COVID-19 Death and BCG Vaccination Programs Worldwide

Non-specific protection against severe COVID-19 associated to typhoid fever and DTP vaccination

Trained immunity (TRAIM) or the enhanced non-specific immune response after primary stimulation by infection or vaccination is a recent but well-recognized concept. To verify its predictions, our objective was to determine the effects of two bacterial vaccines, typhoid fever (TFV) and diphtheria-tetanus-pertussis (DTP) on the infection, hospitalization and death frequencies associated to COVID-19 in a retrospective study on subjects vaccinated or not with TFV and DTP in the 4 years prior to the start of COVID-19 pandemia in the Basque Country (Spain). The studied outcome records were split into two periods according to COVID-19 vaccination, the pre-vaccination (ACV) from March to December 2020 and the post-vaccination (PCV) from September 2021 to June 2022). In total, 13,673 subjects were vaccinated against TFV and 42,997 against DTP. A total of 2,005,084 individual records were studied in the ACV period and 1,436,693 in the PCV period. The proportion of infection, hospitalization and death associated to COVID-19 among controls in ACV was 4.97 %, 7.14 % and 3.54 %, respectively vs. 7.20 %, 2.24 % and 0.10 % among TFV subjects. Regarding DTP, the proportions were 4.97 %, 7.12 % and 3.58 % for controls and 5.79 %, 5.79 % and 0.80 % for vaccinees. In the PCV period, the proportion of infection, hospitalization and death among controls was 21.89 %, 2.62 % and 0.92 %, respectively vs. 31.19 %, 0.76 %, 0.00 % among TFV. For DTP, infection, hospitalization and death proportions were 21.89 %, 2.62 % and 0.92 %, respectively, among controls vs. 32.03 %, 1.85 % and 0.24 % among vaccinated subjects. The corresponding combined ACV and PCV odds ratios (OR) for SARS-CoV2 infection were 1.505 (95%CI 1.455-1.558; p < 0.0001; reduction -41.85 %) and 1.633 (95%CI 1.603-1.662; p < 0.0001; reduction -51.74 %), for TFV and DTP, respectively. Regarding COVID-19 associated hospitalization, the OR were 0.295 (95%CI 0.220-0.396; p = 0.0001; reduction 69.74 %) and 0.667 (95%CI 0.601-0.741; p = 0.0001; reduction 32.44 %), for TFV and DTP, respectively). COVID-19 associated death OR were 0.016 (95%CI 0.002-0.113, p < 0.0001; reduction 98.38 %) and 0.212 (95%CI 0.161-0.280; p = 0.0001; reduction 78.52 %), for TFV and DTP, respectively. We conclude that TRAIM effects by TFV and DTP vaccination in the four years prior to the pandemic SARS-CoV2 were supported by slightly increased infection rates, but strongly reduced COVID-19 associated hospitalization and death rates.

Tuberculosis Coinfection among COVID-19 Patients: Clinical Presentation and Mortality in a Tertiary Lung Hospital in Indonesia

BACKGROUND

Tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are the top two killers of infectious disease. We aimed to determine the association of TB coinfection with the inhospital mortality of COVID-19 patients in Indonesia as a TB-endemic country.

METHODS

We conducted a retrospective cohort study in a tertiary lung hospital in Indonesia. All TB-coinfected COVID-19 patients who were hospitalized between January 2020 and December 2021 were included in the study. COVID-19 patients without TB were randomly selected for the control group. Clinical characteristics and laboratory results were assessed. Survival analysis was performed to determine the estimated death rate and median survival time (MST). Multivariate Cox regression analysis was conducted to define the association of TB coinfection with the in-hospital mortality of COVID-19.

RESULTS

We included 86 (8.3%) TB coinfections among 1034 confirmed COVID-19 patients. TB coinfection patients had younger age, malnutrition, and different symptoms compared to the COVID-19 group. TB-coinfected patients had a lower estimated death rate than the COVID-19 group (6.5 vs. 18.8 per 1000 population). MST in the COVID-19 group was 38 (interquartile range 16-47) days, whereas the same observation time failed to determine the MST in the TB coinfection group. TB coinfection had a crude hazard ratio of mortality 0.37 (95% confidence interval [CI] 0.15-0.94, P = 0. 004). The final model analysis including age, sex, and lymphocyte as confounding factors resulted in an adjusted HR of mortality 0.31 (95% CI 0.1-0.9).

CONCLUSION

This study showed TB coinfection was negatively associated with the in-hospital mortality of COVID-19.

Strategies and Trends in COVID-19 Vaccination Delivery: What We Learn and What We May Use for the Future

Vaccination has been the most effective way to control the outbreak of the COVID-19 pandemic. The numbers and types of vaccines have reached considerable proportions, even if the question of vaccine procedures and frequency still needs to be resolved. We have come to learn the necessity of defining vaccination distribution strategies with regard to COVID-19 that could be used for any future pandemics of similar gravity. In fact, vaccine monitoring implies the existence of a strategy that should be measurable in terms of input and output, based on a mathematical model, including death rates, the spread of infections, symptoms, hospitalization, and so on. This paper addresses the issue of vaccine diffusion and strategies for monitoring the pandemic. It provides a description of the importance and take up of vaccines and the links between procedures and the containment of COVID-19 variants, as well as the long-term effects. Finally, the paper focuses on the global scenario in a world undergoing profound social and political change, with particular attention on current and future health provision. This contribution would represent an example of vaccination experiences, which can be useful in other pandemic or epidemiological contexts.

Protection against tuberculosis achieved by dissolving microneedle patches loaded with live Mycobacterium paragordonae in a BCG prime-boost strategy

Introduction

Skin vaccination using dissolving microneedle patch (MNP) technology for transdermal delivery is a promising vaccine delivery strategy to overcome the limitations of the existing vaccine administration strategies using syringes. To improve the traditional microneedle mold fabrication technique, we introduced droplet extension (DEN) to reduce drug loss. Tuberculosis remains a major public health problem worldwide, and BCG revaccination had failed to increase the protective efficacy against tuberculosis. We developed an MNP with live Mycobacterium paragordonae (Mpg) (Mpg-MNP) as a candidate of tuberculosis booster vaccine in a heterologous prime-boost strategy to increase the BCG vaccine efficacy.

Materials and methods

The MNPs were fabricated by the DEN method on a polyvinyl alcohol mask film and hydrocolloid-adhesive sheet with microneedles composed of a mixture of mycobacteria and hyaluronic acid. We assessed the transdermal delivery efficiency by comparing the activation of the dermal immune system with that of subcutaneous injection. A BCG prime Mpg-MNP boost regimen was administered to a mouse model to evaluate the protective efficacy against M. tuberculosis.

Results

We demonstrated the successful transdermal delivery achieved by Mpg-MNP compared with that observed with BCG-MNP or subcutaneous vaccination via an increased abundance of MHCII-expressing Langerin+ cells within the dermis that could migrate into draining lymph nodes to induce T-cell activation. In a BCG prime-boost regimen, Mpg-MNP was more protective than BCG-only immunization or BCG-MNP boost, resulting in a lower bacterial burden in the lungs of mice infected with virulent M. tuberculosis. Mpg-MNP-boosted mice showed higher serum levels of IgG than BCG-MNP-boosted mice. Furthermore, Ag85B-specific T-cells were activated after BCG priming and Mpg-MNP boost, indicating increased production of Th1-related cytokines in response to M. tuberculosis challenge, which is correlated with enhanced protective efficacy.

Discussion

The MNP fabricated by the DEN method maintained the viability of Mpg and achieved effective release in the dermis. Our data demonstrate a potential application of Mpg-MNP as a booster vaccine to enhance the efficacy of BCG vaccination against M. tuberculosis. This study produced the first MNP loaded with nontuberculous mycobacteria (NTM) to be used as a heterologous booster vaccine with verified protective efficacy against M. tuberculosis.

An analysis of suicide rates in Kerman province, the largest province in Iran, before and after COVID-19: (2017-2020)

This study aimed to investigate the suicide incidence rate in Kerman before and after the pandemic and the characteristics of suicides. During four years, 642 suicide occurred in Kerman province. The suicide rate of suicide has increased in 2020 compared to previous years. Suicide among females, singles, people with bachelor's degrees, students, governmental, non-governmental occupations, and people without a history of mental illness, and suicide history increased in 2020. Identifying individuals at risk is crucial in order to get exceptional support from the government and society during crises like COVID-19.

Impact of COVID-19 Pandemic on Tuberculosis Preventive Services and Their Post-Pandemic Recovery Strategies: A Rapid Review of Literature

BACKGROUND

Coronavirus disease 2019 (COVID-19) pandemic has disrupted tuberculosis (TB) care and prevention around the world. The aim of this study is to review literature on the impact of COVID-19 on TB preventive services and discuss their policy options during and after the pandemic.

METHODS

We conducted a rapid review of scientific literature on the impact of COVID-19 on TB preventive services and their recovery strategies. After conducting a line-by-line open coding, their codes were applied in the descriptive theme building process, which was guided by the End TB strategy. TB preventive measures were selected and classified into five analytical categories: 1) vaccination against TB, 2) detection and treatment of latent TB infection (LTBI), 3) screening and diagnostics, 4) active case finding and contact tracing, and 5) surveillance.

RESULTS

We identified 93 articles, of which 65 were research articles. During the pandemic, we observed decrease in Bacillus Calmette-Guérin (BCG) coverage, TB diagnostic services, case finding activities, and LTBI management. TB case detection was declined, which was not resumed to the pre-pandemic level after loosening the lock-down. Several recommendations were highlighted: 1) secure BCG stocks and its supply chains, 2) consider catch-up activities of routine immunization and LTBI screening, 3) maintain minimal TB health services, infection prevention and control, and surveillance, 4) leverage laboratory capacity and contact tracing mechanisms, 5) consider simultaneous testing for TB and COVID-19, and 6) Incorporate digital health technologies.

CONCLUSIONS

Our findings and lessons learnt from the pandemic can aid in the development of future national TB control program.

An alternative to airborne droplet transmission route of SARS-CoV-2, the feco-oral route, as a factor shaping COVID-19 pandemic

The Chinese scenario, a rapid increase in the frequency of SARS-CoV-2 infections and sudden decline, is uncommon worldwide. Enormous differences in COVID-19 severity among individual countries are the striking findings of the pandemics. It has been demonstrated that a mild course of COVID-19 is associated with gastrointestinal symptoms, less inflammatory response, and better prognosis. The presence of SARS-CoV-2 was observed longer in the gastrointestinal tract than in respiratory swabs, promoting feco-oral transmissions and mild virus attenuation. The spread of the pandemic and its severity might, consequently, depends on the dominant environmental route of infection and emerging immunity. We hypothesize that the feco-oral SARS-CoV-2 transmission may help to achieve the long-term immunity against COVID-19, since it enables the continuous contact with viral antigens in the gastrointestinal tract, resulting in lower mortality rate. To conclude, countries producing rice through traditional methods developed rapidly emerging long-lasting population immunity, possibly through increased SARS-CoV-2 antigen exposure in the gastrointestinal tract. Our hypothesis brings attention to this potential route of herd immunity against SARS-CoV-2 which warrants further investigation in the future.

Heat inactivated mycobacteria, alpha-gal and zebra fish: insights gained from experiences with two promising trained immunity inductors and a validated animal model

Trained immunity (TRAIM) may be defined as a form of memory where innate immune cells such as monocytes, macrophages, dendritic and natural killer (NK) cells undergo an epigenetic reprogramming that enhances their primary defensive capabilities. Cross-pathogen protective TRAIM can be triggered in different hosts by exposure to live microbes or microbe-derived products such as heat-inactivated Mycobacterium bovis or with the glycan α-Gal to elicit protective responses against several pathogens. We review the TRAIM paradigm using two models representing distinct scales of immune sensitization: the whole bacterial cell and one of its building blocks, the polysaccharides or glycans. Observations point out to macrophage lytic capabilities and cytokine regulation as two key components in nonspecific innate immune responses against infections. The study of the TRAIM response deserves attention to better characterize the evolution of host-pathogen cooperation both for identifying the etiology of some diseases and for finding new therapeutic strategies. In this field, the zebrafish provides a convenient and complete biological system that could help to deepen in the knowledge of TRAIM-mediated mechanisms in pathogen-host interactions. This article is protected by copyright. All rights reserved.

BCG Vaccination: A potential tool against COVID-19 and COVID-19-like Black Swan incidents

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19), and its variants have brought unprecedented impacts to the global public health system, politics, economy, and other fields. Although more than ten COVID-19 specific vaccines have been approved for emergency use, COVID-19 prevention and control still face many challenges. Bacille Calmette–Guérin (BCG) is the only authorized vaccine used to fight against tuberculosis (TB), it has been hypothesized that BCG may prevent and control COVID-19 based on BCG-induced nonspecific immune responses. Herein, we summarized: 1) The nonspecific protection effects of BCG, such as prophylactic protection effects of BCG on nonmycobacterial infections, immunotherapy effects of BCG vaccine, and enhancement effect of BCG vaccine on unrelated vaccines; 2) Recent evidence of BCG's efficacy against SARS-COV-2 infection from ecological studies, analytical analyses, clinical trials, and animal studies; 3) Three possible mechanisms of BCG vaccine and their effects on COVID-19 control including heterologous immunity, trained immunity, and anti-inflammatory effect. We hope that this review will encourage more scientists to investigate further BCG induced non-specific immune responses and explore their mechanisms, which could be a potential tool for addressing the COVID-19 pandemic and COVID-19-like “Black Swan” events to reduce the impacts of infectious disease outbreaks on public health, politics, and economy.

COVID-19 and Beyond: Exploring Public Health Benefits from Non-Specific Effects of BCG Vaccination

Bacille Calmette–Guérin (BCG) vaccination, widely used throughout the world to protect against infant tuberculous meningitis and miliary tuberculosis (TB), can provide broad non-specific protection against infectious respiratory diseases in certain groups. Interest in BCG has seen a resurgence within the scientific community as the mechanisms for non-specific protection have begun to be elucidated. The impact of the COVID-19 pandemic on nearly every aspect of society has profoundly illustrated the pressure that respiratory infections can place on a national healthcare system, further renewing interest in BCG vaccination as a public health policy to reduce the burden of those illnesses. However, the United States does not recommend BCG vaccination due to its variable effectiveness against adult TB, the relatively low risk of Mycobacterium tuberculosis infection in most of the United States, and the vaccine’s interference with tuberculin skin test reactivity that complicates TB screening. In this review, we explore the broad immune training effects of BCG vaccination and literature on the effects of BCG vaccination on COVID-19 spread, disease severity, and mortality. We further discuss barriers to scheduled BCG vaccination in the United States and how those barriers could potentially be overcome.

Repurposing of the childhood vaccines: could we train the immune system against the SARS-CoV-2

INTRODUCTION

The COVID-19 pandemic is a globalized health concern caused by a beta-coronavirus named Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Since December 2019, when this outbreak flared in Wuhan, China, COVID-19 cases have been continuously rising all over the world. Due to the emergence of SARS-CoV-2 mutants, subsequent waves are flowing in a faster manner as compared to the primary wave, which is more contagious and causing higher mortality. Recently, India has emerged as the new epicenter of the second wave by mutants of SARS-CoV-2. After almost eighteen months of this outbreak, some COVID-19 dedicated therapeutics and vaccines are available, and a few are under trial, but the situation is still uncontrolled.

AREA COVERED

This perspective article covers the repurposing of childhood vaccines like Bacille Calmette-Guerin (BCG), Measles, Mumps, Rubella (MMR), and Oral Polio Vaccine (OPV), which are live attenuated vaccines and have been shown the protective effect through 'trained immunity and 'crossreactivity.'

EXPERT OPINION

This perspective article has suggested that combinatorial use of these childhood vaccines might exert a better protective effect along with the available COVID-19 therapeutic and vaccines which could be considered as a preventive option against SARS-CoV-2 infection as well as its subsequent waves.

Citizen science initiative points at childhood BCG vaccination as a risk factor for COVID-19

Current results do not provide conclusive evidence on the effect of BCG vaccination on COVID-19 alone or in combination with other factors. To address this limitation, in this study we used a citizen science initiative on the COVID-19 pandemic to collect data worldwide during 2 October 2020-30 October 2020 (1,233 individuals) in a structured way for analysing factors and characteristics of affected individuals in relation to BCG vaccination. For the first time, the results of our study suggested that vaccination with BCG may increase the risk for COVID-19 at certain age, particularly in individuals vaccinated at childhood. Childhood BCG vaccination increased the likelihood of being diagnosed with COVID-19 fivefold in COVID-19 low-incidence countries and threefold in high-incidence countries. A reasonable explanation for this effect is the activation of certain innate immunity mechanisms associated with inflammatory reactions. These factors should be considered when analysing the risks associated with this global pandemic.

Reliability of Portable Spirometry Performed in the Korea National Health and Nutrition Examination Survey Compared to Conventional Spirometry

Background

The Korea National Health and Nutrition Examination Survey (KNHANES) is a well-designed survey to collect national data, which many researchers have used for their studies. In KNHANES, although portable spirometry was used, its reliability has not been verified.

Methods

We prospectively enrolled 58 participants from four Korean institutions. The participants were classified into normal pattern, obstructive pattern, and restrictive pattern groups according to their previous spirometry results. Lung function was estimated by conventional spirometry and portable spirometry, and the results were compared.

Results

The intraclass correlation coefficients of forced vital capacity (FVC) (coefficient, 9.993; 95% confidence interval [CI], 0.988–0.996), forced expiratory volume in 1 second (FEV₁) (coefficient, 0.997; 95% CI, 0.995–0.998), FEV₁/FVC ratio (coefficient, 0.995; 95% CI, 0.992–0.997), and forced expiratory flow at 25–75% (FEF25–75%; coefficient, 0.991; 95% CI, 0.984–0.994) were excellent (all p<0.001). In the subgroup analysis, the results of the three parameters were similar in all groups. In the overall and subgroup analyses, Pearson’s correlation of all the parameters was also excellent in the total (coefficient, 0.986–0.994; p<0.001) and subgroup analyses (coefficient, 0.915–0.995; p<0.001). In the paired t-test, FVC, FEV₁/FVC, and FEF25–75% estimated by the two instruments were statistically different. However, FEV₁ was not significantly different.

Conclusion

Lung function estimated by portable spirometry was well-correlated with that estimated by conventional spirometry. Although the values had minimal differences between them, we suggest that the spirometry results from the KNHANES are reliable.

Induction of Trained Immunity by Recombinant Vaccines

Vaccines represent an important strategy to protect humans against a wide variety of pathogens and have even led to eradicating some diseases. Although every vaccine is developed to induce specific protection for a particular pathogen, some vaccine formulations can also promote trained immunity, which is a non-specific memory-like feature developed by the innate immune system. It is thought that trained immunity can protect against a wide variety of pathogens other than those contained in the vaccine formulation. The non-specific memory of the trained immunity-based vaccines (TIbV) seems beneficial for the immunized individual, as it may represent a powerful strategy that contributes to the control of pathogen outbreaks, reducing morbidity and mortality. A wide variety of respiratory viruses, including respiratory syncytial virus (hRSV) and metapneumovirus (hMPV), cause serious illness in children under 5 years old and the elderly. To address this public health problem, we have developed recombinant BCG vaccines that have shown to be safe and immunogenic against hRSV or hMPV. Besides the induction of specific adaptive immunity against the viral antigens, these vaccines could generate trained immunity against other respiratory pathogens. Here, we discuss some of the features of trained immunity induced by BCG and put forward the notion that recombinant BCGs expressing hRSV or hMPV antigens have the capacity to simultaneously induce specific adaptive immunity and non-specific trained immunity. These recombinant BCG vaccines could be considered as TIbV capable of inducing simultaneously the development of specific protection against hRSV or hMPV, as well as non-specific trained-immunity-based protection against other pathogenic viruses.

Genetic Variants in Immune Related Genes as Predictors of Responsiveness to BCG Immunotherapy in Metastatic Melanoma Patients

Simple Summary

The study objective was to determine if an SNP (single nucleotide polymorphism)-based immune multi-gene panel has the ability to predict adjuvant BCG (Bacillus Calmette–Guérin) immunotherapy responsiveness post-tumor resection in AJCC (American Joint Committee on Cancer) stages III and IV metastatic melanoma patients. A pilot study followed by further verification and control melanoma patient cohorts involving three phase III multicenter clinical trials was used to verify if an immune gene SNP panel could identify if adjuvant BCG therapy correlates with disease outcomes. We found a specific immune gene SNP panel that could identify which patients would respond to adjuvant BCG immunotherapy, but it was not applicable in the control non-immunotherapy treated patients. These studies provide evidence that SNP immune-gene assessment has utility in predicting melanoma patient’s immunotherapy responses to adjuvant BCG immunotherapy.

Abstract

Adjuvant immunotherapy in melanoma patients improves clinical outcomes. However, success is unpredictable due to inherited heterogeneity of immune responses. Inherent immune genes associated with single nucleotide polymorphisms (SNPs) may influence anti-tumor immune responses. We assessed the predictive ability of 26 immune-gene SNPs genomic panels for a clinical response to adjuvant BCG (Bacillus Calmette-Guérin) immunotherapy, using melanoma patient cohorts derived from three phase III multicenter clinical trials: AJCC (American Joint Committee on Cancer) stage IV patients given adjuvant BCG (pilot cohort; n = 92), AJCC stage III patients given adjuvant BCG (verification cohort; n = 269), and AJCC stage III patients that are sentinel lymph node (SLN) positive receiving no immunotherapy (control cohort; n = 80). The SNP panel analysis demonstrated that the responder patient group had an improved disease-free survival (DFS) (hazard ratio [HR] 1.84, 95% CI 1.09–3.13, p = 0.021) in the pilot cohort. In the verification cohort, an improved overall survival (OS) (HR 1.67, 95% CI 1.07–2.67, p = 0.025) was observed. No significant differences of SNPs were observed in DFS or OS in the control patient cohort. This study demonstrates that SNP immune genes can be utilized as a predictive tool for identifying melanoma patients that are inherently responsive to BCG and potentially other immunotherapies in the future.

SARS-CoV-2: Immune Response Elicited by Infection and Development of Vaccines and Treatments

The World Health Organization (WHO) announced in March a pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This new infectious disease was named Coronavirus Disease 19 (COVID-19), and at October 2020, more than 39,000,000 cases of SARS-CoV-2 have been detected worldwide leading to near 1,100,000 deaths. Clinically, COVID-19 is characterized by clinical manifestations, such as fever, dry cough, headache, and in more severe cases, respiratory distress. Moreover, neurological-, cardiac-, and renal-related symptoms have also been described. Clinical evidence suggests that migration of immune cells to the affected organs can produce an exacerbated release of proinflammatory mediators that contribute to disease and render the immune response as a major player during the development of the COVID-19 disease. Due to the current sanitary situation, the development of vaccines is imperative. Up to the date, 42 prototypes are being tested in humans in different clinical stages, with 10 vaccine candidates undergoing evaluation in phase III clinical trials. In the same way, the search for an effective treatment to approach the most severe cases is also in constant advancement. Several potential therapies have been tested since COVID-19 was described, including antivirals, antiparasitic and immune modulators. Recently, clinical trials with hydroxychloroquine-a promising drug in the beginning-were suspended. In addition, the Food and Drug Administration (FDA) approved convalescent serum administration as a treatment for SARS-CoV-2 patients. Moreover, monoclonal antibody therapy is also under development to neutralize the virus and prevent infection. In this article, we describe the clinical manifestations and the immunological information available about COVID-19 disease. Furthermore, we discuss current therapies under study and the development of vaccines to prevent this disease.