The public health impact of Paxlovid COVID-19 treatment in the United States (preprint)

The antiviral drug Paxlovid has been shown to rapidly reduce viral load. Coupled with vaccination, timely administration of safe and effective antivirals could provide a path towards managing COVID-19 without restrictive non-pharmaceutical measures. Here, we estimate the population-level impacts of expanding treatment with Paxlovid in the US using a multi-scale mathematical model of SARS-CoV-2 transmission that incorporates the within-host viral load dynamics of the Omicron variant. We find that, under a low transmission scenario (Re~1.2) treating 20% of symptomatic cases with Paxlovid would be life and cost saving, leading to an estimated 0.26 (95% CrI:0.03, 0.59) million hospitalizations averted, 30.61 (95% CrI:1.69, 71.15) thousand deaths averted, and US$52.16 (95% CrI:2.62, 122.63) billion reduction in the US. Rapid and broad use of the antiviral Paxlovid could substantially reduce COVID-19 morbidity and mortality, while averting socioeconomic hardship.

Global seasonal activities of respiratory syncytial virus before the COVID-19 pandemic: a systematic review (preprint)

Background: Varied seasonal patterns of respiratory syncytial virus (RSV) have been reported worldwide. We aimed to review the patterns of RSV activity globally before the COVID-19 pandemic and to explore factors potentially associated with RSV seasonality. Methods: We conducted a systematic review on articles identified in PubMed reporting RSV seasonality based on data collected before 1 January 2020. Information on the timing of the start, peak, and end of an RSV season, study location, study period, and details in study methods were extracted. RSV seasonal patterns were examined by geographic location, calendar month, analytic method and meteorological factors including temperature and absolute humidity. Correlation and regression analyses were conducted to explore the relationship between RSV seasonality and study methods and characteristics of study locations. Results: RSV seasons were reported in 209 articles published in 1973-2023 for 317 locations in 77 countries. Variations were identified in types of data, data collection and analytical methods across the studies. Regular RSV seasons were similarly reported in countries in temperate regions, with highly variable seasons identified in subtropical and tropical countries. Durations of RSV seasons were relatively longer in subtropical and tropical regions than from temperate regions. Longer durations of RSV seasons were associated with a higher daily average mean temperature and daily average mean absolute humidity. Conclusions: The global seasonal patterns of RSV provided important information for optimizing interventions against RSV infection. Heterogeneity in study methods highlighted the importance of developing and applying standardized approaches in RSV surveillance and data reporting.

The impact of COVID-19 on the employment status and psychological expectations of college graduates: Empirical evidence from the survey data of Chinese recruitment websites

Based on the big data and survey data of online recruitment platform, this paper empirically tests the impact of COVID-19 on the employment status and psychological expectations of college graduates. The results show that: under the impact of COVID-19 epidemic, both supply and demand sides of college graduates’ employment market are affected, such as the decline of recruitment demand, the rise of the employment supply, and the obvious decrease of employment market prosperity. The impacts of COVID-19 epidemic on college graduates’ employment status and psychological expectation in different cities are heterogeneous. In the short term, the epidemic has a negative impact on the employment of graduates, but the employment situation is gradually improving with the support of national policies. Under the influence of COVID-19 epidemic, graduates will change their employment location and expected salary, and they tend to choose “temporary non-employment,” and their proportions of getting offers and signing contracts are significantly reduced. This paper suggests: Firstly, we should continue to push forward the action plan of “expanding jobs in graduation season to promote employment,” and strengthen the persistence and permanence of employment promotion policies for college graduates;Secondly, encourage college students to change their employment concept and rationally adjust their employment expectations;Thirdly, to promote the development of flexible employment of college graduates, it is necessary to strengthen the propaganda of flexible employment, so that students can understand relevant policies;Fourthly, strengthen employment guidance services for graduates from poor families to ensure the continuity and stability of employment assistance policies.

Characterizing human collective behaviours of COVID-19 in Hong Kong (preprint)

People are likely to engage in collective behaviour online during extreme events, such as the COVID-19 crisis, to express their awareness, actions and concerns. Hong Kong has implemented stringent public health and social measures (PHSMs) to curb COVID-19 epidemic waves since the first COVID-19 case was confirmed on 22 January 2020. People are likely to engage in collective behaviour online during extreme events, such as the COVID-19 crisis, to express their awareness, actions and concerns. Here, we offer a framework to evaluate interactions among individuals emotions, perception, and online behaviours in Hong Kong during the first two waves (February to June 2020) and found a strong correlation between online behaviours of Google search and the real-time reproduction numbers. To validate the model output of risk perception, we conducted 10 rounds of cross-sectional telephone surveys from February 1 through June 20 in 2020 to quantify risk perception levels over time. Compared with the survey results, the estimates of the risk perception of individuals using our network-based mechanistic model capture 80% of the trend of people risk perception (individuals who worried about being infected) during the studied period. We may need to reinvigorate the public by engaging people as part of the solution to live their lives with reduced risk.

Predictive efficacies of vaccine dose fractionation using neutralizing antibody levels (preprint)

Background With the emergence of SARS-CoV-2 variants that eluded immunity from vaccines and prior infections, vaccine shortages and their effectiveness pose unprecedented challenges for governments to expand booster vaccination programs. Fractionation of vaccine doses might be an effective strategy to help society to face these challenges, which may have comparable efficacies in contrast with the standard doses. Methods In this study, we analyzed the relationship between in-vitro neutralization levels and the observed efficacies against asymptomatic and symptomatic infection of ten types of COVID-19 vaccines using data from 13 studies from vaccination and convalescent cohorts. We further projected efficacies for fractional doses based on 51 studies included in our systematic review. Results By comparing with the convalescent level, vaccine efficacy increases from 8.8% (95% CI: 1.4%, 16.1%) to 71.8% (95% CI: 63.0%, 80.7%) against asymptomatic infection, and from 33.6% (95% CI: 23.6%, 43.6%) to 98.6% (95% CI: 97.6%, 99.7%) against symptomatic infection, respectively, along with the mean neutralization level from 0.1 to 10 folds of convalescent level. And mRNA vaccines provide the strongest protection, and decrease slowly for fractional dosing between 50% and 100% dosage. Conclusions Our results are consistent with studies for immune protection from COVID-19 infection. Based on our study, we expect that fractional dose vaccination could provide a partial immunity for SARS-CoV-2 virus. Fractional doses of vaccines could be a viable vaccination strategy compared to full-dose vaccination and deserves further exploration. Key points We analyzed the relationship between neutralization levels and efficacies against asymptomatic and symptomatic infection of ten types of COVID-19 vaccines from convalescent cohorts. Fractional doses of vaccines could be a viable strategy compared to full-dose vaccination and deserves further exploration.

Acceptance and Attitude towards the Traditional Chinese Medicine among Asymptomatic COVID-19 Patients: A cross-sectional study in Shanghai Fangcang hospital (preprint)

Objective The Coronavirus Disease 2019 (COVID-19) has brought severe damage to global health and socioeconomics. In China, traditional Chinese medicine (TCM) is the most important complementary and alternative medicine (CAM) and it has shown a beneficial role in the prevention and treatment of COVID-19. However, it is unknown whether patients are willing to accept TCM treatment. The objective of our study is to investigate the acceptance, attitude, and independent predictors of TCM among asymptomatic COVID-19 patients admitted to Shanghai fangcang hospital during the outbreak of the COVID-19 pandemic in Shanghai in 2022.Methods A cross-sectional study was conducted on asymptomatic COVID-19 patients in the largest fangcang hospital in Shanghai, China, from April 22, 2022, to May 25, 2022. Based on the literature review of previous similar studies, a self-report questionnaire was developed to assess the patients’ attitude and acceptance of TCM, and a multivariate logistic regression analysis was conducted to determine the independent predictors of TCM acceptance.Results A total of 1,121 patients completed the survey, of whom 91.53% were willing to accept CAM treatment whereas 8.65% of participants showed no willingness. Among those who were positive to receive CAM treatment, 70.51% of the participants were willing to be treated with Chinese herbal medicine, 62.79% with Chinese patent medicine, 34.96% with massage therapy, 33.20% with moxibustion treatment, and 29.00% with cupping therapy. There were significant differences in the 10 variables such as monthly income level, SARS-CoV-2 vaccination, and patients' cognition and attitude towards TCM among the patients who were willing or unwilling to accept TCM treatment. Multivariate logistic regression analysis revealed that the patients who have received two doses of COVID-19 vaccine (OR = 2.069, 95%CI: 1.029–4.162, P = 0.041 vs not received), understood the culture of TCM (OR = 2.293, 95%CI: 1.029–4.162, P = 0.014 vs not understood), thought TCM needs a longer time to exert efficacy (OR = 1.607, 95%CI: 0.849–3.034, P = 0.145 vs not thought), thought the treatment of TCM is safe (OR = 2.856, 95%CI: 1.334–6.112, P = 0.007 vs not thought), thought the treatment of TCM is effective (OR = 2.724, 95%CI: 1.249–5.940, P = 0.012 vs not thought), and those who informed their attending physician if using TCM for treatment (OR = 3.455, 95%CI:1.867–6.392, P < 0.001 vs not informed) were more likely to accept TCM treatment. However, patients who thought TCM might delay your treatment (OR = 0.256, 95%CI: 0.142–0.462, P < 0.001 not thought) was an independent predictor for unwillingness to accept TCM treatment.Conclusion This is the first study to investigate the acceptance, attitude, and predictors of intention to receive TCM among asymptomatic COVID-19 patients. The next step of this study will be a long-term follow-up of these patients to observe whether accepting TCM treatment will influence their quality of life.

The risk of SARS-CoV-2 Omicron variant emergence in low and middle-income countries (LMICs) (preprint)

We estimated the probability of undetected emergence of the SARS-CoV-2 Omicron variant in 25 low and middle-income countries (LMICs) prior to December 5, 2021. In nine countries, the risk exceeds 50%; in Turkey, Pakistan and the Philippines, it exceeds 99%. Risks are generally lower in the Americas than Europe or Asia.

Superspreading of SARS-CoV-2 infections: A Systematic Review and Meta-analysis (preprint)

Superspreading in transmission is a feature of SARS-CoV-2 transmission. We conducted a systematic review and meta-analysis on globally reported dispersion parameters of SARS-CoV-2. The pooled estimate was 0.55 (95% CI: 0.30, 0.79). The study location and method were found to be important drivers for its diversity.

International risk of SARS-CoV-2 Omicron variant importations originating in South Africa (preprint)

Omicron, a fast-spreading SARS-CoV-2 variant of concern reported to the World Health Organization on November 24, 2021, has raised international alarm. We estimated there is at least 50% chance that Omicron had been introduced by travelers from South Africa into all of the 30 countries studied by November 27, 2021.

Targeting the catecholamine-cytokine axis to prevent SARS-CoV-2 cytokine storm syndrome (preprint)

The mortality of Coronavirus disease 2019 (COVID-19) appears to be driven by acute respiratory distress syndrome (ARDS) and a dysregulated immune response to SARS-CoV-2. Emerging evidence suggests that a subset of COVID-19 is characterized by the development of a cytokine storm syndrome (CSS), and interleukin (IL)-6 levels are predictors of COVID-19 severity and in-hospital mortality. Targeting hyper-inflammation in COVID-19 may be critical for reducing mortality. Catecholamines enhance inflammatory injury by augmenting the production of IL-6 and other cytokines through a self-amplifying feed-forward loop in immune cells that requires alpha-1 adrenergic receptor (1-AR) signaling. Prophylactic inhibition of catecholamine synthesis with the 1-AR antagonist prazosin reduced catecholamines and cytokine responses in mice, and resulted in markedly increased survival following various hyper-inflammatory stimuli. These findings offer a rationale for studying 1-AR antagonists in the prophylaxis of patients with COVID-19-CSS and ARDS. As high infection rates threaten to overwhelm hospital capacity during this pandemic, preventative approaches that ameliorate COVID-19 severity and reduce excessive mortality are desperately needed. We hypothesize that treatment with prazosin of individuals who test positive for SARS-CoV-2 could reduce catecholamine surges, secondary cytokine dysregulation, and mortality. To investigate a potential role for 1-AR antagonists in preventing poor outcomes in ARDS, we conducted a retrospective analysis of hospitalized patients diagnosed with ARDS. Using data from the Truven Health MarketScan Research Database (2010-2017), we identified 13,125 men (age 45-64) with ARDS, of whom 655 patients (5.0%) were prescribed 1-AR antagonists in the previous year. Applying logistic regression models, we found that patients with prior use of 1-AR antagonists had lower odds of invasive mechanical ventilation compared to non-users (adjusted OR=0.75, 95% CI 0.59-0.95, p=0.019). Perhaps more importantly, those patients had a ~36% lower incidence of both being ventilated and dying in the hospital (adjusted OR=0.59, 95% CI 0.34-0.95, p=0.042). By contrast, prior use of beta-adrenergic receptor ({beta}-AR) antagonists was not correlated with either outcome. We extended these analyses to patients admitted with pneumonia. Of 108,956 subjects in this cohort, 5,498 patients (5.0%) were taking 1-AR antagonist. Similar to ARDS, patients with pneumonia on 1-AR antagonists (but no {beta}-AR antagonists) had a lower odds of mechanical ventilation (adjusted OR=0.83, 95% CI 0.75-0.92, p<0.001) and of both being ventilated and dying in the hospital (adjusted OR=0.77, 95% CI 0.62-0.94, p=0.014) compared to non-users. Mirroring findings from pre-clinical models, these data support a clinical rationale to study 1-AR antagonists in the prevention of severe complications of pneumonia, ARDS, and COVID-19. Prospective, randomized clinical trials of alpha-1 receptor antagonists (e.g. prazosin) administered prior to the onset of severe symptoms are needed to assess their efficacy in preventing CSS and reducing mortality in COVID-19.

Incidence, clinical characteristics and prognostic factor of patients with COVID-19: a systematic review and meta-analysis (preprint)

Background: Recently, Coronavirus Disease 2019 (COVID-19) outbreak started in Wuhan, China. Although the clinical features of COVID-19 have been reported previously, data regarding the risk factors associated with the clinical outcomes are lacking. Objectives: To summary and analyze the clinical characteristics and identify the predictors of disease severity and mortality. Methods: The PubMed, Web of Science Core Collection, Embase, Cochrane and MedRxiv databases were searched through February 25, 2020. Meta-analysis of Observational Studies in Epidemiology (MOOSE) recommendations were followed. We extracted and pooled data using random-effects meta-analysis to summary the clinical feature of the confirmed COVID-19 patients, and further identify risk factors for disease severity and death. Heterogeneity was evaluated using the I2 method and explained with subgroup analysis and meta-regression. Results: A total of 30 studies including 53000 patients with COVID-19 were included in this study, the mean age was 49.8 years (95% CI, 47.5-52.2 yrs) and 55.5% were male. The pooled incidence of severity and mortality were 20.2% (95% CI, 15.1-25.2%) and 3.1% (95% CI, 1.9-4.2%), respectively. The predictor for disease severity included old age ([≥] 50 yrs, odds ratio [OR] = 2.61; 95% CI, 2.29-2.98), male (OR =1.348, 95% CI, 1.195-1.521), smoking (OR =1.734, 95% CI, 1.146-2.626) and any comorbidity (OR = 2.635, 95% CI, 2.098-3.309), especially chronic kidney disease (CKD, OR = 6.017; 95% CI, 2.192-16.514), chronic obstructive pulmonary disease (COPD, OR = 5.323; 95% CI, 2.613-10.847) and cerebrovascular disease (OR = 3.219; 95% CI, 1.486-6.972). In terms of laboratory results, increased lactate dehydrogenase (LDH), C-reactive protein (CRP) and D-dimer and decreased blood platelet and lymphocytes count were highly associated with severe COVID-19 (all for P < 0.001). Meanwhile, old age ([≥] 60 yrs, RR = 9.45; 95% CI, 8.09-11.04), followed by cardiovascular disease (RR = 6.75; 95% CI, 5.40-8.43) hypertension (RR = 4.48; 95% CI, 3.69-5.45) and diabetes (RR = 4.43; 95% CI, 3.49-5.61) were found to be independent prognostic factors for the COVID-19 related death. Conclusions: To our knowledge, this is the first evidence-based medicine research to explore the risk factors of prognosis in patients with COVID-19, which is helpful to identify early-stage patients with poor prognosis and adapt effective treatment.