If dual use of cigarettes and e-cigarettes is a transition state to tobacco and nicotine use cessation, it may be a tolerable temporary condition. But, if a long-term behavior, dual use may increase tobacco harm to the population as a whole, and efforts should aim to reduce it as much as possible. To develop effective tobacco control policy, the changes in dual use of e-cigarettes and cigarettes need to be better understood. National probability samples of U.S. adults in 2015 (n = 6051), 2016 (n = 6014), 2017 (n = 5992), and 2018 (n = 5989) reported their smoking and e-cigarette use status, including frequency of use. Weighted multinomial logistic regression models were used to examine temporal trends and patterns of cigarette and e-cigarette use. Between 2015 and 2018, the prevalence of current e-cigarette use (29.8% in 2015, 22.3% in 2016, 29.1% in 2017, and 27.7% in 2018) did not change significantly among current smokers. This result was consistent among light, moderate, and heavy smokers, and did not change when stratified by sex, age and race. However, the prevalence of cigarette smoking in current e-cigarette users declined from 56.9% in 2015 to 40.8% in 2018 (p < 0.001). Among never (p = .012) and former (ps < 0.001) smokers the prevalence of current e-cigarette use increased significantly. The continued high prevalence of dual use and increased prevalence of current e-cigarette use among never smokers highlight the need for better communication about the risks of prolonged dual use for e-cigarette users, and the risks of nicotine initiation and addiction for nonusers.

Background: To better understand severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shedding and infectivity, we estimated SARS-CoV-2 RNA shedding duration, described participant characteristics associated with the first negative rRT-PCR test (resolution), and determined if replication-competent viruses was recoverable ≥10 days after symptom onset. Methods: We collected serial nasopharyngeal specimens from 109 individuals with rRT-PCR–confirmed COVID-19 in Utah and Wisconsin. We calculated viral RNA shedding resolution probability using the Kaplan-Meier estimator and evaluated characteristics associated with shedding resolution using Cox proportional hazards regression. We attempted viral culture for 35 rRT-PCR–positive nasopharyngeal specimens collected ≥10 days after symptom onset. Results: The likelihood of viral RNA shedding resolution at 10 days after symptom onset was approximately 3%. Time to shedding resolution was shorter among participants aged <18 years (adjusted hazards ratio [aHR], 3.01; 95% confidence interval [CI], 1.6–5.6) and longer among those aged ≥50 years (aHR, 0.50; 95% CI, .3–.9) compared to participants aged 18–49 years. No replication-competent viruses were recovered. Conclusions: Although most patients were positive for SARS-CoV-2 for ≥10 days after symptom onset, our findings suggest that individuals with mild to moderate COVID-19 are unlikely to be infectious ≥10 days after symptom onset.

Tobacco companies argue that the decision to smoke is made by well-informed rational adults who have considered all the risks and benefits of smoking. Yet in promoting their products, the tobacco industry frequently relies on affect, portraying their products as part of a desirable lifestyle. Research examining the roles of affect and perceived risks in smoking has been scant and non-existent for novel tobacco products, such as electronic cigarettes (e-cigarettes). We examined the relationship between affect, perceived risk, and current use for cigarettes and e-cigarettes in 2015 in a nationally representative sample of 5398 U.S. adults who were aware of e-cigarettes. Participants held various affective associations with tobacco products, and affect towards cigarettes was more negative than affect towards e-cigarettes. Using structural equation modeling (SEM), affect towards cigarettes and e-cigarettes was associated with cigarette smoking and e-cigarette use respectively, and these associations were both direct and partially mediated by risk perceptions towards smoking and e-cigarette use. More positive affect towards cigarettes or e-cigarettes was associated with lower perceived risks, which in turn was associated with higher odds of being a current cigarette or e-cigarette user. In developing models explaining tobacco use behavior, or in creating public communication campaigns aimed at curbing tobacco use, it is useful to focus not only on the reason based predictors, such as perceptions of risks and benefits, but also on affective predictors. Educational efforts aimed at further smoking reductions should highlight and reinforce negative images and associations with cigarettes.

Introduction Health agencies are grappling with communicating risks of electronic cigarettes (e-cigarettes) compared with combusted cigarettes. This study examined smokers’ responses to two types of comparative risk messages with one type incorporating more negative antismoking elements in the design. Methods In an online experiment, 1400 US adult (18+ years) current smokers and recent quitters were randomised to view one of three comparative risk messages about e-cigarettes (CR messages), one of three comparative risk messages that included more negative antismoking elements in the design (CR− messages) or a control message. Selection of outcomes was guided by the antismoking message impact framework. Multivariate analyses of covariance and logistic regression models analysed effects of messages on message evaluations, e-cigarette-related and cigarette-related beliefs and behavioural intentions. Results Both CR and CR− messages decreased smokers’ intentions to smoke cigarettes, increased intentions to switch to e-cigarettes completely and increased perceptions that e-cigarettes are less harmful than combusted cigarettes. Neither message type increased dual use intentions relative to exclusive e-cigarettes use or smoking cessation. CR messages decreased perceived absolute risks of e-cigarettes and self-exempting beliefs about smoking, whereas CR− versus CR messages produced higher self-efficacy to quit smoking. Conclusion Comparative risk communication might encourage smokers to switch to lower-harm tobacco products. Comparative risk messages with more negative antismoking elements in the design might be particularly effective, because they led to higher self-efficacy to quit smoking. Regulatory agencies may consider using comparative risk messages with more negative antismoking elements to educate the public about lower risk of e-cigarettes.

Background In reviewing the first set of pictorial warning labels in the USA, the courts equated textual labels with facts and information, and images with emotion. This study tested the differences in perceived informativeness and emotion between textual and pictorial cigarette warning labels. Methods An online study with 1838 US adults who were non-smokers (n=764), transitioning smokers (quit smoking in the past 2 years or currently trying to quit, n=505) or current smokers (n=569). Each participant evaluated 9 out of 81 text and pictorial cigarette warning labels. Participants reported to what extent they perceived the label as informative and factual and the negative emotions they felt while looking at each label. We used linear mixed models to account for the nesting of multiple observations within each participant. Results There were no significant differences in perceived informativeness between textual (mean 6.15 on a 9-point scale) and pictorial labels (6.14, p=0.80, Cohen’s d=0.003). Textual labels evoked slightly less emotion (4.21 on a 9-point scale) than pictorial labels (4.42, p<0.001, Cohen’s d=0.08). Perceived informativeness and emotion were strongly correlated (Pearson r=0.53, p<0.001). Conclusion Our findings contradict courts’ conclusions that pictorial messages are emotional and not factual. Pictorial labels are rated as informative and factual, textual labels evoke emotion, and emotionality and informativeness are strongly correlated. These findings serve as evidence for the Food and Drug Administration (FDA) to counteract the claim that pictorial warning labels, by definition, are not ‘purely factual and uncontroversial’.