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1.
Preprint in English | medRxiv | ID: ppmedrxiv-22275610

ABSTRACT

Alaska is a unique US state because of its large size, geographically disparate population density, and physical distance from the contiguous United States. Here, we describe a pattern of SARS-CoV-2 variant emergence across Alaska reflective of these differences. Using genomic data, we found that in Alaska the Omicron sublineage BA.2.3 overtook BA.1.1 by the week of 2022-02-27, reaching 48.5% of sequenced cases. On the contrary in the contiguous United States, BA.1.1 dominated cases for longer, eventually being displaced by BA.2 sublineages other than BA.2.3. BA.2.3 only reached a prevalence of 10.9% in the contiguous United States. Using phylogenetics, we found evidence of potential origins of the two major clades of BA.2.3 in Alaska and with logistic regression estimated how it emerged and spread throughout the state. The combined evidence is suggestive of founder events in Alaska and is reflective of how Alaskas unique dynamics influence the emergence of SARS-CoV-2 variants.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-22272446

ABSTRACT

Alaska is the largest geographic state in the United States with the lowest population density and a mix of urban centers and isolated rural communities. The differences in population dynamics in Alaska from the contiguous United States may have contributed to a unique pattern of emergence and spread of SARS-CoV-2 variants observed in early 2021. Here we examined 2,323 virus genomes from Alaska and 278,635 virus genomes from the contiguous United States collected between the first week of December 2020 through the last week of June 2021. We focused on this timeframe because of the notable emergence and spread of the SARS-CoV-2 lineage B.1.1.519 observed in Alaska. We found that this variant was consistently detected in Alaska from the end of January through June of 2021 with a peak prevalence in April of 77.9% unlike the rest of the United States with a peak prevalence of 4.6%. In Alaska, the earlier emergence of B.1.1.519 coincided with a later peak of Alpha (B.1.1.7) when compared to the rest of the United States. We also observed differences in the composition of lineages and variants over time between the two most populated regions of Alaska. Although there was a modest increase in COVID-19 cases during the peak incidence of B.1.1.519, it is difficult to disentangle how social dynamics conflated changes in COVID-19 during this time. We suggest that the viral characteristics, such as amino acid substitutions in the spike protein, and a founder effect likely contributed to the unique spread of B.1.1.519 in Alaska.

3.
Preprint in English | medRxiv | ID: ppmedrxiv-20078964

ABSTRACT

IntroductionCloth face coverings and surgical masks have become commonplace across the United States in response to the SARS-CoV-2 epidemic. While evidence suggests masks help curb the spread of respiratory pathogens, research is limited. Face masks have quickly become a topic of public debate as government mandates have started requiring their use. Here we investigate the association between self-reported mask wearing, social distancing and community SARS-CoV-2 transmission in the United States, as well as the effect of statewide mandates on mask uptake. MethodsSerial cross-sectional surveys were administered June 3 through July 27, 2020 via web platform. Surveys queried individuals likelihood to wear a face mask to the grocery store or with family and friends. Responses (N=378,207) were aggregated by week and state and combined with measures of the instantaneous reproductive number (Rt), social distancing proxies, respondent demographics and other potential sources of confounding. We fit multivariate logistic regression models to estimate the association between mask wearing and community transmission control (Rt <1) for each state and week. Multiple sensitivity analyses were considered to corroborate findings across mask wearing definitions, Rt estimators and data sources. Additionally, mask wearing in 12 states was evaluated two weeks before and after statewide mandates. ResultsWe find an upward trend in mask usage across the U.S., although uptake varies by geography and demographic groups. A multivariate logistic model controlling for social distancing and other variables found a 10% increase in mask wearing was associated with a 3.53 (95% CI: 2.03, 6.43) odds of transmission control (Rt <1). We also find that communities with high mask wearing and social distancing have the highest predicted probability of a controlled epidemic. These positive associations were maintained across sensitivity analyses. Segmented regression analysis of mask wearing found no statistical change following mandates, however the positive trend of increased mask wearing over time was preserved. ConclusionWidespread utilization of face masks combined with social distancing increases the odds of SARS-CoV-2 transmission control. Mask wearing rose separately from government mask mandates, suggesting supplemental public health interventions are needed to maximize mask adoption and disrupt the spread of SARS-CoV-2, especially as social distancing measures are relaxed.

4.
Preprint in English | medRxiv | ID: ppmedrxiv-20120808

ABSTRACT

BackgroundSo far, there has been no published population study on the relationship between COVID-19 infection and publics risk perception, information source, knowledge, attitude and four non-pharmaceutical interventions(NPI: hand washing, proper coughing habits, social distancing and mask wearing) during the COVID-19 outbreak in China. MethodsAn online survey of 8158 Chinese adults between 22 February to 5 March 2020 was conducted. Bivariate associations between categorical variables were examined using Fisher exact test. We also explored the determinants of four NPIs as well as their association with COVID-19 infection using logistic regression. ResultsOf 8158 adults included, 57 (0.73%) were infected with COVID-19. The overwhelming majority of respondents showed a positive attitude (99.2%), positive risk perception (99.9%) and high knowledge levels that were among the strongest predictors of four highly adopted NPIs (hand washing:96.8%; proper coughing: 93.1%; social distancing:87.1%; mask wearing:97.9%). There was an increased risk of COVID-19 infection for those who not washing hands (2.28% vs 0.65%; RR=3.53: 95%CI: 1.53-8.15; P<0.009); not practicing proper coughing (1.79% vs 0.73%; RR=2.44: 95%CI: 1.15-5.15;P=0.026); not practicing social distancing (1.52% vs 0.58%; RR=2.63:95%CI:1.48 - 4.67; P=0.002); and not wearing a mask (7.41% vs 0.6%; RR=12.38:95%CI:5.81-26.36; P<0.001). For those who did practice all other three NPIs, wearing mask was associated with significantly reduced risk of infection compared to those who did not wear a mask (0.6% vs 16.7%; p=0.035). Similarly, for those who did not practice all or part of the other three NPIs, wearing mask was also associated with significantly reduced risk of infection. In a penalised logistic regression model including all four NPIs, wearing a mask was the only significant predictor of COVID-19 infection among four NPIs (OR=7.20; 95%CI:2.24-23.11; p<0.001). ConclusionsWe found high levels of risk perception, positive attitude, desirable knowledge as well as a high level of adopting four NPIs. The relevant knowledge, risk perception and attitude were strong predictors of adapting the four NPIs. Mask wearing, among four personal NPIs, was the most effective protective measure against COVID-19 infection with added preventive effect among those who practised all or part of the other three NPIs.

5.
Chinese Medical Journal ; (24): 4249-4253, 2012.
Article in English | WPRIM (Western Pacific) | ID: wpr-339862

ABSTRACT

<p><b>BACKGROUND</b>The correlation between angiographic or intravascular ultrasound (IVUS) variables and fractional flow reserve (FFR) in patients with single left anterior descending artery (LAD) lesion has not been studied. The current study aimed at determining the best cutoff value of angiographic and IVUS parameters for defining FFR < 0.80 in patients with LAD lesion.</p><p><b>METHODS</b>Quantitative coronary analysis, IVUS and FFR measurements were undergone in 169 patients with single LAD lesion. The best angiographic and IVUS cutoff value and their predictive value for FFR < 0.80 were compared using area under the receiver-operator characteristic curve (AUC) in overall patients or in subgroups stratified by lesion sites.</p><p><b>RESULTS</b>FFR < 0.80 was found in 99 lesions (58.6%). Minimal lumen area (MLA), and plaque burden (PB) were two predictors of FFR < 0.80. Lesion length had less value in predicting FFR < 0.80. The cutoff value of PB and MLA for FFR < 0.80 was 75.4% and 3.03 mm(2). MLA and PB had similar high diagnostic value for proximal (cutoff value 3.04 mm(2) and 76.5%) and distal LAD lesion (2.82 mm(2) and 80.6%). Combination of MLA (2.82 mm(2)) and PB (80.6%) had increased diagnostic value for distal LAD lesion.</p><p><b>CONCLUSIONS</b>MLA and plaque burden had equivalent diagnostic value for FFR < 0.80 when lesion localized in LAD. The predictive value of combination of MLA and plaque burden for distal LAD lesion was strengthened.</p>


Subject(s)
Female , Humans , Male , Middle Aged , Coronary Angiography , Methods , Coronary Artery Disease , Diagnostic Imaging , Coronary Vessels , Diagnostic Imaging , Plaque, Atherosclerotic , Diagnostic Imaging , Ultrasonography, Interventional , Methods
6.
Chinese Medical Journal ; (24): 2086-2091, 2009.
Article in English | WPRIM (Western Pacific) | ID: wpr-240834

ABSTRACT

<p><b>BACKGROUND</b>The mechanisms responsible for the occurrence of a kissing unsatisfied (KUS) result after classical crush stenting remain unclear. The present study aimed at analyzing the mechanisms and clinical significance of KUS.</p><p><b>METHODS</b>Two hundred and thirteen patients with true bifurcation lesions treated with classical crush stenting and final kissing balloon inflation (FKBI) were assigned to upper, middle, and lower groups according to the position of the side branch re-wiring assessed by visual estimation, quantitative coronary analysis (QCA) and intravascular ultrasound (IVUS). Angiographic follow-up was indexed at 12 months.</p><p><b>RESULTS</b>The upper group was characterized by a larger bifurcation angle of 55.53 degrees +/- 25.25 degrees (P = 0.030) and a longer procedural time (42.43 +/- 23.92) minutes (P = 0.015). The overall rate of KUS by visual estimation was 10.48%, with 5.4% in the upper group, 3.9% in middle group, and 36.1% in lower group (P < 0.001). For the diagnosis of KUS, visual inspection demonstrated a good correlation with both QCA and IVUS. Smaller stent diameter was the main reason for KUS in the upper group, while extra-stent side wire location, or re-wire in a low position was the main mechanism attributed to KUS in the lower group. The Lower group had more restenosis, with most restenotic lesions at a lower position of the side branch ostium. KUS (HR 1.652, 95% CI 1.332 - 2.088, P < 0.001) and re-wiring position (HR 2.341, 95% CI 1.780 - 4.329, P < 0.001) were two independent predictors of side branch restenosis. Re-wiring position (OR 0.458, 95%CI 0.336 - 0.874, P = 0.001) and side stent expansion (OR 3.122, 95%CI 2.883 - 5.061, P = 0.014) were factors predicting the findings of KUS.</p><p><b>CONCLUSIONS</b>Side wire outside side stents resulted in more KUS and restenosis. Different restenotic lesion types reflected individual mechanisms contributing to the development of plaque proliferation.</p>


Subject(s)
Aged , Female , Humans , Male , Middle Aged , Angioplasty, Balloon, Coronary , Methods , Coronary Disease , Therapeutics , Stents , Treatment Outcome
7.
Chinese Medical Journal ; (24): 2278-2285, 2009.
Article in English | WPRIM (Western Pacific) | ID: wpr-307798

ABSTRACT

<p><b>BACKGROUND</b>The safety of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) lesions in remote hospitals without surgical facilities remains unknown. This study aimed to evaluate three-year outcomes after CTO for PCI in ten centers around China where no on-site coronary artery bypass grafting (CABG) support was available.</p><p><b>METHODS</b>A total of 152 patients from 10 Chinese hospitals without on-site surgical facilities were prospectively studied. Intra-procedural and in-hospital events were assessed. Angiographic follow-up was indexed eight months after the initial procedure. Clinical follow-up was extended to three years. The primary outcome was the rate of major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction and target-vessel revascularization (TVR).</p><p><b>RESULTS</b>The incidence of CTO was 7.9% in patients who underwent PCI. Successful recanalization was achieved in 132 patients (86.8%). Compared with patients in the PCI success group, patients with PCI procedural failure had longer lesion lengths ((42.32 +/- 22.08) mm vs (27.61 +/- 22.85) mm, P = 0.023), a higher rate of perforation (25.0% vs 0, P = 0.014), and a greater need for pericardial puncture. There were significant differences in MACE in-hospital and at one year and three years between the failure (10.0%, 30.0% and 35.0%) and the success (3.0%, 12.1% and 14.4%) groups (P = 0.037, 0.034 and 0.040, respectively). These led to a significant decrease in the MACE-free survival rate at one and three years in the failure group, compared with the success group (P = 0.031 and 0.023, respectively). Stump was the only predictor of recanalization success (HR 0.158, 95% CI 0.041-0.612, P = 0.008), whereas procedural failure (OR 13.023, 95% CI 6.67-13.69, P = 0.002), incomplete revascularization (OR 9.71, 95% CI 2.93-5.59, P = 0.005), and total stent length (OR 6.02, 95% CI 1.55-11.93, P = 0.027) were three independent predictors of MACE.</p><p><b>CONCLUSIONS</b>PCI for CTO was unsafe in remote hospitals without CABG facilities. Paying attention to coronary perforation is important for successful procedures.</p>


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Angioplasty, Balloon, Coronary , Chronic Disease , Coronary Artery Bypass , Coronary Stenosis , Epidemiology , Therapeutics , Survival Rate , Treatment Outcome
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