World Pneumonia Day 2011-2016: Twitter contents and retweets.

BACKGROUND: Twitter is used for World Pneumonia Day (WPD; November 12) communication. We evaluate if themes of #pneumonia tweets were associated with retweet frequency. METHODS: A total of 28 181 original #pneumonia tweets were retrieved (21 November 2016), from which six subcorpora, 1 mo before and 1 mo after WPD 2011-2016, were extracted (n=6721). Underlying topics were identified via latent Dirichlet allocation and were manually coded into themes. The association of themes with retweet count was assessed via multivariable hurdle regression. RESULTS: Compared with personal experience tweets, tweets that both raised awareness and promoted intervention were 2.62 times as likely to be retweeted (adjusted odds ratio [aOR] 2.62 [95% 1.79 to 3.85]) and if retweeted had 37% more retweets (adjusted prevalence ratio [aPR] 1.37 [95% CI 1.06 to 1.78]). Tweets that raised concerns about vaccine price were twice as likely to be retweeted (aOR 2.29 [95% CI 1.36 to 3.84]) and if retweeted, had double the retweet count (aPR 2.05 [95% CI 1.27 to 3.29]) of tweets sharing personal experience. CONCLUSIONS: The #pneumonia tweets that both raised awareness and promoted interventions and those discussing vaccine price were more likely to engage users than tweets about personal experience. These results help health professionals craft WPD messages that will engage the audience.

Cost-effectiveness of next-generation vaccines: The case of pertussis.

Despite steady vaccination coverage rates, pertussis incidence in the United States has continued to rise. This public health challenge has motivated calls for the development of a new vaccine with greater efficacy and duration of protection. Any next-generation vaccine would likely come at a higher cost, and must provide sufficient health benefits beyond those provided by the current vaccine in order to be deemed cost-effective. Using an age-structured transmission model of pertussis, we quantified the health and economic benefits of a next-generation vaccine that would enhance either the efficacy or duration of protection of the childhood series, the duration of the adult booster, or a combination. We developed a metric, the maximum cost-effective price increase (MCPI), to compare the potential value of such improvements. The MCPI estimates the per-dose price increase that would maintain the cost-effectiveness of pertussis vaccination. We evaluated the MCPI across a range of potential single and combined improvements to the pertussis vaccine. As an upper bound, we found that a next-generation vaccine which could achieve perfect efficacy for the childhood series would permit an MCPI of $18 per dose (95% CI: $12-$31). Pertussis vaccine improvements that extend the duration of protection to an average of 75 years would allow for an MCPI of $22 per dose for the childhood series (CI: $10-$33) or $12 for the adult booster (CI: $4-$18). Despite the short duration of the adult booster, improvements to the childhood series could be more valuable than improvements to the adult booster. Combining improvements in both efficacy and duration, a childhood series with perfect efficacy and average duration of 75 years would permit an MCPI of $39 per dose, the highest of any scenario evaluated. Our results highlight the utility of the MCPI metric in evaluating potential vaccines or other interventions when prices are unknown.

Epidemiological and Economic Effects of Priming With the Whole-Cell Bordetella pertussis Vaccine.

IMPORTANCE: Current acellular pertussis vaccines may not protect against transmission of Bordetella pertussis. OBJECTIVE: To assess whether a priming dose of whole-cell pertussis (wP) vaccine is cost-effective at reducing pertussis infection in infants. DESIGN, SETTING, AND PARTICIPANTS: Mathematical model of pertussis transmission fit to US incidence data in a simulation of the US population. In this simulation study conducted from June 2014 to May 2015, the population was divided into 9 age groups corresponding to the current pertussis vaccination schedule and fit to 2012 pertussis incidence. INTERVENTIONS: Inclusion of a priming dose of wP vaccine into the current acellular pertussis vaccination schedule. MAIN OUTCOMES AND MEASURES: Reductions in symptomatic pertussis incidence by age group, increases in wP vaccine-related adverse effects, and quality-adjusted life-years owing to changing vaccine schedule. RESULTS: Switching to a wP-priming vaccination strategy could reduce whooping cough incidence by up to 95% (95% CI, 91-98), including 96% (95% CI, 92-98) fewer infections in neonates. Although there may be an increase in the number of vaccine adverse effects, we nonetheless estimate a 95% reduction in quality-adjusted life-years lost with a switch to the combined strategy and a cost reduction of 94% (95% CI, 91-97), saving more than $142 million annually. CONCLUSIONS AND RELEVANCE: Our results suggest that an alternative vaccination schedule including 1 dose of wP vaccine may be highly cost-effective and ethically preferred until next-generation pertussis vaccines become available.

Revisiting the Rise of Electronic Nicotine Delivery Systems Using Search Query Surveillance.

INTRODUCTION: Public perceptions of electronic nicotine delivery systems (ENDS) remain poorly understood because surveys are too costly to regularly implement and, when implemented, there are long delays between data collection and dissemination. Search query surveillance has bridged some of these gaps. Herein, ENDS' popularity in the U.S. is reassessed using Google searches. METHODS: ENDS searches originating in the U.S. from January 2009 through January 2015 were disaggregated by terms focused on e-cigarette (e.g., e-cig) versus vaping (e.g., vapers); their geolocation (e.g., state); the aggregate tobacco control measures corresponding to their geolocation (e.g., clean indoor air laws); and by terms that indicated the searcher's potential interest (e.g., buy e-cigs likely indicates shopping)-all analyzed in 2015. RESULTS: ENDS searches are rapidly increasing in the U.S., with 8,498,000 searches during 2014 alone. Increasingly, searches are shifting from e-cigarette- to vaping-focused terms, especially in coastal states and states where anti-smoking norms are stronger. For example, nationally, e-cigarette searches declined 9% (95% CI=1%, 16%) during 2014 compared with 2013, whereas vaping searches increased 136% (95% CI=97%, 186%), even surpassing e-cigarette searches. Additionally, the percentage of ENDS searches related to shopping (e.g., vape shop) nearly doubled in 2014, whereas searches related to health concerns (e.g., vaping risks) or cessation (e.g., quit smoking with e-cigs) were rare and declined in 2014. CONCLUSIONS: ENDS popularity is rapidly growing and evolving. These findings could inform survey questionnaire development for follow-up investigation and immediately guide policy debates about how the public perceives the health risks or cessation benefits of ENDS.

US consumer interest in non-cigarette tobacco products spikes around the 2009 federal tobacco tax increase.

OBJECTIVES: This quasi-experimental longitudinal study monitored aggregate Google search queries as a proxy for consumer interest in non-cigarette tobacco products (NTP) around the time of the 2009 US federal tobacco tax increase. METHODS: Query trends for searches mentioning common NTP were downloaded from Google's public archives. The mean relative increase was estimated by comparing the observed with expected query volume for the 16 weeks around the tax. RESULTS: After the tax was announced, queries spiked for chewing tobacco, cigarillos, electronic cigarettes ('e-cigarettes'), roll-your-own (RYO) tobacco, snuff, and snus. E-cigarette queries were 75% (95% CI 70% to 80%) higher than expected 8 weeks before and after the tax, followed by RYO 59% (95% CI 53% to 65%), snus 34% (95% CI 31% to 37%), chewing tobacco 17% (95% CI 15% to 20%), cigarillos 14% (95% CI 11% to 17%), and snuff 13% (95% CI 10% to 14%). Unique queries increasing the most were 'ryo cigarettes' 427% (95% CI 308% to 534%), 'ryo tobacco' 348% (95% CI 300% to 391%), 'best electronic cigarette' 221% (95% CI 185% to 257%), and 'e-cigarette' 205% (95% CI 163% to 245%). CONCLUSIONS: The 2009 tobacco tax increase triggered large increases in consumer interest for some NTP, particularly e-cigarettes and RYO tobacco.

Population health concerns during the United States' Great Recession.

BACKGROUND: Associations between economic conditions and health are usually derived from cost-intensive surveys that are intermittently collected with nonspecific measures (i.e., self-rated health). PURPOSE: This study identified how precise health concerns changed during the U.S. Great Recession analyzing Google search queries to identify the concern by the query content and their prevalence by the query volume. METHODS: Excess health concerns were estimated during the Great Recession (December 2008 through 2011) by comparing the cumulative difference between observed and expected (based on linear projections from pre-existing trends) query volume for hundreds of individual terms. As performed in 2013, the 100 queries with the greatest excess were ranked and then clustered into themes based on query content. RESULTS: The specific queries with the greatest relative excess were stomach ulcer symptoms and headache symptoms, respectively, 228% (95% CI=35, 363) and 193% (95% CI=60, 275) greater than expected. Queries typically involved symptomology (i.e., gas symptoms) and diagnostics (i.e., heart monitor) naturally coalescing into themes. Among top themes, headache queries were 41% (95% CI=3, 148); hernia 37% (95% CI=16, 142); chest pain 35% (95% CI=6, 313); and arrhythmia 32% (95% CI=3, 149) greater than expected. Pain was common with back, gastric, joint, and tooth foci, with the latter 19% (95% CI=4, 46) higher. Among just the top 100, there were roughly 205 million excess health concern queries during the Great Recession. CONCLUSIONS: Google queries indicate that the Great Recession coincided with substantial increases in health concerns, hinting at how population health specifically changed during that time.

Digital detection for tobacco control: online reactions to the 2009 U.S. cigarette excise tax increase.

INTRODUCTION: The Internet is revolutionizing tobacco control, but few have harnessed the Web for surveillance. We demonstrate for the first time an approach for analyzing aggregate Internet search queries that captures precise changes in population considerations about tobacco. METHODS: We compared tobacco-related Google queries originating in the United States during the week of the State Children's Health Insurance Program (SCHIP) 2009 cigarette excise tax increase with a historic baseline. Specific queries were then ranked according to their relative increases while also considering approximations of changes in absolute search volume. RESULTS: Individual queries with the largest relative increases the week of the SCHIP tax were "cigarettes Indian reservations" 640% (95% CI, 472-918), "free cigarettes online" 557% (95% CI, 432-756), and "Indian reservations cigarettes" 542% (95% CI, 414-733), amounting to about 7,500 excess searches. By themes, the largest relative increases were tribal cigarettes 246% (95% CI, 228-265), "free" cigarettes 215% (95% CI, 191-242), and cigarette stores 176% (95% CI, 160-193), accounting for 21,000, 27,000, and 90,000 excess queries. All avoidance queries, including those aforementioned themes, relatively increased 150% (95% CI, 144-155) or 550,000 from their baseline. All cessation queries increased 46% (95% CI, 44-48), or 175,000, around SCHIP; including themes for "cold turkey" 19% (95% CI, 11-27) or 2,600, cessation products 47% (95% CI, 44-50) or 78,000, and dubious cessation approaches (e.g., hypnosis) 40% (95% CI, 33-47) or 2,300. CONCLUSIONS: The SCHIP tax motivated specific changes in population considerations. Our strategy can support evaluations that temporally link tobacco control measures with instantaneous population reactions, as well as serve as a springboard for traditional studies, for example, including survey questionnaire design.

Novel surveillance of psychological distress during the great recession.

BACKGROUND: Economic stressors have been retrospectively associated with net population increases in nonspecific psychological distress (PD). However, no sentinels exist to evaluate contemporaneous associations. Aggregate Internet search query surveillance was used to monitor population changes in PD around the United States' Great Recession. METHODS: Monthly PD query trends were compared with unemployment, underemployment, homes in delinquency and foreclosure, median home value or sale prices, and S&P 500 trends for 2004-2010. Time series analyses, where economic indicators predicted PD one to seven months into the future, were performed in 2011. RESULT: PD queries surpassed 1,000,000 per month, of which 300,000 may be attributable to the Great Recession. A one percentage point increase in mortgage delinquencies and foreclosures was associated with a 16% (95%CI, 9-24) increase in PD queries one-month, and 11% (95%CI, 3-18) four months later, in reference to a pre-Great Recession mean. Unemployment and underemployment had similar associations half and one-quarter the intensity. "Anxiety disorder", "what is depression", "signs of depression", "depression symptoms", and "symptoms of depression" were the queries exhibiting the strongest associations with mortgage delinquencies and foreclosures, unemployment or underemployment. Housing prices and S&P 500 trends were not associated with PD queries. LIMITATIONS: A non-traditional measure of PD was used. It is unclear if actual clinically significant depression or anxiety increased during the Great Recession. Alternative explanations for strong associations between the Great Recession and PD queries, such as media, were explored and rejected. CONCLUSIONS: Because the economy is constantly changing, this work not only provides a snapshot of recent associations between the economy and PD queries but also a framework and toolkit for real-time surveillance going forward. Health resources, clinician screening patterns, and policy debate may be informed by changes in PD query trends.

A novel evaluation of World No Tobacco day in Latin America.

BACKGROUND: World No Tobacco Day (WNTD), commemorated annually on May 31, aims to inform the public about tobacco harms. Because tobacco control surveillance is usually annualized, the effectiveness of WNTD remains unexplored into its 25th year. OBJECTIVE: To explore the potential of digital surveillance (infoveillance) to evaluate the impacts of WNTD on population awareness of and interest in cessation. METHODS: Health-related news stories and Internet search queries were aggregated to form a continuous and real-time data stream. We monitored daily news coverage of and Internet search queries for cessation in seven Latin American nations from 2006 to 2011. RESULTS: Cessation news coverage peaked around WNTD, typically increasing 71% (95% confidence interval [CI] 61-81), ranging from 61% in Mexico to 83% in Venezuela. Queries indicative of cessation interest peaked on WNTD, increasing 40% (95% CI 32-48), ranging from 24% in Colombia to 84% in Venezuela. A doubling in cessation news coverage was associated with approximately a 50% increase in cessation queries. To gain a practical perspective, we compared WNTD-related activity with New Year's Day and several cigarette excise tax increases in Mexico. Cessation queries around WNTD were typically greater than New Year's Day and approximated a 2.8% (95% CI -0.8 to 6.3) increase in cigarette excise taxes. CONCLUSIONS: This novel evaluation suggests WNTD had a significant impact on popular awareness (media trends) and individual interest (query trends) in smoking cessation. Because WNTD is constantly evolving, our work is also a model for real-time surveillance and potential improvement in WNTD and similar initiatives.

Evolution in health and medicine Sackler colloquium: a public choice framework for controlling transmissible and evolving diseases.

Control measures used to limit the spread of infectious disease often generate externalities. Vaccination for transmissible diseases can reduce the incidence of disease even among the unvaccinated, whereas antimicrobial chemotherapy can lead to the evolution of antimicrobial resistance and thereby limit its own effectiveness over time. We integrate the economic theory of public choice with mathematical models of infectious disease to provide a quantitative framework for making allocation decisions in the presence of these externalities. To illustrate, we present a series of examples: vaccination for tetanus, vaccination for measles, antibiotic treatment of otitis media, and antiviral treatment of pandemic influenza.