In October 2011, in an effort to reduce the burden of pertussis in infants, the Advisory Committee on Immunization Practices (ACIP) recommended that unvaccinated pregnant women receive a dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap). Vaccination of women with Tdap during pregnancy is expected to provide some protection to infants from pertussis until they are old enough to be vaccinated themselves. Tdap given to pregnant women will stimulate the development of maternal antipertussis antibodies, which will pass through the placenta, likely providing the newborn with protection against pertussis in early life, and will protect the mother from pertussis around the time of delivery, making her less likely to become infected and transmit pertussis to her infant. The 2011 Tdap recommendation did not call for vaccinating pregnant women previously vaccinated with Tdap. On October 24, 2012, ACIP voted to recommend use of Tdap during every pregnancy. This report summarizes data considered and conclusions made by ACIP and provides guidance for implementing its recommendations. These updated recommendations on use of Tdap in pregnant women aim to optimize strategies for preventing pertussis morbidity and mortality in infants.

Meningococcal disease describes the spectrum of infections caused by Neisseria meningiditis, including meningitdis, bacteremia, and bacteremic pneumonia. Two quadrivalent meningococcal polysaccharide-protein conjugate vaccines that provide protection against meningococcal serogroups A, C, W, and Y (MenACWY-D [Menactra, manufactured by Sanofi Pasteur, Inc., Swiftwater, Pennsylvania] and MenACWY-CRM [Menveo, manufactured by Novartis Vaccines, Cambridge, Massachusetts]) are licensed in the United States for use among persons aged 2 through 55 years. MenACWY-D also is licensed for use among infants and toddlers aged 9 through 23 months. Quadrivalent meningococcal polysaccharide vaccine (MPSV4 [Menommune, manufactured by sanofi pasteur, Inc., Swiftwater, Pennsylvania]) is the only vaccine licensed for use among persons aged ≥56 years. A bivalent meningococcal polysaccharide protein conjugate vaccine that provides protection against meningococcal serogroups C and Y along with Haemophilus influenzae type b (Hib) (Hib-MenCY-TT [MenHibrix, manufactured by GlaxoSmithKline Biologicals, Rixensart, Belgium]) is licensed for use in children aged 6 weeks through 18 months. This report compiles and summarizes all recommendations from CDC's Advisory Committee on Immunization Practices (ACIP) regarding prevention and control of meningococcal disease in the United States, specifically the changes in the recommendations published since 2005 (CDC. Prevention and control of meningococcal disease: recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 2005;54 [No. RR-7]). As a comprehensive summary of previously published recommendations, this report does not contain any new recommendations; it is intended for use by clinicians as a resource. ACIP recommends routine vaccination with a quadrivalent meningococcal conjugate vaccine (MenACWY) for adolescents aged 11 or 12 years, with a booster dose at age 16 years. ACIP also recommends routine vaccination for persons at increased risk for meningococcal disease (i.e., persons who have persistent complement component deficiencies, persons who have anatomic or functional asplenia, microbiologists who routinely are exposed to isolates of N. meningitidis, military recruits, and persons who travel to or reside in areas in which meningococcal disease is hyperendemic or epidemic). Guidelines for antimicrobial chemoprophylaxis and for evaluation and management of suspected outbreaks of meningococcal disease also are provided.

At its October 2012 meeting, the Advisory Committee on Immunization Practices (ACIP) voted to recommend vaccination against meningococcal serogroups C and Y for children aged 6 weeks through 18 months at increased risk for meningococcal disease. Meningococcal groups C and Y and Haemophilus b tetanus toxoid conjugate vaccine (Hib-MenCY-TT [MenHibrix, GlaxoSmithKline Biologicals]) is licensed for active immunization for prevention of invasive disease caused by Haemophilus influenzae type b (Hib) and meningococcal serogroups C and Y. Hib-MenCY-TT is not indicated for prevention of disease caused by meningococcal serogroup B, the most common serogroup causing disease in infants, or serogroups W135 or A, which are represented in quadrivalent meningococcal vaccines. Before licensure of Hib-MenCY-TT, no meningococcal conjugate vaccine was licensed for infants aged 2 through 8 months. MenACWY-D (Menactra, Sanofi Pasteur) is licensed as a 2-dose series for infants and toddlers aged 9 through 23 months, and MenACWY-D and MenACWY-CRM (Menveo, Novartis Vaccines) are licensed for persons aged 2 through 55 years as a single dose. These vaccines are recommended routinely for persons aged 11 through 18 years and persons aged 2 through 55 years at increased risk for meningococcal disease (and persons aged 9 months through 55 years for MenACWY-D). This report summarizes the deliberations of ACIP, the rationale for its decision, and recommendations for use of Hib-MenCY-TT in infants at increased risk for meningococcal disease.

These recommendations from the Advisory Committee on Immunization Practices (ACIP) update the previous recommendations for anthrax vaccine adsorbed (AVA) (CDC. Use of anthrax vaccine in the United States: Recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 2000;49:1-20; CDC. Use of anthrax vaccine in response to terrorism: supplemental recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 2002;51:1024-6) and reflect the status of anthrax vaccine supplies in the United States. This statement 1) provides updated information on anthrax epidemiology; 2) summarizes the evidence regarding the effectiveness and efficacy, immunogenicity, and safety of AVA; 3) provides recommendations for pre-event and preexposure use of AVA; and 4) provides recommendations for postexposure use of AVA. In certain instances, recommendations that did not change were clarified. No new licensed anthrax vaccines are presented. Substantial changes to these recommendations include the following: 1) reducing the number of doses required to complete the pre-event and preexposure primary series from 6 doses to 5 doses, 2) recommending intramuscular rather than subcutaneous AVA administration for preexposure use, 3) recommending AVA as a component of postexposure prophylaxis in pregnant women exposed to aerosolized Bacillus anthracis spores, 4) providing guidance regarding preexposure vaccination of emergency and other responder organizations under the direction of an occupational health program, and 5) recommending 60 days of antimicrobial prophylaxis in conjunction with 3 doses of AVA for optimal protection of previously unvaccinated persons after exposure to aerosolized B. anthracis spores.

This article summarizes what is currently known about the 2019 novel coronavirus and offers interim guidance.

In December 2020, two COVID-19 vaccines (Pfizer-BioNTech and Moderna) were authorized for emergency use in the United States for the prevention of coronavirus disease 2019 (COVID-19).* Because of limited initial vaccine supply, the Advisory Committee on Immunization Practices (ACIP) prioritized vaccination of health care personnel(†) and residents and staff members of long-term care facilities (LTCF) during the first phase of the U.S. COVID-19 vaccination program (1). Both vaccines require 2 doses to complete the series. Data on vaccines administered during December 14, 2020-January 14, 2021, and reported to CDC by January 26, 2021, were analyzed to describe demographic characteristics, including sex, age, and race/ethnicity, of persons who received ≥1 dose of COVID-19 vaccine (i.e., initiated vaccination). During this period, 12,928,749 persons in the United States in 64 jurisdictions and five federal entities(§) initiated COVID-19 vaccination. Data on sex were reported for 97.0%, age for 99.9%, and race/ethnicity for 51.9% of vaccine recipients. Among persons who received the first vaccine dose and had reported demographic data, 63.0% were women, 55.0% were aged ≥50 years, and 60.4% were non-Hispanic White (White). More complete reporting of race and ethnicity data at the provider and jurisdictional levels is critical to ensure rapid detection of and response to potential disparities in COVID-19 vaccination. As the U.S. COVID-19 vaccination program expands, public health officials should ensure that vaccine is administered efficiently and equitably within each successive vaccination priority category, especially among those at highest risk for infection and severe adverse health outcomes, many of whom are non-Hispanic Black (Black), non-Hispanic American Indian/Alaska Native (AI/AN), and Hispanic persons (2,3).

In the United States and around the world, measles (a serious, potentially fatal, and extremely contagious infection) was considered a disease of the past until recently. However, what was once old news is now making headlines again with a remarkably predictable storyline: when immunity to measles falls in a population, outbreaks soon follow. This scenario has unfolded in places such as Ukraine, the Philippines, Israel, and Samoa with devastating consequences.1 In 2019 alone, the United Kingdom and 3 other European countries lost measles elimination status in part because of vaccine hesitancy, or the delay in acceptance or the refusal of vaccination despite availability of vaccination services, which was named one of the top global public health threats by the World Health Organization. Amid this global measles resurgence, the United States experienced a chain reaction of measles cases imported into close-knit, undervaccinated communities (primarily by unvaccinated US residents carrying measles home from outbreaks abroad), leading to outbreaks across the country in 2018 and 2019. These outbreaks were fueled by targeted vaccine misinformation and resulted in the highest number of measles cases in almost 30 years, nearly costing the United States its measles elimination status.2 To protect our nation, we need to change this narrative. We must empower families, in all communities and across generations, to feel confident in the decision to vaccinate.

Objectives: Evaluate different non-continuous temperature-monitoring practices for detection of out-of-range temperatures (above or below the recommended temperature range of 2-8 degreeC for refrigeration units), which are called excursions, within vaccine storage units. Method(s): Simulations based on temperature data collected by 243 digital data loggers operated in vaccine storage units at health-care providers who participated in a CDC-sponsored continuous temperature monitoring pilot project, from 2012 to 2015. In the primary analysis, we evaluate: (1) twice-daily current temperature readings without minimum and maximum readings (min/max), (2) twice-daily current temperature readings with once-daily min/max, and (3) twice-daily current temperature readings with twice-daily min/max. Result(s): Recording current temperature twice daily without min/max resulted in the detection of 4.8-6.4% of the total number of temperature excursions. When min/max readings were introduced, the percentage of detected temperature excursions increased to 27.8-96.6% with once-daily min/max and to 34.8-96.7% with twice-daily min/max. Conclusion(s): Including min/max readings improves the ability of a temperature monitoring practice to detect temperature excursions. No combination of the non-continuous temperature monitoring practices were able to consistently detect all simulated temperature excursions.

This study aims to evaluate the cost-benefit of vaccination services, mostly partial series administration, provided by a mobile clinic program (MCP) in Houston for children of transient and low-income families. The study included 469 patients who visited the mobile clinics on regular service days in 2 study periods in 2014 and 836 patients who attended vaccination events in the summer of 2014. The benefit of partial series vaccination was estimated based on vaccine efficacy/effectiveness data. Our conservative cost-benefit estimates show that, compared with office-based settings, every dollar spent on vaccination by the MCP would result in $0.9 societal cost averted as an incremental benefit in regular service days and $3.7 during vaccination-only events. To further improve the cost-benefit of vaccination services in the MCP, decision-makers and stakeholders may consider improving work efficiency during regular service days or hosting more vaccination events.

This report updates the 2009 recommendations from the CDC Advisory Committee on Immunization Practices (ACIP) regarding use of anthrax vaccine in the United States (Wright JG, Quinn CP, Shadomy S, Messonnier N. Use of anthrax vaccine in the United States: recommendations of the Advisory Committee on Immunization Practices [ACIP)], 2009. MMWR Recomm Rep 2010;59[No. RR-6]). The report 1) summarizes data on estimated efficacy in humans using a correlates of protection model and safety data published since the last ACIP review, 2) provides updated guidance for use of anthrax vaccine adsorbed (AVA) for preexposure prophylaxis (PrEP) and in conjunction with antimicrobials for postexposure prophylaxis (PEP), 3) provides updated guidance regarding PrEP vaccination of emergency and other responders, 4) summarizes the available data on an investigational anthrax vaccine (AV7909), and 5) discusses the use of anthrax antitoxins for PEP. Changes from previous guidance in this report include the following: 1) a booster dose of AVA for PrEP can be given every 3 years instead of annually to persons not at high risk for exposure to Bacillus anthracis who have previously received the initial AVA 3-dose priming and 2-dose booster series and want to maintain protection; 2) during a large-scale emergency response, AVA for PEP can be administered using an intramuscular route if the subcutaneous route of administration poses significant materiel, personnel, or clinical challenges that might delay or preclude vaccination; 3) recommendations on dose-sparing AVA PEP regimens if the anthrax vaccine supply is insufficient to vaccinate all potentially exposed persons; and 4) clarification on the duration of antimicrobial therapy when used in conjunction with vaccine for PEP.These updated recommendations can be used by health care providers and guide emergency preparedness officials and planners who are developing plans to provide anthrax vaccine, including preparations for a wide-area aerosol release of B. anthracis spores. The recommendations also provide guidance on dose-sparing options, if needed, to extend the supply of vaccine to increase the number of persons receiving PEP in a mass casualty event.

Epidemic meningitis has posed a recurrent threat for more than a century for the approximately 430 million people living in the 26 countries in the sub-Saharan region of Africa known as the “meningitis belt.” This population experiences high rates of endemic meningitis, annual seasonal outbreaks, and explosive epidemics occurring every 5–12 years. Hope to eliminate this devastating public health threat came in the form of a novel meningococcal serogroup A conjugate vaccine (MACV [MenAfriVac]) developed by the Meningitis Vaccine Project (MVP; available at: http://www.meningvax.org) specifically for use in the meningitis belt and priced at less than $1.00 per dose [1]. Licensed in 2009, MACV was subsequently prequalified by the World Health Organization (WHO) on the basis of its safety and immunogenicity data but without phase 3 efficacy studies. Starting in 2010, MACV was rolled out across the meningitis belt via mass campaigns to vaccinate all persons 1–29 years of age. By the end of 2018, >300 million people in 22 African countries had been immunized with MACV [2]. The vaccine has been a remarkable public health success, effectively eliminating serogroup A meningitis epidemics in sub-Saharan Africa [3].

BACKGROUND: Adult and adolescent vaccination rates are far below coverage targets in the United States. Our objective was to identify the most influential factors related to vaccine uptake among adults, adolescents, and parents of adolescents (parents) in the United States. METHODS: We used a fractional factorial design to create a binary choice survey to evaluate preferences for vaccination. The national survey was fielded to a sample of adults, adolescents ages 13-17 years, and parents, using a national probability-based online research panel in November 2015. Respondents were presented with 5 profiles of a hypothetical vaccine and asked in a series of questions whether they would accept each vaccine. We analyzed the binary choice data using logistic regression in STATA v13 (College Station, TX) to calculate the odds that a participant would choose to accept the vaccine. RESULTS: We received completed responses from 334 (51%) of 652 adults, 316 (21%) of 1516 adolescents, and 339 (33%) of 1030 parents. Respondents were generally representative of the U.S. POPULATION: Vaccine effectiveness was the most influential factor in the choice to vaccinate for all groups. Other most influential factors were primary care provider (PCP) recommendation and the out-of-pocket cost of the vaccine. Other factors such as risk of illness, risk of vaccine side effects, vaccination location, and time for vaccination were not important in the decision to get vaccinated. CONCLUSIONS: Adults, adolescents, and parents are most sensitive to vaccine effectiveness, PCP recommendation, and out-of-pocket cost for vaccination in their decision to get vaccinated. Strong PCP recommendations that focus on vaccine effectiveness and health care policies that minimize out-of-pocket costs for vaccinations may increase vaccine uptake by adults and adolescents.

PURPOSE: Measure the preferences of decision makers and researchers associated with the Advisory Committee on Immunization Practices (ACIP) regarding the recommended format for presenting health economics studies to the ACIP. METHODS: We conducted key informant interviews and an online survey of current ACIP work group members, and current and previous ACIP voting members, liaison representatives, and ex-officio members to understand preferences for health economics presentations. These preferences included the presentation of results and sensitivity analyses, the role of health economics studies in decision making, and strategies to improve guidelines for presenting health economics studies. Best-worst scaling was used to measure the relative value of seven attributes of health economics presentations in vaccine decision making. RESULTS: The best-worst scaling survey had a response rate of 51% (n=93). Results showed that summary results were the most important attribute for decision making (mean importance score: 0.69) and intermediate outcomes and disaggregated results were least important (mean importance score: -0.71). Respondents without previous health economics experience assigned sensitivity analysis lower importance and relationship of the results to other studies higher importance than the experienced group (sensitivity analysis scores: -0.15 vs. 0.15 respectively; relationship of the results: 0.13 vs. -0.12 respectively). Key informant interviews identified areas for improvement to include additional information on the quality of the analysis and increased role for liaisons familiar with health economics. CONCLUSION: Additional specificity in health economics presentations could allow for more effective presentations of evidence for vaccine decision making.

The need for closer linkages between scientific and programmatic areas focused on addressing vaccine-preventable and acute respiratory infections led to establishment of the National Center for Immunization and Respiratory Diseases (NCIRD) at the Centers for Disease Control and Prevention. During its first 10 years (2006-2015), NCIRD worked with partners to improve preparedness and response to pandemic influenza and other emergent respiratory infections, provide an evidence base for addition of 7 newly recommended vaccines, and modernize vaccine distribution. Clinical tools were developed for improved conversations with parents, which helped sustain childhood immunization as a social norm. Coverage increased for vaccines to protect adolescents against pertussis, meningococcal meningitis, and human papillomavirus-associated cancers. NCIRD programs supported outbreak response for new respiratory pathogens and oversaw response of the Centers for Disease Control and Prevention to the 2009 influenza A(H1N1) pandemic. Other national public health institutes might also find closer linkages between epidemiology, laboratory, and immunization programs useful.

This report compiles and summarizes all recommendations from CDC's Advisory Committee on Immunization Practices (ACIP) regarding prevention and control of tetanus, diphtheria, and pertussis in the United States. As a comprehensive summary of previously published recommendations, this report does not contain any new recommendations and replaces all previously published reports and policy notes; it is intended for use by clinicians and public health providers as a resource. ACIP recommends routine vaccination for tetanus, diphtheria, and pertussis. Infants and young children are recommended to receive a 5-dose series of diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccines, with one adolescent booster dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine. Adults who have never received Tdap also are recommended to receive a booster dose of Tdap. Women are recommended to receive a dose of Tdap during each pregnancy, which should be administered from 27 through 36 weeks' gestation, regardless of previous receipt of Tdap. After receipt of Tdap, adolescents and adults are recommended to receive a booster tetanus and diphtheria toxoids (Td) vaccine every 10 years to assure ongoing protection against tetanus and diphtheria.

OBJECTIVE: To estimate the societal economic and health impacts of Maine's school-based influenza vaccination (SIV) program during the 2009 A(H1N1) influenza pandemic. DATA SOURCES: Primary and secondary data covering the 2008-09 and 2009-10 influenza seasons. STUDY DESIGN: We estimated weekly monovalent influenza vaccine uptake in Maine and 15 other states, using difference-in-difference-in-differences analysis to assess the program's impact on immunization among six age groups. We also developed a health and economic Markov microsimulation model and conducted Monte Carlo sensitivity analysis. DATA COLLECTION: We used national survey data to estimate the impact of the SIV program on vaccine coverage. We used primary data and published studies to develop the microsimulation model. PRINCIPAL FINDINGS: The program was associated with higher immunization among children and lower immunization among adults aged 18-49 years and 65 and older. The program prevented 4,600 influenza infections and generated $4.9 million in net economic benefits. Cost savings from lower adult vaccination accounted for 54 percent of the economic gain. Economic benefits were positive in 98 percent of Monte Carlo simulations. CONCLUSIONS: SIV may be a cost-beneficial approach to increase immunization during pandemics, but programs should be designed to prevent lower immunization among nontargeted groups.

Vaccine purchase cost has grown substantially over the last few decades. A closer look at vaccine prices reveals that not all vaccines shared the same increasing pattern. Various factors, such as vaccine attributes, competition, and supply shortages, could relate to price changes. In this study, we examined whether a variety of factors influenced the prices of noninfluenza childhood vaccines purchased in the public sector from 1996 to 2014. The association differed among price-capped vaccines and combination vaccines. There was an increasing time trend in real prices for non-price-capped vaccines, which was mostly offset by the effect of market longevity. The effect of competition in lowering prices was more pronounced among non-price-capped vaccines when manufacturer and vaccine component fixed effects were excluded. Supply shortage, manufacturer name change, and number of vaccine doses in series showed no effect. The results may help policy makers better understand price behaviors and make more informed decisions in vaccine planning and financing.

BACKGROUND: Meningococcal conjugate vaccines were licensed beginning in 2005 on the basis of serologic end points and recommended for use in adolescents. A single dose at age 11 to 12 years was expected to provide protection through late adolescence. We conducted a case-control evaluation of vaccine effectiveness (VE) and duration of protection of a meningococcal (groups A, C, W, and Y) polysaccharide diphtheria toxoid conjugate vaccine (MenACWY-D). METHODS: Cases of culture- or polymerase chain reaction-confirmed serogroup A, C, W, and Y meningococcal disease among adolescents were identified through meningococcal disease surveillance sites in the United States from January 1, 2006, through August 31, 2013. Attempts were made to enroll 4 friend and school controls per case. VE was calculated using the generalized estimating equation, controlling for underlying medical conditions and smoking. RESULTS: Serogroup C accounted for 88 (49%), serogroup Y 80 (44%), and serogroup W 13 (7%) of enrolled cases. Thirty-six (20%) cases and 87 (44%) controls received MenACWY-D. The overall VE estimate 0 to 8 years postvaccination was 69% (51% to 80%); VE was 79% (49% to 91%) at <1 year, 69% (44% to 83%) at 1 to <3 years, and 61% (25% to 79%) at 3 to <8 years. VE was 77% (57% to 88%) against serogroup C and 51% (1% to 76%) against serogroup Y. CONCLUSIONS: MenACWY-D was effective in the first year after vaccination but effectiveness waned 3 to <8 years postvaccination. The estimates of VE from this evaluation informed the Advisory Committee on Immunization Practices in its decision to add a booster dose of MenACWY.

While vaccination remains as one of the most cost-effective preventive strategies, the cost of fully immunizing a child has grown considerably over the last few decades. This study examines trends in non-influenza childhood vaccine purchase costs in the public sector from 1996 to 2014. Non-influenza vaccine purchase cost per child for children aged 0 through 18years was calculated based on public-sector purchase prices. Purchase cost changes were then decomposed into changes attributable to recommendation updates and changes attributable to price variation. The study analyzed the growth rate of combination vaccine prices separately and compared these prices with the sum of prices of component vaccines. It is found that the average annual growth rate of non-influenza vaccine purchase cost per child during 1996-2014 was 12.6%. The growth rate attributable to price changes was 1.0% on average. Combination vaccine prices showed greater variation. The study concludes that vaccine price variation was one but a minor reason for purchase cost changes. Recommendation updates, particularly the introduction of new vaccines, played a much larger role in raising the purchase costs. If the 12.6% annual growth rate found during 1996-2014 in the study continues to apply, the purchase costs of childhood vaccines may more than double by 2020.

OBJECTIVE: To determine the optimal level of vaccination coverage defined as the level that minimizes total costs and explore how economic results change with marginal changes to this level of coverage. METHODS: A susceptible-infected-recovered-vaccinated model designed to represent theoretical infectious diseases was created to simulate disease spread. Parameter inputs were defined to include ranges that could represent a variety of possible vaccine-preventable conditions. Costs included vaccine costs and disease costs. Health benefits were quantified as monetized quality adjusted life years lost from disease. Primary outcomes were the number of infected people and the total costs of vaccination. Optimization methods were used to determine population vaccination coverage that achieved a minimum cost given disease and vaccine characteristics. Sensitivity analyses explored the effects of changes in reproductive rates, costs and vaccine efficacies on primary outcomes. Further analysis examined the additional cost incurred if the optimal coverage levels were not achieved. RESULTS: Results indicate that the relationship between vaccine and disease cost is the main driver of the optimal vaccination level. Under a wide range of assumptions, vaccination beyond the optimal level is less expensive compared to vaccination below the optimal level. This observation did not hold when the cost of the vaccine cost becomes approximately equal to the cost of disease. DISCUSSION AND CONCLUSION: These results suggest that vaccination below the optimal level of coverage is more costly than vaccinating beyond the optimal level. This work helps provide information for assessing the impact of changes in vaccination coverage at a societal level.

Immunological responses to vaccination can differ depending on whether the vaccine is given alone or with other vaccines. This study was a retrospective evaluation of the immunogenicity of a tetravalent meningococcal conjugate vaccine (MenACWY) administered alone (n = 41) or concomitantly with other vaccines (n = 279) to United States military personnel (mean age = 21.6 years) entering the military between 2006 and 2008. Concomitant vaccines included tetanus/diphtheria (Td), inactivated polio vaccine (IPV), hepatitis vaccines, various influenza vaccines, among others; two vaccine groups excluded Tdap and IPV. Immune responses were evaluated in baseline and post-vaccination sera for Neisseria meningitidis serogroups C and Y 1-12 months (mean = 4.96) following vaccination. Functional antibodies were measured by using a serum bactericidal antibody assay with rabbit complement (rSBA) and by measurement of serogroup-specific immunoglobulin G (IgG) antibodies. The percentage of vaccinees reaching threshold levels (IgG ≥2 mug/mL; rSBA titer ≥8) corresponding to an immunologic response was higher post-vaccination than at baseline (p < 0.001). Administration of MenACWY along with other vaccines was associated with higher geometric means of IgG concentrations and rSBA titers than those measured 4.60 months after a single dose of MenACWY. In addition, higher percentages of vaccinees reached the immunological threshold (odds ratios [ORs] range = 1.5 to 21.7) and more of them seroconverted (ORs range = 1.8 to 4.8) when MenACWY was administered with any other vaccine than when administered alone. Additional prospective randomized clinical trials are needed to confirm the observed differences among groups in the immune response to MenACWY when given concomitantly with other vaccines to United States military personnel.

OBJECTIVE: To evaluate the cost-effectiveness of seasonal inactivated influenza vaccination among pregnant women using data from three recent influenza seasons in the United States. DESIGN, SETTING, AND PARTICIPANTS: We developed a decision-analytic model following a cohort of 5.2 million pregnant women and their infants aged <6 months to evaluate the cost-effectiveness of vaccinating women against seasonal influenza during pregnancy from a societal perspective. The main outcome measures were quality-adjusted life-year (QALY) gained and cost-effectiveness ratios. Data sources included surveillance data, epidemiological studies, and published vaccine cost data. Sensitivity analyses were also performed. All costs and outcomes were discounted at 3% annually. MAIN OUTCOME MEASURES: Total costs (direct and indirect), effects (QALY gains, averted case numbers), and incremental cost-effectiveness of seasonal inactivated influenza vaccination among pregnant women (cost per QALY gained). RESULTS: Using a recent benchmark of 52.2% vaccination coverage among pregnant women, we studied a hypothetical cohort of 2,753,015 vaccinated pregnant women. With an estimated vaccine effectiveness of 73% among pregnant women and 63% among infants <6 months, QALY gains for each season were 305 (2010-2011), 123 (2011-2012), and 610 (2012-2013). Compared with no vaccination, seasonal influenza vaccination during pregnancy was cost-saving when using data from the 2010-2011 and 2012-2013 influenza seasons. The cost-effectiveness ratio was greater than $100,000/QALY with the 2011-2012 influenza season data, when CDC reported a low attack rate compared to other recent seasons. CONCLUSIONS: Influenza vaccination for pregnant women can reduce morbidity from influenza in both pregnant women and their infants aged <6 months. Seasonal influenza vaccination during pregnancy is cost-saving during moderate to severe influenza seasons.

INTRODUCTION: The United States experienced a substantial increase in reported pertussis cases over the last decade. Since 2005, persons 11 years and older have been routinely recommended to receive a single dose of tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine. The objective of this analysis was to evaluate the potential impact and cost-effectiveness of recommending a second dose of Tdap. METHODS: A static cohort model was used to calculate the epidemiologic and economic impact of adding a second dose of Tdap at age 16 or 21 years. Projected costs and outcomes were examined from a societal perspective over a 20-year period. Quality-adjusted Life Years (QALY) saved were calculated. RESULTS: Using baseline pertussis incidence from the National Notifiable Diseases Surveillance System, Tdap revaccination at either age 16 or 21 years would reduce outpatient visits by 433 (5%) and 285 (4%), and hospitalization cases by 7 (7%) and 5 (5%), respectively. The costs per QALY saved with a second dose of Tdap were approximately US $19.7 million (16 years) and $26.2 million (21 years). In sensitivity analyses, incidence most influenced the model; as incidence increased, the costs per QALY decreased. To a lesser degree, initial vaccine effectiveness and waning of effectiveness also affected cost outcomes. Multivariate sensitivity analyses showed that under a set of optimistic assumptions, the cost per QALY saved would be approximately $163,361 (16 years) and $204,556 (21 years). CONCLUSION: A second dose of Tdap resulted in a slight decrease in the number of cases and other outcomes, and that trend is more apparent when revaccinating at age 16 years than at age 21 years. Both revaccination strategies had high dollar per QALY saved even under optimistic assumptions in a multivariate sensitivity analysis.

BACKGROUND: During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010-2011 and its rollout from 2011 to 2013, >150 million eligible people, representing 12 hyperendemic meningitis countries, have been vaccinated. METHODS: The new vaccine effectiveness evaluation framework was established by the World Health Organization and partners. Meningitis case-based surveillance was strengthened in PsA-TT first-introducer countries, and several evaluation studies were conducted to estimate the vaccination coverage and to measure the impact of vaccine introduction on meningococcal carriage and disease incidence. RESULTS: PsA-TT implementation achieved high vaccination coverage, and results from studies conducted showed significant decrease of disease incidence as well as significant reduction of oropharyngeal carriage of group A meningococci in vaccinated and unvaccinated individuals, demonstrating the vaccine's ability to generate herd protection and prevent group A epidemics. CONCLUSIONS: Lessons learned from this experience provide useful insights in how to guide and better prepare for future new vaccine introductions in resource-limited settings.

BACKGROUND: Antimicrobial treatment and chemoprophylaxis of patients and their close contacts is critical to reduce the morbidity and mortality and prevent secondary cases of meningococcal disease. Through the 1990's, the prevalence of antimicrobial resistance to commonly used antimicrobials among Neisseria meningitidis was low in the United States. Susceptibility testing was performed to ascertain whether the proportions of isolates with reduced susceptibility to antimicrobials commonly used for N meningitidis have increased since 2004 in the United States. METHODS: Antimicrobial susceptibility testing was performed by broth microdilution on 466 isolates of N meningitidis collected in 2004, 2008, 2010, and 2011 from an active, population-based surveillance system for susceptibility to ceftriaxone, ciprofloxacin, penicillin G, rifampin, and azithromycin. The molecular mechanism of reduced susceptibility was investigated for isolates with intermediate or resistant phenotypes. RESULTS: All isolates were susceptible to ceftriaxone and azithromycin, 10.3% were penicillin G intermediate (range, 8% in 2008-16.7% in 2010), and <1% were ciprofloxacin, rifampin, or penicillin G resistant. Of the penicillin G intermediate or resistant isolates, 63% contained mutations in the penA gene associated with reduced susceptibility to penicillin G. All ciprofloxacin-resistant isolates contained mutations in the gyrA gene associated with reduced susceptibility. CONCLUSIONS:. Resistance of N meningitidis to antimicrobials used for empirical treatment of meningitis in the United States has not been detected, and resistance to penicillin G and chemoprophylaxis agents remains uncommon. Therapeutic agent recommendations remain valid. Although periodic surveillance is warranted to monitor trends in susceptibility, routine clinical testing may be of little use.

BACKGROUND: Acellular pertussis vaccines replaced whole-cell vaccines for the 5-dose childhood vaccination series in 1997. A sixth dose of pertussis-containing vaccine, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis, adsorbed (Tdap), was recommended in 2005 for adolescents and adults. Studies examining Tdap vaccine effectiveness (VE) among adolescents who have received all acellular vaccines are limited. METHODS: To assess Tdap VE and duration of protection, we conducted a matched case-control study during the 2012 pertussis epidemic in Washington among adolescents born during 1993-2000. All pertussis cases reported from January 1 through June 30, 2012, in 7 counties were included; 3 controls were matched by primary provider clinic and birth year to each case. Vaccination histories were obtained through medical records, the state immunization registry, and parent interviews. Participants were classified by type of pertussis vaccine received on the basis of birth year: a mix of whole-cell and acellular vaccines (1993-1997) or all acellular vaccines (1998-2000). We used conditional logistic regression to calculate odds ratios comparing Tdap receipt between cases and controls. RESULTS: Among adolescents who received all acellular vaccines (450 cases, 1246 controls), overall Tdap VE was 63.9% (95% confidence interval [CI]: 50% to 74%). VE within 1 year of vaccination was 73% (95% CI: 60% to 82%). At 2 to 4 years postvaccination, VE declined to 34% (95% CI: -0.03% to 58%). CONCLUSIONS: Tdap protection wanes within 2 to 4 years. Lack of long-term protection after vaccination is likely contributing to increases in pertussis among adolescents.

BACKGROUND: A new serogroup A meningococcal conjugate vaccine (PsA-TT, MenAfriVac) has been developed to combat devastating serogroup A Neisseria meningitis (MenA) epidemics in Africa. A mass immunization campaign targeting 1-29 year olds was conducted in Burkina Faso in December 2010. Protection of subsequent infant cohorts will be necessary through either introduction of PsA-TT into the routine Expanded Programme on Immunization (EPI) or periodic repeat mass vaccination campaigns. OBJECTIVES: To inform future immunization policy for PsA-TT vaccination of infants through a comparison of PsA-TT campaign vaccination coverage and routine measles-containing vaccine (MCV) coverage in Burkina Faso. METHODS: A national survey was conducted in Burkina Faso during December 17-27, 2011 using stratified cluster sampling to assess PsA-TT vaccine coverage achieved by the 2010 nationwide immunization campaign among 2-30 year olds and routine MCV coverage among 12-23 month olds. Coverage estimates and 95% Confidence Intervals (CI) were calculated, reasons for non-vaccination and methods of campaign communication were described, and a multivariable analysis for factors associated with vaccination was conducted. RESULTS: National overall PsA-TT campaign coverage was 95.9% (95% CI: 95.0-96.7) with coverage greater than 90% all 13 regions of Burkina Faso. National overall routine MCV coverage was 92.5% (95% CI: 90.5-94.1), but ranged from 75.3% to 95.3% by region. The primary predictor for PsA-TT vaccination among all age groups was a head of household informed of the campaign. PsA-TT vaccination was more likely in residents of rural settings, whereas MCV vaccination was more likely in residents of urban settings. CONCLUSION: Overall national vaccination rates in Burkina Faso were similar for PsA-TT and MCV vaccine. The regions with MCV coverage below targets may be at risk for sub-optimal vaccination coverage if PsA-TT is introduced in EPI. These results highlight the need for assessments of routine vaccination coverage to guide PsA-TT immunization policy in meningitis belt countries.

BACKGROUND: Meningococcal conjugate vaccines (MenACWY) against serogroups A, C, W and Y are recommended for routine use in adolescents aged 11-18 years. Impact of these vaccines on meningococcal population structure in the US remained to be evaluated. METHODS: Meningococcal isolates from 2006-10 (post-MenACWY) collected through Active Bacterial Core surveillance (ABCs) were characterized; serogroup distribution and molecular features of these isolates were compared to previously published data on ABCs isolates from 2000-05 (pre-MenACWY). p values were generated using chi-squared statistics and exact methods. RESULTS: There was a significant change (p<0.05) in serogroup distribution among all age groups between the two periods. A small proportion of isolates has shown evidence of capsular switching in both periods. Between the two periods, significant changes were observed in the distribution of PorA, FetA, and strain genotypes among vaccine and non-vaccine serogroups. CONCLUSIONS: The population structure of U.S. meningococcal isolates is dynamic; some changes occurred over time but the basic structure remained. Vaccine-induced serogroup replacement was not observed, although a small proportion of isolates had undergone capsule switching possibly driven by non-vaccine mediated selection. Changes in the distribution of molecular features are likely due to horizontal gene transfer and changes in serogroup distribution.

BACKGROUND: Meningococcal disease incidence in the U.S. is at an all-time low. In a previous study of Georgia high school students, meningococcal carriage prevalence was 7%. The purpose of this study was to measure the impact of a meningococcal conjugate vaccine on serogroup Y meningococcal carriage and to define the dynamics of carriage in high school students. METHODS: This was a prospective cohort study at 8 high schools, 4 each in Maryland and Georgia during a school year. In each state, 2 high schools were randomized for participating students to receive MCV4-DT at the beginning of the study and 2 at the end. Oropharyngeal swab cultures for meningococcal carriage were performed three times during the school year. RESULTS: Among 3,311 students, prevalence of meningococcal carriage was 3.21%- 4.01%. Phenotypically non-groupable strains accounted for 88% of carriage isolates. There were only 5 observed acquisitions of serogroup Y strains during the study; therefore, the impact of MCV4-DT on meningococcal carriage could not be determined. CONCLUSIONS: Meningococcal carriage rates in U.S. high school students were lower than expected and the vast majority of strains did not express capsule. These findings may help explain the historically low incidence of meningococcal disease in the U.S.

Serogroup C meningococcal (MenC) disease accounts for one-third of all meningococcal cases and causes meningococcal outbreaks in the U.S. Quadrivalent meningococcal vaccine conjugated to diphtheria toxoid (MenACYWD) was recommended in 2005 for adolescents and high risk groups such as military recruits. We evaluated anti-MenC antibody persistence in U.S. military personnel vaccinated with either MenACYWD or meningococcal polysaccharide vaccine (MPSV4). Twelve hundred subjects vaccinated with MenACYWD from 2006 to 2008 or MPSV4 from 2002 to 2004 were randomly selected from the Defense Medical Surveillance System. Baseline serologic responses to MenC were assessed in all subjects; 100 subjects per vaccine group were tested during one of the following six post-vaccination time-points: 5-7, 11-13, 17-19, 23-25, 29-31, or 35-37 months. Anti-MenC geometric mean titers (GMT) were measured by rabbit complement serum bactericidal assay (rSBA) and geometric mean concentrations (GMC) by enzyme-linked immunosorbent assay (ELISA). Continuous variables were compared using the Wilcoxon rank sum test and the proportion of subjects with an rSBA titer ≥8 by chi-square. Pre-vaccination rSBA GMT was <8 for the MenACWYD group. rSBA GMT increased to 703 at 5-7 months post-vaccination and decreased by 94% to 43 at 3 years post-vaccination. GMT was significantly lower in the MenACWYD group at 5-7 months post-vaccination compared to the MPSV4 group. The percentage of MenACWYD recipients achieving an rSBA titer of ≥8 decreased from 87% at 5-7 months to 54% at 3 years. There were no significant differences between vaccine groups in the proportion of subjects with a titer of ≥8 at any time-point. GMC for the MenACWYD group was 0.14mug/mL at baseline, 1.07mug/mL at 5-7 months, and 0.66mug/mL at 3 years, and significantly lower than the MPSV4 group at all time-points. Anti-MenC responses wane following vaccination with MenACYWD; a booster dose is needed to maintain protective levels of circulating antibody.