Emily B. Kahn

Impact of azithromycin on oropharyngeal carriage of Group A streptococcus and nasopharyngeal carriage of macrolide-resistant streptococcus pneumoniae

BACKGROUND Invasive group A streptococcal (GAS) infections are a cause of serious morbidity and high mortality. There is a need for a simple, effective antimicrobial regimen that could be used to prevent invasive GAS disease in high risk situations. To assess azithromycin as a chemoprophylactic agent, we evaluated its efficacy for eradication of oropharyngeal (OP) GAS and its impact on the nasopharyngeal (NP) colonization rate of macrolide-resistant Streptococcus pneumoniae. METHODS We obtained OP and NP swabs for GAS and pneumococcus culture, respectively, from 300 schoolmates of a child with an invasive GAS infection. GAS culture-positive students were treated with daily azithromycin (12 mg/kg/day) for 5 days. We obtained follow-up OP and NP swabs at 9 (Day 17) and 24 (Day 32) days post-treatment from those students identified as GAS carriers on Day 0 and determined macrolide susceptibility of GAS and pneumococcal isolates. RESULTS Of the 300 students swabbed 152 (50%) carried GAS in their oropharynx. On Day 17, efficacy of azithromycin for GAS eradication was 95% (140 of 147) for all students. NP colonization rates for pneumococci decreased from 46% (67 of 146) to 12% (17 of 144; P < 0.001) by Day 17 and to 20% (27 of 137; P < 0.001) by Day 32. The prevalence of erythromycin-resistant pneumococcal isolates increased from 2% (3 of 146) to 4% (6 of 144) by Day 17 and to 8% (11 of 137; P = 0.04) by Day 32. CONCLUSIONS Azithromycin is an effective short course regimen for eradication of oropharyngeal GAS. However, azithromycin selected for macrolide-resistant strains of pneumococci. These findings highlight the importance of determining the appropriate circumstances for antimicrobial prophylaxis to prevent invasive GAS infections.

Attitudes and practices of obstetrician-gynecologists regarding influenza vaccination in pregnancy.

OBJECTIVE: To assess knowledge, attitudes, and practices of obstetrician–gynecologists (ob-gyns) regarding vaccination of pregnant women during the 2009 H1N1 pandemic. METHODS: From February to July 2010, a self-administered mail survey was conducted among a random sample of American College of Obstetricians and Gynecologists (the College) members involved in obstetric care. To assess predictors of routinely offering influenza vaccination, adjusted prevalence ratios and 95% confidence intervals (CIs) were calculated from survey data. RESULTS: Among 3,096 survey recipients, 1,310 (42.3%) responded to the survey, of whom 873 were eligible for participation. The majority of ob-gyns reported routinely offering both seasonal and 2009 H1N1 influenza vaccination to their pregnant patients (77.6% and 85.6%, respectively) during the 2009–2010 season; 21.1% and 13.3% referred patients to other specialists. Reported reasons for not offering vaccination included inadequate reimbursement, storage limitations, or belief that vaccine should be administered by another provider. Seasonal and 2009 H1N1 influenza vaccination during the first trimester was not recommended by 10.6% and 9.6% of ob-gyns, respectively. Predictors of routinely offering 2009 H1N1 influenza vaccine included: considering primary care and preventive medicine a very important part of practice (adjusted prevalence ratio 1.2, CI 1.01–1.4); observing serious conditions attributed to influenza-like illness (adjusted prevalence ratio 1.1, CI 1.02–1.1); personally receiving 2009 H1N1 influenza vaccination (adjusted prevalence ratio 1.2, CI 1.1–1.4); and practicing in multispecialty group (adjusted prevalence ratio 1.1, CI 1.1–1.2). Physicians in solo practice were less likely to routinely offer influenza vaccine (adjusted prevalence ratio 0.8, CI 0.7–0.9). CONCLUSION: Although most ob-gyns routinely offered influenza vaccination to pregnant patients, vaccination coverage rates may be improved by addressing logistic and financial challenges of vaccine providers. LEVEL OF EVIDENCE: III

Public response to the 2009 influenza A H1N1 pandemic: a polling study in five countries.

BACKGROUND Many important strategies to reduce the spread of pandemic influenza need public participation. To assess public receptivity to such strategies, we compared adoption of preventive behaviours in response to the 2009 H1N1 influenza pandemic among the public in five countries and examined whether certain non-pharmaceutical behaviours (such as handwashing) were deterrents to vaccination. We also assessed public support for related public health recommendations. METHODS We used data from simultaneous telephone polls (mobile telephone and landline) in Argentina, Japan, Mexico, the UK, and the USA. In each country, interviews were done in a nationally representative sample of adults, who were selected by the use of random digit dial techniques. The questionnaire asked people whether or not they had adopted each of various preventive behaviours (non-pharmaceutical--such as personal protective and social distancing behaviour--or vaccinations) to protect themselves or their family from H1N1 at any point during the pandemic. Two-tailed t tests were used for statistical analysis. FINDINGS 900 people were surveyed in each country except the USA where 911 people were contacted. There were wide differences in the adoption of preventive behaviours between countries, although certain personal protective behaviours (eg, handwashing) were more commonly adopted than social distancing behaviours (eg, avoiding places where many people gather) across countries (53-89%vs 11-69%). These non-pharmaceutical behaviours did not reduce the likelihood of getting vaccinated in any country. There was also support across all countries for government recommendations related to school closure, avoiding places where many people gather, and wearing masks in public. INTERPRETATION There is a need for country-specific approaches in pandemic policy planning that use both non-pharmaceutical approaches and vaccination. FUNDING US Centers for Disease Control and Prevention and the National Public Health Information Coalition.

Early Experience Conducting School-located Vaccination Programs for Seasonal Influenza

OBJECTIVES We determined program effectiveness, feasibility, and acceptance of school-located vaccination (SLV) clinics for seasonal influenza that took place before the 2008 universal influenza vaccination recommendations. METHODS We surveyed program directors of 23 programs in the United States who conducted SLV clinics during the 2005 to 2006 and 2006 to 2007 influenza seasons. RESULTS Of 391 423 children enrolled in schools with SLV clinics, 61 463 (15.7%) were vaccinated at 499 sites (schools) in 23 programs. Of these, 22 were small- and medium-sized programs that vaccinated 32 875 (24.1%) of the 136 151 children enrolled there, averaging 31.9% of students per site. One populous county vaccinated an additional 28 588 (11.2%) of its 255 272 enrolled children, averaging 13.9% per school. Children in grades K to 6 had consistently higher mean vaccination rates (21.5%) compared with middle school children (10.3%) or high school youth (5.8%). Program acceptability was high, and no program had to forego any key public health activities; 5 hired temporary help or paid overtime. The outlook for continuing such clinics was good in 7 programs, but depended on help with vaccine purchasing (9), funding (8), or additional personnel (4), with multiple responses allowed. CONCLUSIONS These vaccination coverage rates provide a baseline for future performance of school-located mass vaccination clinics. Although the existence and conduct of these programs in our study was considered acceptable by leaders of public health departments and anecdotally by parents and school administrators, sustainability may require additional means to pay for vaccines or personnel beyond the usual available health department resources.

Adoption of preventive behaviors in response to the 2009 H1N1 influenza pandemic: a multiethnic perspective

As public health leaders prepare for possible future influenza pandemics, the rapid spread of 2009 H1N1 influenza highlights the need to focus on measures the public can adopt to help slow disease transmission. Such measures may relate to hygiene (e.g., hand washing), social distancing (e.g., avoiding places where many people gather), and pharmaceutical interventions (e.g., vaccination). Given the disproportionate impact of public health emergencies on minority communities in the United States, it is important to understand whether there are differences in acceptance across racial/ethnic groups that could lead to targeted and more effective policies and communications.

Use of nonpharmaceutical interventions to reduce transmission of 2009 pandemic influenza A (pH1N1) in Pennsylvania public schools.

BACKGROUND School-based recommendations for nonpharmaceutical interventions (NPIs) were issued in response to the threat of 2009 pandemic influenza A (pH1N1). The implementation and effectiveness of these recommendations has not been assessed. METHODS In November 2009, a Web-based survey of all Pennsylvania public schools was conducted to assess the use of recommended NPIs. RESULTS Overall, 1040 (31%) of 3351 schools participated in the survey. By fall 2009, 820 (84%) of 979 respondents reported that their school had an influenza plan in place, a 44% higher proportion than in the spring 2009 (p < .01). Most schools communicated health messages (eg, staying home when sick), implemented return to school requirements, and made hand sanitizer available. Schools with a spring influenza plan (N = 568) were less likely to report substantial influenza-like illness (ILI) during the fall wave of influenza than the 299 schools without a spring influenza plan (63% vs 71%, p = .02). This association persisted after controlling for schools with substantial ILI in the spring. CONCLUSION The reported use of NPIs in participating Pennsylvania public schools improved substantially from spring to fall and was generally consistent with issued recommendations. The proactive implementation of a number of NPIs and the early implementation of communication and education initiatives might have cumulatively reduced the impact of pH1N1 in some schools.

Modeling in Real Time During the Ebola Response

To aid decision-making during CDCs response to the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC activated a Modeling Task Force to generate estimates on various topics related to the response in West Africa and the risk for importation of cases into the United States. Analysis of eight Ebola response modeling projects conducted during August 2014-July 2015 provided insight into the types of questions addressed by modeling, the impact of the estimates generated, and the difficulties encountered during the modeling. This time frame was selected to cover the three phases of the West African epidemic curve. Questions posed to the Modeling Task Force changed as the epidemic progressed. Initially, the task force was asked to estimate the number of cases that might occur if no interventions were implemented compared with cases that might occur if interventions were implemented; however, at the peak of the epidemic, the focus shifted to estimating resource needs for Ebola treatment units. Then, as the epidemic decelerated, requests for modeling changed to generating estimates of the potential number of sexually transmitted Ebola cases. Modeling to provide information for decision-making during the CDC Ebola response involved limited data, a short turnaround time, and difficulty communicating the modeling process, including assumptions and interpretation of results. Despite these challenges, modeling yielded estimates and projections that public health officials used to make key decisions regarding response strategy and resources required. The impact of modeling during the Ebola response demonstrates the usefulness of modeling in future responses, particularly in the early stages and when data are scarce. Future modeling can be enhanced by planning ahead for data needs and data sharing, and by open communication among modelers, scientists, and others to ensure that modeling and its limitations are more clearly understood. The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

Cost-effectiveness of dog rabies vaccination programs in East Africa

Background Dog rabies annually causes 24,000–70,000 deaths globally. We built a spreadsheet tool, RabiesEcon, to aid public health officials to estimate the cost-effectiveness of dog rabies vaccination programs in East Africa. Methods RabiesEcon uses a mathematical model of dog-dog and dog-human rabies transmission to estimate dog rabies cases averted, the cost per human rabies death averted and cost per year of life gained (YLG) due to dog vaccination programs (US 2015 dollars). We used an East African human population of 1 million (approximately 2/3 living in urban setting, 1/3 rural). We considered, using data from the literature, three vaccination options; no vaccination, annual vaccination of 50% of dogs and 20% of dogs vaccinated semi-annually. We assessed 2 transmission scenarios: low (1.2 dogs infected per infectious dog) and high (1.7 dogs infected). We also examined the impact of annually vaccinating 70% of all dogs (World Health Organization recommendation for dog rabies elimination). Results Without dog vaccination, over 10 years there would a total of be approximately 44,000–65,000 rabid dogs and 2,100–2,900 human deaths. Annually vaccinating 50% of dogs results in 10-year reductions of 97% and 75% in rabid dogs (low and high transmissions scenarios, respectively), approximately 2,000–1,600 human deaths averted, and an undiscounted cost-effectiveness of

Practices of obstetrician-gynecologists regarding nonvaccine-related public health recommendations during the 2009 H1N1 influenza pandemic

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Antiviral treatment for outpatient use during an influenza pandemic: a decision tree model of outcomes averted and cost-effectiveness

385 per life saved. Semi-annual vaccination of 20% of dogs results in in 10-year reductions of 94% and 78% in rabid dogs, and approximately 2,000–1,900 human deaths averted, and cost