A nicotinic hypothesis for Covid-19 with preventive and therapeutic implications

COVID-19 and Ivermectin: Potential threats associated with human use

Drugs re-purposing due to COVID-19 virus has declared a number of useful candidates for treatment and prevention of the virus. Ivermectin (IVM) has gained much popularity due to a strong background of magical applications against a broad spectrum of pathogens. The in- vitro studies of ivermectin have shown promise, the thorough clinical trials of its efficacy in the treatment and prevention of SARS-CoV-2 are still warranted. Useful strategies for analyzing projected use of IVM in human coronaviruses might be developed. It may be done by concluding ongoing clinical trials and culturing lessons from IVM usage in veterinary practice. The potential toxicity and careful dosage analyses are urgently required before declaring it as an anti-SARS-CoV-2 drug candidate. This manuscript overviews the background and potential threats associated with the off-label use of IVM as prophylactic drug or treatment option against COVID-19 virus.

Exposure to health misinformation about COVID-19 and increased tobacco and alcohol use: a population-based survey in Hong Kong

INTRODUCTION

Health information about COVID-19 has been circulating in social networking sites, including unproven claims that smoking and alcohol drinking could protect against COVID-19. We examined if exposure to such claims was associated with changes in tobacco and alcohol consumption.

METHODS

We conducted a population-based, landline and mobile phone survey of 1501 randomly sampled adults aged 18 years or older (47.5% male) in Hong Kong in April 2020. Respondents reported if they had ever seen claims that 'smoking/alcohol drinking can protect against COVID-19' from popular social networking platforms. Current tobacco and alcohol users reported if they had increased or reduced their consumption since the outbreak. Prevalence data were weighted by sex, age and education of the general adult population.

RESULTS

19.0% (95% CI 16.8% to 21.4%) of all respondents reported having seen claims that 'smoking/alcohol drinking can protect against COVID-19' from social networking sites. Multinomial logistic regression showed that exposure to the claims was significantly associated with increased tobacco use (OR 2.37, 95% CI 1.08 to 5.20) in current tobacco users (N=280) and increased alcohol use (OR 4.16, 95% CI 2.00 to 8.67) in current drinkers (N=722), adjusting for sex, age, education level, alcohol/tobacco use status, home isolation, anxiety and depressive symptoms, and survey method.

CONCLUSION

Our results first showed that exposure to health misinformation that smoking/alcohol drinking can protect against COVID-19 was associated with self-reported increases in tobacco and alcohol consumption in Chinese during the pandemic.

High SARS-CoV-2 seroprevalence in persons experiencing homelessness and shelter workers from a day-shelter in São Paulo, Brazil

Brazil presents one of the highest COVID-19 death tolls in the world. The initial SARS-CoV-2 epicenter was São Paulo city. As of 2019, the homeless population of São Paulo city was estimated at 24,344 individuals, the largest national homeless population. The present study aimed to concomitantly assess the molecular and serological prevalence and associated risk factors of SARS-CoV-2 infection in a homeless population and related shelter workers from a day-shelter. Serum samples, nasopharyngeal and oropharyngeal swabs of persons who are homeless and shelter workers collected from August 25^th to 27^th, 2020 were tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies by ELISA and SARS-CoV-2 RNA by RT-qPCR, respectively. All swab samples tested negative by RT-qPCR. Seropositivity of IgM and IgG was 5/203 (2.5%) and 111/203 (54.7%) in persons who are homeless, and 5/87 (5.7%) and 41/87 (47.1%) in shelter workers, respectively, with no statistical differences between groups. The high seroprevalence found herein indicates early environmental and urban spreading of SARS-CoV-2, associated with sociodemographic and economic vulnerability.

Brazil is one of the world’s most social-economically unequal countries, with a rising homeless population potentialized by the SARS-CoV-2 pandemic, particularly in its largest city, São Paulo. While few studies, mostly in high-income countries, have addressed the impact of the coronavirus pandemic on homeless populations, none has been carried out in Brazil. Herein, we report a high SARS-CoV-2 IgG seroprevalence in a homeless population, with 111/203 (54.7%) seropositive individuals. At the time of the study (August 25^th- 27^th 2020), both homeless and social worker populations showed no active SARS-CoV-2 infection, indicating that they were likely exposed sometime within the pandemic’s first peak in the city. Our study has also shown significant risk and protective factors for SARS-CoV-2 infection, including that Black shelter workers were at higher risk of SARS-CoV-2 infection when compared with the white shelter workers.

High Perceived Susceptibility to and Severity of COVID-19 in Smokers Are Associated with Quitting-Related Behaviors

A growing body of evidence shows smoking is a risk factor for coronavirus disease (COVID-19). We examined the associations of quitting-related behaviors with perceived susceptibility to and severity of COVID-19 in smokers. We conducted a telephone survey of 659 community-based adult smokers (81.7% male) in Hong Kong, where there was no lockdown. Exposure variables were perceptions that smoking can increase the risk of contracting COVID-19 (perceived susceptibility) and its severity if infected (perceived severity). Outcome variables were quit attempts, smoking reduction since the outbreak of the pandemic, and intention to quit within 30 days. Covariates included sex, age, education, heaviness of smoking, psychological distress, and perceived danger of COVID-19. High perceived susceptibility and severity were reported by 23.9% and 41.7% of participants, respectively. High perceived susceptibility was associated with quit attempts (prevalence ratio (PR) 2.22, 95% CI 1.41–3.49), smoking reduction (PR 1.75, 95% CI 1.21–2.51), and intention to quit (PR 2.31, 95% CI 1.40–3.84). Perceived severity of COVID-19 was associated with quit attempts (PR 1.64, 95% CI 1.01–2.67) but not with smoking reduction or intention to quit. To conclude, the perceived susceptibility to and severity of COVID-19 in smokers were associated with quitting-related behaviors in current smokers, which may have important implications for smoking cessation amid the pandemic.

Impact of air pollution and smoking on COVID-19: a review

Background

The 21st century already witnessed many deadly epidemics and pandemics. The major ones were respiratory tract infections like SARS (2003), H1N1 (2009), MERS (2012) and the most recent pandemic COVID-19 (2019). The COVID-19 story begins when pneumonia of unknown cause was reported in the WHO country office of China at the end of 2019. SARS-CoV-2 is the causative agent that enters the host through the receptor ACE2, a component of the renin–angiotensin system.

Main body of the abstract

Symptoms of COVID-19 varies from patient to patient. It is all about the immunity and health status of the individual that decides the severity of the disease. The review focuses on the significant and often prevailing factors, those that influence the lung function. The factors that compromise the lung functions which may prepare the ground for severe COVID-19 infection are interestingly looked into. Focus was more on air pollution and cigarette smoke.

Short conclusion

The fact that the forested areas across the world show very low COVID-19 infection rate suggests that we are in need of the “Clean Air” on the fiftieth anniversary of World Earth Day. As many policies are implemented worldwide to protect from SARS-CoV-2, one simple remedy that we forgot was clean air can save lives. SARS-CoV-2 infects our lungs, and air pollution makes us more susceptible. In this crucial situation, the focus is only on the main threat; all other conditions are only in words to console the situation.

Twitter discourse on nicotine as potential prophylactic or therapeutic for COVID-19

Background

An unproven “nicotine hypothesis” that indicates nicotine's therapeutic potential for COVID-19 has been proposed in recent literature. This study is about Twitter posts that misinterpret this hypothesis to make baseless claims about benefits of smoking and vaping in the context of COVID-19. We quantify the presence of such misinformation and characterize the tweeters who post such messages.

Methods

Twitter premium API was used to download tweets (n = 17,533) that match terms indicating (a) nicotine or vaping themes, (b) a prophylactic or therapeutic effect, and (c) COVID-19 (January-July 2020) as a conjunctive query. A constraint on the length of the span of text containing the terms in the tweets allowed us to focus on those that convey the therapeutic intent. We hand-annotated these filtered tweets and built a classifier that identifies tweets that extrapolate the nicotine hypothesis to smoking/vaping with a positive predictive value of 85%. We analyzed the frequently used terms in author bios, top Web links, and hashtags of such tweets.

Results

21% of our filtered COVID-19 tweets indicate a vaping or smoking-based prevention/treatment narrative. Qualitative analyses show a variety of ways therapeutic claims are being made and tweeter bios reveal pre-existing notions of positive stances toward vaping.

Conclusion

The social media landscape is a double-edged sword in tobacco communication. Although it increases information reach, consumers can also be subject to confirmation bias when exposed to inadvertent or deliberate framing of scientific discourse that may border on misinformation. This calls for circumspection and additional planning in countering such narratives as the COVID-19 pandemic continues to ravage our world. Our results also serve as a cautionary tale in how social media can be leveraged to spread misleading information about tobacco products in the wake of pandemics.

Twitter Discourse on Nicotine as Potential Prophylactic or Therapeutic for COVID-19

Background:

An unproven “nicotine hypothesis” that indicates nicotine’s therapeutic potential for COVID-19 has been proposed in recent literature. This study is about Twitter posts that misinterpret this hypothesis to make baseless claims about benefits of smoking and vaping in the context of COVID-19. We quantify the presence of such misinformation and characterize the tweeters who post such messages.

Methods:

Twitter premium API was used to download tweets (n = 17,533) that match terms indicating (a) nicotine or vaping themes, (b) a prophylactic or therapeutic effect, and (c) COVID-19 (January-July 2020) as a conjunctive query. A constraint on the length of the span of text containing the terms in the tweets allowed us to focus on those that convey the therapeutic intent. We hand-annotated these filtered tweets and built a classifier that identifies tweets that extrapolate the nicotine hypothesis to smoking/vaping with a positive predictive value of 85%. We analyzed the frequently used terms in author bios, top Web links, and hashtags of such tweets.

Results:

21% of our filtered COVID-19 tweets indicate a vaping or smoking-based prevention/treatment narrative. Qualitative analyses show a variety of ways therapeutic claims are being made and tweeter bios reveal pre-existing notions of positive stances toward vaping.

Conclusion:

The social media landscape is a double-edged sword in tobacco communication. Although it increases information reach, consumers can also be subject to confirmation bias when exposed to inadvertent or deliberate framing of scientific discourse that may border on misinformation. This calls for circumspection and additional planning in countering such narratives as the COVID-19 pandemic continues to ravage our world. Our results also serve as a cautionary tale in how social media can be leveraged to spread misleading information about tobacco products in the wake of pandemics.

Antecedents and Consequences of Smoking Cessation Intention in the Context of the Global COVID-19 Infodemic

A growing body of scientific studies has been published to inform responses to the ongoing coronavirus pandemic, and some have claimed that cigarette smoking has a beneficial or mixed effect on the prevention and treatment of COVID-19. The presentation of such findings, unfortunately, has created an infodemic. This study integrated the theory of planned behavior and the health belief model and incorporated findings on addiction from the medical literature to predict cessation intention and support for tobacco control measures in the context of the COVID-19 infodemic. The study found that cessation intention partially mediated the effect of perceived severity and fully mediated the effects of perceived benefits, self-efficacy, and addiction on support for control measures. In addition, a positively-valenced message of the effect of smoking on the prevention and treatment of COVID-19 vs. a mixedly-valenced message was significant in predicting cessation intention, and the positively-valenced message of smoking indirectly predicted support for tobacco control measures. Perceived susceptibility, barriers, and subjective norms, however, exerted neither direct nor indirect effects on the two outcome variables.

COVID-19: a pandemic converged with global tobacco epidemic and widespread vaping-state of the evidence

This review highlights the convergence of three global health challenges at a crossroad where the pandemic of coronavirus disease 2019 (COVID-19) meets the tobacco epidemic and vaping. It begins with an overview of the current knowledge on the biology, pathophysiology and epidemiology of COVID-19. It then presents the state of smoking and vaping during the pandemic by summarizing the published data on prevalence, use patterns, product availability/accessibility, sales records and motivation to quit before and after the start of the pandemic. It highlights the state of evidence on the association of tobacco product use with COVID-19 infection and transmission rates, symptom severity and clinical outcomes. Also discussed are proposed biological mechanisms and behavioral factors that may modulate COVID-19 risk in tobacco product users. Furthermore, competing hypotheses on the protective effect of nicotine against COVID-19 as well as the claimed ‘smokers’ paradox’ are discussed. Considerations and challenges of COVID-19 vaccination in tobacco product users are underscored. Collectively, the present data show an ‘incomplete’ but rapidly shaping picture on the association of tobacco product use and COVID-19 infection, disease course and clinical outcomes. Evidence is also growing on the mechanisms by which tobacco product use may contribute to COVID-19 pathophysiology. Although we await definitive conclusions on the relative risk of COVID-19 infection in tobacco product users, compelling data confirm that many comorbidities associated with/caused by smoking predispose to COVID-19 infection, severe disease and poor prognosis. Additionally, it is becoming increasing clear that should smokers get the disease, they are more likely to have serious health consequences.

Attenuation of clinical and immunological outcomes during SARS-CoV-2 infection by ivermectin

The devastating pandemic due to SARS-CoV-2 and the emergence of antigenic variants that jeopardize the efficacy of current vaccines create an urgent need for a comprehensive understanding of the pathophysiology of COVID-19, including the contribution of inflammation to disease. It also warrants for the search of immunomodulatory drugs that could improve disease outcome. Here, we show that standard doses of ivermectin (IVM), an anti-parasitic drug with potential immunomodulatory activities through the cholinergic anti-inflammatory pathway, prevent clinical deterioration, reduce olfactory deficit, and limit the inflammation of the upper and lower respiratory tracts in SARS-CoV-2-infected hamsters. Whereas it has no effect on viral load in the airways of infected animals, transcriptomic analyses of infected lungs reveal that IVM dampens type I interferon responses and modulates several other inflammatory pathways. In particular, IVM dramatically reduces the Il-6/Il-10 ratio in lung tissue and promotes macrophage M2 polarization, which might account for the more favorable clinical presentation of IVM-treated animals. Altogether, this study supports the use of immunomodulatory drugs such as IVM, to improve the clinical condition of SARS-CoV-2-infected patients.

Predicted structural mimicry of spike receptor-binding motifs from highly pathogenic human coronaviruses

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Potential coronavirus spike protein mimicry revealed by structural comparison.

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Human and non-human protein potential interactions with virus identified.

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Predicted structural mimicry corroborated by protein–protein docking.

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Epitope-based alignments may help guide vaccine efforts.

Viruses often encode proteins that mimic host proteins in order to facilitate infection. Little work has been done to understand the potential mimicry of the SARS-CoV-2, SARS-CoV, and MERS-CoV spike proteins, particularly the receptor-binding motifs, which could be important in determining tropism and druggability of the virus. Peptide and epitope motifs have been detected on coronavirus spike proteins using sequence homology approaches; however, comparing the three-dimensional shape of the protein has been shown as more informative in predicting mimicry than sequence-based comparisons. Here, we use structural bioinformatics software to characterize potential mimicry of the three coronavirus spike protein receptor-binding motifs. We utilize sequence-independent alignment tools to compare structurally known protein models with the receptor-binding motifs and verify potential mimicked interactions with protein docking simulations. Both human and non-human proteins were returned for all three receptor-binding motifs. For example, all three were similar to several proteins containing EGF-like domains: some of which are endogenous to humans, such as thrombomodulin, and others exogenous, such as Plasmodium falciparum MSP-1. Similarity to human proteins may reveal which pathways the spike protein is co-opting, while analogous non-human proteins may indicate shared host interaction partners and overlapping antibody cross-reactivity. These findings can help guide experimental efforts to further understand potential interactions between human and coronavirus proteins.

Current Use of Ivermectin in Dermatology, Tropical Medicine, and COVID-19: An Update on Pharmacology, Uses, Proven and Varied Proposed Mechanistic Action

Ivermectin is a broad-spectrum antiparasitic drug with anti-inflammatory, anti-viral, anti-bacterial, and anti-tumor effects. In this review, we discuss the history, pharmacology, multimodal actions, indications in dermatology and tropical medicine, therapeutic and prophylactic use of ivermectin in COVID-19, safety, adverse effects, special considerations, and drug interactions of ivermectin.

Structure-function relations of the SARS-CoV-2 spike protein and impact of mutations in the variants of concern

This review covers the main features of the severe acquired respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, its interaction with the main entry receptor, the human angiotensin converting enzyme 2 (ACE2), and the subsequent membrane fusion step. The focus is on the structural organization of these proteins and mechanistic aspects of their interactions that lead to cytoplasmic release of the viral genome. The most potently neutralizing antibodies against SARS-CoV-2 were shown to interfere with the spike/ACE2 interaction. I thus also review the location and the potential impact of mutations in the spike protein observed in the variants of concern that emerged concomitantly with acquired immunity in the population after one year of virus circulation. Understanding how these interactions affect the spike/ACE2 interactions and the subsequent spike-protein-induced membrane fusion reaction is important to stay one step ahead of the virus evolution and develop efficient countermeasures.

Potential Impact of a Paper About COVID-19 and Smoking on Twitter Users' Attitudes Toward Smoking: Observational Study

Background

A cross-sectional study (Miyara et al, 2020) conducted by French researchers showed that the rate of current daily smoking was significantly lower in patients with COVID-19 than in the French general population, implying a potentially protective effect of smoking.

Objective

We aimed to examine the dissemination of the Miyara et al study among Twitter users and whether a shift in their attitudes toward smoking occurred after its publication as preprint on April 21, 2020.

Methods

Twitter posts were crawled between April 14 and May 4, 2020, by the Tweepy stream application programming interface, using a COVID-19–related keyword query. After filtering, the final 1929 tweets were classified into three groups: (1) tweets that were not related to the Miyara et al study before it was published, (2) tweets that were not related to Miyara et al study after it was published, and (3) tweets that were related to Miyara et al study after it was published. The attitudes toward smoking, as expressed in the tweets, were compared among the above three groups using multinomial logistic regression models in the statistical analysis software R (The R Foundation).

Results

Temporal analysis showed a peak in the number of tweets discussing the results from the Miyara et al study right after its publication. Multinomial logistic regression models on sentiment scores showed that the proportion of negative attitudes toward smoking in tweets related to the Miyara et al study after it was published (17.07%) was significantly lower than the proportion in tweets that were not related to the Miyara et al study, either before (44/126, 34.9%; P<.001) or after the Miyara et al study was published (68/198, 34.3%; P<.001).

Conclusions

The public’s attitude toward smoking shifted in a positive direction after the Miyara et al study found a lower incidence of COVID-19 cases among daily smokers.

Microglial Implications in SARS-CoV-2 Infection and COVID-19: Lessons From Viral RNA Neurotropism and Possible Relevance to Parkinson's Disease

Since December 2019, humankind has been experiencing a ravaging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak, the second coronavirus pandemic in a decade after the Middle East respiratory syndrome coronavirus (MERS-CoV) disease in 2012. Infection with SARS-CoV-2 results in Coronavirus disease 2019 (COVID-19), which is responsible for over 3.1 million deaths worldwide. With the emergence of a second and a third wave of infection across the globe, and the rising record of multiple reinfections and relapses, SARS-CoV-2 infection shows no sign of abating. In addition, it is now evident that SARS-CoV-2 infection presents with neurological symptoms that include early hyposmia, ischemic stroke, meningitis, delirium and falls, even after viral clearance. This may suggest chronic or permanent changes to the neurons, glial cells, and/or brain vasculature in response to SARS-CoV-2 infection or COVID-19. Within the central nervous system (CNS), microglia act as the central housekeepers against altered homeostatic states, including during viral neurotropic infections. In this review, we highlight microglial responses to viral neuroinfections, especially those with a similar genetic composition and route of entry as SARS-CoV-2. As the primary sensor of viral infection in the CNS, we describe the pathogenic and neuroinvasive mechanisms of RNA viruses and SARS-CoV-2 vis-à-vis the microglial means of viral recognition. Responses of microglia which may culminate in viral clearance or immunopathology are also covered. Lastly, we further discuss the implication of SARS-CoV-2 CNS invasion on microglial plasticity and associated long-term neurodegeneration. As such, this review provides insight into some of the mechanisms by which microglia could contribute to the pathophysiology of post-COVID-19 neurological sequelae and disorders, including Parkinson's disease, which could be pervasive in the coming years given the growing numbers of infected and re-infected individuals globally.

Transdermal nicotine in non-smokers: A systematic review to design COVID-19 clinical trials

Recent data show an interaction between COVID-19 and nicotine and indicate the need for an assessment of transdermal nicotine use in non-smokers. Assessments have been conducted into the short-term cognitive effects of nicotine and into diseases such as Parkinson's, Tourette syndrome, ADHD or ulcerative colitis.

METHODS

Analyses of nicotine administration protocols and safety were conducted after reviewing Medline and Science Direct databases performing a search using the words [transdermal nicotine] AND [non-smoker] AND selected diseases.

RESULTS

Among 298 articles identified, there were 35 reviewed publications reporting on 33 studies of non-smokers receiving transdermal nicotine for >48hours. In the 16 randomized trials, 7 crossover, 1 case/control and 9 open studies patients received an initial nicotine dose of between 2.5mg and 15mg/day. In 22 studies, daily doses increased by 2 to 7 steps in 3 to 96 days until the dose was between 5mg and 105mg/day. The target nicotine dose was 19.06±20.89mg/day. The 987 non-smokers (534 never-smokers, 326 ex-smokers and 127 classified as "non-smokers") received or did not receive nicotine. The most common side-effects were nausea and skin itching. Forty-three (7.1%) non-smokers stopped treatment because of an adverse event of nicotine. No hospitalization related to nicotine side-effects were reported.

CONCLUSION

Despite a relatively safe tolerance profile, transdermal nicotine therapy in non-smokers can only be used in clinical trials. There is a lack of formal assessment of the potential risk of developing a tobacco addiction. This review offers baseline data to set a transdermal nicotine protocol for non-smokers with a new purpose.

Regulation of the acetylcholine/α7nAChR anti-inflammatory pathway in COVID-19 patients

The cholinergic system has been proposed as a potential regulator of COVID-19-induced hypercytokinemia. We investigated whole-blood expression of cholinergic system members and correlated it with COVID-19 severity. Patients with confirmed SARS-CoV-2 infection and healthy aged-matched controls were included in this non-interventional study. A whole blood sample was drawn between 9-11 days after symptoms onset, and peripheral leukocyte phenotyping, cytokines measurement, RNA expression and plasma viral load were determined. Additionally, whole-blood expression of native alpha-7 nicotinic subunit and its negative dominant duplicate (CHRFAM7A), choline acetyltransferase and acetylcholine esterase (AchE) were determined. Thirty-seven patients with COVID-19 (10 moderate, 11 severe and 16 with critical disease) and 14 controls were included. Expression of CHRFAM7A was significantly lower in critical COVID-19 patients compared to controls. COVID-19 patients not expressing CHRFAM7A had higher levels of CRP, more extended pulmonary lesions and displayed more pronounced lymphopenia. COVID-19 patients without CHRFAM7A expression also showed increased TNF pathway expression in whole blood. AchE was also expressed in 30 COVID-19 patients and in all controls. COVID-19-induced hypercytokinemia is associated with decreased expression of the pro-inflammatory dominant negative duplicate CHRFAM7A. Expression of this duplicate might be considered before targeting the cholinergic system in COVID-19 with nicotine.

The consequential impact of JUUL on youth vaping and the landscape of tobacco products: The state of play in the COVID-19 era

JUUL is a groundbreaking electronic cigarette (e-cig) and the preeminent vaping product on the market. We present an overview of the rapid and spectacular rise of JUUL and its remarkable fall within the timespan of 2015 - 2020. We highlight JUUL's entering the market in June 2015, becoming the industry leader in mid 2017, and experiencing a litany of setbacks by late 2019 through to early 2020. We address the role played by JUUL in the ongoing epidemic of youth vaping. We also feature competing views on the public health impact of JUUL use (in particular), and e-cig vaping (in general). We further highlight the latest trends in youth vaping and sales records for JUUL and tobacco cigarettes. In view of the ongoing pandemic of COVID-19, we briefly summarize the existing evidence on the relationship between vaping and smoking and the prevalence, disease course, and clinical outcomes of COVID-19.

Demographic and territorial characteristics of COVID-19 cases and excess mortality in the European Union during the first wave

This article explores for a large number of countries in the European Union (plus the United Kingdom) the main demographic differentials in positive tested COVID-19 cases and excess mortality during the first wave in 2020, accounting for differences at territorial level, where population density and size play a main role in the diffusion and effects of the disease in terms of morbidity and mortality. This knowledge complements and refines the epidemiological information about the spread and impact of the virus. For this analysis, we rely on the descriptive exploration of (1) data from The European Surveillance System (TESSy) database developed at the European Centre for Disease Prevention and Control (ECDC) on the number of cases and fatality rates and (2) of weekly mortality data collected by Eurostat. The analysis at territorial level studies the changes in R0-the basic reproduction number-and median excess mortality, across territories with different levels of urbanization. The unique findings of this study encompassing most European Union Member States confirm and define the demographic and territorial differential impacts in terms of infections and fatalities during the first wave of the pandemic in 2020. The information is important for stakeholders at European Union, national and sub-national levels in charge of designing containment measures for COVID-19 and adaptation policies for the future by anticipating the rebound for certain segments of the population with differential medical and economic needs.

[COVID-19 and Smoking - A Position Paper by the DGP Taskforce for Smoking Cessation]

Tobacco smoking is associated with severe health risks. In 2020, the WHO estimated that 8 million people have died due to smoking. Furthermore, smoking tobacco is a well-known risk factor for various infectious pulmonary diseases. The question raised, whether smoking is facilitating SARS-CoV-2-infections and increases adverse outcomes of COVID-19. To answer these questions a narrative review was conducted, finally including 7 systematic reviews with meta-analyses published in January and February 2021. Tobacco smoking was associated with an increased COVID-19 disease severity (odds ratio range of active vs. never smokers 1.55-2.19 and former vs. never smokers 1.20-2.48) and an increased COVID-19 in-hospital mortality (odds ratio range of active vs. never smokers 1.35-1.51 and former vs. never smokers 1.26-2.58). Beside immediate pulmonary toxic effects through active smoking, the cumulative livelong tobacco exposition and subsequent tobacco-associated diseases seem to predominantly predict adverse outcomes in patients with COVID-19. Data regarding an increased risk of infection among smokers is conflicting. However, a large observational study from England with 2.4 million persons reported an association between tobacco smoking and typical symptoms of COVID-19. For e-cigarettes and vaping less data exist, but experimental and first clinical investigations also suggest an increased risk for adverse outcomes for their use and SARS-CoV-2 infections. Especially during the current SARS-CoV-2 pandemic with limited therapeutic options it is particularly important to advise smokers of their increased risks for unfavourable COVID-19 outcomes. Evidence based support for smoking cessation should be offered. In Germany, the existing and well-established methods to support tobacco cessation need to be reimbursed by statutory health insurances.

Sociodemographic determinants and clinical risk factors associated with COVID-19 severity: a cross-sectional analysis of over 200,000 patients in Tehran, Iran

Background

Defining socio-demographic factors, clinical presentations and underlying diseases associated with COVID-19 severity could be helpful in its management. This study aimed to further clarify the determinants and clinical risk factors of the disease severity in patients infected with COVID-19.

Methods

A multi-centre descriptive study on all patients who have been diagnosed with COVID-19 in the province of Tehran from March 2020 up to Dec 2020 was conducted. Data on socio-demographic characteristics, clinical presentations, comorbidities, and the health outcomes of 205,654 patients were examined. Characteristics of the study population were described. To assess the association of study variables with the disease severity, the Chi-Squared test and Multiple Logistic Regression model were applied.

Results

The mean age of the study population was 52.8 years and 93,612 (45.5%) were women. About half of the patients have presented with low levels of blood oxygen saturation. The ICU admission rate was 17.8% and the overall mortality rate was 10.0%. Older age, male sex, comorbidities including hypertension, cancer, chronic respiratory diseases other than asthma, chronic liver diseases, chronic kidney diseases, chronic neurological disorders, and HIV/AIDS infection were risk markers of poor health outcome. Clinical presentations related with worse prognosis included fever, difficulty breathing, impaired consciousness, and cutaneous manifestations.

Conclusion

These results might alert physicians to pay attention to determinants and risk factors associated with poor prognosis in patients with COVID-19. In addition, our findings aid decision makers to emphasise on vulnerable groups in the public health strategies that aim at preventing the spread of the disease and its mortalities.

The Cholinergic and ACE-2-Dependent Anti-Inflammatory Systems in the Lung: New Scenarios Emerging From COVID-19

The renin angiotensin system and the cholinergic anti-inflammatory pathway have been recently shown to modulate lung inflammation in patients with COVID-19. We will show how studies performed on this disease are starting to provide evidence that these two anti-inflammatory systems may functionally interact with each other, a mechanism that could have a more general physiological relevance than only COVID-19 infection.

Association of smoking and cardiovascular disease with disease progression in COVID-19: A systematic review and meta-analysis

The aim of this study was to systematically assess the association between smoking and cardiovascular disease (CVD) and disease progression among novel coronavirus pneumonia (coronavirus disease 2019 (COVID-19)) cases. PubMed database and Cochrane Library database were searched by computer to seek the epidemiological data of COVID-19 cases and literatures regarding CVDs from 1 Jan to 6 October 2020. Two researchers independently conducted literature screening, data collection and the assessment of the risk of bias of the studies included. RevMan 5.2 software was employed for meta-analysis. Funnel plot was adopted to assess the publication bias. On the whole, 21 studies comprising 7041 COVID-19 cases were included. As revealed from the meta-analysis, 14.0% (984/7027) of cases had a history of smoking, and 9.7% (675/6931) were subject to underlying CVDs. Cases with a history of smoking achieved a higher rate of COVID-19 disease progression as opposed to those having not smoked (OR 1.53, 95% CI 1.29–1.81, P < 0.00001), while no significant association could be found between smoking status and COVID-19 disease progression (OR 1.23, 95% CI 0.93–1.63, P = 0.15). Besides, smoking history elevated the mortality rate by 1.91-fold (OR 1.91, 95% CI 1.35–2.69, P = 0.0002). Moreover, underlying CVD elevated the incidence of severe disease by 2.87-fold (OR 2.87, 95% CI 2.29–3.61, P < 0.00001) and mortality by 3.05-fold (OR 3.05, 95% CI 1.82–5.11, P < 0.0001) in COVID-19 cases. As demonstrated from the current evidence, smoking displays a strong association with COVID-19 disease progression and mortality, and intensive tobacco control is imperative. Moreover, cases with CVD show a significantly elevated risk of disease progression and death when subject to COVID-19. However, the association between COVID-19 and CVD, and the potential effect exerted by smoking in the development of the two still require further verifications by larger and higher quality studies.

SARS-Cov-2 spike protein fragment 674-685 protects mitochondria from releasing cytochrome c in response to apoptogenic influence

In spite of numerous studies, many details of SARS-Cov-2 interaction with human cells are still poorly understood. The 674–685 fragment of SARS-Cov-2 spike protein is homologous to the fragment of α-cobratoxin underlying its interaction with α7 nicotinic acetylcholine receptors (nAChRs). The interaction of 674–685 peptide with α7 nAChR has been predicted in silico. In the present paper we confirm this prediction experimentally and investigate the effect of SARS-Cov-2 spike protein peptide on mitochondria, which express α7 nAChRs to regulate apoptosis-related events. We demonstrate that SARS-Cov-2 spike protein peptide 674–685 competes with the antibody against 179–190 fragment of α7 nAChR subunit for the binding to α7-expressing cells and mitochondria and prevents the release of cytochrome c from isolated mitochondria in response to 0.5 mM H₂O₂ but does not protect intact U373 cells against apoptogenic effect of H₂O_2. Our data suggest that the α7 nAChR-binding portion of SARS-Cov-2 spike protein prevents mitochondria-driven apoptosis when the virus is uncoated inside the cell and, therefore, supports the infected cell viability before the virus replication cycle is complete.

Impact of Smoking on Women During the Covid-19 Pandemic

The coronavirus disease 2019 (COVID-19) brought in 2020 an important challenge for health-care systems and authorities. Smoking and its influence on this disease remain, after months of the pandemic, one of the debatable risk factors. From the literature point of view, the focus of most articles is on smoking as a possible general risk factor for all analyzed populations. Women tend to represent a more significant population in exposed occupations. In our mini-review, we try to dig deeper, looking for gender-related health effects of smoking in this pandemic context, its effects on the infection with this novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), on illness severity, and on the rate of hospitalization and mortality. Despite the fact that the male gender is reported in many articles as a predictor of a poor outcome, we suggest that further research is needed to confirm or deny these relationships. Moreover, studies focusing specifically on women in these study populations are required.

Nicotine upregulates ACE2 expression and increases competence for SARS-CoV-2 in human pneumocytes

The coronavirus disease 2019 (COVID-19) pandemic has a variable degree of severity according to underlying comorbidities and life-style. Several research groups have reported an association between cigarette smoking and increased severity of COVID-19. The exact mechanism of action is largely unclear. We exposed low angiotensin-converting enzyme 2 (ACE2)-expressing human pulmonary adenocarcinoma A549 epithelial cells to nicotine and assessed ACE2 expression at different times. We further used the nicotine-exposed cells in a virus neutralisation assay. Nicotine exposure induces rapid and long-lasting increases in gene and protein expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor ACE2, which in turn translates into increased competence for SARS-CoV-2 replication and cytopathic effect. These findings show that nicotine worsens SARS-CoV-2 pulmonary infection and have implications for public health policies.

Role of Cigarette Smoke on Angiotensin-Converting Enzyme-2 Protein Membrane Expression in Bronchial Epithelial Cells Using an Air-Liquid Interface Model

Prevalence studies of current smoking, among hospitalized COVID-19 patients, demonstrated an unexpectedly low prevalence among patients with COVID-19. The aim of the present study was to evaluate the effect of smoke from cigarettes on ACE-2 in bronchial epithelial cells. Normal bronchial epithelial cells (H292) were exposed to smoke by an air-liquid-interface (ALI) system and ACE-2 membrane protein expression was evaluated after 24 h from exposure. Our transcriptomics data analysis showed a significant selective reduction of membrane ACE-2 expression (about 25%) following smoking exposure. Interestingly, we observed a positive direct correlation between ACE-2 reduction and nicotine delivery. Furthermore, by stratifying GSE52237 as a function of ACE-2 gene expression levels, we highlighted 1,012 genes related to ACE-2 in smokers and 855 in non-smokers. Furthermore, we showed that 161 genes involved in the endocytosis process were highlighted using the online pathway tool KEGG. Finally, 11 genes were in common between the ACE-2 pathway in smokers and the genes regulated during endocytosis, while 12 genes with non-smokers. Interestingly, six in non-smokers and four genes in smokers were closely involved during the viral internalization process. Our data may offer a pharmaceutical role of nicotine as potential treatment option in COVID-19.

Spatial and temporal trends in social vulnerability and COVID-19 incidence and death rates in the United States

BACKGROUND

Socially vulnerable communities may be at higher risk for COVID-19 outbreaks in the US. However, no prior studies examined temporal trends and differential effects of social vulnerability on COVID-19 incidence and death rates. Therefore, we examined temporal trends among counties with high and low social vulnerability to quantify disparities in trends over time.

METHODS

We conducted a longitudinal analysis examining COVID-19 incidence and death rates from March 15 to December 31, 2020, for each US county using data from USAFacts. We classified counties using the Social Vulnerability Index (SVI), a percentile-based measure from the Centers for Disease Control and Prevention, with higher values indicating more vulnerability. Using a Bayesian hierarchical negative binomial model, we estimated daily risk ratios (RRs) comparing counties in the first (lower) and fourth (upper) SVI quartiles, adjusting for rurality, percentage in poor or fair health, percentage female, percentage of smokers, county average daily fine particulate matter (PM2.5), percentage of primary care physicians per 100,000 residents, daily temperature and precipitation, and proportion tested for COVID-19.

RESULTS

At the outset of the pandemic, the most vulnerable counties had, on average, fewer cases per 100,000 than least vulnerable SVI quartile. However, on March 28, we observed a crossover effect in which the most vulnerable counties experienced higher COVID-19 incidence rates compared to the least vulnerable counties (RR = 1.05, 95% PI: 0.98, 1.12). Vulnerable counties had higher death rates starting on May 21 (RR = 1.08, 95% PI: 1.00,1.16). However, by October, this trend reversed and the most vulnerable counties had lower death rates compared to least vulnerable counties.

CONCLUSIONS

The impact of COVID-19 is not static but can migrate from less vulnerable counties to more vulnerable counties and back again over time.

A potential interaction between the SARS-CoV-2 spike protein and nicotinic acetylcholine receptors

Changeux et al. (Changeux et al. C. R. Biol. 343:33-39.) recently suggested that the SARS-CoV-2 spike protein may interact with nicotinic acetylcholine receptors (nAChRs) and that such interactions may be involved in pathology and infectivity. This hypothesis is based on the fact that the SARS-CoV-2 spike protein contains a sequence motif similar to known nAChR antagonists. Here, we use molecular simulations of validated atomically detailed structures of nAChRs and of the spike to investigate the possible binding of the Y674-R685 region of the spike to nAChRs. We examine the binding of the Y674-R685 loop to three nAChRs, namely the human α4β2 and α7 subtypes and the muscle-like αβγδ receptor from Tetronarce californica. Our results predict that Y674-R685 has affinity for nAChRs. The region of the spike responsible for binding contains a PRRA motif, a four-residue insertion not found in other SARS-like coronaviruses. The conformational behavior of the bound Y674-R685 is highly dependent on the receptor subtype; it adopts extended conformations in the α4β2 and α7 complexes but is more compact when bound to the muscle-like receptor. In the α4β2 and αβγδ complexes, the interaction of Y674-R685 with the receptors forces the loop C region to adopt an open conformation, similar to other known nAChR antagonists. In contrast, in the α7 complex, Y674-R685 penetrates deeply into the binding pocket in which it forms interactions with the residues lining the aromatic box, namely with TrpB, TyrC1, and TyrC2. Estimates of binding energy suggest that Y674-R685 forms stable complexes with all three nAChR subtypes. Analyses of simulations of the glycosylated spike show that the Y674-R685 region is accessible for binding. We suggest a potential binding orientation of the spike protein with nAChRs, in which they are in a nonparallel arrangement to one another.

COVID-19 and smoking: More severity and death - An experience from Iran

Background

Few studies have shown that smokers are more likely than nonsmokers to contract COVID-19, while others report that smokers are underrepresented among those requiring hospital treatment for this illness. This study was designed and implemented for investigating the severity and outcome of COVID-19 based on underlying smoking status.

Materials and Methods

This was a case-control study that was implemented in Tehran and Ahvaz with all COVID-19 patients from February to July 2020. Patients were divided into two groups of COVID-19 positive (1044 cases) and negative (1231 controls) randomly based on entrance number.

Results

The frequency of smokers in the case group is significantly lower than the control group (15.4% vs. 28%). However, the number of days of hospitalization and the use of more than 3 medications in the group of smokers were significantly higher. A comparison between groups of case and control based on smoking indicates that the death rate was significantly higher in smokers with COVID-19.

Conclusions

The results of this study showed that although the number of smokers in COVID-19 patients is significantly lower, smokers run an aggresive curse and have higher mortality.

The Anti-inflammatory Effect of the Tricyclic Antidepressant Clomipramine and Its High Penetration in the Brain Might Be Useful to Prevent the Psychiatric Consequences of SARS-CoV-2 Infection

At the time of writing (December 2020), coronavirus disease 2019 (COVID-19) has already caused more than one million deaths worldwide, and therefore, it is imperative to find effective treatments. The “cytokine storm” induced by Severe Acute Respiratory Syndrome-Coronavirus type 2 (SARS-CoV-2) is a good target to prevent disease worsening, as indicated by the results obtained with tocilizumab and dexamethasone. SARS-CoV-2 can also invade the brain and cause neuro-inflammation with dramatic neurological manifestations, such as viral encephalitis. This could lead to potentially incapacitating long-term consequences, such as the development of psychiatric disorders, as previously observed with SARS-CoV. Several pathways/mechanisms could explain the link between viral infection and development of psychiatric diseases, especially neuro-inflammation induced by SARS-CoV-2. Therefore, it is important to find molecules with anti-inflammatory properties that penetrate easily into the brain. For instance, some antidepressants have anti-inflammatory action and pass easily through the blood brain barrier. Among them, clomipramine has shown very strong anti-inflammatory properties in vitro, in vivo (animal models) and human studies, especially in the brain. The aim of this review is to discuss the potential application of clomipramine to prevent post-infectious mental complications. Repositioning and testing antidepressants for COVID-19 management could help to reduce peripheral and especially central inflammation and to prevent the acute and particularly the long-term consequences of SARS-CoV-2 infection.

Addictions in the COVID-19 era: Current evidence, future perspectives a comprehensive review

BACKGROUND

In the context of the COVID-19 worldwide pandemic, an up-to-date review of current challenges in addictions is necessary. While large scale disasters may have an impact on substance use and addictions, the use of some substances is also likely to modify the risk of COVID-19 infection or course. Many countries have imposed lockdowns. Whether this quarantine or the end of lockdown measures will have an impact on substance use is discussed. The aim of this review is to gather knowledge for clinicians and to guide public health policies during/after lockdown.

METHODS

PubMed was reviewed in August 6th (2020), to determine the current evidences and observations concerning the addictions and SARS-CoV2. We used all the names of the severe acute respiratory syndrome of coronavirus 2 (SARS-CoV2 previously 2019 nCoV), the name of the coronavirus disease 2019 (COVID-19), and common substances of abuse. For the physiopathological parts, searches were conducted using key words such as "infection" or "pneumonia". For the lockdown effects, key words such as "quarantine", "disaster" or "outbreak" were used.

RESULTS

Overall, pathophysiological data showed an increased risk of infections for individuals with Substance Use Disorders (SUD) and a possible protective role of nicotine. During lockdown, there is a substantial risk of increasing SUDs. Individuals with opioid use disorder are particularly at risk of relapse or of involuntary withdrawal. After lockdown, increase of use may be observed as far as years after. Individuals with addictions are at higher risk of multimorbidity and mortality during COVID outbreak.

CONCLUSION

This review describes useful strategies in clinical practice, including a systematic assessment of addiction comorbidity during this almost worldwide lockdown/pandemic. This review also highlights important areas for future research.

Neurobiochemical Cross-talk Between COVID-19 and Alzheimer's Disease

COVID-19, the global threat to humanity, shares etiological cofactors with multiple diseases including Alzheimer's disease (AD). Understanding the common links between COVID-19 and AD would harness strategizing therapeutic approaches against both. Considering the urgency of formulating COVID-19 medication, its AD association and manifestations have been reviewed here, putting emphasis on memory and learning disruption. COVID-19 and AD share common links with respect to angiotensin-converting enzyme 2 (ACE2) receptors and pro-inflammatory markers such as interleukin-1 (IL-1), IL-6, cytoskeleton-associated protein 4 (CKAP4), galectin-9 (GAL-9 or Gal-9), and APOE4 allele. Common etiological factors and common manifestations described in this review would aid in developing therapeutic strategies for both COVID-19 and AD and thus impact on eradicating the ongoing global threat. Thus, people suffering from COVID-19 or who have come round of it as well as people at risk of developing AD or already suffering from AD, would be benefitted.

Are smokers protected against SARS-CoV-2 infection (COVID-19)? The origins of the myth

A number of recent studies have found low percentages of smokers among COVID-19 patients, causing scientists to conclude that smokers may be protected against SARS-CoV-2 infection. National and international media were interested in this story and we soon began receiving questions about this topic in general practice. In this article, we shed light on the process that resulted in the misinterpretation of observational research by scientists and the media. We also point out the methodological flaws of various studies on which hasty conclusions were based. Finally, we address the role of primary healthcare providers in mitigating the consequences of erroneous claims about a protective effect of smoking.

Smoking and COVID-19: A Scoping Review

Smoking affects a person’s overall health and damages nearly every organ of the body. Since smoking tobacco affects and damages the lungs, it increases the risk of respiratory infections and makes it easier for the coronavirus disease (COVID-19) to invade the lung tissue, causing more severe symptoms and increasing the risk of death. However, debates are still ongoing as to the effect of cigarette smoking on vulnerability to COVID-19. Some studies, where active smokers were underrepresented among patients with COVID-19, claimed that a “smoker’s paradox” may exist in COVID-19 and that smokers are protected from infection and severe complications of COVID-19. However, other studies reported the opposite trend. The objective of this study is to review the findings of epidemiological and in vitro studies about the association between smoking and the risk of contracting COVID-19, taking into account disease severity. Several epidemiological studies have found a higher smoking prevalence among COVID-19 infected patients. Also, studies had shown that people with respiratory diseases caused by tobacco use are at higher risk of developing severe COVID-19 symptoms. Studies have shown that in vitro, the acute exposure allows for more severe proximal airway epithelial disease from SARS-CoV-2 by reducing the mucosal innate immune response and the proliferation of airway basal stem cells and has implications for disease spread and severity in people exposed to cigarette smoke, with a more severe viral infection and cell death. Smoker patients with different comorbidities are at higher risk of contracting the COVID-19 virus and have a worse prognosis for the virus as well as for their comorbidities. Further investigations of the interaction between smoking and COVID-19 are warranted to accurately assess the risk of contracting COVID-19 among smokers, and the progression to mechanical ventilation or death in patients who suffer from it.

The broad spectrum host-directed agent ivermectin as an antiviral for SARS-CoV-2 ?

FDA approved for parasitic indications, the small molecule ivermectin has been the focus of growing attention in the last 8 years due to its potential as an antiviral. We first identified ivermectin in a high throughput compound library screen as an agent potently able to inhibit recognition of the nuclear localizing Human Immunodeficiency Virus-1 (HIV-1) integrase protein by the host importin (IMP) α/β1 heterodimer, and recently demonstrated its ability to bind directly to IMPα to cause conformational changes that prevent its function in nuclear import of key viral as well as host proteins. Cell culture experiments have shown robust antiviral action towards a whole range of viruses, including HIV-1, dengue, Zika and West Nile Virus, Venezuelan equine encephalitis virus, Chikungunya, pseudorabies virus, adenovirus, and SARS-CoV-2 (COVID-19). Close to 70 clinical trials are currently in progress worldwide for SARS-CoV-2. Although few of these studies have been completed, the results that are available, as well as those from observational/retrospective studies, indicate clinical benefit. Here we discuss the case for ivermectin as a host-directed broad-spectrum antiviral agent, including for SARS-CoV-2.

Nicotinic Acetylcholine Receptor Involvement in Inflammatory Bowel Disease and Interactions with Gut Microbiota

The gut-brain axis describes a complex interplay between the central nervous system and organs of the gastrointestinal tract. Sensory neurons of dorsal root and nodose ganglia, neurons of the autonomic nervous system, and immune cells collect and relay information about the status of the gut to the brain. A critical component in this bi-directional communication system is the vagus nerve which is essential for coordinating the immune system’s response to the activities of commensal bacteria in the gut and to pathogenic strains and their toxins. Local control of gut function is provided by networks of neurons in the enteric nervous system also called the ‘gut-brain’. One element common to all of these gut-brain systems is the expression of nicotinic acetylcholine receptors. These ligand-gated ion channels serve myriad roles in the gut-brain axis including mediating fast synaptic transmission between autonomic pre- and postganglionic neurons, modulation of neurotransmitter release from peripheral sensory and enteric neurons, and modulation of cytokine release from immune cells. Here we review the role of nicotinic receptors in the gut-brain axis with a focus on the interplay of these receptors with the gut microbiome and their involvement in dysregulation of gut function and inflammatory bowel diseases.

Lower values of a novel index of Vagal-Neuroimmunomodulation are associated to higher all-cause mortality in two large general population samples with 18 year follow up

In recent clinical practice, a biomarker of vagal neuroimmunomodulation (NIM), namely the ratio of vagally-mediated heart rate variability (vmHRV) and CRP, was proposed to index the functionality of the cholinergic anti-inflammatory pathway. This study aims to transfer and extend the previous findings to two general population-based samples to explore the hypothesis that NIM-ratio is associated with all-cause mortality. Two large population studies (MIDUS 2: N = 1255 and Whitehall II wave 5: N = 7870) with complete data from a total of N = 3860 participants (36.1% females; average age = 56.3 years; 11.1% deaths, last exit 18.1 years post inclusion) were available. NIM indices were calculated using the vagally-mediated HRV measure RMSSD divided by measures of CRP (NIMCRP) or IL-6 (NIMIL6). The NIM-ratios were quartiled and entered into age, ethnicity and body mass index adjusted Cox proportional hazards models. For NIMIL6 the lowest quartile was 45% more likely to die during the observed period (max. 18 years follow-up) compared to the highest quartile (HR = 0.55 CI 0.41-0.73; p < .0001). NIMCRP parallel these results. Here we show that an easily computable index of IL-6 inhibition is associated with all-cause mortality in two large general population samples. These results suggest that this index might be useful for risk stratification and warrant further examination.

Smoking and COVID-19: A Literature Review of Cohort Studies in Non-Chinese Population Settings

BACKGROUND

Smoking history and its potential association with COVID-19 has attracted many researchers and the lay public alike. However, the studies published to date have several methodological limitations and are mainly from China. We set out to synthesize evidence on smoking and COVID-19 relationship drawn on cohort studies only which are published in non-Chinese population settings.

METHOD

A systematic literature search was undertaken drawn on predefined eligibility criteria and a comprehensive search strategy following the PRISMA guideline between January 2020 and August 2020, excluding preprints and gray literature. Three specific outcomes were examined: smoking history, SARS-CoV2 infection, and COVID-19 severity.

RESULTS

Of an eligible 40 full-text studies, 7 cohort studies outside of China were finally included in this literature review through independent reviewing. Four studies were from the UK, 2 from the United States, and 1 from Turkey. The sample size ranged from 200 to more than 5000 participants. The findings broadly point to 1 direction, a higher smoking prevalence and an increased risk of smoking history on both SARS-CoV2 infection and on COVID-19 severity.

CONCLUSION

A smoking history (either current or past) seems to negatively impact both SARS-CoV2 infection and COVID-19 severity. However, such an observation strengthens the argument to continue smoking cessation efforts both for individuals and for the general population health and well-being.

Tobacco Products and the Risks of SARS-CoV-2 Infection and COVID-19

Implications: This commentary addresses the state of the evidence on tobacco products, nicotine, and COVID-19. The evidence of the effects of smoking on respiratory infections and the immune system in general are examined and the current understanding of tobacco products and risk for SARS-CoV-2 infection and the course of COVID-19 is addressed.

Nicotine Changes Airway Epithelial Phenotype and May Increase the SARS-COV-2 Infection Severity

(1) Background: Nicotine is implicated in the SARS-COV-2 infection through activation of the α7-nAChR and over-expression of ACE2. Our objective was to clarify the role of nicotine in SARS-CoV-2 infection exploring its molecular and cellular activity. (2) Methods: HBEpC or si-mRNA-α7-HBEpC were treated for 1 h, 48 h or continuously with 10-7 M nicotine, a concentration mimicking human exposure to a cigarette. Cell viability and proliferation were evaluated by trypan blue dye exclusion and cell counting, migration by cell migration assay, senescence by SA-β-Gal activity, and anchorage-independent growth by cloning in soft agar. Expression of Ki67, p53/phospho-p53, VEGF, EGFR/pEGFR, phospho-p38, intracellular Ca2+, ATP and EMT were evaluated by ELISA and/or Western blotting. (3) Results: nicotine induced through α7-nAChR (i) increase in cell viability, (ii) cell proliferation, (iii) Ki67 over-expression, (iv) phospho-p38 up-regulation, (v) EGFR/pEGFR over-expression, (vi) increase in basal Ca2+ concentration, (vii) reduction of ATP production, (viii) decreased level of p53/phospho-p53, (ix) delayed senescence, (x) VEGF increase, (xi) EMT and consequent (xii) enhanced migration, and (xiii) ability to grow independently of the substrate. (4) Conclusions: Based on our results and on evidence showing that nicotine potentiates viral infection, it is likely that nicotine is involved in SARS-CoV-2 infection and severity.

Humidified Warmed CO2 Treatment Therapy Strategies Can Save Lives With Mitigation and Suppression of SARS-CoV-2 Infection: An Evidence Review

The coronavirus disease (COVID-19) outbreak has presented enormous challenges for healthcare, societal, and economic systems worldwide. There is an urgent global need for a universal vaccine to cover all SARS-CoV-2 mutant strains to stop the current COVID-19 pandemic and the threat of an inevitable second wave of coronavirus. Carbon dioxide is safe and superior antimicrobial, which suggests it should be effective against coronaviruses and mutants thereof. Depending on the therapeutic regime, CO2 could also ameliorate other COVID-19 symptoms as it has also been reported to have antioxidant, anti-inflammation, anti-cytokine effects, and to stimulate the human immune system. Moreover, CO2 has beneficial effects on respiratory physiology, cardiovascular health, and human nervous systems. This article reviews the rationale of early treatment by inhaling safe doses of warmed humidified CO2 gas, either alone or as a carrier gas to deliver other inhaled drugs may help save lives by suppressing SARS-CoV-2 infections and excessive inflammatory responses. We suggest testing this somewhat counter-intuitive, but low tech and safe intervention for its suitability as a preventive measure and treatment against COVID-19. Overall, development and evaluation of this therapy now may provide a safe and economical tool for use not only during the current pandemic but also for any future outbreaks of respiratory diseases and related conditions.

Influence of prior comorbidities and chronic medications use on the risk of COVID-19 in adults: a population-based cohort study in Tarragona, Spain

OBJECTIVE

To investigate possible relationships between pre-existing medical conditions (including common comorbidities and chronic medications) and risk for suffering COVID-19 disease in middle-aged and older adults.

DESIGN

Population-based retrospective cohort study.

SETTING

Twelve primary care centres (PCCs) in Tarragona (Spain).

PARTICIPANTS

79 083 people (77 676 community-dwelling and 1407 nursing-home residents), who were all individuals aged >50 years affiliated to the 12 participating PCCs.

OUTCOMES

Baseline cohort characteristics (age, sex, vaccinations, comorbidities and chronic medications) were established at study start (1st. March 2020) and primary outcome was time to COVID-19 confirmed by PCR among cohort members throughout the epidemic period (from 1st. March 2020 to 23rd. May 2020). Risk for suffering COVID-19 was evaluated by Cox regression, estimating multivariable HRs adjusted for age, sex, comorbidities and medications use.

RESULTS

During the study period, 2324 cohort members were PCR-tested, with 1944 negative and 380 positive results, which means an incidence of 480.5 PCR-confirmed COVID-19 cases per 100 000 persons-period. Assessing the total study cohort, only age (HR 1.02; 95% CI 1.01 to 1.03; p=0.002), nursing-home residence (HR 21.83; 95% CI 16.66 to 28.61; p<0.001) and receiving diuretics (HR 1.35; 95% CI 1.04 to 1.76; p=0.026) appeared independently associated with increased risk. Smoking (HR 0.62; 95% CI 0.41 to 0.93; p=0.022), ACE inhibitors (HR 0.68; 95% CI 0.47 to 0.99; p=0.046) and antihistamine (HR 0.47; 95% CI 0.22 to 1.01; p=0.052) were associated with a lower risk. Among community-dwelling individuals, cancer (HR 1.52; 95% CI 1.03 to 2.24; p=0.035), chronic respiratory disease (HR 1.82; 95% CI 1.08 to 3.07; p=0.025) and cardiac disease (HR 1.53; 95% CI 1.06 to 2.19; p=0.021) emerged to be also associated with an increased risk. Receiving ACE inhibitors (HR 0.66; 95% CI 0.44 to 0.99; p=0.046) and influenza vaccination (HR 0.63; 95% CI 0.44 to 0.91; p=0.012) was associated with decreased risk.

CONCLUSION

Age, nursing-home residence and multiple comorbidities appear predisposing for COVID-19. Conversely, receiving ACE inhibitors, antihistamine and influenza vaccination could be protective, which should be closely investigated in further studies specifically focused on these concerns.

Mini-review: antibody therapeutics targeting G protein-coupled receptors and ion channels

Antibodies are now well established as therapeutics with many additional advantages over small molecules and peptides relative to their selectivity, bioavailability, half-life and effector function. Major classes of membrane-associated protein targets include G protein-coupled receptors (GPCRs) and ion channels that are linked to a wide range of disease indications across all therapeutic areas. This mini-review summarizes the antibody target landscape for both GPCRs and ion channels as well as current progress in the respective research and development pipelines with some example case studies highlighted from clinical studies, including those being evaluated for the treatment of symptoms in COVID-19 infection.

Tobacco and COVID-19: a crisis within a crisis?

During the pandemic, the world's media have publicized preliminary findings suggesting that tobacco use is protective against COVID-19. An ad hoc multidisciplinary group was created to address the major public health implications of this messaging. Key messages of this commentary are as follows: 1) The COVID-19 crisis may increase tobacco consumption and decrease access to healthcare. As a result, smoking-related morbidity and mortality could increase in the coming months and years; 2) Smoking and tobacco-related diseases are prognostic factors for severe COVID-19; and 3) In theory, smokers may be at lower risk of COVID-19 infection because of having fewer social contacts. In conclusion, tobacco control is a greater challenge than ever in the context of the COVID-19 pandemic. Public decision-makers must be vigilant in ensuring that public health practices are consistent and compliant with the principles of the WHO Framework Convention on Tobacco Control. In addition, researchers and the media have a responsibility to be cautious in communicating preliminary results that may promote non-evidence-based research, self-destructive individual behaviours, and commercial agendas.

Autonomic balance determines the severity of COVID-19 courses

COVID-19 has left mankind desperately seeking how to manage dramatically rising infection rates associated with severe disease progressions. COVID-19 courses range from mild symptoms up to multiple organ failure and death, triggered by excessively high serum cytokine levels (IL 1β, IL 6, TNF α, IL 8). The vagally driven cholinergic anti-inflammatory pathway (CAP) stops the action of nuclear factor κB (NF-κB), the transcriptional factor of pro-inflammatory cytokines. Thus, well-balanced cytokine release depends on adequate vagal signaling. Coronaviruses replicate using NF-κB transcriptional factor as well. By degrading the cytoplasmatic inhibitor of NF-κB subunits (IκB), coronaviruses induce unrestricted NF-κB expression accelerating both, virus replication and cytokine transcription.We hypothesize that CAP detriment due to depressed vagal tone critically determines the severity of COVID-19.

Macrophage responses associated with COVID-19: A pharmacological perspective

COVID-19 has caused worldwide death and economic destruction. The pandemic is the result of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has demonstrated high rates of infectivity leading to great morbidity and mortality in vulnerable populations. At present, scientists are exploring various approaches to curb this pandemic and alleviate its health consequences, while racing to develop a vaccine. A particularly insidious aspect of COVID-19 is the delayed overactivation of the body's immune system that is manifested as the cytokine storm. This unbridled production of pro-inflammatory cytokines and chemokines can directly or indirectly cause massive organ damage and failure. Systemic vascular endothelial inflammation and thrombocytopenia are potential consequences as well. In the case of COVID-19, the cytokine storm often fits the pattern of the macrophage activation syndrome with lymphocytopenia. The basis for the imbalance between the innate and adaptive immune systems is not clearly defined, but highlights the effect of SARS-CoV-2 on macrophages. Here we discuss the potential underlying basis for the impact of SARS-CoV-2 on macrophages, both direct and indirect, and potential therapeutic targets. These include granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 6 (IL-6), interferons, and CXCL10 (IP-10). Various biopharmaceuticals are being repurposed to target the cytokine storm in COVID-19 patients. In addition, we discuss the rationale for activating the macrophage alpha 7 nicotinic receptors as a therapeutic target. A better understanding of the molecular consequences of SARS-CoV-2 infection of macrophages could lead to novel and more effective treatments for COVID-19.