A systematic review and meta-analysis of long-term sequelae of COVID-19 2-year after SARS-CoV-2 infection: A call to action for neurological, physical, and psychological sciences.

Long-term sequelae conditions of COVID-19 at least 2-year following SARS-CoV-2 infection are unclear and little is known about their prevalence, longitudinal trajectory, and potential risk factors. Therefore, we conducted a comprehensive meta-analysis of survivors' health-related consequences and sequelae at 2-year following SARS-CoV-2 infection. PubMed/MEDLINE, CENTRAL, and EMBASE were systematically searched up to February 10, 2023. A systematic review and meta-analysis were performed to calculate the pooled effect size, expressed as event rate (ER) with corresponding 95% confidence interval (CI) of each outcome. Twelve studies involving 1 289 044 participants from 11 countries were included. A total of 41.7% of COVID-19 survivors experienced at least one unresolved symptom and 14.1% were unable to return to work at 2-year after SARS-CoV-2 infection. The most frequent symptoms and investigated findings at 2-year after SARS-CoV-2 infection were fatigue (27.4%; 95% CI 17%-40.9%), sleep difficulties (25.1%; 95% CI 22.4%-27.9%), impaired diffusion capacity for carbon monoxide (24.6%; 95% CI 10.8%-46.9%), hair loss (10.2%; 95% CI 7.3%-14.2%), and dyspnea (10.1%; 95% CI 4.3%-21.9%). Individuals with severe infection suffered more from anxiety (OR = 1.69, 95% CI 1.17-2.44) and had more impairments in forced vital capacity (OR = 9.70, 95% CI 1.94-48.41), total lung capacity (OR = 3.51, 95% CI 1.77-6.99), and residual volume (OR = 3.35, 95% CI 1.85-6.07) after recovery. Existing evidence suggest that participants with a higher risk of long-term sequelae were older, mostly female, had pre-existing medical comorbidities, with more severe status, underwent corticosteroid therapy, and higher inflammation at acute infection. Our findings suggest that 2-year after recovery from SARS-CoV-2 infection, 41.7% of survivors still suffer from either neurological, physical, and psychological sequela. These findings indicate that there is an urgent need to preclude persistent or emerging long-term sequelae and provide intervention strategies to reduce the risk of long COVID.

Unraveling the socio-environmental drivers during the early COVID-19 pandemic in China.

The effect of environmental and socioeconomic conditions on the global pandemic of COVID-19 had been widely studied, yet their influence during the early outbreak remains less explored. Unraveling these relationships represents a key knowledge to prevent potential outbreaks of similar pathogens in the future. This study aims to determine the influence of socioeconomic, infrastructure, air pollution, and weather variables on the relative risk of infection in the initial phase of the COVID-19 pandemic in China. A spatio-temporal Bayesian zero-inflated Poisson model is used to test for the effect of 13 socioeconomic, urban infrastructure, air pollution, and weather variables on the relative risk of COVID-19 disease in 122 cities of China. The results show that socioeconomic and urban infrastructure variables did not have a significant effect on the relative risk of COVID-19. Meanwhile, COVID-19 relative risk was negatively associated with temperature, wind speed, and carbon monoxide, while nitrous dioxide and the human modification index presented a positive effect. Pollution gases presented a marked variability during the study period, showing a decrease of CO. These findings suggest that controlling and monitoring urban emissions of pollutant gases is a key factor for the reduction of risk derived from COVID-19.

Lung and physical function in post COVID-19 and clinical and functional associations: a cross-sectional study in Brazil.

OBJECTIVE: The purpose of this study was to assess exercise capacity, lung and physical function in COVID-19 survivors, and the association of lesion-level characteristics assessed by chest computed tomography, probable sarcopenia, and percentage of diffusing capacity of the lung for carbon monoxide with clinical and functional variables. METHODS: This study was conducted in Salvador, Bahia, Brazil. All patients had a laboratory-confirmed SARS-CoV-2 infection. The sociodemographic characteristics, COVID-19 exposure history, pulmonary function, computed tomography, and functionality of the participants between 1 and 3 months of diagnosis of the disease were collected. RESULTS: A total of 135 patients after COVID-19 recovery were included in this study. Probable sarcopenia, reduction in percentage of diffusing capacity of the lung for carbon monoxide, and a lower 6-min walk distance were observed after COVID-19 infection. Computed tomography>50% was associated with a longer length of stay and a lower percentage of diffusing capacity of the lung for carbon monoxide. Probable sarcopenia diagnosis was associated with a worse percentage of the predicted 6-min walk distance in relation to the predicted, absolute 6-min walk distance (m), percentage of diffusing capacity of the lung for carbon monoxide, and percentage of total lung capacity. CONCLUSION: Muscle disability and lung dysfunction are common in COVID-19 survivors. Hospitalization was associated with the worst muscle force and diffusing capacity of the lung for carbon monoxide. Computed tomography characteristics could be a marker of prolonged hospital stay after the acute phase of COVID-19. Additionally, the probable diagnosis of sarcopenia could be a marker of impact on walking distance. These results highlight the need for long-term follow-up of those patients and rehabilitation programs.

Investigation in PO blending and compression ratio on engine performance and gas emissions including environmental health risk assessment and economic analysis.

Waste management and mitigation is the primary necessity across the globe. The daily use of plastic materials in different forms emergence the plastic pollutions, and it has been significantly increased during the COVID-19 pandemic. Thus, mitigation of waste plastics generation is one of the major challenges in the present situation. The present study addressed the conversion of waste plastics into value-added products such as liquid hydrocarbon fuels and their application in reducing greenhouse gas emissions. A comprehensive investigation has been performed on engine performance and combustion characteristics at various compression ratios and PO blending. The effect of liquid fuel blending with commercial diesel was investigated at three different compression ratios (15.1, 16.2, and 16.7) under various BMEP conditions. The results revealed that blending of liquid fuel produced from waste plastic can improve the BTE significantly, and the highest 35.77% of BTE was observed for 10% blending at 15.1 CR. While the lowest BSFC of 5.77 × 10-5 kg/kW-s was estimated for 20% PO blending at 16.7 CR under optimum BMEP (4.0 bar) conditions. The investigation of combustion parameters such as cylinder pressure, net heat release rate, rate of pressure rise, and cumulative heat release showed that it increases with the compression ratio from 15.1 to 16.7. At the same time, the emissions of CO, CO2, and unburnt hydrocarbon was decreased significantly. The economic analysis for the present lab-scale study estimated that approximately ₹12.17 ($0.15) profit per liter is possible in the 1st year, while the significant profit starts from the 2nd year onward, which is in the range of ₹59.78-₹84.48 ($0.75-$1.07) when the PO is blended with CD within the permissible limits as per the norms.

Evolution and long­term respiratory sequelae after severe COVID-19 pneumonia: nitric oxide diffusion measurement value.

INTRODUCTION: There are no published studies assessing the evolution of combined determination of the lung diffusing capacity for both nitric oxide and carbon monoxide (DLNO and DLCO) 12 months after the discharge of patients with COVID-19 pneumonia. METHODS: Prospective cohort study which included patients who were assessed both 3 and 12 months after an episode of SARS-CoV-2 pneumonia. Their clinical status, health condition, lung function testings (LFTs) results (spirometry, DLNO-DLCO analysis, and six-minute walk test), and chest X-ray/computed tomography scan images were compared. RESULTS: 194 patients, age 62 years (P25-75, 51.5-71), 59% men, completed the study. 17% required admission to the intensive care unit. An improvement in the patients' exercise tolerance, the extent of the areas of ground-glass opacity, and the LFTs between 3 and 12 months following their hospital discharge were found, but without a decrease in their degree of dyspnea or their self-perceived health condition. DLNO was the most significantly altered parameter at 12 months (19.3%). The improvement in DLNO-DLCO mainly occurred at the expense of the recovery of alveolar units and their vascular component, with the membrane factor only improving in patients with more severe infections. CONCLUSIONS: The combined measurement of DLNO-DLCO is the most sensitive LFT for the detection of the long-term sequelae of COVID-19 pneumonia and it explain better their pathophysiology.

Influence of the COVID-19 pandemic on causes for the development of carbon monoxide intoxications.

Introduction: Several causes can lead to carbon monoxide (CO) intoxication. A first-line treatment option for such intoxications is hyperbaric oxygenation (HBO2) therapy. The COVID-19 pandemic has been changing everyday life in Germany since March 2020, mainly caused by statutory provisions. Our aim was to review whether these changes have an influence on the causes and frequency for the development of CO intoxication. Methods: We retrospectively analyzed the data of patients who were treated for CO intoxication in our institution between April 2019 and March 2021. Besides demographic data, we compared the overall number and documented causes for each CO intoxication in the period of April 2020 to March 2021 with the period between April 2019 and March 2020. Results: After applying inclusion and exclusion criteria, 139 patients were included. We found a significant decrease in the overall number of patients who needed treatment since the beginning of the COVID-19 pandemic. However, the share of CO intoxication caused by the indoor use of coal stoves, coal barbecue, or suicide attempts increased. In contrast, the share of cases caused by apartment or house fire, smoking waterpipe, or gas stoves decreased. Conclusion: The COVID-19 pandemic and the associated restrictions lead to a significant reduction in the number of patients in need for HBO2 therapy due to CO-Intoxication. The causes leading to CO intoxication also changed since the beginning of the COVID-19 pandemic. We observed a shift toward causes related to the indoor use of coal-fired stoves and barbecues as well as suicide attempts.

Economic and Environmental Impact of Digital Health App Video Consultations in Follow-up Care for Patients in Orthopedic and Trauma Surgery in Germany: Randomized Controlled Trial.

BACKGROUND: Following the Riyadh Declaration, digital health technologies were prioritized in many countries to address the challenges of the COVID-19 pandemic. Digital health apps for telemedicine and video consultations help reduce potential disease spread in routine health care, including follow-up care in orthopedic and trauma surgery. In addition to the satisfaction, efficiency, and safety of telemedicine, its economic and environmental effects are highly relevant to decision makers, particularly for the goal of reaching carbon neutrality of health care systems. OBJECTIVE: This study aims to provide the first comprehensive health economic and environmental analysis of video consultations in follow-up care after knee and shoulder interventions in an orthopedic and trauma surgery department of a German university hospital. The analysis is conducted from a societal perspective. We analyze both economic and environmental impacts of video consultations, taking into account the goal of carbon neutrality for the German health care system by 2030. METHODS: We conducted a prospective randomized controlled trial comparing follow-up care with digital health app video consultations (intervention group) to conventional face-to-face consultations in the clinic (control group). Economic impact included the analysis of travel and time costs and production losses. Examination of the environmental impact comprised the emissions of greenhouse gases, carbon monoxide, volatile hydrocarbons, nitrogen oxides, and particulates, and the calculation of environmental costs. Sensitivity analysis included calculations with a higher cost per ton of carbon dioxide equivalent, which gives equal weight to the welfare of present and future generations. RESULTS: Data from 52 patients indicated that, from the patients' point of view, telemedicine helped reduce travel costs, time costs, and production losses, resulting in mean cost savings of €76.52 per video consultation. In addition, emissions of 11.248 kg of greenhouse gases, 0.070 kg of carbon monoxide, 0.011 kg of volatile hydrocarbons, 0.028 kg of nitrogen oxides, and 0.0004 kg of particulates could be saved per patient through avoided travel. This resulted in savings of environmental costs between €3.73 and €9.53 per patient. CONCLUSIONS: We presented the first comprehensive analysis of economic and environmental effects of telemedicine in the follow-up care of patients in orthopedic and trauma surgery in Germany. Video consultations were found to reduce the environmental footprint of follow-up care; saved travel costs, travel time, and time costs for patients; and helped to lower production losses. Our findings can support the decision-making on the use of digital health during and beyond the COVID-19 pandemic, providing decision makers with data for both economic and environmental effects. Thanks to the pragmatic design of our study, our findings can be applied to a wide range of clinical contexts and potential digital health applications that substitute outpatient hospital visits with video consultations. TRIAL REGISTRATION: German Clinical Trials Register DRKS00023445; https://tinyurl.com/4pcvhz4n.

Changes in self-harm attempts after the COVID-19 pandemic based on pre-hospital medical records.

Although many concerns have been raised on increased self-harm or suicide attempts since the emergence of the coronavirus disease 2019 (COVID-19) pandemic, the numbers of studies reported no consistent increase. This study aimed to analyze the data on the request for emergency medical service (EMS) in Daegu Metropolitan City in Korea to investigate the effects of the COVID-19 pandemic on the incidence and types of suicidal patients. Data of 4480 cases requesting EMS related to self-harm or suicide 1 year before and after the COVID-19 pandemic were retrospectively comparatively analyzed (February 19, 2019-February 18, 2021). The number of EMS requests for self-harm and suicide increased after the pandemic compared to that before the pandemic (daily mean request 5.83 [±2.597] vs 6.43 [±2.918]). In particular, the number of female patients increased per day on average (2.61 [±1.717] vs 3.17 [±1.893]). With respect to the reasons for the request, committed self-harm and attempts to commit self-harm increased, whereas the presumption against suicide decreased. With respect to consciousness levels, the number of alert patients increased, whereas the number of transport cases decreased. For the method of the attempt, hanging and carbon monoxide/gas poisoning decreased, whereas jumping from a height and drowning increased. The number of patients with psychiatric history and those with other chronic illnesses increased. In multivariate regression analysis, women (OR 1.227, 95% CI = 1.072-1.405, P = .003), patients with psychiatric diseases (OR 1.223, 95% CI = 1.031-1.450, P = .021), patients with other chronic illnesses (OR 1.510, 95% CI = 1.127-2.023, P = .006), and CO or gas poisoning (not attempted) (OR 1.349, 95% CI = 1.038-1.753, P = .025) showed statistically significant differences. Among the request for EMS, requests for committed self-harm and attempts to commit suicide increased. Medical support and measures for mental health and emergency medical systems should be established for female patients and patients with psychiatric or other chronic diseases.

Changes in Air Quality and Drivers for the Heavy PM2.5 Pollution on the North China Plain Pre- to Post-COVID-19.

Under the clean air action plans and the lockdown to constrain the coronavirus disease 2019 (COVID-19), the air quality improved significantly. However, fine particulate matter (PM2.5) pollution still occurred on the North China Plain (NCP). This study analyzed the variations of PM2.5, nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and ozone (O3) during 2017-2021 on the northern (Beijing) and southern (Henan) edges of the NCP. Furthermore, the drivers for the PM2.5 pollution episodes pre- to post-COVID-19 in Beijing and Henan were explored by combining air pollutant and meteorological datasets and the weighted potential source contribution function. Results showed air quality generally improved during 2017-2021, except for a slight rebound (3.6%) in NO2 concentration in 2021 in Beijing. Notably, the O3 concentration began to decrease significantly in 2020. The COVID-19 lockdown resulted in a sharp drop in the concentrations of PM2.5, NO2, SO2, and CO in February of 2020, but PM2.5 and CO in Beijing exhibited a delayed decrease in March. For Beijing, the PM2.5 pollution was driven by the initial regional transport and later secondary formation under adverse meteorology. For Henan, the PM2.5 pollution was driven by the primary emissions under the persistent high humidity and stable atmospheric conditions, superimposing small-scale regional transport. Low wind speed, shallow boundary layer, and high humidity are major drivers of heavy PM2.5 pollution. These results provide an important reference for setting mitigation measures not only for the NCP but for the entire world.

Environmental factors influencing the risk of ANCA-associated vasculitis.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of diseases characterized by inflammation and destruction of small and medium-sized blood vessels. Clinical disease phenotypes include microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The incidence of AAV has been on the rise in recent years with advances in ANCA testing. The etiology and pathogenesis of AAV are multifactorial and influenced by both genetic and environmental factors, as well as innate and adaptive immune system responses. Multiple case reports have shown that sustained exposure to silica in an occupational environment resulted in a significantly increased risk of ANCA positivity. A meta-analysis involving six case-control studies showed that silica exposure was positively associated with AAV incidence. Additionally, exposure to air pollutants, such as carbon monoxide (CO), is a risk factor for AAV. AAV has seasonal trends. Studies have shown that various environmental factors stimulate the body to activate neutrophils and expose their own antigens, resulting in the release of proteases and neutrophil extracellular traps, which damage vascular endothelial cells. Additionally, the activation of complement replacement pathways may exacerbate vascular inflammation. However, the role of environmental factors in the etiology of AAV remains unclear and has received little attention. In this review, we summarized the recent literature on the study of environmental factors, such as seasons, air pollution, latitude, silica, and microbial infection, in AAV with the aim of exploring the relationship between environmental factors and AAV and possible mechanisms of action to provide a scientific basis for the prevention and treatment of AAV.

Effects of Air Pollution on Chemosensory Dysfunction in COVID-19 Patients.

BACKGROUND: In some patients, coronavirus disease 2019 (COVID-19) is accompanied by loss of smell and taste, and this has been reportedly associated with exposure to air pollutants. This study investigated the relationship between the occurrence of chemosensory dysfunction in COVID-19 patients and air pollutant concentrations in Korea. METHODS: Information on the clinical symptom of chemosensory dysfunction, the date of diagnosis, residential area, age, and sex of 60,194 confirmed COVID-19 cases reported to the Korea Disease Control and Prevention Agency from January 20 to December 31, 2020 was collected. In addition, the daily average concentration of air pollutants for a week in the patients' residential area was collected from the Ministry of Environment based on the date of diagnosis of COVID-19. A binomial logistic regression model, using age and gender, standardized smoking rate, number of outpatient visits, 24-hour mean temperature and relative humidity at the regional level as covariates, was used to determine the effect of air pollution on chemosensory dysfunction. RESULTS: Symptoms of chemosensory dysfunction were most frequent among patients in their 20s and 30s, and occurred more frequently in large cities. The logistic analysis showed that the concentration of particulate matter 10 (PM10) and 2.5 (PM2.5) up to 2 days before the diagnosis of COVID-19 and the concentration of sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) at least 7 days before the diagnosis of COVID-19 affected the development of chemosensory dysfunction. In the logistic regression model adjusted for age, sex, standardized smoking rate, number of outpatient visits, and daily average temperature and relative humidity, it was found that an increase in the interquartile range of PM10, PM2.5, SO2, NO2, and CO on the day of diagnosis increased the incidence of chemosensory dysfunction 1.10, 1.10, 1.17, 1.31, and 1.19-fold, respectively. In contrast, the O3 concentration had a negative association with chemosensory dysfunction. CONCLUSION: High concentrations of air pollutants such as PM10, PM2.5, SO2, NO2, and CO on the day of diagnosis increased the risk of developing chemosensory dysfunction from COVID-19 infection. This result underscores the need to actively prevent exposure to air pollution and prevent COVID-19 infection. In addition, policies that regulate activities and products that create high amounts of harmful environmental wastes may help in promoting better health for all during COVID-19 pandemic.

Differences in lung function between major race/ethnicity groups following hospitalization with COVID-19.

BACKGROUND: Ethnic minorities have higher rates of infection, hospitalization, and death from COVID-19 compared to White Americans. RESEARCH QUESTION: Is race/ethnicity an independent predictor of lung dysfunction following hospitalization with COVID-19? STUDY DESIGN: and Methods: Patients hospitalized at the University of Virginia Medical Center with COVID-19 underwent a questionnaire within 30 days following discharge. Those who had persistent respiratory symptoms were invited to complete spirometry, lung volumes, and diffusion capacity of carbon monoxide. 128 completed pulmonary function testing at 6 months. RESULTS: Impairments in lung function were present in spirometry, lung volumes, and diffusion capacity of carbon monoxide at 6 months. The most prevalent impairments were noted in FVC (24.4%), FEV1 (20.5%), TLC (23.3%), and DLCO (20.8%). When compared between race/ethnicity groups three lung function parameters demonstrated statistically significant difference, including FEV1/FVC (p = 0.021), RV/TLC (p = 0.006) and DLCO % predicted (p = 0.002). The average difference between Hispanic and non-Hispanic Black patients with respect to DLCO % predicted was 13.09 (p = 0.01) and the average difference between non-Hispanic White and non-Hispanic Black patients was 9.46 (p = 0.04). Differences persisted when controlling for age, BMI, smoking status, history of chronic lung disease, ICU admission, treatment with corticosteroids, and socioeconomic status. INTERPRETATION: Long-term impairments in lung function following COVID-19 are common, occurring in roughly 22% of patients and across all three major domains of lung function. Non-Hispanic Black race/ethnicity was associated with a statistically significant lower DLCO % predicted when compared to non-Hispanic White and Hispanic patients.

Recovery of functional fitness, lung function, and immune function in healthcare workers with nonsevere and severe COVID-19 at 13 months after discharge from the hospital: a prospective cohort study.

OBJECTIVES: This study aimed to evaluate the recovery of functional fitness, lung function, and immune function in healthcare workers (HCWs) with nonsevere and severe COVID-19 at 13 months after discharge from the hospital. METHODS: The participants of "Rehabilitation Care Project for Medical Staff Infected with COVID-19" underwent a functional fitness test (muscle strength, flexibility, and agility/dynamic balance), lung function test, and immune function test (including cytokines and lymphocyte subsets) at 13 months after discharge. RESULTS: The project included 779 HCWs (316 nonsevere COVID-19 and 463 severe COVID-19). This study found that 29.1% (130/446) of the HCWs have not yet recovered their functional fitness. The most affected lung function indicator was lung perfusion capacity (34% with diffusion capacity for carbon monoxide-single breath <80%). The increase of interleukin-6 (64/534, 12.0%) and natural killer cells (44/534, 8.2%) and the decrease of CD3+ T cells (58/534, 10.9%) and CD4+ T cells (26/534, 4.9%) still existed at 13 months after discharge. No significant difference was found in the HCWs with nonsevere and severe COVID-19 regarding recovery of functional fitness, lung function, and immune function at 13 months after discharge. CONCLUSION: The majority of Chinese HCWs with COVID-19 had recovered their functional fitness, lung function, and immune function, and the recovery status in HCWs with severe COVID-19 is no worse than that in HCWs with nonsevere COVID-19 at 13 months after discharge from the hospital.

The impact of air pollution on COVID-19 incidence, severity, and mortality: A systematic review of studies in Europe and North America.

BACKGROUND: Air pollution is speculated to increase the risks of COVID-19 spread, severity, and mortality. OBJECTIVES: We systematically reviewed studies investigating the relationship between air pollution and COVID-19 cases, non-fatal severity, and mortality in North America and Europe. METHODS: We searched PubMed, Web of Science, and Scopus for studies investigating the effects of harmful pollutants, including particulate matter with diameter ≤2.5 or 10 µm (PM2.5 or PM10), ozone (O3), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO), on COVID-19 cases, severity, and deaths in Europe and North America through to June 19, 2021. Articles were included if they quantitatively measured the relationship between exposure to air pollution and COVID-19 health outcomes. RESULTS: From 2,482 articles screened, we included 116 studies reporting 355 separate pollutant-COVID-19 estimates. Approximately half of all evaluations on incidence were positive and significant associations (52.7%); for mortality the corresponding figure was similar (48.1%), while for non-fatal severity this figure was lower (41.2%). Longer-term exposure to pollutants appeared more likely to be positively associated with COVID-19 incidence (63.8%). PM2.5, PM10, O3, NO2, and CO were most strongly positively associated with COVID-19 incidence, while PM2.5 and NO2 with COVID-19 deaths. All studies were observational and most exhibited high risk of confounding and outcome measurement bias. DISCUSSION: Air pollution may be associated with worse COVID-19 outcomes. Future research is needed to better test the air pollution-COVID-19 hypothesis, particularly using more robust study designs and COVID-19 measures that are less prone to measurement error and by considering co-pollutant interactions.

Changes in temporal pattern and spatial distribution of environmental pollutants in 8 Asian countries owing to COVID-19 pandemic.

This study investigated the changes in air pollutant's concentration, spatio-temporal distribution and sensitivity of changes in air pollutant's concentration during pre and post COVID-19 outbreak. We employed Google Earth Engine Platform to access remote sensing datasets of air pollutants across Asian continent. Air pollution and cumulative confirmed-COVID cases data of Asian countries (Afghanistan, Bangladesh, China, India, Iran, Iraq, Pakistan, and Saudi Arabia) have been collected and analyzed for 2019 and 2020. The results indicate that aerosol index (AI) and nitrogen dioxide (NO2) is significantly reduced during COVID outbreak i.e. in year 2020. In addition, we found significantly positive (P < 0.05, 95% confidence interval, two-tailed) correlation between changes in AI and NO2 concentration for net active-COVID case increment in almost each country. For other atmospheric gases i.e. carbon monoxide (CO), formaldehyde (HCHO), ozone (O3), and Sulfur dioxide (SO2), insignificant and/or significant negative correlation is also observed. These results suggest that the atmospheric concentration of AI and NO2 are good indicators of human activities. Furthermore, the changes in O3 shows significantly negative correlation for net active-COVID case increment. In conclusion, we observed significant positive environmental impact of COVID-19 restrictions in Asia. This study would help and assist environmentalist and policy makers in restraining air pollution by implementing efficient restrictions on human activities with minimal economic loss.

An assessment of post-COVID-19 infection pulmonary functions in healthcare professionals.

BACKGROUND: The medium- and long-term effects of COVID-19 infection on pulmonary function are still unknown. The present study aimed to investigate the pulmonary functions in healthcare professionals who had persistent complaints after contracting COVID-19 and returning to work. METHODS: The study included COVID-19-infected healthcare professionals from the Düzce University Medical Faculty Hospital who volunteered to participate. Medical histories, medical records, pulmonary function tests, the diffusing capacity of the lungs for carbon monoxide (DLCO) test, and the 6-minute walk test (6MWT) were used to collect data from all participants. RESULTS: The study included 53 healthcare professionals, with an average age of 38 ± 10 years (min: 24 years and max: 71 years), including 29 female (54.7%) and 24 male (45.3%) participants. Of the participants, 22.6% were smokers, 35.8% (19 individuals) had comorbidities, and 17% (9 individuals) were hospitalized. The mean length of stay was 9 ± 4 days (mean ± standard deviation). The most prevalent symptoms were weakness (88.7%), muscle aches (67.9%), inability to smell/taste (60.4%), headache (54.7%), fever (45.3%), cough (41.5%), and shortness of breath (37.7%). The mean time to return to work after a positive polymerase chain reaction (PCR) test for COVID-19 was 18 ± 13 days. The average time among post-disease pulmonary function, 6MW, and DLCO tests was 89 ± 36 days (min: 15 and max: 205). The DLCO level decreased in 39.6% (21) of the participants. Female participants had a significantly higher rate of decreased DLCO levels than male participants (25% vs. 55.2%, P = .026). DLCO levels were significantly higher in participants with long-term persistent complaints (P = .043). The later the time to return to work, the lower the DLCO value (r = -0.290 and P = .035). The 6MWT distance was positively correlated with hemoglobin and lymphocyte levels at the time of the disease onset and negatively correlated with D-dimer levels. The most prevalent symptoms during the control visits were shortness of breath/effort dyspnea (24.6%), weakness (9.5%), and muscle aches (7.6%). CONCLUSION: Significant persistent complaints (47.2%) and low DLCO levels (39.6%) were observed in healthcare professionals during control visits at a mean time of 3 months after the COVID-19 infection. Symptoms and spirometry measurements, including DLCO, may be helpful in the follow-up of healthcare professionals who contracted COVID-19. Further comprehensive studies with long-term follow-up periods are required.

Persistent 129Xe MRI Pulmonary and CT Vascular Abnormalities in Symptomatic Individuals with Post-acute COVID-19 Syndrome.

BACKGROUND: In patients with post-acute COVID-19 syndrome (PACS), abnormal gas-transfer and pulmonary vascular density have been reported, but such findings have not been related to each other or to symptoms and exercise limitation. The pathophysiologic drivers of PACS in patients previously infected with COVID-19 who were admitted to in-patient treatment in hospital (or ever-hospitalized patients) and never-hospitalized patients are not well understood. PURPOSE: To determine the relationship of persistent symptoms and exercise limitation with xenon 129 (129Xe) MRI and CT pulmonary vascular measurements in individuals with PACS. MATERIALS AND METHODS: In this prospective study, patients with PACS aged 18-80 years with a positive polymerase chain reaction COVID-19 test were recruited from a quaternary-care COVID-19 clinic between April and October 2021. Participants with PACS underwent spirometry, diffusing capacity of the lung for carbon monoxide (DLco), 129Xe MRI, and chest CT. Healthy controls had no prior history of COVID-19 and underwent spirometry, DLco, and 129Xe MRI. The 129Xe MRI red blood cell (RBC) to alveolar-barrier signal ratio, RBC area under the receiver operating characteristic curve (AUC), CT volume of pulmonary vessels with cross-sectional area 5 mm2 or smaller (BV5), and total blood volume were quantified. St George's Respiratory Questionnaire, International Physical Activity Questionnaire, and modified Borg Dyspnea Scale measured quality of life, exercise limitation, and dyspnea. Differences between groups were compared with use of Welch t-tests or Welch analysis of variance. Relationships were evaluated with use of Pearson (r) and Spearman (ρ) correlations. RESULTS: Forty participants were evaluated, including six controls (mean age ± SD, 35 years ± 15, three women) and 34 participants with PACS (mean age, 53 years ± 13, 18 women), of whom 22 were never hospitalized. The 129Xe MRI RBC:barrier ratio was lower in ever-hospitalized participants (P = .04) compared to controls. BV5 correlated with RBC AUC (ρ = .44, P = .03). The 129Xe MRI RBC:barrier ratio was related to DLco (r = .57, P = .002) and forced expiratory volume in 1 second (ρ = .35, P = .03); RBC AUC was related to dyspnea (ρ = -.35, P = .04) and International Physical Activity Questionnaire score (ρ = .45, P = .02). CONCLUSION: Xenon 129 (129Xe) MRI measurements were lower in participants previously infected with COVID-19 who were admitted to in-patient treatment in hospital with post-acute COVID-19 syndrome, 34 weeks ± 25 after infection compared to controls. The 129Xe MRI measures were associated with CT pulmonary vascular density, diffusing capacity of the lung for carbon monoxide, exercise capacity, and dyspnea. Clinical trial registration no.: NCT04584671 © RSNA, 2022 Online supplemental material is available for this article See also the editorial by Wild and Collier in this issue.

National emissions inventory and future trends in greenhouse gases and other air pollutants from civil airports in China.

Civil aviation is an important source of air pollutants, but this field has received insufficient attention in China. Based on the standard emissions model of the International Civil Aviation Organization (ICAO) and actual flight information from 241 airports, this study estimated a comprehensive emissions inventory for 2010-2020 by considering the impacts of mixing layer height. The results showed that annual pollutant emissions rapidly trended upward along with population and economic growth; however, the emissions decreased owing to the impacts of the COVID-19 pandemic. In 2020, the emissions of carbon monoxide (CO), nitrogen oxides (NOX), particulate matter (PM), methane (CH4), nitrous oxide (N2O), carbon dioxide (CO2), and water vapor (H2O) were 34.34, 65.73, 0.10, 0.34, 0.40, 14,706.26, and 5733.11 Gg, respectively. The emissions of total volatile organic compounds (VOCs) from China's civil airports in 2020 were estimated at 17.20 Gg; the major components were formic acid (1.70 Gg), acetic acid (1.62 Gg), 1-butylene (1.03 Gg), acetone (0.96 Gg), and acetaldehyde (0.93 Gg). The distribution of pollutant emissions was consistent with the level of economic development, mainly in Beijing, Guangzhou, and Shanghai. In addition, we estimated future pollution trends for the aviation industry under four scenarios. Under the comprehensive scenario, which considered the impacts of economic growth, passenger turnover, cargo turnover, COVID-19, and technological efficiency, the levels of typical pollutants were expected to increase by nearly 1.51-fold from 2010 to 2035.

Three cases of clinically significant inaccurate carboxyhemoglobin measurement.

Background: Clinicians often rely on measurement of carboxyhemoglobin (COHb) to confirm or rule out a diagnosis of carbon monoxide (CO) poisoning. Methods: We report two cases of false negative COHb in patients with CO poisoning and one case of false positive COHb in a patient without CO poisoning. Results: In the first case, a 20-year-old male developed headache, confusion, and near-syncope while operating a gasoline-powered pressure washer in an enclosed space. In the emergency department (ED), his COHb was 1.8%, but this level was disregarded, and he was referred for hyperbaric oxygen. His COHb just before hyperbaric oxygen was 4.1%, and later analysis of his blood collected at ED arrival revealed a COHb of 20.1%. The referral ED blood gas machine calibration and controls were within specification. In the second case, a 45-year-old male presented with several others to the ED with symptoms of CO poisoning after exposure at a conference. All others had elevated COHb levels, but his COHb was 2%. He was discharged but returned shortly with continued symptoms and requested his COHb be repeated. The repeat COHb was 17% (84 minutes after the first). After three hours of oxygen, his COHb was 7%. In the final case, an 83-year-old non-smoking male presented to an ED with breathlessness and tachypnea and was diagnosed with COVID-19 pneumonia. His COHb was 7.1%, but he reported living in an all-electric home. Another adult who lived with him and rode with him to the ED was asymptomatic and had a COHb of 3%. Later, COHb of 1.9% was measured from blood collected at ED arrival, and gas chromatography/mass spectrometry confirmed this result (2%). Conclusions: COHb levels are not always accurate. Clinicians should use clinical judgment to manage their patients, including rejecting laboratory values that do not fit the clinical situation.