Comparison of control and transmission of COVID-19 across epidemic waves in Hong Kong: an observational study

Vaccination status and disease severity of COVID-19 in different phases of the pandemic

This study aimed to explore the clinical profile and the impact of vaccination status on various health outcomes among COVID-19 patients diagnosed in different phases of the pandemic, during which several variants of concern (VOCs) circulated in South Carolina (SC). The current study included 861,526 adult COVID-19 patients diagnosed between January 2021 and April 2022. We extracted their information about demographic characteristics, vaccination, and clinical outcomes from a statewide electronic health record database. Multiple logistic regression models were used to compare clinical outcomes by vaccination status in different pandemic phases, accounting for key covariates (e.g. historical comorbidities). A reduction in mortality was observed among COVID-19 patients during the whole study period, although there were fluctuations during the Delta and Omicron dominant periods. Compared to non-vaccinated patients, full-vaccinated COVID-19 patients had lower mortality in all dominant variants, including Pre-alpha (adjusted odds ratio [aOR]: 0.33; 95%CI: 0.15-0.72), Alpha (aOR: 0.58; 95%CI: 0.42-0.82), Delta (aOR: 0.28; 95%CI: 0.25-0.31), and Omicron (aOR: 0.29; 95%CI: 0.26-0.33) phases. Regarding hospitalization, full-vaccinated parties showed lower risk of hospitalization than non-vaccinated patients in Delta (aOR: 0.44; 95%CI: 0.41-0.47) and Omicron (aOR: 0.53; 95%CI: 0.50-0.57) dominant periods. The findings demonstrated the protection effect of the COVID-19 vaccines against all VOCs, although some of the full-vaccinated population still have symptoms to varying degrees from COVID-19 disease at different phases of the pandemic.

Pandemic burden in low-income settings and impact of limited and delayed interventions: A granular modelling analysis of COVID-19 in Kabwe, Zambia

OBJECTIVES

Pandemic response in low-income countries (LICs) or settings often suffers from scarce epidemic surveillance and constrained mitigation capacity. The drivers of pandemic burden in such settings, and the impact of limited and delayed interventions remain poorly understood.

METHODS

We analysed COVID-19 seroprevalence and all-cause excess deaths data from the peri-urban district of Kabwe, Zambia between March 2020 and September 2021 with a novel mathematical model. Data encompassed three consecutive waves caused by the wild-type, Beta and Delta variants.

RESULTS

Across all three waves, we estimated a high cumulative attack rate, with 78% (95% credible interval [CrI] 71-85) of the population infected, and a high all-cause excess mortality, at 402 (95% CrI 277-473) deaths per 100,000 people. Ambitiously improving health care to a capacity similar to that in high-income settings could have averted up to 46% (95% CrI 41-53) of accrued excess deaths, if implemented from June 2020 onward. An early and accelerated vaccination rollout could have achieved the highest reductions in deaths. Had vaccination started as in some high-income settings in December 2020 and with the same daily capacity (doses per 100 population), up to 68% (95% CrI 64-71) of accrued excess deaths could have been averted. Slower rollouts would have still averted 62% (95% CrI 58-68), 54% (95% CrI 49-61) or 26% (95% CrI 20-38) of excess deaths if matching the average vaccination capacity of upper-middle-, lower-middle- or LICs, respectively.

CONCLUSIONS

Robust quantitative analyses of pandemic data are of pressing need to inform future global pandemic preparedness commitments.

Acute pancreatitis complicated with diabetic ketoacidosis following COVID-19 mRNA vaccination: a case report

Objective: Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, COVID-19 vaccination has substantially reduced mortality and hospitalization rates worldwide, with rare adverse events reported in clinical settings. Herein, we present a case of acute pancreatitis complicated by diabetic ketoacidosis (DKA) following the third COVID-19 vaccination dose. Patient: A 72-year-old male with a history of diabetes mellitus developed generalized fatigue, mild epigastric pain, nausea, and frequent vomiting after receiving the COVID-19 vaccine. Results: Blood analysis revealed elevated levels of pancreatic enzymes, hyperglycemia, and acidemia. Computed tomography revealed evidence of acute pancreatitis, leading to a diagnosis of both DKA and acute pancreatitis. Treatment with a large volume of saline and intravenous insulin improved both DKA and acute pancreatitis. After a thorough examination, no other factors capable of causing acute pancreatitis were identified. Hence, we concluded that acute pancreatitis was induced by COVID-19 vaccination. Conclusion: Acute pancreatitis is a rare but potentially life-threatening adverse event associated with COVID-19 vaccination. Delaying the treatment or diagnosis of acute pancreatitis can increase mortality risk in patients with both acute pancreatitis and DKA. Hence, it is crucial for healthcare professionals to consider the potential occurrence of acute pancreatitis and DKA following COVID-19 vaccination.

The impact of comorbidity status in COVID-19 vaccines effectiveness before and after SARS-CoV-2 omicron variant in northeastern Mexico: a retrospective multi-hospital study

Introduction

The end of the coronavirus disease 2019 (COVID-19) pandemic has been declared by the World Health Organization on May 5, 2023. Several vaccines were developed, and new data is being published about their effectiveness. However, the clinical trials for the vaccines were performed before the Omicron variant appeared and there are population groups where vaccine effectiveness still needs to be tested. The overarching goal of the present study was to analyze the effects of COVID-19 vaccination before and after the Omicron variant in patients considering comorbidities in a population from Nuevo Leon, Mexico.

Methods

Epidemiological COVID-19 data from the Mexican Social Security Institute were collected from 67 hospitals located in northeastern Mexico, from July 2020 to May 2023, and a total of 669,393 cases were compiled, 255,819 reported a SARS-CoV-2 positive reverse transcription quantitative polymerase chain reaction (RT-qPCR) test or a positive COVID-19 antigen rapid test.

Results

Before Omicron (BO, 2020-2021), after 14 days of two doses of COVID-19 vaccine, BNT162b2 and ChAdOx1 vaccines were effective against infection in non-comorbid and all comorbid subgroups, whereas after Omicron (AO, 2022- 2023) there was no significant effectiveness against infection with none of the vaccines. Regarding hospitalization BO, BNT162b2, ChAdOx1, CoronaVac and mRNA-1273 significantly protected non-comorbid patients whereas BNT162b2, ChAdOx1, and mRNA-1273, protected all comorbid subgroups against hospitalization. AO, BNT162b2, ChAdOx1, CoronaVac and mRNA-1273 were effective against hospitalization in non-comorbid patients whereas for most comorbid subgroups BNT162b2, ChAdOx1 and CoronaVac were effective against hospitalization. Non-comorbid patients were protected against death as an outcome of COVID-19 during the BO period with most vaccines whereas a reduction in effectiveness was observed AO with mRNA-1273 vaccines in patients with hypertension, and diabetes mellitus.

Discussion

BO, COVID-19 vaccines were effective against infection, hospitalization, and death whereas AO, COVID-19 vaccines failed to protect the population from COVID-19 infection. A varying effectiveness against hospitalization and death is observed AO.

Correlates of COVID-19 vaccine uptake among the forcibly displaced: evidence from Libya

BACKGROUND

Vaccine hesitancy and refusal can hinder the control of infectious diseases such as coronavirus disease 2019 (COVID-19). Although forcibly displaced individuals are at high risk of contracting COVID-19, evidence shows that they are less likely to accept the COVID-19 vaccine. Given their predicament, the factors influencing vaccine uptake in the general population might differ vastly from those in displaced populations. Given the limited evidence on vaccine uptake from humanitarian settings, the current study examined the determinants of COVID-19 vaccine uptake among the forcibly displaced in Libya.

METHODS

Data were extracted from the World Bank/United Nations High Commissioner for Refugees (UNHCR) microdata repository. Data were collected between April and July 2021 after the rollout of the first dose of the COVID-19 vaccine in Libya. Percentages, means, and standard deviations were used to quantify the distribution of the sample population. Logistic regression models were employed to identify factors influencing COVID-19 vaccine uptake.

RESULTS

Odds ratios (ORs) with p values are used to present the regression analysis results. The study revealed that people unaffected by COVID-19 were less likely (OR = .71, 95%CI = 0.67-0.89) to accept the vaccine. Similarly, individuals with access to free COVID-19 vaccines were more likely to be vaccinated than those without free vaccines (OR = 38, 95%CI = 0.19-0.28). Finally, the results indicated that individuals were six times more likely to be vaccinated at mass vaccination sites ((OR = 6.31, 95%CI = 5.46- 7.94) and 1.92 times more likely to be vaccinated at local health centers (OR = 1.92, 95%CI = 0.1.72-3.11) than they were at hospitals and distant health facilities.

CONCLUSION

Implementing comprehensive mass vaccination venues, public education initiatives, and awareness campaigns regarding the importance of vaccination can decrease vaccine hesitancy among the forcibly displaced.

Investigation of epidemiological and clinical characteristics of people infected with SARS-CoV-2 during the second pandemic of COVID-19 in Chengdu, China

Objective

This study investigated the epidemiological and clinical characteristics of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infected patients during the second pandemic of COVID-19 (coronavirus disease of 2019) in Chengdu, China. Furthermore, the differences between first infection and re-infection cases were also compared and analyzed to provide evidence for better prevention and control of SARS-CoV-2 re-infection.

Methods

An anonymous questionnaire survey was conducted using an online platform (wjx.cn) between May 20, 2023 to September 12, 2023.

Results

This investigation included 62.94% females and 32.97% of them were 18-30 years old. Furthermore, 7.19-17.18% of the participants either did not receive vaccination at all or only received full vaccination, respectively. Moreover, 577 (57.64%) participants were exposed to cluster infection. The clinical manifestations of these patients were mainly mild to moderate; 78.18% of participants had a fever for 1-3 days, while 37.84% indicated a full course of disease for 4-6 days. In addition, 40.66% of the participants had re-infection and 72.97% indicated their first infection approximately five months before. The clinical symptoms of the first SARS-CoV-2 infection were moderate to severe, while re-infection indicated mild to moderate symptoms (the severity of symptoms other than diarrhea and conjunctival congestion had statistically significant differences) (p < 0.05). Moreover, 70.53 and 59.21% of first and re-infection cases had fever durations of 3-5 and 0-2 days, respectively. Whereas 47.91 and 46.40% of first and re-infection cases had a disease course of 7-9 and 4-6 days.

Conclusion

The SARS-CoV-2 infected individuals in Chengdu, China, during the second pandemic of COVID-19 had mild clinical symptoms and a short course of disease. Furthermore, compared with the first infection, re-infection cases had mild symptoms, low incidences of complications, short fever duration, and course of disease.

Comparative epidemiology of outbreaks caused by SARS-CoV-2 Delta and Omicron variants in China

From 2020 to December 2022, China implemented strict measures to contain the spread of severe acute respiratory syndrome coronavirus 2. However, despite these efforts, sustained outbreaks of the Omicron variants occurred in 2022. We extracted COVID-19 case numbers from May 2021 to October 2022 to identify outbreaks of the Delta and Omicron variants in all provinces of mainland China. We found that omicron outbreaks were more frequent (4.3 vs. 1.6 outbreaks per month) and longer-lasting (mean duration: 13 vs. 4 weeks per outbreak) than Delta outbreaks, resulting in a total of 865,100 cases, of which 85% were asymptomatic. Despite the average Government Response Index being 12% higher (95% confidence interval (CI): 9%, 15%) in Omicron outbreaks, the average daily effective reproduction number (Rt) was 0.45 higher (95% CI: 0.38, 0.52, p < 0.001) than in Delta outbreaks. Omicron outbreaks were suppressed in 32 days on average (95% CI: 26, 39), which was substantially longer than Delta outbreaks (14 days; 95% CI: 11, 19; p = 0.004). We concluded that control measures effective against Delta could not contain Omicron outbreaks in China. This highlights the need for continuous evaluation of new variants' epidemiology to inform COVID-19 response decisions.

Predictive factors of coronavirus disease (COVID-19) vaccination series completion: a one-year longitudinal web-based observational study in Japan

Introduction

Addresing vaccine hesitancy is considered an important goal in management of the COVID-19 pandemic. We sought to understand what factors influenced people, especially those initially hesitant, to receive two or more vaccine doses within a year of the vaccine's release.

Methods

We conducted longitudinal Web-based observational studies of 3,870 individuals. The surveys were conducted at four different time points: January 2021, June 2021, September 2021, and December 2021. In the baseline survey (January 2021), we assessed vaccination intention (i.e., "strongly agree" or "agree" [acceptance], "neutral" [not sure], and "disagree" or "strongly disagree" [hesitance]), and assumptions about coronavirus disease (COVID-19), COVID-19 vaccine, COVID-19-related health preventive behavior, and COVID-19 vaccine reliability. In subsequent surveys (December 2021), we assessed vaccination completion (i.e., ≥2 vaccinations). To investigate the relationship between predictors of COVID-19 vaccination completion, a multivariable logistic regression model was applied. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were calculated while adjusting for gender, age, marital status, presence of children, household income category, and presence of diseases under treatment. In a stratified analysis, predictors were determined based on vaccination intention.

Results

Approximately 96, 87, and 72% of those who demonstrated acceptance, were not sure, or hesitated had been vaccinated after 1 year, respectively. Overall, significant factors associated with COVID-19 vaccine compliance included the influence of others close to the index participant (social norms) (AOR, 1.80; 95% CI, 1.56-2.08; p < 0.001), vaccine confidence (AOR, 1.39; 95% CI, 1.18-1.64; p < 0.001) and structural constraints (no time, inconvenient location of medical institutions, and other related factors) (AOR, 0.80; 95% CI, 0.70-0.91; p = 0.001). In the group of individuals classified as hesitant, significant factors associated with COVID-19 vaccine compliance included social norms (AOR, 2.43; 95% CI, 1.83-3.22; p < 0.001), confidence (AOR, 1.44; 95% CI, 1.10-1.88; p = 0.008), and knowledge (AOR, 0.69; 95% CI, 0.53-0.88; p = 0.003).

Discussion

We found that dissemination of accurate information about vaccines and a reduction in structural barriers to the extent possible enhanced vaccination rates. Once the need for vaccination becomes widespread, it becomes a social norm, and further improvements in these rates can then be anticipated. Our findings may help enhance vaccine uptake in the future.

The moderated-mediation role of risk perception and intolerance of uncertainty in the association between residual symptoms and psychological distress: a cross-sectional study after COVID-19 policy lifted in China

BACKGROUND

A considerable number of individuals infected with COVID-19 experience residual symptoms after the acute phase. However, the correlation between residual symptoms and psychological distress and underlying mechanisms are scarcely studied. We aim to explore the association between residual symptoms of COVID-19 and psychological distress, specifically depression, anxiety, and fear of COVID-19, and examine the role of risk perception and intolerance of uncertainty in the association.

METHODS

A cross-sectional survey was conducted by online questionnaire-based approach in mid-January 2023. Self-reported demographic characteristics, COVID-19-related information, and residual symptoms were collected. Depression, anxiety, fear, risk perception and intolerance of uncertainty were evaluated using the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Fear of COVID-19 Scale (FCV-19S), COVID-19 Risk Perception Scale and Intolerance of Uncertainty Scale-12 (IUS-12), respectively. Linear regression analyses were conducted to explore the associations. A moderated mediation model was then constructed to examine the role of risk perception of COVID-19 and intolerance of uncertainty in the association between residual symptoms and psychological distress.

RESULTS

1735 participants effectively completed the survey. 34.9% of the patients experienced residual symptoms after acute phase of COVID-19. Psychological distress was markedly increased by COVID-19 infection, while residual symptoms had a significant impact on psychological distress (Ps < 0.001), including depression (β = 0.23), anxiety (β = 0.21), and fear of COVID-19 (β = 0.14). Risk perception served as a mediator between residual symptoms and all forms of psychological distress, while intolerance of uncertainty moderated the effect of risk perception on depression and anxiety.

CONCLUSION

A considerable proportion of patients experience residual symptoms after acute phase of COVID-19, which have a significant impact on psychological distress. Risk perception and intolerance of uncertainty play a moderated-mediation role in the association between residual symptoms and depression/anxiety. It highly suggests that effective treatment for residual symptoms, maintaining appropriate risk perception and improving intolerance of uncertainty are critical strategies to alleviate COVID-19 infection-associated psychological distress.