Electronic Nicotine-Delivery Systems for Smoking Cessation.

BACKGROUND: Electronic nicotine-delivery systems - also called e-cigarettes - are used by some tobacco smokers to assist with quitting. Evidence regarding the efficacy and safety of these systems is needed. METHODS: In this open-label, controlled trial, we randomly assigned adults who were smoking at least five tobacco cigarettes per day and who wanted to set a quit date to an intervention group, which received free e-cigarettes and e-liquids, standard-of-care smoking-cessation counseling, and optional (not free) nicotine-replacement therapy, or to a control group, which received standard counseling and a voucher, which they could use for any purpose, including nicotine-replacement therapy. The primary outcome was biochemically validated, continuous abstinence from smoking at 6 months. Secondary outcomes included participant-reported abstinence from tobacco and from any nicotine (including smoking, e-cigarettes, and nicotine-replacement therapy) at 6 months, respiratory symptoms, and serious adverse events. RESULTS: A total of 1246 participants underwent randomization; 622 participants were assigned to the intervention group, and 624 to the control group. The percentage of participants with validated continuous abstinence from tobacco smoking was 28.9% in the intervention group and 16.3% in the control group (relative risk, 1.77; 95% confidence interval, 1.43 to 2.20). The percentage of participants who abstained from smoking in the 7 days before the 6-month visit was 59.6% in the intervention group and 38.5% in the control group, but the percentage who abstained from any nicotine use was 20.1% in the intervention group and 33.7% in the control group. Serious adverse events occurred in 25 participants (4.0%) in the intervention group and in 31 (5.0%) in the control group; adverse events occurred in 272 participants (43.7%) and 229 participants (36.7%), respectively. CONCLUSIONS: The addition of e-cigarettes to standard smoking-cessation counseling resulted in greater abstinence from tobacco use among smokers than smoking-cessation counseling alone. (Funded by the Swiss National Science Foundation and others; ESTxENDS ClinicalTrials.gov number, NCT03589989.).

[Tobacco cessation treatment for people with schizophrenia]. / Traitement pharmacologique d'aide au sevrage tabagique chez les patients souffrant de schizophrénie.

Among patients suffering from schizophrenia, tobacco smoking prevalence is extremely high and represents a major burden in terms of morbidity and mortality. Tobacco smoking is under-diagnosed and under-treated by mental health professionals, mostly due to an overestimated risk of jeopardizing the patient's mental condition, but also due to a lack of expertise on tobacco cessation treatment. Despite the extent of this problem, pharmacological approaches haven't been studied enough. However, treatments such as varenicline, bupropion and nicotine replacement are effective and well tolerated and their prescription should be recommended for tobacco withdrawal among these patients.

La prévalence du tabagisme chez les patients souffrant de schizophrénie est extrêmement élevée et il constitue une charge majeure de morbidité et mortalité pour ces patients. Cependant, cette problématique reste sous-diagnostiquée et sous-traitée par les professionnels de santé mentale, notamment en raison d'une surestimation du risque de décompensation du trouble psychiatrique et par manque de compétences dans le domaine de la tabacologie. Malgré l'ampleur de la problématique, les approches pharmacologiques ont été peu étudiées pour cette population. Néanmoins, la prescription de traitements comme la varénicline, le bupropion et la substitution en nicotine, qui sont bien tolérés et efficaces, est recommandée pour l'aide au sevrage tabagique chez ces patients.

[Dyspepsia: a more complex approach]. / Dyspepsie: une approche plus complexe.

Dyspepsia is defined as epigastric pain that lasts at least one month and may be associated with a range of other upper gastrointestinal symptoms. Approximately 2/3 of outpatients with dyspepsia have a functional dyspepsia. The clinical assessment of dyspepsia is based on age of patients as well and the search for severity criteria. The endoscopy in cases of new-onset dyspepsia is recommended from an age of 55-60 and the presence of at least 1 severity criteria. A non-invasive test for Helicobacter pylori (HP) should be performed in all patients and followed by HP eradication when HP test is positive. The first-choice treatment of functional dyspepsia is a proton pump inhibitor (PPI) at maximal dose for 8 weeks. A therapeutic trial with a prokinetic or a central neuromodulator are alternatives to consider in case of failure of PPI treatment.

La dyspepsie est définie comme une douleur épigastrique qui dure au moins 1 mois et qui peut être associée à une gamme d'autres symptômes gastro-intestinaux supérieurs. Environ deux tiers des consultations ambulatoires pour dyspepsie sont d'origine fonctionnelle. L'évaluation clinique est basée sur l'âge du patient et la recherche de critère de gravité. Une endoscopie d'emblée en cas de dyspepsie nouvelle est indiquée dès 55 à 60 ans ou en présence de critères de gravité. Un test non invasif pour Helicobacter pylori (HP) est indiqué chez tous les patients en vue d'une éradication si le test HP est positif. Pour la dyspepsie fonctionnelle, un inhibiteur de la pompe à protons (IPP) durant 8 semaines est le traitement de choix. En cas d'échec, un essai thérapeutique avec un procinétique ou un neuromodulateur central sont des alternatives à considérer.

[New approaches to risk and the use of electronic tools in primary care medicine in 2021]. / Approches du risque et usage d'outils électroniques en médecine de premier recours en 2021.

Our selection of articles published in 2021 sheds light on topics related to risk, and to the use of electronic tools in primary care medicine. They cover blood pressure targets, telemonitoring, and the omega-3 fatty acid diet in the elderly and/or in patients with high cardiovascular risk. They present the role of primary care physicians in the management of patients with NAFLD, and in screening for domestic violence in all couples. They assess the risk of recurrence of a depressive episode after stopping antidepressant treatment. Finally, they discuss the place of apps to communicate with foreign-speaking patients and of vaping in smoking cessation.

Notre sélection d'articles parus en 2021 propose un éclairage sur des sujets en lien avec le risque chez nos patient·e·s et l'usage d'outils électroniques. Ils abordent le thème des cibles tensionnelles, du télémonitoring, et du régime riche en acides gras oméga 3 chez la personne âgée et/ou à haut risque cardiovasculaire. Ils présentent le rôle des médecins de premier recours dans la prise en charge de patient·e·s avec une stéatopathie métabolique, et dans le dépistage des violences conjugales dans tous les couples. Ils évaluent les risques de récidive d'épisode dépressif à l'arrêt d'un traitement antidépresseur. Enfin, ils discutent la place des applications pour la communication avec les patient·e·s allophones et du vapotage dans l'arrêt du tabac.

[Gynécology-obstretric - Perinatal smoking cessation support : why and how ?] / Gynécologie-obstétrique - Aide à l'arrêt du tabac en période périnatale : pourquoi et comment ?

In Switzerland, tobacco smoking is a major public health problem, especially among pregnant women. Health problems encountered by pregnant women and their fetuses require specific care to assist smoking cessation. A specific consultation to support smoking cessation during pregnancy was created in May 2019 at the maternity ward of the University Hospitals of Geneva, with the support of the Fondation Privée des Hôpitaux Universitaires de Genève and Carrefour addictionS/CIPRET-Genève. The creation of a network of health professionnals trained in smoking cessation is an important step to support women during their cessation process.

Le tabagisme en Suisse, et particulièrement chez la femme enceinte, est un problème majeur de santé publique. Les problèmes de santé que rencontrent les femmes enceintes et leurs fœtus nécessitent une prise en soins spécifique pour le soutien à l'abstinence tabagique. Une consultation spécifique d'aide au sevrage tabagique durant la grossesse a été créée en mai 2019 à la maternité des HUG, avec le soutien de la Fondation privée des HUG et de Carrefour addictionS/Centre d'information pour la prévention du tabagisme de Genève. La création d'un réseau d'aide par les professionnels formés en tabacologie de base constitue une étape importante pour soutenir les femmes durant le sevrage tabagique.

[Ambulatory shift in general internal medicine: a need for evidence beyond economical aspects]. / Virage ambulatoire en médecine interne générale: un besoin d'évidences au-delà de l'aspect économique.

General internal medicine is particularly concerned by the shift from stationary to ambulatory care, a shift that unfortunately is more often discussed from an economic perspective than from the angle of evidence. This article presents the results of studies and reviews published in 2019 that investigated the effectiveness of ambulatory instead of stationary care.

La médecine interne générale est particulièrement concernée par le virage ambulatoire, virage malheureusement plus souvent discuté sous l'angle économique que sous l'angle des évidences. Cet article présente les résultats d'études et de revues publiées en 2019 et ayant investigué l'efficacité de prises en charge ambulatoires en complément ou en remplacement de prises en charge stationnaires.

[Addictions]. / Addictions.

This article describes a new form of administration of inhaled prescribed heroin currently under investigation. It underlines the particularity of opioid agonist prescription in jail and presents new perspectives in using psilocybin in addiction medicine treatment. A brief literature review about vaping confirms its interest in quitting cigarette, with a cost of addiction to vaping and recent worrisome reports of chemical pneumonia. Finally, the withdrawal of WHO guidelines on opiates use in pain management, in the context of a suspicion of conflict of interest, underlines the sensible balance between over- and under- prescription of opiates in analgesic treatment.

Cet article montre l'intérêt d'une nouvelle forme d'administration inhalée d'héroïne pharmaceutique actuellement à l'étude. Il sensibilise aux conditions particulières de la prescription d'agonistes opioïdes en milieu carcéral et ressuscite des souvenirs des seventies en reprenant l'exploration scientifique des vertus thérapeutiques de la psilocybine. Même si le vapotage semble être un bon moyen de lâcher la cigarette, les anciens fumeurs ont tendance à s'y accrocher et un risque de pneumonie chimique parfois mortelle vient d'être mis en évidence. Finalement, le retrait de l'OMS de deux directives relatives à l'usage d'opioïdes dans le traitement de la douleur, sur fond de suspicion de conflit d'intérêts, montre l'équilibre délicat entre sur- et sous-prescription des antalgiques opioïdes.

Public smoking ban and socioeconomic inequalities in smoking prevalence and cessation: a cross-sectional population-based study in Geneva, Switzerland (1995-2014).

INTRODUCTION: Smoking bans were suggested to reduce smoking prevalence and increase quit ratio but their equity impact remains unclear. We aimed to characterise the socioeconomic status (SES)-related inequalities in smoking prevalence and quit ratio before and after the implementation of a public smoking ban. METHODS: We included data from 17 544 participants in the population-based cross-sectional Bus Santé study in Geneva, Switzerland, between 1995 and 2014. We considered educational attainment (primary, secondary and tertiary) as a SES indicator. Outcomes were smoking prevalence (proportion of current smokers) and quit ratio (ex-smokers to ever-smokers ratio). We used segmented linear regression to assess the overall impact of smoking ban on outcome trends. We calculated the relative (RII) and slope (SII, absolute difference) indexes of inequality, quantifying disparities between educational groups in outcomes overall (1995-2014), before and after ban implementation (November 2009). RESULTS: Least educated participants displayed higher smoking prevalence (RII=2.04, P<0.001; SII=0.15, P<0.001) and lower quit ratio (RII=0.73, P<0.001; SII=-0.18, P<0.001). As in other studies, smoking ban implementation coincided with a temporary reduction of smoking prevalence (P=0.003) and increase in quit ratio (P=0.02), with a progressive return to preban levels. Inequalities increased (P<0.05) in relative terms for smoking prevalence (RIIbefore=1.84, P<0.001 and RIIafter=3.01, P<0.001) and absolute terms for both outcomes (smoking prevalence: SIIbefore=0.14, P<0.001 and SIIafter=0.19, P<0.001; quit ratio: SIIbefore=-0.15, P<0.001 and SIIafter=-0.27, P<0.001). CONCLUSIONS: Implementation of a public smoking ban coincided with a short-lived decrease in smoking prevalence and increase in quit ratio but also with a widening in SES inequalities in smoking-related outcomes.

[Vaping (electronic cigarette): how to advise smokers in 2017 ?] / Vaporette (ou cigarette électronique) : quelles recommandations pour le fumeur en 2017 ?

Questions about electronic cigarettes, also called electronic nicotine delivery systems (ENDS), are very common when advising patients to stop smoking in medical practice. It is widely recognized that the risks of vaping are significantly lower than those of smoking, although there are uncertainties about its long-term health effects. Some studies suggest that vaping helps to stop smoking. Effective smoking cessation medications should be recommended in first line but vaping should not be discouraged when patients choose to use this device, as the main aim is smoking cessation. This paper proposes recommendations about vaping in common situations in medical practice with smokers.

Les questions concernant l'usage de la cigarette électronique, appelée aussi vaporette, sont très fréquentes lorsque le tabagisme est abordé en consultation médicale. Il est actuellement admis que les risques liés au vapotage sont nettement inférieurs à ceux du tabagisme, même si des incertitudes existent quant à ses effets sur la santé à long terme. Quelques études suggèrent que le vapotage aide à arrêter de fumer. Les médicaments d'aide à l'arrêt du tabac, dont l'efficacité est reconnue, sont à recommander en priorité mais le vapotage ne devrait pas être découragé chez les patients choisissant ce moyen, l'objectif étant de soutenir les fumeurs dans leur démarche d'arrêt du tabac. Cet article propose des recommandations concernant le vapotage pour les situations fréquentes en consultation médicale avec des fumeurs.

[Electronic cigarette: what do we know in 2015?]. / Cigarette eIectronique: le point en 2015.

Electronic cigarettes are devices producing vapour containing propylene-glycol, flavourings and quickly delivered nicotine. 6.7% of the Swiss population, mainly smokers, experimented the electronic cigarette while 0.1% use it daily. Despite uncertainty due to the low level of evidence, electronic cigarettes might be effective for smoking cessation and reduction. The safety of electronic cigarettes is demonstrated at short-term but not at long-term; however its eventual toxicity is likely to be much lower than tobacco. Use of electronic cigarettes by non-smokers and youth who do not smoke is low and seems unlikely to lead them to tobacco use. Recommended public health measures include product regulation with quality control, ban in public places, prohibition of advertising and sales to minors.

[Teaching practice recommendations: prevention and screening]. / Enseignement de recommandations pour la pratique: la prévention et le dépistage.

The aim of this article is to provide guidance to family doctors on how to tutor students about effective screening and primary prevention. Family doctors know their patients and adapt national and international guidelines to their specific context, risk profile, sex and age as well as to the prevalence of the disorders under consideration. Three cases are presented to illustrate guideline use according to the level of evidence (for a 19-year-old man, a 60-year-old woman, and an 80-year-old man). A particular strength of family medicine is that doctors see their patients over the years. Thus they can progressively go through the various prevention strategies, screening, counselling and immunisation, accompanying their patients with precious advice for their health throughout their lifetime.

Text-messaging versus telephone reminders to reduce missed appointments in an academic primary care clinic: a randomized controlled trial.

BACKGROUND: Telephone or text-message reminders have been shown to significantly reduce the rate of missed appointments in different medical settings. Since text-messaging is less resource-demanding, we tested the hypothesis that text-message reminders would be as effective as telephone reminders in an academic primary care clinic. METHODS: A randomized controlled non-inferiority trial was conducted in the academic primary care division of the Geneva University Hospitals between November 2010 and April 2011. Patients registered for an appointment at the clinic, and for whom a cell phone number was available, were randomly selected to receive a text-message or a telephone call reminder 24 hours before the planned appointment. Patients were included each time they had an appointment. The main outcome was the rate of unexplained missed appointments. Appointments were not missed if they were cancelled or re-scheduled before or independently from the intervention. We defined non-inferiority as a difference below 2% in the rate of missed appointments and powered the study accordingly. A satisfaction survey was conducted among a random sample of 900 patients (response rate 41%). RESULTS: 6450 patients were included, 3285 in the text-message group and 3165 in the telephone group. The rate of missed appointments was similar in the text-message group (11.7%, 95% CI: 10.6-12.8) and in the telephone group (10.2%, 95% CI: 9.2-11.3 p = 0.07). However, only text message reminders were cost-effective. No patient reported any disturbance by any type of reminder in the satisfaction survey. Three quarters of surveyed patients recommended its regular implementation in the clinic. CONCLUSIONS: Text-message reminders are equivalent to telephone reminders in reducing the proportion of missed appointments in an academic primary care clinic and are more cost-effective. Both types of reminders are well accepted by patients.

Implementation and impact of anti-smoking interventions in three prisons in the absence of appropriate legislation.

OBJECTIVE: To assess the acceptability and impact of anti-smoking policies in three prisons in Switzerland. METHODS: A before-after intervention study in A) an open prison for sentenced prisoners, B) a closed prison for sentenced prisoners, and C) a prison for pretrial detainees. Prisoners and staff were surveyed before (2009, n=417) and after (2010-2011, n=228) the interventions. Medical staff were trained to address tobacco dependence systematically in prisoners. In prison A, a partial smoking ban was extended. No additional protection against second-hand smoke was feasible in prisons B and C. RESULTS: In prison A, more prisoners reported receiving medical help to quit smoking in 2011 (20%) than in 2009 (4%, p=0.012). In prison A, prisoners and staff reported less exposure to second-hand smoke in 2011 than in 2009: 31% of prisoners were exposed to smoke at workplaces in 2009 vs 8% in 2011 (p=0.001); in common rooms: 43% vs 8%, (p<0.001). No changes were observed in prisons B and C. CONCLUSIONS: Reinforcement of non-smoking rules was possible in only one of the three prisons but had an impact on exposure to tobacco smoke and medical help to quit. Implementing anti-smoking policies in prisons is difficult in the absence of appropriate legislation.

The neighborhood environment and its association with the spatio-temporal footprint of tobacco consumption and changes in smoking-related behaviors in a Swiss urban area.

This study aimed to evaluate the association of the neighborhood environment with the spatio-temporal dependence of tobacco consumption and changes in smoking-related behaviors in a Swiss urban area. Data were obtained from the CoLaus cohort (2003-2006, 2009-2012, and 2014-2017) in Lausanne, Switzerland. Local Moran's I was performed to assess the spatial dependence of tobacco consumption. Prospective changes in tobacco consumption and the location of residence of participants were assessed through Cox regressions. Analyses were adjusted by individual and neighborhood data. The neighborhood environment was spatially associated with tobacco consumption and changes in smoking-related behaviors independently of individual factors.

Associations between urinary biomarkers of oxidative stress and biomarkers of tobacco smoke exposure in smokers.

Oxidative stress can contribute to the development of diseases, and may originate from exposures to toxicants commonly found in air pollution and cigarette smoke such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Yet, associations between these exposures and oxidative stress biomarkers are poorly characterized. We report here novel associations between 14 exposure biomarkers of PAHs and VOCs, and two oxidative stress biomarkers; 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) and 8-isoprostaglandin F2α (8-isoprostane) in urine obtained from smokers participating in an ongoing clinical study (ESTxENDS, NCT03589989). We also assessed associations between six biomarkers of tobacco smoke exposure (metabolites of nicotine and tobacco-specific nitrosamines (TSNAs)) and both oxidative stress biomarkers. We then quantified the relative importance of each family of the 20 exposure biomarkers on oxidative stress. Participating smokers (153 men and 117 women, median age 44 years) had on average smoked 25 [2-62] years and smoked about 17 [5-40] cigarettes per day at the time of the study. Multiple linear regression results showed an association between 8-oxodG concentrations and the following metabolites in decreasing relative importance: PAHs (beta coefficient ß = 0.105, p-value <0.001, partial R2 = 0.15) > VOCs (ß = 0.028, p < 0.001, partial R2 = 0.09) > nicotine (ß = 0.226, p < 0.001, partial R2 = 0.08); and between 8-isoprostane concentrations and metabolites of PAHs (ß = 0.117, p < 0.001, partial R2 = 0.14) > VOCs (ß = 0.040, p < 0.001, partial R2 = 0.14) > TSNAs (ß = 0.202, p = 0.003, partial R2 = 0.09) > nicotine (ß = 0.266, p < 0.001, partial R2 = 0.08). Behavioral factors known to contribute to oxidative stress, including sleep quality, physical activity, and alcohol consumption, did not play a significant role. Exposures to PAHs and VOCs among smokers were significantly associated with oxidative stress.

International expert consensus on electronic nicotine delivery systems and heated tobacco products: a Delphi survey.

OBJECTIVES: To provide a consensus from a panel of international experts about electronic nicotine delivery systems (ENDS) and heated tobacco products (HTP). DESIGN: Cross-sectional survey. METHODS: A Delphi survey was conducted among international experts in tobacco control and smoking cessation. The first part addressed statements or recommendations about ENDS, the second about HTP, both divided into four categories: regulation, sale, use and general issues. SETTING: Experts from 15 countries. PARTICIPANTS: Individuals with clinical, public health or research expertise in tobacco control and/or smoking cessation. RESULTS: 268 experts were contacted, 92 (34%) completed the first, 55/92 (60%) the second round. Consensus for ENDS: components of e-liquids, an upper limit of nicotine concentration should be defined; a warning on the lack of evidence in long-term safety and addiction potential should be stated; ENDS should not be regulated as consumer products but either as a new category of nicotine delivery or tobacco products; ENDS should not be sold in general stores but in specialised shops, shops selling tobacco or in pharmacies with restriction on sale to minors; administration of illegal drugs is likely with ENDS. Consensus for HTP: HTP have the same addictive potential as cigarettes; they should be regulated as a tobacco product with similar warning messages as cigarettes; their advertisement should not be allowed. ENDS and HTP use should not be allowed in indoor public places; a specific tax should be implemented for ENDS, taxes on HTP should not be lower than those for cigarettes; use of cigarettes is more likely with both ENDS and HTP (dual use) than quitting smoking. CONCLUSIONS: Experts in tobacco control and/or smoking cessation recommend differential regulation for ENDS and HTP. The results of this survey may be useful for health authorities, decision makers and researchers of the tobacco use and cessation field.

Spatial clusters of daily tobacco consumption before and after a smoke-free policy implementation.

This study assessed the spatial dependence of daily tobacco consumption and how it is spatially impacted by individual and neighborhood socioeconomic determinants, and tobacco consumption facilities before and after a smoke-free implementation. Individual data was obtained from the Bus Santé, a cross-sectional survey in Geneva. Spatial clusters of high and low tobacco consumption were assessed using Getis-Ord Gi*. Daily tobacco consumption was not randomly clustered in Geneva and may be impacted by tobacco consumption facilities independently of socioeconomic factors and a smoking ban. Spatial analysis should be considered to highlight the impact of smoke-free policies and guide public health interventions.

Association between self-reported motivation to quit smoking with effectiveness of smoking cessation intervention among patients hospitalized for acute coronary syndromes in Switzerland.

Guidelines recommend brief smoking cessation interventions for hospitalized smokers reporting low motivation-to-quit. However, an intensive smoking cessation intervention may improve smoking cessation for these smokers. We conducted a secondary analysis of a pre-post interventional study that tested the efficacy of a proactive approach systematically offering intensive smoking cessation intervention to all hospitalized smokers with acute coronary syndrome (ACS) compared to a reactive approach offering it only to smokers willing to quit. We analyzed data from one study site in Switzerland, which recorded motivation-to-quit smoking at study inclusion between 08.2009 and 02.2012. The primary outcome was smoking cessation at 1- and 5-year. We tested for interaction by participant's motivation-to-quit score (low vs. high motivation), and calculated multivariable adjusted risk ratios (RR), stratified by motivation score. We obtained motivation scores for 230 smokers. Follow-up was 94% (217/230) at 1-year and 68% (156/230) at 5-year. Among participants with low motivation to quit, 19% of smokers in the reactive phase had quit at 1 year compared to 50% of smokers in the proactive phase (multivariable adjusted RR = 2.85, 95%CI:0.91-8.91). Among highly motivated smokers, rates did not differ between phases: 48% vs. 49% (multivariable adjusted RR = 1.02, 95%CI:0.75-1.39, p-value for interaction between motivation-to-quit categories = 0.10). At 5-year follow-up, the point estimates were similar. While our study has limitations inherent to the study design and sample size, we found that a proactive approach to offer systematic smoking cessation counseling for smokers with ACS reporting low motivation to quit was associated with higher smoking cessation rates at 1 year.

Chickenpox in a Swiss prison: susceptibility, post-exposure vaccination and control measures.

After the occurrence of a case of chickenpox in Switzerland's largest pre-trial prison, protective measures including post-exposure vaccination were implemented, as chickenpox can cause severe complications in adults. Serology for chickenpox was carried out for all contacts of the index case and rapid post-exposure vaccination proposed to all prisoners with a negative history for chickenpox. Susceptibility was found in 14 out of 110 prisoners (12.7%; 95% confidence interval 6.5-18.9). The positive predictive value of a history of chickenpox was 90%. In this predominantly migrant population, susceptibility to chickenpox was approximately 6 times higher than in the general Swiss adult population. Since the attack rate among susceptible household contacts is usually high, preventive measures such as vaccination and quarantine probably allowed containment of the spread of infection.