were in place. Exposures were classified as classroom versus non-classroom. ANOVA and chi-squared tests were used to identify significant relationships between predictors and COVID-19 test result. Logistic regression was conducted to investigate the relationship between exposure type and test result. A total of 162 student cases were identified with 1,658 associated close contacts. One-third of contacts (31.1%, n = 516) only had a non-classroom exposure, 63.8% (n = 1,057) only had a classroom exposure, and 5.1% (n = 85) had both. Close contacts were significantly more likely to test positive if they had a non-classroom exposure (60 of 601; 10.0%) compared to a classroom exposure (1 of 1057; 0.1%) (OR 58.8, CI 18.5-333.3, p < 0.001). Removing physical distancing in classrooms that had universal masking did not result in high rates of COVID-19 transmission. This has policy implications because eliminating physical distancing does not greatly increase transmission risk when universal masking is in place.

Modifications to student quarantine policies in K-12 schools implementing multiple COVID-19 prevention strategies restores in-person education without increasing SARS-CoV-2 transmission risk, January-March 2021

OBJECTIVE

To determine whether modified K-12 student quarantine policies that allow some students to continue in-person education during their quarantine period increase schoolwide SARS-CoV-2 transmission risk following the increase in cases in winter 2020-2021.

METHODS

We conducted a prospective cohort study of COVID-19 cases and close contacts among students and staff (n = 65,621) in 103 Missouri public schools. Participants were offered free, saliva-based RT-PCR testing. The projected number of school-based transmission events among untested close contacts was extrapolated from the percentage of events detected among tested asymptomatic close contacts and summed with the number of detected events for a projected total. An adjusted Cox regression model compared hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy.

RESULTS

From January-March 2021, a projected 23 (1%) school-based transmission events occurred among 1,636 school close contacts. There was no difference in the adjusted hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy (hazard ratio = 1.00; 95% confidence interval: 0.97-1.03).

DISCUSSION

School-based SARS-CoV-2 transmission was rare in 103 K-12 schools implementing multiple COVID-19 prevention strategies. Modified student quarantine policies were not associated with increased school incidence of COVID-19. Modifications to student quarantine policies may be a useful strategy for K-12 schools to safely reduce disruptions to in-person education during times of increased COVID-19 community incidence.

SARS-CoV-2 Transmission to Masked and Unmasked Close Contacts of University Students with COVID-19 - St. Louis, Missouri, January-May 2021

Universities open for in-person instruction during the 2020-21 academic year implemented a range of prevention strategies to limit the transmission of SARS-CoV-2, the virus that causes COVID-19, including physical distancing, mask use, vaccination, contact tracing, case investigation, and quarantine protocols (1). However, in some academic programs, such as health-related programs, aviation, and kindergarten through grade 12 (K-12) education, maintaining physical distance while still providing instruction is difficult; for universities with such programs, a single confirmed case of COVID-19 could result in a large number of students, staff members, and instructors being designated close contacts and requiring quarantine if they are not fully vaccinated, even if masks were worn when contact occurred. In January 2021, the St. Louis City Health Department allowed Saint Louis University (SLU) to implement a modified quarantine protocol that considered mask use when determining which close contacts required quarantine.* To assess the impact of the protocol, SLU assessed positive SARS-CoV-2 test result rates by masking status of the persons with COVID-19 and their close contacts. During January-May 2021, 265 students received a positive SARS-CoV-2 test result; these students named 378 close contacts. Compared with close contacts whose exposure only occurred when both persons were masked (7.7%), close contacts with any unmasked exposure (32.4%) had higher adjusted odds ratios (aORs) of receiving a positive SARS-CoV-2 test result (aOR = 4.9; 95% confidence interval [CI] = 1.4-31.1). Any additional exposures were associated with a 40.0% increase in odds of a positive test result (aOR = 1.4; 95% CI = 1.2-1.6). These findings reinforce that universal masking and having fewer encounters in close contact with persons with COVID-19 prevents the spread of SARS-CoV-2 in a university setting. Universities opening for in-person instruction could consider taking mask use into account when determining which unvaccinated close contacts require quarantine if enforced testing protocols are in place. However, this study was conducted before the B.1.617.2 (Delta) variant became the dominant strain of SARS-CoV-2 in the United States, which could have affected these findings given that the Delta variant has been found to be associated with increased transmissibility compared to previous variants.

Testing Critical Slowing Down as a Bifurcation Indicator in a Low-Dissipation Dynamical System

We study a two-dimensional low-dissipation nonautonomous dynamical system, with a control parameter that is swept linearly in time across a transcritical bifurcation. We investigate the relaxation time of a perturbation applied to a variable of the system and we show that critical slowing down may occur at a parameter value well above the bifurcation point. We test experimentally the occurrence of critical slowing down by applying a perturbation to the accessible control parameter and we find that this perturbation leaves the system behavior unaltered, thus providing no useful information on the occurrence of critical slowing down. The theoretical analysis reveals the reasons why these tests fail in predicting an incoming bifurcation.