Billions of doses of COVID-19 vaccines have been administered globally, dramatically reducing SARS-CoV-2 incidence and severity in some settings. Many studies suggest vaccines provide a high degree of protection against infection and disease, but precise estimates vary and studies differ in design, outcomes measured, dosing regime, location, and circulating virus strains. Here we conduct a systematic review of COVID-19 vaccines through February 2022. We included efficacy data from Phase 3 clinical trials for 15 vaccines undergoing WHO Emergency Use Listing evaluation and real-world effectiveness for 8 vaccines with observational studies meeting inclusion criteria. Vaccine metrics collected include protection against asymptomatic infection, any infection, symptomatic COVID-19, and severe outcomes including hospitalization and death, for partial or complete vaccination, and against variants of concern Alpha, Beta, Gamma, Delta, and Omicron. We additionally review the epidemiological principles behind the design and interpretation of vaccine efficacy and effectiveness studies, including important sources of heterogeneity.

Despite antiretroviral therapy, chronic lung diseases remain an important source of morbidity and mortality in people with HIV (PWH). We sought to identify clinical and immunological markers of pulmonary impairment among PWH in India. Two hundred ten adult PWH receiving antiretroviral therapy (ART) were prospectively evaluated for 3 years. Plasma concentrations of interleukin (IL)-6, IL-10, tumor necrosis factor alpha, D-dimer, C-reactive protein, soluble (s)CD14, and sCD163 were measured at enrollment. We used multivariable linear and logistic regression to measure the association of baseline and time-varying clinical and immunological variables with spirometry-defined chronic obstructive pulmonary disease (COPD), restrictive spirometry pattern (RSP), preserved ratio impaired spirometry (PRISm), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC) during the third year of follow-up. After adjusting confounders, females were 7 times more likely to have RSP (95% CI, 2.81 to 17.62; P < .001) and 22 times more likely to have PRISm (95% CI, 7.42 to 69.92; P < .001) compared with men. Higher IL-6 concentrations were associated with lower FEV1 z-scores (β, −0.14 per log-higher; 95% CI, −0.29 to 0.008; P = .06) and higher odds of COPD (adjusted odds ratio [aOR], 2.66 per log-higher; 95% CI, 1.16 to 6.09; P = .02). Higher D-dimer concentrations were associated with lower FVC z-scores (β, −0.40 per log-higher; 95% CI, −0.78 to −0.01; P = .04). Conversely, higher IL-10 concentrations were associated with lower odds of PRISm (aOR, 0.76 per log-higher; 95% CI, 0.59 to 0.99; P = .04). Female sex, higher concentrations of IL-6 and D-dimer, and lower concentrations of IL-10 were associated with pulmonary impairment in adult PWH receiving ART in India.

Background: Predictors of morbidity and mortality in hospitalized COVID-19 patients have been extensively studied. However, comparative analyses of predictors for hospitalization versus discharge from the emergency department remain limited. Methods: This retrospective study evaluated predictors of hospitalization among adults (≥18 years) presenting to the emergency department with COVID-19 infection between 1 March 2020 and 15 June 2020. Data were obtained from electronic health records across five hospitals within the Johns Hopkins Health System, encompassing 2513 beds. Multivariable logistic regression models were employed to assess the association between sociodemographic characteristics, clinical symptoms, and comorbidities with hospitalization. Results: Of the 2767 patients presenting to the emergency department, 1678 (61%) were hospitalized, while 1089 (39%) were discharged from the emergency department. Hospitalized patients were older (mean age 61.8 years, SD 18), more likely to be African American and White, non-Hispanic, unemployed or on disability, medically insured, had access to primary care, and presented on weekends. Smoking status, alcohol use, and higher comorbidity burden (mean age-adjusted Charlson Comorbidity Index > 3) were also more prevalent with hospitalization. Dyspnea was a prominent clinical feature among hospitalized patients. After adjusting for sociodemographic and clinical risk factors, significant predictors of hospitalization included health insurance (OR 3.44; 95% CI: 1.98–6), having a primary care (OR 1.85; 95% CI: 1.33–2.59), presentation from a non-home locale (OR 4.04; 95% CI: 1.93–8.47), age-adjusted CCI > 3 (OR 1.72; 95% CI: 1.11–2.68), dyspnea (OR 2.22; 95% CI: 1.56–3.17), neutrophil-to-lymphocyte ratio ≥ 3 (OR 2.17; 95% CI: 1.54–3.06), and an abnormal chest radiograph findings (OR 6.17; 95% CI: 4.40–8.66). Interestingly, obesity, defined as a BMI ≥ 30 kg/m² (OR 0.45; 95% CI: 0.32–0.64), and the presence of fever (OR 0.64; 95% CI: 0.43–0.95) were found to be associated with a decreased likelihood of hospitalization. Conclusions: Future studies are warranted to further explore predictors of COVID-19 hospitalization, with particular focus on the implications of weekend presentations and the paradoxical relationship of obesity with COVID-19 health outcomes. These findings could inform the development of triage models to enhance preparedness for future pandemics.

Background: Spectrum of COVID-19 disease ranges from asymptomatic or mild symptomatic to life threatening cases. Population based sero-epidemiological studies are useful for assessing the magnitude of COVID-19 infection in a geographic area and it is helpful for planning control measures. Objectives: To estimate the sero-prevalence of SARS CoV-2 antibody in the general population of Tripura and to study the factors associated with it. Methodology: This community based cross-sectional study was conducted from 15th October to 14th November 2020 among 4800 subjects selected from the whole state of Tripura, India by probability proportionate to size sampling technique using 30 clusters. Electrochemiluminescence (eCLIA) based assay was used to test the serum samples for SARS-CoV-2 specific antibody. Data entry and analysis was performed using SPSS-25 for windows and sero-prevalence was expressed in percentages. Binary logistic regression model was used for predicting sero-positivity by including the significant factors associated with SARS-CoV-2 infection as found out by univariate analysis. Result: Sero-prevalence of SARS-CoV-2 antibody was found to be 34% among the general population of Tripura and it varied from 42.4% to 19.7% across different districts. Logistic regression model has identified, urban residency (OR: 1.21, 95% CI: 1.03-1.42), ethnic community (OR: 0.55, 95% CI: 0.48-0.64) and literacy (OR: 1.41, 95% CI: 1.13-1.77) as the independent risk factors for SARS-CoV-2 sero-positivity (p<0.05). Conclusion: Approximately one out of three residents of Tripura has already acquired the novel SARS CoV-2 infection. As the threshold required for achieving herd immunity against COVID-19 is not yet known, control measures need to be continued for preventing further spread of disease in the community.