Change in covid-19 risk over time following vaccination with CoronaVac: test negative case-control study

Confronting Health Misinformation Surrounding COVID-19 Vaccines in the State of Florida

COVID-19 vaccination is estimated to have averted more than 2.4 million deaths globally. In the United States (U.S.) alone, more than 120,000 deaths and 700,000 hospitalizations are reportedly estimated to have been prevented during the first six months of the vaccine campaign. Despite the overwhelming evidence regarding the safety and efficacy of vaccination, COVID-19 vaccine hesitancy continues to pose a significant threat to public health. Notably, an unexpected source of vaccine misinformation has been the Surgeon General of the State of Florida, Dr. Joseph Ladapo. While both a tenured faculty member of the University of Florida, College of Medicine and the Surgeon General of Florida, Dr. Ladapo has delivered official Florida Department of Health statements regarding COVID-19 vaccines that run contrary to those of the U.S. Centers for Disease Control and Prevention (CDC). While tenure is designed to protect those with contrarian views, we believe that the University has an ethical obligation to condemn misleading statements that put public health at risk. Herein, we explore the challenges of managing misinformation disseminated by someone who is simultaneously a tenured professor at a public, state-supported university, and a politically appointed public health official.

Association between cumulative exposure periods of flupentixol or any antipsychotics and risk of lung cancer

BACKGROUND

Preclinical evidence suggests that certain antipsychotic medications may inhibit the development of lung cancer. This study aims to investigate the association between incident lung cancer and different cumulative exposure periods of flupentixol or any antipsychotics.

METHODS

Using electronic health records from the Hospital Authority in Hong Kong, this nested case-control study included case participants aged 18 years or older with newly diagnosed lung cancer after initiating antipsychotics between January 1, 2003, and August 31, 2022. Each case was matched to up to ten controls of the same sex and age, who were also antipsychotic users. Multivariable conditional logistic regression models were conducted to quantify the association between lung cancer and different cumulative exposure times of flupentixol (0-365 days [ref]; 366-1825 days; 1826+ days) and any antipsychotics (1-365 days [ref]; 366-1825 days; 1826+ days), separately.

RESULTS

Here we show that among 6435 cases and 64,348 matched controls, 64.06% are males, and 52.98% are aged 65-84 years. Compared to patients with less than 365 days of exposure, those with 366-1825 days of exposure to flupentixol (OR = 0.65 [95% CI, 0.47-0.91]) and any antipsychotics (0.42 [0.38-0.45]) have a lower risk of lung cancer. A decreased risk is observed in patients who have 1826+ days of cumulative use of any antipsychotics (0.54 [0.47-0.60]).

CONCLUSIONS

A reduced risk of lung cancer is observed in patients with more than one year of exposure to flupentixol or any antipsychotics. Further research on the association between lung cancer and other antipsychotic agents is warranted.

Effectiveness of inactivated COVID-19 vaccines against SARS-CoV-2 infections among healthcare personnel in Pakistan: a test-negative case-control study

OBJECTIVE

During the COVID-19 pandemic, several vaccines that were efficacious in randomised controlled trials were authorised for mass vaccination. In developing countries, inactivated vaccines were widely administered. While inactivated vaccines have been deemed effective in reducing disease severity, for healthcare personnel (HCP), effectiveness against SARS-CoV-2 infections is essential to reduce the risk to vulnerable patients and ensure a stable healthcare workforce. There are limited studies examining inactivated vaccines' effectiveness against SARS-CoV-2 variants of concern (VOCs) in real-world settings. We estimated the effectiveness of inactivated vaccines (BBIBP-CorV and CoronaVac) against reverse transcription PCR (RT-PCR)-confirmed SARS-CoV-2 infections among HCP in the setting of emerging SARS-CoV-2 VOCs in Pakistan.

DESIGN

A retrospective matched, test-negative case-control analysis using existing data from an Employee Health database on HCP at a large, private healthcare system in Pakistan.

PARTICIPANTS

4599 HCP were tested between 1 April and 30 September 2021. Each case (PCR positive) was matched to two to six controls (PCR negative) by the date of the RT-PCR test (±7 days) to reduce bias.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was vaccine effectiveness (VE) against SARS-CoV-2 infection. The secondary outcome was VE against symptomatic SARS-CoV-2 infection. Per cent VE was calculated using (1-OR)*100, with the OR of getting a PCR-confirmed SARS-COV-2 infection estimated using conditional logistic regression, after adjusting for age, gender, work area and history of SARS-CoV-2 infection.

RESULTS

Inactivated vaccines were ineffective against SARS-CoV-2 infections after receiving the first dose (VE 17%, 95% CI -10, 39; p=0.261). They showed modest effectiveness ≥14 days after the second dose against SARS-CoV-2 infections (VE 30%, 95% CI 7, 48; p=0.015) and symptomatic SARS-CoV-2 infections (VE 33%, 95% CI 6, 52; p=0.002).

CONCLUSIONS

Inactivated vaccines show modest effectiveness against SARS-CoV-2 infections in the setting of emerging VOCs. This builds a strong case for boosters and/or additional vaccination.

The effectiveness of COVID-19 vaccination against all-cause mortality in patients with type 2 diabetes mellitus: the observation during the initial period of the cancellation of the "Dynamic Zero Policy" in mainland China

AIMS

This study aims to assess the effectiveness of COVID-19 vaccination against all-cause death in patients with type 2 diabetes mellitus (T2DM).

METHODS

Subjects were patients with T2DM who were administered by general practitioner (GP). Use electronic exchange platform to obtain the information on COVID-19 vaccination, all-cause deaths and risk factors. Logistic regression models were used to calculate the odd ratio (OR) and 95% CI for the association between COVID-19 vaccination and mortality. The vaccine effectiveness (VE) was calculated as (1- adjusted OR) ×100%.

RESULTS

A total of 27,156 subjects had 53.81%, 17.65%, and 23.43% coverage for the booster, full, and partial COVID-19 vaccination, reported 328 deaths and a mortality of 1.2%. The adjusted OR (95%CI) was 0.85(0.60-1.21) for those received partial vaccination, 0.31(0.22-0.43) for those received full vaccination, and 0.12(0.08-0.18) for those received booster vaccination, compared to the unvaccinated individuals. The VE (95%CI) was 88.00(82.30-91.80) of booster vaccination, 69.30(56.60-78.30) of full vaccination, and 17.60(-17.10-42.00) of partial vaccination.

CONCLUSION

COVID-19 vaccination could effectively prevent the all-cause death in patients with T2DM during the omicron variant outbreak period, after the cancellation of the "Dynamic Zero Policy" in mainland China.

Current Challenges With the Use of Test-Negative Designs for Modeling COVID-19 Vaccination and Outcomes

The widespread testing for severe acute respiratory syndrome coronavirus 2 infection has facilitated the use of test-negative designs (TNDs) for modeling coronavirus disease 2019 (COVID-19) vaccination and outcomes. Despite the comprehensive literature on TND, the use of TND in COVID-19 studies is relatively new and calls for robust design and analysis to adapt to a rapidly changing and dynamically evolving pandemic and to account for changes in testing and reporting practices. In this commentary, we aim to draw the attention of researchers to COVID-specific challenges in using TND as we are analyzing data amassed over more than two years of the pandemic. We first review when and why TND works and general challenges in TND studies presented in the literature. We then discuss COVID-specific challenges which have not received adequate acknowledgment but may add to the risk of invalid conclusions in TND studies of COVID-19.

Evaluation of COVID-19 vaccines in primary prevention against infections and reduction in severity of illness following the outbreak of SARS-CoV-2 omicron variant in Shanghai

Objectives

To evaluate COVID-19 vaccines in primary prevention against infections and lessen the severity of illness following the most recent outbreak of the SARS-CoV-2 Omicron variant in Shanghai.

Data sources

Data from 153,544 COVID-19 patients admitted to the Shanghai "Four-Leaf Clover" Fangcang makeshift shelter hospital were collected using a structured electronic questionnaire, which was then merged with electronic medical records of the hospital. For healthy controls, data on vaccination status and other information were obtained from 228 community-based residents, using the same structured electronic questionnaire.

Methods

To investigate whether inactivated vaccines were effective in protecting against SARS-CoV-2 virus, we estimated the odds ratio (OR) of the vaccination by comparing cases and matched community-based healthy controls. To evaluate the potential benefits of vaccination in lowering the risk of symptomatic infection (vs. asymptomatic), we estimated the relative risk (RR) of symptomatic infections among diagnosed patients. We also applied multivariate stepwise logistic regression analyses to measure the risk of disease severity (symptomatic vs. asymptomatic and moderate/severe vs. mild) in the COVID-19 patient cohort with vaccination status as an independent variable while controlling for potential confounding factors.

Results

Of the 153,544 COVID-19 patients included in the analysis, the mean age was 41.59 years and 90,830 were males (59.2%). Of the study cohort, 118,124 patients had been vaccinated (76.9%) and 143,225 were asymptomatic patients (93.3%). Of the 10,319 symptomatic patients, 10,031 (97.2%), 281 (2.7%), and 7 (0.1%) experienced mild, moderate, and severe infections, respectively. Hypertension (8.7%) and diabetes (3.0%) accounted for the majority of comorbidities. There is no evidence that the vaccination helped protect from infections (OR = 0.82, p = 0.613). Vaccination, however, offered a small but significant protection against symptomatic infections (RR = 0.92, p < 0.001) and halved the risk of moderate/severe infections (OR = 0.48, 95% CI: 0.37-0.61). Older age (≥60 years) and malignant tumors were significantly associated with moderate/severe infections.

Conclusion

Inactivated COVID-19 vaccines helped provide small but significant protection against symptomatic infections and halved the risk of moderate/severe illness among symptomatic patients. The vaccination was not effective in blocking the SARS-CoV-2 Omicron Variant community spread.

Neutralizing and Total/IgG Spike Antibody Responses Following Homologous CoronaVac vs. BNT162b2 Vaccination Up to 90 Days Post-Booster

INTRODUCTION

We documented the total spike antibody (S-Ab), IgG S-Ab and neutralizing antibody (N-Ab) responses of BNT162b2/CoronaVac vaccinees up to 90 days post-booster dose.

METHODS

We included 32 homologous regimen CoronaVac vaccinees and 136 BNT162b2 mRNA vaccinees. We tested their total S-Ab (Roche), IgG (Abbott) and N-Ab (Snibe) levels at set time points from January 2021 to April 2022. All subjects were deemed to be COVID-19-naïve either via clinical history (CoronaVac vaccinees) or nucleocapsid antibody testing (BNT162b2 vaccinees).

RESULTS

All antibodies peaked 20-30 days post-inoculation. In BNT162b2 vaccinees, all post-booster antibodies were significantly higher than second-dose peaks. In CoronaVac vaccinees, IgG showed no significant differences between peak third-/second-dose titers (difference of 56.0 BAU/mL, 95% CI of -17.1 to 129, p = 0.0894). The post-vaccination titers of all antibodies in BNT162b2 vaccinees were significantly higher than those in CoronaVac vaccinees at all time points. Post-booster, all antibodies declined in 90 days; the final total/IgG/N-Ab titers were 7536 BAU/mL, 1276 BAU/mL and 12.5 μg/mL in BNT162b2 vaccinees and 646 BAU/mL, 62.4 BAU/mL and 0.44 μg/mL in CoronaVac vaccinees.

CONCLUSION

The mRNA vaccine generated more robust total S-Ab, IgG and N-Ab responses after the second and third vaccinations.

Effectiveness of an inactivated Covid-19 vaccine with homologous and heterologous boosters against Omicron in Brazil

The effectiveness of inactivated vaccines (VE) against symptomatic and severe COVID-19 caused by omicron is unknown. We conducted a nationwide, test-negative, case-control study to estimate VE for homologous and heterologous (BNT162b2) booster doses in adults who received two doses of CoronaVac in Brazil in the Omicron context. Analyzing 1,386,544 matched-pairs, VE against symptomatic disease was 8.6% (95% CI, 5.6-11.5) and 56.8% (95% CI, 56.3-57.3) in the period 8-59 days after receiving a homologous and heterologous booster, respectively. During the same interval, VE against severe Covid-19 was 73.6% (95% CI, 63.9-80.7) and 86.0% (95% CI, 84.5-87.4) after receiving a homologous and heterologous booster, respectively. Waning against severe Covid-19 after 120 days was only observed after a homologous booster. Heterologous booster might be preferable to individuals with completed primary series inactivated vaccine.