Understanding changing public transit travel patterns of urban visitors during COVID-19: A multi-stage study

COVID-19 has caused huge disruptions to urban travel and mobility. As a critical transportation mode in cities, public transit was hit hardest. In this study, we analyze public transit usage of urban visitors with a nearly two-year smart card dataset collected in Jeju, South Korea – a major tourism city in the Asia Pacific. The dataset captures transit usage behavior of millions of domestic visitors who traveled to Jeju between January 1, 2019 and September 30, 2020. By identifying a few key pandemic stages based on COVID-19 timeline, we employ ridge regression models to investigate the impact of pandemic severity on transit ridership. We then derive a set of mobility indicators – from perspectives of trip frequency, spatial diversity, and travel range – to quantify how individual visitors used the transit system during their stay in Jeju. By further employing time series decomposition, we extract the trend component for each mobility indicator to study long-term dynamics of visitors' mobility behavior. According to the regression analysis, the pandemic had a dampening effect on public transit ridership. The overall ridership was jointly affected by national and local pandemic situations. The time series decomposition result reveals a long-term decay of individual transit usage, hinting that visitors in Jeju tended to use the transit system more conservatively as the pandemic endured. The study provides critical insights into urban visitors' transit usage behavior during the pandemic and sheds light on how to restore tourism, public transit usage, and overall urban vibrancy with some policy suggestions.

Low humoral and cellular immune responses early after breakthrough infection may contribute to severe COVID-19.

Background: Little is known about the immune determinants for severe coronavirus disease 2019 (COVID-19) in individuals vaccinated against severe acute respiratory syndrome coronavirus 2. We therefore attempted to identify differences in humoral and cellular immune responses between patients with non-severe and severe breakthrough COVID-19. Methods: We prospectively enrolled hospitalized patients with breakthrough COVID-19 (severe and non-severe groups) and uninfected individuals who were vaccinated at a similar time (control group). Severe cases were defined as those who required oxygen therapy while hospitalized. Enzyme-linked immunosorbent assays and flow cytometry were used to evaluate humoral and cellular immune responses, respectively. Results: Anti-S1 IgG titers were significantly lower in the severe group than in the non-severe group within 1 week of symptom onset and higher in the non-severe group than in the control group. Compared with the control group, the cellular immune response tended to be diminished in breakthrough cases, particularly in the severe group. In multivariate analysis, advanced age and low anti-S1 IgG titer were associated with severe breakthrough COVID-19. Conclusions: Severe breakthrough COVID-19 might be attributed by low humoral and cellular immune responses early after infection. In the vaccinated population, delayed humoral and cellular immune responses may contribute to severe breakthrough COVID-19.

Short-Term Effectiveness of Oral Nirmatrelvir/Ritonavir Against the SARS-CoV-2 Omicron Variant and Culture-Positive Viral Shedding.

BACKGROUND: Information on the effectiveness of nirmatrelvir/ritonavir against the omicron is limited. The clinical response and viral kinetics to therapy in the real world need to be evaluated. METHODS: Mild to moderate coronavirus disease 2019 (COVID-19) patients with risk factors for severe illness were prospectively enrolled as a treatment group with nirmatrelvir/ritonavir therapy versus a control group with supportive care. Serial viral load and culture from the upper respiratory tract were evaluated for seven days, and clinical responses and adverse reactions were evaluated for 28 days. RESULTS: A total of 51 patients were analyzed including 40 in the treatment group and 11 in the control group. Faster symptom resolution during hospitalization (P = 0.048) was observed in the treatment group. Only minor adverse reactions were reported in 27.5% of patients. The viral load on Day 7 was lower in the treatment group (P = 0.002). The viral culture showed a positivity of 67.6% (25/37) vs. 100% (6/6) on Day 1, 0% (0/37) vs. 16.7 (1/6) on Day 5, and 0% (0/16) vs. 50.0% (2/4) on Day 7 in the treatment and control groups, respectively. CONCLUSIONS: Nirmatrelvir/ritonavir against the omicron was safe and resulted in negative viral culture conversion after Day 5 of treatment with better symptomatic resolution.

Treatment for Immune Thrombocytopenia in Coronavirus Disease 2019 (COVID-19) Infection after COVID-19 Vaccination: A Case Report.

Thrombocytopenia is one of the rare signs of both the coronavirus disease 2019 (COVID-19) and COVID-19 vaccination. An 85-year-old man was diagnosed with immune thrombocytopenia and COVID-19, 7 days after COVID-19 vaccination. The patient was successfully treated with a short course of intravenous immunoglobulin and oral corticosteroids.

Breakthrough COVID-19 Infection During the Delta Variant Dominant Period: Individualized Care Based on Vaccination Status Is Needed.

BACKGROUND: The clinical features of coronavirus disease 2019 (COVID-19) patients in the COVID-19 vaccination era need to be clarified because breakthrough infection after vaccination is not uncommon. METHODS: We retrospectively analyzed hospitalized COVID-19 patients during a delta variant-dominant period 6 months after the national COVID-19 vaccination rollout. The clinical characteristics and risk factors for severe progression were assessed and subclassified according to vaccination status. RESULTS: A total of 438 COVID-19 patients were included; the numbers of patients in the unvaccinated, partially vaccinated and fully vaccinated groups were 188 (42.9%), 117 (26.7%) and 133 (30.4%), respectively. The vaccinated group was older, less symptomatic and had a higher Charlson comorbidity index at presentation. The proportions of patients who experienced severe progression in the unvaccinated and fully vaccinated groups were 20.3% (31/153) and 10.8% (13/120), respectively. Older age, diabetes mellitus, solid cancer, elevated levels of lactate dehydrogenase and chest X-ray abnormalities were associated with severe progression, and the vaccination at least once was the only protective factor for severe progression. Chest X-ray abnormalities at presentation were the only predictor for severe progression among fully vaccinated patients. CONCLUSION: In the hospitalized setting, vaccinated and unvaccinated COVID-19 patients showed different clinical features and risk of oxygen demand despite a relatively high proportion of patients in the two groups. Vaccination needs to be assessed as an initial checkpoint, and chest X-ray may be helpful for predicting severe progression in vaccinated patients.

Clinical Characteristics of COVID-19: Use of Steroids in Mostly Unvaccinated COVID-19 Patients Before the Omicron Variant.

BACKGROUND: Glucocorticoids are one of the current standard agents for moderate to severe coronavirus disease 2019 (COVID-19) treatment based on the RECOVERY trial. Data on the real clinical application of steroids for COVID-19 are scarce and will help guide the optimal use of steroids. We described the current prescription pattern of steroids for COVID-19 and investigated the factors related to specific practices. METHODS: All adults aged ≥ 19 years who were diagnosed with COVID-19 by real-time reverse transcription-polymerase chain reaction and admitted to one of 3 study hospitals from 8 December 2020 to 30 June 2021 were enrolled. Demographic and clinical data, including medications and oxygen therapy, were retrospectively collected from electronic medical records. The severity of comorbidities and COVID-19 were measured. The subjects were divided into steroid and nonsteroid groups, and the steroid group was then subdivided into standard and higher/longer groups. RESULTS: Among a total of 805 patients, 217 (27.0%) were treated with steroids. The steroid group showed a higher rate of oxygen therapy (81.1% vs. 2.7%), more concomitant use of remdesivir (77.4% vs. 1.4%) or antibiotics (79.3% vs. 4.3%), and a higher proportion of high risk according to National Early Warning Score-2 score (30.0% vs. 0.9%) or severe risk according to National Institute of Allergy and Infectious Disease Ordinal Scale score (81.1% vs. 2.7%) than the nonsteroid group. The mortality of the steroid group was 4.6%. In the steroid group, 82.5% received a standard or lower dose of steroids within ten days, and 17.5% (38/217) received a higher or longer dose of steroids. Multivariate analysis showed that initial lymphopenia (adjusted odds ratio [aOR], 0.94; 95% confidence interval [CI], 0.89-0.99) and high level of lactate dehydrogenase (LDH) (aOR, 1.00; 95% CI, 1.00-1.01) were independent risk factors for higher doses or longer steroid use. CONCLUSION: The dose and duration of steroids were in line with current guidelines in 82.5% of COVID-19 patients, but the outliers may need tailored therapy according to surrogate markers, such as initial lymphopenia or high level of LDH.

Early Oxygen Requirement in Patients with Mild-to-Moderate COVID-19 Who Received Regdanvimab after Delta-Variant Outbreak.

BACKGROUND: Regdanvimab is a monoclonal antibody targeted against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and a treatment option for patients with mild-to moderate coronavirus disease 2019 (COVID-19). However, there has been limited information on the clinical effectiveness of regdanvimab in the Delta variant of SARS-CoV-2. Therefore, we aimed to investigate the effectiveness of regdanvimab after the Delta variant was dominant using chronological analysis of regdanvimab use in a real-world setting. MATERIALS AND METHODS: The electrical medical records of patients infected with mild-to-moderate COVID-19 who received regdanvimab within 7 days of symptom onset were reviewed before (February - June 2021) and after (August - November 2021) the Delta variant became predominant in Korea. Clinical outcomes were assessed by the need for oxygen supplementation, time from symptom onset to oxygen requirement, in-hospital mortality, and length of hospitalization. To match the difference between the basic characteristics of the two groups, the clinical outcomes were compared again after 1 : 1 propensity score matching. RESULTS: Patients treated with regdanvimab in the Delta-predominant group were more likely to require oxygen supplementation (17.5% vs. 6.0%, P = 0.019) and had shorter times from symptom onset to supplemental oxygen use (mean ± standard deviation [SD]: 5.8 ± 2.8 vs. 10.0 ± 3.7, P = 0.007) than those in the control group. After propensity score matching, the percentage of patient requiring oxygen supplementation was higher (15.2% vs. 6.1%, P = 0.156), while the time from symptom onset to oxygen supplementation was significantly shorter in the Delta-predominant group (mean ± SD: 4.9 ± 2.1 vs. 10.0 ± 3.7, P = 0.007) than that in the control group. CONCLUSION: Considering that high proportion of vaccinated patients in the Delta-predominant group, this finding suggests the uncertainty whether the effect of regdanvimab is maintained even during the Delta-predominant period. It is hence necessary to continuously monitor the effectiveness of regdanvimab as new SARS-CoV-2 variants emerge.

Effectiveness of Regdanvimab at Preventing the Need for Oxygen Therapy in Patients with Mild-to-Moderate COVID-19: A Retrospective Cohort Study.

BACKGROUND: Monoclonal antibodies are a treatment option for patients with mild-to-moderate coronavirus disease (COVID-19). We investigated the effectiveness of regdanvimab, an anti-severe acute respiratory syndrome coronavirus-2 monoclonal antibody approved in Korea, in the treatment of patients with mild-to-moderate COVID-19. MATERIALS AND METHODS: Medical records of patients who were admitted to a COVID-19 designated hospital during the study period of February 1 to June 31 and met the indications for administration of regdanvimab were reviewed to assess baseline characteristics and clinical outcomes such as supplemental oxygen requirements, mortality, and length of hospitalization. Multivariable logistic regression analysis was conducted to identify factors associated with requiring supplemental oxygen. Subgroup analysis was performed according to the presence of pneumonia confirmed on a chest X-ray. RESULTS: Three hundred ninety-eight COVID-19 patients were included in the study, and 65 (16.3%) of them were administered regdanvimab. The proportion of patients requiring supplemental oxygen was significantly lower in the regdanvimab group than in the control group (6.2% vs. 20.1%, P = 0.007). There was no significant difference in mortality (0% vs. 1.5%, P >0.999) and the length of hospitalization (median: 10 days vs. 10 days, P = 0.267) between two groups. The multivariable analysis demonstrated that administration of regdanvimab was independently associated with lower oxygen supplement [odds ratio (OR): 0.20, 95% confidence interval (CI): 0.06 - 0.55, P = 0.004] after adjustment of potential risk factors related to supplemental oxygen including age, sex, chest X-ray abnormality, and underlying chronic kidney disease. Among the patients with pneumonia radiologically, administration of regdanvimab was also associated with lower risk of oxygen supplement (OR: 0.13, 95% CI: 0.02 - 0.46, P = 0.007). CONCLUSION: Regdanvimab use was related to lower need for supplemental oxygen in patients with mild-to-moderate COVID-19 for the indications for administration of regdanvimab.

Changes in Anxiety Level and Personal Protective Equipment Use Among Healthcare Workers Exposed to COVID-19.

BACKGROUND: The relationship between changes in anxiety levels and personal protective equipment (PPE) use is yet to be evaluated. The present study assessed this relationship among healthcare workers (HCWs) involved in the care of patients with coronavirus disease 2019 (COVID-19). METHODS: An online survey was conducted in a municipal hospital with 195 nationally designated negative pressure isolation units in Korea. Anxiety level was measured using the self-rating anxiety scale (SAS), and changes in anxiety levels were assessed based on the time when COVID-19 vaccine was introduced in March 2021 in Korea. Monthly PPE usage between June 2020 and May 2021 was investigated. RESULTS: The mean SAS score (33.25 ± 5.97) was within normal range and was lower than those reported in previous studies conducted before COVID-19 vaccination became available. Among the 93 HCWs who participated, 64 (68.8%) answered that their fear of contracting COVID-19 decreased after vaccination. The number of coveralls used per patient decreased from 33.6 to 0. However, a demand for more PPE than necessary was observed in situations where HCWs were exposed to body fluids and secretions (n = 38, 40.9%). Excessive demand for PPE was not related to age, working experience, or SAS score. CONCLUSION: Anxiety in HCWs exposed to COVID-19 was lower than it was during the early period of the pandemic, and the period before vaccination was introduced. The number of coveralls used per patient also decreased although an excessive demand for PPE was observed.

Impact of the COVID-19 pandemic on travel behavior: A case study of domestic inbound travelers in Jeju, Korea.

This study analyzes a large-scale navigation dataset that captures travel activities of domestic inbound visitors in Jeju, Korea in the first nine months of 2020. A collection of regression models are introduced to quantify the dynamic effects of local and national COVID-19 indicators on their travel behavior. Results suggest that behavior of inbound travelers was jointly affected by pandemic severity locally and remotely. The daily number of new cases in Jeju has a greater impact on reducing travel activities than the national-level daily new cases of COVID-19. The impacts of the pandemic did not diminish over time but produced heterogeneous effects on travels with different trip purposes. Our findings reveal the persistence of COVID-19's effects on travel behavior and the variability in travelers' responses across tourism activities with different levels of perceived health risks. The implications for crisis management and recovery strategies are also discussed.

Guest editorial

[...]COVID-19 accelerated digitization, as consumers leapt forward five years in digital adoption in just two months of the pandemic (McKinsey & Co., 2020a). The rapid development of information technology facilitates the sharing of consumer-service experiences and their positive or negative reflections as part of co-creation activities that potentially informs brand development and reputation (Binkhorst and Den Dekker, 2009;Au et al., 2014), with brand reputation being of a particular importance, as it has a direct impact on competitiveness and profitability (Anagnostopoulou et al., 2020;Viglia et al., 2016). Numerous studies in tourism and hospitality have discussed brand management and co-creation separately, but academic attempts to integrate two important themes have been more limited. [...]the purpose of this special issue of Journal of Product and Brand Management is to explore brand management and co-creation in tourism and hospitality contexts using a variety of issues, concepts and examples. Govers and Go (2009) defined place brands as “representations of place identity, building a favourable internal (public, private and civil society stakeholders) and external (tourists, investors, traders, migrants) image”, leading to brand equity;that is, brand satisfaction and loyalty;name awareness;perceived quality;and other favourable brand associations (that is, positive image and reputation) attached to a name or symbol representing a country, city or region.

Effects of Storage Temperature and Media/Buffer for SARS-CoV-2 Nucleic Acid Detection.

OBJECTIVES: The increase in the number of patients with coronavirus disease 2019 (COVID-19) has delayed real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), requiring proper shipping and storage conditions, especially in hot weather. This study aims to assess how some conditions, such as storage period, temperature, media or buffer, and sample types, affect the results of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RT-qPCR. METHODS: SARS-CoV-2-positive specimens were collected from Boramae Medical Center for 2 months (from May to June 2020) and stored in different media or buffers at different temperatures. RESULTS: As a result of examining confirmed patient samples, RT-qPCR results were not significantly affected by 2°C to 8°C storage until after 7 days. When stored at 20°C to 22°C or above 35°C, the results were affected negatively even after 1 day. Higher storage temperatures resulted in a lower probability of detecting viral nucleic acids because of degradation. Samples stored in pH-controlled media or buffer were more stable than those stored in nonbuffer states. CONCLUSIONS: These results emphasize the importance of storage temperature and media or buffer and performing RT-qPCR for SARS-CoV-2 nucleic acid detection as soon as possible after sample collection.