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 Table of Contents  
Year : 2021  |  Volume : 33  |  Issue : 1  |  Page : 82-90

Tobacco cessation is a challenge during COVID-19 pandemic: Is it a good time to quit?: A systematic review

1 Department of Oral Medicine and Radiology, Swami Devi Dyal Hospital and Dental College, Panchkula, Haryana, India
2 Department of Oral Medicine and Radiology, Faculty of Dental Sciences, Ramaiah University of Applied Sciences, Bengaluru, Karnataka, India
3 Department of Oral Medicine and Radiology, RR Dental College and Hospital, Udaipur, Rajasthan, India

Date of Submission13-Jul-2020
Date of Decision10-Dec-2020
Date of Acceptance31-Dec-2020
Date of Web Publication26-Mar-2021

Correspondence Address:
Dr. Ravleen Nagi
Department of Oral Medicine and Radiology, Swami Devi Dyal Hospital and Dental College, Panchkula, Haryana
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jiaomr.jiaomr_132_20

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Introduction: COVID-19 is a global health crisis experienced ever, caused by novel severe acute respiratory syndrome coronavirus-2 (SARS CoV -2); unfortunately, this pandemic is still progressing, affecting over millions of people worldwide. Evidences have revealed that psychological stress experienced during pandemic is making tobacco users more addictive, therefore to prevent especially youth from harmful effects of tobacco, tobacco cessation is the need of the hour. Aim: The aim of this systematic review was to compile evidence-based studies pertaining to tobacco use during COVID-19 pandemic and highlighting the challenges incurred towards successful quit attempts by the tobacco user. Materials and Method: Computerized literature search was performed from December 2019 till June 2020 to select eligible articles from the following databases: PUBMED [MEDLINE], SCOPUS, SCIENCE DIRECT, and COCHRANE DATABASE using specific keywords. The search was limited to articles published as full text in English, which were screened by two reviewers for eligibility. Results: Six studies satisfied our inclusion criteria. Two studies found that tobacco users have achieved successful quitting during lockdown period, and contrary to this three studies suggested that users have become more addictive to smoking due to psychological stress experienced during pandemic. One study suggested current smokers to be higher risk of acquisition of severe disease. Conclusion: Oral physicians should extend extra support to tobacco users to quit by brief or moderate interventions by means of telephonic consultation or video conferencing during this pandemic. In future more studies should be conducted to understand the effect of pandemic on tobacco use pattern.

Keywords: Challenge, COVID-19, intervention, nicotine, SARS-CoV-2, tobacco

How to cite this article:
Nagi R, Reddy SS, Rakesh N, Vyas T. Tobacco cessation is a challenge during COVID-19 pandemic: Is it a good time to quit?: A systematic review. J Indian Acad Oral Med Radiol 2021;33:82-90

How to cite this URL:
Nagi R, Reddy SS, Rakesh N, Vyas T. Tobacco cessation is a challenge during COVID-19 pandemic: Is it a good time to quit?: A systematic review. J Indian Acad Oral Med Radiol [serial online] 2021 [cited 2022 Jan 27];33:82-90. Available from: https://www.jiaomr.in/text.asp?2021/33/1/82/312194

   Introduction Top

COVID-19 is a major global outbreak characterized by mild-to-severe respiratory illness, caused by novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS CoV-2). It has spread all over the globe since its origin in Wuhan, China in December 2019 and has been declared as worst pandemic experienced ever.[1] Transmission occurs mostly via inhalation of suspended airborne or droplet particles that enter the respiratory tract of a person, touching of contaminated surfaces and then touching of mouth or nose.[2],[3] Tobacco use in both smoke and smokeless forms during pandemic has become a major concern; evidence has shown smokers to be at higher risk to suffer from severe symptoms and complications of COVID-19 infection; that is Acute Respiratory Distress Syndrome (ARDS) and Multiorgan Failure.[4],[5]

Global Adult Tobacco Survey (GATS) II survey reports of 2016-17 have revealed that level of tobacco usage is high in India, and 59% of adults consume tobacco within 30 minutes of waking up.[6] Daily cigarette smoking has been reported to be 6% in comparison to bidi smoking which is 10%. In India consumption of Smokeless Tobacco (SLT) by chewing, applying it directly to gums or by sniffing is more commonly practiced; of 26% adults, 21% use it daily and remaining 5% use occasionally. Increase in use of tobacco products among young children and adolescents during lockdown period to reduce anxiety has become a rising concern[6] Oral physicians play a crucial role in extending awareness about deleterious effects of tobacco usage on both oral and systemic health and in providing help and support to tobacco users willing to make quit attempts during pandemic. The aim of this systematic review was to evaluate literature regarding effect of ongoing pandemic on the tobacco cessation and emphasizes the need to provide behavioral support to tobacco users.

   Method Top

Literature search

A systematic review of scientific literature regarding effect of COVID-19 pandemic on tobacco use both in smoke and smokeless forms and attempts towards successful tobacco cessation was done in the manuscript. The electronic retrieval systems and databases such as PubMed (Medline), SCOPUS, Science Direct, and Cochrane DATABASE were searched for relevant articles from December 2019 till November June 2020, interrogated by MeSH terms. The MeSH terms used to evaluate the association of tobacco use and COVID-19 pandemic were “tobacco”, “nicotine”, “ COVID-19”, “SARS-CoV-2”, “challenge “ and “intervention”. Randomized controlled trials, single and double-blinded trials, cross-sectional and case-control studies published as full text in English Language were included in this review. Exclusion criteria were: in vitro studies, review articles, case reports and which were not focusing on the tobacco use during COVID-19 pandemic.

[Table 1] shows that the initial computerized search strategy yielded 602 titles. In the first selection two reviewers with ten years' experience in the field, screened the articles by reading titles and abstracts of the retrieved publications and 530 were discarded because these articles did not fulfill the inclusion criteria. Any conflicting views were resolved by mutual discussion between reviewers. Out of those 530 articles, 412 were excluded as these were case reports, review articles, and in vitro studies. Remaining 72 articles that fulfilled the eligibility criteria were read in full. Among these 72 articles, 66 were excluded due to lack of demographic data and discrepancy in outcome, only 6 studies met our inclusion criteria. Later, each reviewer performed screening of eligible articles individually and tried to obtain the full text of final eligible studies for this systematic review.
Table 1: Preferred reporting items for systematic review (PRISMA) diagram showing article selection for tobacco (smoke/smokeless form) use during COVID-19 pandemic

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Data extraction

On the basis of studies characteristics (title of the paper, author's information, year of study, aim and objectives, outcome, and conclusion) two reviewers independently extracted data using the standard data extraction form. Studies focusing on the association of tobacco use and challenges faced by the users towards making quit attempts were analyzed for bias by the reviewers. Differences between the reviewers were sorted out by mutual discussion.

   Results Top

[Table 2] summarizes six eligible studies from preexisting literature pertaining to tobacco use in both smoke and smokeless form and risk of COVID-19. Three studies by Gaiha MS et al.,[7] Vanderbruggen N et al.,[8] and Kowitt SD et al.[9] suggested that smoking tobacco products that includes e-cigarettes, normal cigarettes and cigars have resulted in increased risk of COVID -19 infection and users have become more addictive to smoking during lockdown which may be due to boredom, loneliness, social isolation, and hard work all day during pandemic. Contrary to their findings, Paleiron N et al.[10] found lower risk for current smokers becoming infected than non-smokers and ex-smokers (p = 0.001) and they concluded that current smokers could be less susceptible to the SARS-CoV-2. However, once infected, current smokers are at risk of acquisition of severe disease. When attempt to quit tobacco during pandemic was analyzed, study by Gupta HA et al.[11] stated that of 219 (34%) tobacco users who had quit tobacco during the lockdown, 51% quit because of the lockdown and their concern over COVID-19 and abstinence rates were more among the users who were well aware of association between tobacco use and SARS-CoV-2. Tetik BK et al.[12] found 31.1% rate of smoking cessation during the pandemic period and according to them, increase in rate of smoking cessation might be due to the fear of risk of COVID-19 infection due to smoking.
Table 2: Summary of studies from preexisting literature pertaining to tobacco use (smoke/smokeless form) and its cessation during COVID-19 pandemic

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By our analysis of six studies, there are two schools of thought, firstly Gupta HA et al.[11] and Tetik BK et al.[12] observed that tobacco users have achieved successful quitting during lockdown period, and contrary to this cross-sectional studies by Gaiha MS et al.,[7] Vanderbruggen N et al.,[8] and Kowitt SD et al.[9] suggested that users have become more addictive to smoking due to psychological stress experienced during pandemic. Therefore, more research is needed to understand the effect of pandemic on tobacco use pattern. Future cessation studies should consider risk of tobacco use and COVID-19 during counseling sessions.

Risk of Bias Assessment across individual studies: [Table 3] shows that all studies demonstrated low-risk bias using COCHRANE BIAS TOOL. All studies showed low-risk bias for randomization, whereas high-risk bias was found for allocation concealment and blinding of participants. No inadequacy towards outcome data was observed for all studies.
Table 3: Risk of bias assessment across individual studies

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   Discussion Top

COVID-19 is a devastating global outbreak that has resulted in increased use of tobacco products in both smoke or smokeless forms. Studies have shown that SARS CoV-2 enter host cells via Angiotensin-Converting Enzyme 2 (ACE) receptors that are abundantly present in the lung alveolar tissues.[13],[14] ACE 2 levels and furin, the protein convertase, have been found to be upregulated in lungs of chronic smokers and are at an increased risk of COVID-19 infection.[15] Survey done in China has found that smokers are 14 times more likely to develop severe respiratory pneumonia like illness than nonsmokers that is well explained by decrease in lung function, damage to immune system and increase of repetitive hand-to-face movements in smokers increases risk of virus entry into host cells.[14] Studies have reported effect of smoking on ACE 2 expression in the brain, that is nicotine can upregulate ACE2 expression to facilitate the entry of SARS-CoV-2 in neurons, resulting in several neurological and cerebrovascular complications.[15]

Various pathogenic mechanisms have been proposed to explain the effect of tobacco smoke on the lung tissues, Groskreutz et al.[16] hypothesized that cigarette smoke causes necrosis, prevents virus induced cellular apoptosis, increases activity of caspase 3 and 7 followed by activation of inhibitors of apoptosis. All these cellular events result in increased inflammation, and replication of virus. In a recent systematic review that comprised data from five studies, it was suggested that smokers have adverse disease outcomes, are 1.4 times more likely to manifest typical symptoms of COVID-19 i.e dry cough, fever, sore throat, muscle/joint pains, diarrhea and require more intensive care and ventilation than nonsmokers.[5] Scientific Data has found worsening of COVID-19 infection in hospitalized patients addictive to smoking, nicotine has been found to increase the expression of ACE-2, which in turn modulates the nicotine acetylcholine receptor.[17] Miyara et al.[18] assessed smoking status for symptomatic COVID-19 patients, and they suggested that smokers, both outpatient and hospitalized, should be counseled and need to be protected against COVID-19 infection [Figure 1] and [Figure 2]. Besides this, sharing of smoke tobacco devices hookah or water pipe, and cigarette lighters are associated with transmission of virus.[13]
Figure 1: Depicts potential deleterious effects of smoking during COVID-19 Pandemic and need of tobacco cessation

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Figure 2: Effect of tobacco use in both smoke and smokeless forms on COVID-19 risk

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Vaping, that is use of electronic (e-cigarettes) was considered as an alternative to normal cigarette smoking with less addictive potential. However, use of e-cigarettes has been banned in India and across 25 countries due to its widespread short- and long-term health risks, and its sale now requires market authorization. Currently, reports have shown that vaping suppresses immune cells in the nose and destroys cilia in the lung to a greater extent thereby predisposing to respiratory infections.[17],[18] Few studies have reported that coronavirus gets dispersed with particles in second-hand smoke and aerosols produced by vaping of e cigarettes reside on environmental surfaces for days.[5] Spread of corona infection by vape clouds is questionable, as it has been found that vaping aerosol evaporates very readily whereas infectious particles emitted on coughing or sneezing remain dispersed in air for longer duration. In other words, when someone smokes or vapes, he or she breathes out respiratory droplets and if the smoker is symptomatic for infection then nearby person in close proximity is at higher risk of getting respiratory infection. Therefore, prolonged exposure to secondhand smoke increases risk of lung damage and subsequent coronavirus complications.[5]

Besides smoking, SLT is a group of unburnt tobacco products containing nicotine and is highly addictive. According to GATS survey 2016-17, in India 21.4% of population uses SLT products, and most commonly used SLT includes khaini, gutka, betel quid with tobacco and zarda. In India, habit of SLT use is more prevalent in men of lower socioeconomic dwellings and urban slums, and users have increased salivary production with an urge to spit it out in public places.[19] When the symptomatic patient spits, viral particles present in the saliva or droplets are dispersed in the air and they become a huge threat for the population within the sphere.[20] This is an emerging concern in both developing and developed countries; according to American Lung Association; 9.6% high-school and 3.1% middle-school students are addicted to tobacco products, including SLT and spit it out at public areas.[21]

SLT users have been reported to have increase susceptibility to COVID -19 due to increase of viral tropism in the oral mucosa (tongue), and altered immune response. Higher expression of ACE 2 receptors in oral epithelial cells of tongue, buccal mucosa, gingiva and minor salivary glands favors viral tropism. Immunohistochemical studies have shown high expression of furin enzyme in the tongue and the presence of a furin-like cleavage site in the viral spike protein allows virus entry into the host cells.[20] Secondly, prolonged use of SLT products results in aberrant immune response against the virus, both adaptive and innate immune mechanisms are affected that results in release of prostaglandins and cytokines such as interleukin (IL)-6, interferon α, tumor necrosis factor, and transforming growth factor β, these all cellular events increases the likelihood of COVID-19 infection [Figure 3]. Moreover, urge to spit out in public places, sharing of SLT products and repetitive hand to mouth contact increases the risk of transmission of infection.[20]
Figure 3: Smokeless tobacco (SLT); altered immune response

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Tobacco use in form of smoking has been found to be detrimental to respiratory tissues, contrary to this, in another report it has been stated that smokers are 23% less likely to suffer from COVID-19 infection than non-smokers, which may be due to protective effects of nicotine that blocks the docking sites or entry of virus in the body through neurons in the olfactory cells or lung cells, but this hypothesis still remains unclear.[16] In our opinion, more evidence-based investigations are required to substantiate the association as most of the reported studies have focused on evaluation of smoking status in hospitalized patients with medical co morbidities. Over or under estimation of smoking status is also a subject of bias.

Coronavirus outbreak has drastically influenced the smoking habits of people, some are using pandemic period to quit, away from reach of tobacco products, whereas others are becoming more addictive to cope up with stress and anxiety experienced due to social isolation. Investigatory reports have revealed that it's harder to quit during the pandemic period as smokers are stuck at home, feel anxious, depressed, nervous and more fearful of acquiring infection. Gaiha MS et al.,[7] Vanderbruggen N et al.,[8] and Kowitt SD et al.[9] found that users have become more addictive to smoking due to psychological stress experienced during pandemic, hence all these factors forces smokers to suffer from nicotine addiction [Figure 4]. They quit for a week and then suffer from relapse; hence for successful quitting they need continuous support and help.
Figure 4: Vicious cycle of stress, COVID-19 pandemic and nicotine addiction

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Quitting tobacco is a necessity to restrict the spread of SARS-CoV-2 infection and for improvement of lung and cardiovascular efficiency of smokers, if infected. World Health Organization (WHO) recommends that smokers should make quit attempts by help of toll-free quit lines, tobacco cessation counselors and by use of nicotine replacement therapies (NRT) available as nicotine gums, lozenges, nicotine patches.[22],[23] WHO has recommended very brief intervention counselling sessions for about 3-5 minutes based on 5A's, that is Ask, Advise, Assess, Assist, and Arrange [Table 4].[23] Tobacco users find harder to quit due to peer pressure by friends, relatives, neighbours' etc., moreover this pandemic has resulted in lockdown across many countries, and self-isolation or quarantine with restricted outward movement. These regulatory measures are essential to reduce the spread of virus but have made people feel lonely and they succumb to use of tobacco products to relieve stress and anxiety.[6] During the pandemic, temporary ban on the sale of tobacco products was a measure adopted to reduce tobacco consumption in India, and users were made to stay without use of tobacco products for at least six weeks so that they can cope with the withdrawal symptoms. Many NRT may help in the withdrawal phase but most of them such as nicotine patches are expensive.[6] According to GATS survey, about 55% of smokers and 50% of smokeless tobacco users showed interest in quit plan and quit ratio for smokers was (16.8%) was higher than smokeless tobacco users (5.8%).[3]
Table 4: Very brief tobacco cessation intervention based on 5As (Ask, Advise, Assess, Assist, and Arrange)

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Recently introduced technology-based interventions such as mobile phones, web-based or smartphone apps aim at providing evidence-based tobacco cessation services to users. These apps allow tobacco users to opt for cessation advice, provides constant motivation to quit and maximizes the effect of pharmacotherapy and behavioral counselling. Besides this, educational videos shown to tobacco users by web-based video conferencing prevents relapse and abstain quitters from use of tobacco products.[24] Thus, telehealth services along with standard tobacco cessation protocol have limited the exposure among the patients and health professionals during COVID-19 pandemic and could increase the likelihood of successful quit attempts.


Use of NRT and behavioural counseling by physicians by means of telephone or video conferencing during the outbreak plays a key role in extending support to smokers/SLT tobacco users who are willing to quit.[3],[5] Incremental taxation regime, prohibition of spitting in public areas, standardized and validated testing of contents of SLT products, bans on illegal export between countries, display of pictorial warnings on packaging and prohibition of sale of these products to children and youth would contribute towards decrease in use of tobacco products and will slow down the spread of virus during pandemic.[21]

It is important during pandemic to extend public awareness through social media about harmful effects of tobacco use, to reduce their consumption, avoid sharing of tobacco products, frequent hand to mouth contact and public spitting. They should be educated to maintain optimal hand hygiene and practice precautionary measures, such as wearing of protective mouth mask, maintain physical distancing and use of alcohol-based hand sanitizers to reduce the incidence of community spread of virus. Telehealth has opened a new door for the users, most of them want to give addiction treatment a try due to more sharing and intimacy with the counsellor. They have been found to share their barriers in quitting process, and feel free to disclose psychiatric symptoms, or any drug abuse by digital communication than in person.[5] Counsellors can effectively reinforce brief intervention strategies based on 5A's (Ask, Assess, Advise, Assist, and Arrange) [Table 4].[5],[23] Thus, pandemic is changing lifestyle of people towards smoking or SLT use for better or worse.

Future prospects

  • More evidence-based trials on large scale should be conducted to validate the association of smoking or vaping with severity of COVID-19 infection, and recording of smoking or SLT use status should be necessarily done for the COVID-19 symptomatic patients. In addition, tobacco cessation counselling sessions should assess the awareness of user towards COVID-19 infection and they should emphasize the need for timely cessation.
  • Collection of saliva should be encouraged as a diagnostic tool in hospital settings for evaluation of COVID status of users due to its potential benefits of ease of collection and interpretation of initial infection
  • Laboratories should assess level of viral contamination in tobacco products such as waterpipes that are often shared between the users
  • Oral physicians should practice telemedicine during pandemic to assist users for timely tobacco cessation
  • Users should be advised to boost their immune system by regular physical exercise, yoga and meditation, that helps in relieving stress and reduces urge to use tobacco
  • Health experts have recommended consumption of vitamin rich diet ; that is 1000 mcg of Vitamin C couple of times a day and 50 mg of Zinc per day to strengthen immunity. Zinc, once inside the cells has been studied to stop the replication of virus. Inclusion of ayurvedic herbs such as tulsi, turmeric, cloves, cinnamon etc., have been found to enhance immune system to fight the virus.[25]

   Conclusion Top

Our analysis of studies used in this systematic review favors that tobacco cessation during pandemic is a necessity, vaping or smoking makes the individual vulnerable to COVID-19 infection that suppresses immune system, and delays recovery from severe pneumonia like symptoms. Lockdown and self-isolation have made people to use tobacco products to combat stress, therefore to prevent the spread, oral physicians should offer NRT and behavioural interventions, and quit lines should extend continuous support to users, to make successful quit attempts. Very brief interventions by telecommunication should be adopted to counsel the tobacco users especially in remote areas or declared as positive for COVID-19. Thus, pandemic is a teachable period for tobacco users to quit promptly and break the cycle of nicotine addiction.

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Conflicts of interest

There are no conflicts of interest.

   References Top

Li Q, Guan X, Wu P, Wang X, Zhou L, Tong Y, et al. Early transmission dynamics inWuhan, China, of novel coronavirus–infected pneumonia. N Eng J Med 2020;382:1199-207.  Back to cited text no. 1
Contini C, Di Nuzzo M, Barp N, Bonazza A, De Giorgio R, Tognon M, et al. The novel zoonotic COVID-19 pandemic: An expected global health concern. J Infect Dev Ctries 2020;14:254-64.  Back to cited text no. 2
Coulthard P. Dentistry and coronavirus (COVID -19)-Moral decision making. Br Dent J 2020;228:503-5.  Back to cited text no. 3
Arcavi L, Benowitz NL. Cigarette smoking and infection. Arch Intern Med 2004;164:2206-16.  Back to cited text no. 4
Vardavas CI, Nikitara K. COVID-19 and smoking: A systematic review of the evidence. Tob Induc Dis 2020;18:20.  Back to cited text no. 5
Wal A. Half of India's tobacco users try to quit but give up in a month, Now Gov Centres will help them. Available from: https://www.news18.com/. [Last accessed on 2020 Jun 07].  Back to cited text no. 6
Gaiha AS, Cheng J, Halpern-Felsher B. Association between youth smoking, electronic cigarette use, and COVID-19. J Adolesc Health 2020;67:519-23.  Back to cited text no. 7
Vanderbruggen N, Matthys F, Van Laere S, Zeeuws D, Santermans L, Van den Ameele S, et al. Self-reported alcohol, tobacco, and cannabis use during COVID-19 lockdown measures: Results from a web-based survey. Eur Addict Res 2020;26:309-15.  Back to cited text no. 8
Kowitt SD, Ross JC, Jarman KL, Kistler CE, Lazard AJ, Ranney LM. Tobacco quit intentions and behaviors among cigar smokers in the United States in response to COVID-19. Int J Environ Res Public Health 2020;17:5368.  Back to cited text no. 9
Paleiron N, Mayet A, Marbac V, Perrise A, Barazutti H, Barocq FX, et al. Tobacco smoking is associated with a lower risk of COVID-19. Lancet 2020. Available from: https://dx.doi.org/10.2139/ssrn0.3611963.  Back to cited text no. 10
Gupta AK, Nethan ST, Mehrotra R. Tobacco use as a well-recognized cause of severe COVID-19 manifestations. Respir Med 2021;176:106233.  Back to cited text no. 11
Tetik BK, Tekinemre IG, Tas S. The effect of the COVID-19 pandemic on smoking cessation success. J Community Health 2020. Available from: https://doi.org/10.1007/s10900-020-00880-2.  Back to cited text no. 12
Fini MB. Oral saliva and COVID-19. Oral Oncol 2020;108:104821. doi: 10.1016/j.oraloncology. 2020.104821.  Back to cited text no. 13
Strzelak A, Ratajczak A, Adamiec A, Feleszko W. Tobacco smoke induces and alters immune responses in the lung triggering inflammation, allergy, asthma and other lung diseases: A mechanistic review. Int J Environ Res Public Health 2018;15:1033.  Back to cited text no. 14
Sifat AE, Nozohouri S, Villalba H, Vaidya B, Abbriscato TJ. The role of smoking and nicotine in the transmission and pathogenesis of COVID-19. J Pharmacol Exp Ther 2020;375:498–509.  Back to cited text no. 15
Groskreutz DJ, Monick MM, Babor EC, Nyunoya T, Varga SM, Look DC, et al. Cigarette smoke alters respiratory syncytial virus-induced apoptosis and replication. Am J Respir Cell Mol Biol 2009;41:189-98.  Back to cited text no. 16
Liu W, Tao ZW, Wang L, Yuan ML, Liu K, Zhou L, et al. Analysis of factors associated with disease outcomes in hospitalized patients with 2019 novel coronavirus disease. Chin Med J (Engl) 2020;133:1032-8.  Back to cited text no. 17
Miyara M, Tubach F, Pourcher V, Morelot-Panzini C, Pernet J, Haroche J, et al. Low incidence of daily active tobacco smoking in patients with symptomatic COVID-19. 2020 Available from: https://www.qeios.com/read/WPP19W.3.  Back to cited text no. 18
Gaunkar RB, Nagarsekar A, Carvalho KM, Jodalli PS, Mascarenhans K. COVID-19 in smokeless tobacco habitués: Increased susceptibility and transmission. Cureus 2020;12:e8824.  Back to cited text no. 19
Legg TJ. Smoke or Vape? Here what you need to know about COVID-19 risks. Available from: https://www.healthline.com/. [Last accessed on 2020 Apr 07].  Back to cited text no. 20
Hefler M. Smokeless tobacco use and the COVID-19 pandemic. Available from: https://blogs.bmj.com/tc/2020/03/30/smokeless-tobacco-use-and-the-covid-19-pandemic/. [Last accessed on 2020 Mar 30].  Back to cited text no. 21
Elzas S. French researchers suggest nicotine could protect against coronavirus. Available from: https://www.rfi.fr/en/science. [Last accessed on 2020 Apr 23].  Back to cited text no. 22
World Health Organization. Toolkit for delivering the 5A's and 5R's brief tobacco interventions to TB patients in primary care. May, 2014.  Back to cited text no. 23
Ahluwalia IB, Myers M. COVID-19 pandemic an opportunity for tobacco use cessation. Lancet 2020;5:e577.  Back to cited text no. 24
Ayurvedic Institute. Ayurvedic perspective on COVID-19. Available from: https://www.ayurveda.com/ayurvedic-perspective-on-covid-19. [Last accessed on 2020 Jul 12].  Back to cited text no. 25


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

  [Table 1], [Table 2], [Table 3], [Table 4]


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