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1.  Active Surveillance for Adverse Events After a Mass Vaccination Campaign With a Group A Meningococcal Conjugate Vaccine (PsA-TT) in Mali 
Background. The monovalent meningococcal A conjugate vaccine (PsA-TT, MenAfriVac) was developed for use in the “meningitis belt” of sub-Saharan Africa. Mali was 1 of 3 countries selected for early introduction. As this is a new vaccine, postlicensure surveillance is particularly important to identify and characterize possible safety issues.
Methods. The national vaccination campaign was phased from September 2010 to November 2011. We conducted postlicensure safety surveillance for PsA-TT in 40 government clinics from southern Mali serving approximately 400 000 people 1–29 years of age. We conducted analyses with individual-level data and population-level data, and we calculated rates of adverse events using the conditional exact test, a modified vaccine cohort risk interval method, and a modified self-controlled case series method for each outcome of interest, including 18 prespecified adverse events and 18 syndromic categories.
Results. An increased rate of clinic visits for fever within 3 days after vaccination was found using multiple methods for all age groups. Although other signals were found with some methods, complete assessment of all other prespecified outcomes and syndromic categories did not reveal that PsA-TT was consistently associated with any other health problem.
Conclusions. No new safety concerns were identified in this study. These results are consistent with prelicensure data and other studies indicating that PsA-TT is safe. The approach presented could serve as a model for future active postlicensure vaccine safety monitoring associated with large-scale immunization campaigns in low-income countries.
PMCID: PMC4639483  PMID: 26553680
vaccine safety; PsA-TT; MenAfriVac; meningitis belt; meningococcal vaccine
2.  Physicians’ Human Papillomavirus Vaccine Recommendations, 2009 and 2011 
Physician recommendation is a key predictor of human papillomavirus (HPV) vaccine uptake. Understanding factors associated with recommendation is important for efforts to increase current suboptimal vaccine uptake.
This study aimed to examine physician recommendations to vaccinate female patients aged 11–26 years, in 2009 and 2011, at 3 and 5 years postvaccine licensure, respectively. A second aim was to identify trends in factors associated with vaccine recommendation for ages 11 and 12 years.
Nationally representative samples of physicians practicing family medicine, pediatrics, and obstetrics and gynecology were randomly selected from the American Medical Association Physician Masterfile (n=1538 in 2009, n=1541 in 2011). A mailed survey asked physicians about patient and clinical practice characteristics; immunization support; and frequency of HPV vaccine recommendation (“always” = >75% of the time vs other). Analyses were conducted in 2012.
Completed surveys were received from 1013 eligible physicians (68% response rate) in 2009 and 928 (63%) in 2011. The proportion of physicians who reported “always” recommending HPV vaccine increased significantly from 2009 to 2011 for patients aged 11 or 12 years (35% vs 40%, respectively; p=0.03), but not for patients aged 13–17 years (53% vs 55%; p= 0.28) or 18–26 years (50% vs 52%; p=0.52). Physician specialty, age, and perceived issues/barriers to vaccination were associated with vaccine recommendation for patients aged 11 or 12 in both years.
Results suggest a modest increase in recommendations for HPV vaccination of girls aged 11 or 12 years over a 2-year period; however, recommendations remain suboptimal for all age groups despite national recommendations for universal immunization.
PMCID: PMC3895928  PMID: 24355675
3.  Immune response to 1 and 2 dose regimens of Measles vaccine in Pakistani children 
Human Vaccines & Immunotherapeutics  2013;9(12):2529-2532.
Measles is a significant problem in Pakistan despite vaccine coverage rates reported at 80%. The purpose of this study was to determine the serologic response in children after one dose of measles vaccine at 9 mo versus two doses at 9 and 15 mo of age. From March through December 2006, children were enrolled from immunization clinics and squatter settlements in Karachi. Blood samples were taken from children in Group A at 9–10 mo of age prior to measles vaccine and 8 to 11 weeks later; from children in Group B at 16–17 mo of age after receiving 2 doses of measles vaccine; and from children in Group C who had received at least one dose of measles vaccine by 5 y of age. After the first dose of measles vaccine, 107/147 (73%) of children in Group A were seropositive, 157/180 (87%) of children in Group B were seropositive after two doses and 126/200 (63%) of children in Group C were seropositive at 5 y of age. The post-vaccination geometric mean antibody concentrations were higher in females than males in groups A (irrespective of pre-vaccination antibody levels) and B. The serologic response to one and two doses of measles vaccine was lower in children in Karachi than has been reported in many other countries. Two doses of vaccine were significantly better than one dose. An in-depth investigation is needed to determine the reason for the lower-than-expected protection rates. Differences in immunogenicity between genders need to be further studied. Recent introduction of supplemental measles vaccine doses should help control measles in Pakistan.
PMCID: PMC4162044  PMID: 23928952
Measles vaccine; measles vaccine effectiveness; serologic response; Pakistan and Geometric mean titers
4.  Understanding STI Risk and Condom Use Patterns by Partner Type Among Female Sex Workers in Peru 
The Open AIDS Journal  2014;8:17-20.
While brothel-based sex work is regulated by the Peruvian government, there is little data on STI risk factors reported by female sex workers (FSW). This study compared high risk behaviors among 120 Peruvian FSW from government regulated brothels with both clients and non-commercial partners. Our study found that 12% of FSW reported unprotected vaginal sex with clients (compared to 75% with non-commercial partners), and 42% reported unprotected anal sex with clients (compared to 87% with non-commercial partners). Group differences were observed in the expectation to have oral sex (32% for partners vs 60% for clients; p<0.01), and a history of anal sex (65% for partners vs 32% for clients; p<0.01) and both vaginal and anal sex with the same partners (46% for partners vs 25% for clients; p<0.001). These findings suggest that FSW constitute an important bridge population for STI/HIV transmission in Peru.
PMCID: PMC4062928  PMID: 24949112
Bridge population; condom use patterns; female sex workers; Peru; STI risk and transmission.
5.  Are Recent Medical Graduates More Skeptical of Vaccines? 
Vaccines  2013;1(2):154-166.
Rates of delay and refusal of recommended childhood vaccines are increasing in many U.S. communities. Children’s health care providers have a strong influence on parents’ knowledge, attitudes, and beliefs about vaccines. Provider attitudes towards immunizations vary and affect their immunization advocacy. One factor that may contribute to this variability is their familiarity with vaccine-preventable diseases and their sequelae. The purpose of this study was to investigate the association of health care provider year of graduation with vaccines and vaccine-preventable disease beliefs. We conducted a cross sectional survey in 2005 of primary care providers identified by parents of children whose children were fully vaccinated or exempt from one or more school immunization requirements. We examined the association of provider graduation cohort (5 years) with beliefs on immunization, disease susceptibility, disease severity, vaccine safety, and vaccine efficacy. Surveys were completed by 551 providers (84.3% response rate). More recent health care provider graduates had 15% decreased odds of believing vaccines are efficacious compared to graduates from a previous 5 year period; had lower odds of believing that many commonly used childhood vaccines were safe; and 3.7% of recent graduates believed that immunizations do more harm than good. Recent health care provider graduates have a perception of the risk-benefit balance of immunization, which differs from that of their older counterparts. This change has the potential to be reflected in their immunization advocacy and affect parental attitudes.
PMCID: PMC4515582  PMID: 26343964
vaccines; health care surveys; health care provider/services
6.  Randomized trial of HPV4 vaccine assessing the response to HPV4 vaccine in two schedules among Peruvian female sex workers 
Vaccine  2012;30(13):2309-2314.
Two hundred female sex workers (FSWs) in Lima, Peru were randomized to receive HPV4 vaccine in the standard (0, 2, 6 months) or a modified schedule (0, 3, 6 months). One hundred and eighty four (92%) participants completed 3 doses of vaccine. Baseline seropositive rates were 58% for HPV6, 22.5% for HPV11, 41.5% for HPV16, and 13% for HPV18. The final geometric mean antibody titer (GMT) following vaccination was significantly greater for women who were seropositive at baseline compared to seronegative women: HPV6 (GMT ratio=2.3, p<0.01), HPV11 (GMT ratio=2.7, p<0.01), HPV16 (GMT ratio=1.3, p=0.04), and HPV18 (GMT ratio=2.4, p<0.01)). Antibody titers in the modified schedule were not inferior to those in the standard schedule, suggesting the modified schedule may be paired with required STD visits. Although all women benefit from vaccination, administration at a younger age and before sexual debut is needed to achieve maximum protection from vaccine.
PMCID: PMC3296898  PMID: 22306855
Human Papillomavirus; HPV vaccine; adherence; immune response; female sex workers; Peru
7.  Missed Clinical Opportunities: Provider Recommendations for HPV Vaccination for 11-12 Year Old Girls is Limited 
Vaccine  2011;29(47):8634-8641.
The purpose of this study was to determine the prevalence of physician recommendation of human papillomavirus (HPV) vaccination in early (ages 11-12), middle (13-17), and late adolescent/young adult (18-26) female patients by physician specialty, and to identify factors associated with recommendation in early adolescents.
A 38-item survey was conducted April 2009 through August 2009 among a nationally representative random sample of 1,538 Family Physicians, Pediatricians, and Obstetricians and Gynecologists obtained from the American Medical Association Physician Masterfile. A multivariable model was used to assess factors associated with frequency of physician recommendation of HPV vaccination (“always”=76-100% of the time vs. other=0-75%) within the past 12 months.
Completed surveys were received from 1,013 physicians, including 500 Family Physicians, 287 Pediatricians, and 226 Obstetricians and Gynecologists (response rate = 67.8%). Across the specialties, 34.6% of physicians reported they “always” recommend the HPV vaccine to early adolescents, 52.7% to middle adolescents, and 50.2% to late adolescents/young adults. The likelihood of “always” recommending the HPV vaccine was highest among Pediatricians for all age groups (P < .001). Physician specialty, age, ethnicity, reported barriers, and Vaccines for Children provider status were significantly associated with “always” recommending HPV vaccination for early adolescents.
Findings suggest missed clinical opportunities for HPV vaccination, and perceived barriers to vaccination may drive decisions about recommendation. Results suggest the need for age and specialty targeted practice and policy level interventions to increase HPV vaccination among US females.
PMCID: PMC3200426  PMID: 21924315
human papillomavirus; HPV vaccine; cancer vaccine; cervix cancer; physician
8.  Parents' Source of Vaccine Information and Impact on Vaccine Attitudes, Beliefs, and Nonmedical Exemptions 
In recent years, use of the Internet to obtain vaccine information has increased. Historical data are necessary to evaluate current vaccine information seeking trends in context. Between 2002 and 2003, surveys were mailed to 1,630 parents of fully vaccinated children and 815 parents of children with at least one vaccine exemption; 56.1% responded. Respondents were asked about their vaccine information sources, perceptions of these sources accuracy, and their beliefs about vaccination. Parents who did not view their child's healthcare provider as a reliable vaccine information source were more likely to obtain vaccine information using the Internet. Parents who were younger, more highly educated, and opposed to school immunization requirements were more likely than their counterparts to use the Internet for vaccine information. Compared to parents who did not use the Internet for vaccine information, those who sought vaccine information on the Internet were more likely to have lower perceptions of vaccine safety (adjusted odds ratio (aOR), 1.66; 95% CI, 1.18–2.35), vaccine effectiveness (aOR, 1.83; 95% CI, 1.32–2.53), and disease susceptibility (aOR, 2.08; 95% CI, 1.49–2.90) and were more likely to have a child with a nonmedical exemption (aOR 3.53, 95% CI, 2.61–4.76). These findings provide context to interpret recent vaccine information seeking research.
PMCID: PMC3469070  PMID: 23082253
9.  Importance of background rates of disease in assessment of vaccine safety during mass immunisation with pandemic H1N1 influenza vaccines 
Lancet  2009;374(9707):2115-2122.
Because of the advent of a new influenza A H1N1 strain, many countries have begun mass immunisation programmes. Awareness of the background rates of possible adverse events will be a crucial part of assessment of possible vaccine safety concerns and will help to separate legitimate safety concerns from events that are temporally associated with but not caused by vaccination. We identified background rates of selected medical events for several countries. Rates of disease events varied by age, sex, method of ascertainment, and geography. Highly visible health conditions, such as Guillain-Barré syndrome, spontaneous abortion, or even death, will occur in coincident temporal association with novel influenza vaccination. On the basis of the reviewed data, if a cohort of 10 million individuals was vaccinated in the UK, 21·5 cases of Guillain-Barré syndrome and 5·75 cases of sudden death would be expected to occur within 6 weeks of vaccination as coincident background cases. In female vaccinees in the USA, 86·3 cases of optic neuritis per 10 million population would be expected within 6 weeks of vaccination. 397 per 1 million vaccinated pregnant women would be predicted to have a spontaneous abortion within 1 day of vaccination.
PMCID: PMC2861912  PMID: 19880172
10.  Bovine and Porcine Gelatin Sensitivity in Milk and Meat-Sensitized Children 
Capsule Summary
Cross-reactive bovine and porcine gelatin-specific IgE antibody is more common in cow’s milk and beef or pork meat-sensitized individuals than previously known and a potential risk factor for allergic reactions to gelatin-containing products (foods, vaccines).
PMCID: PMC2784137  PMID: 19665767
gelatin; porcine; bovine; meat; cow’s milk; IgE antibody; prevalence; cross-reactivity
11.  Effectiveness of measles vaccination and vitamin A treatment 
International Journal of Epidemiology  2010;39(Suppl 1):i48-i55.
Background The current strategy utilized by WHO/United Nations Children's Fund (UNICEF) to reach the Global Immunization Vision and Strategy 2010 measles reduction goal includes increasing coverage of measles vaccine, vitamin A treatment and supplementation in addition to offering two doses of vaccine to all children.
Methods We conducted a systematic review of published randomized controlled trials (RCTs) and quasi-experimental (QE) studies in order to determine effect estimates of measles vaccine and vitamin A treatment for the Lives Saved Tool (LiST). We utilized a standardized abstraction and grading format in order to determine effect estimates for measles mortality employing the standard Child Health Epidemiology Research Group Rules for Evidence Review.
Results We identified three measles vaccine RCTs and two QE studies with data on prevention of measles disease. A meta-analysis of these studies found that vaccination was 85% [95% confidence interval (CI) 83–87] effective in preventing measles disease, which will be used as a proxy for measles mortality in LiST for countries vaccinating before one year of age. The literature also suggests that a conservative 95% effect estimate is reasonable to employ when vaccinating at 1 year or later and 98% for two doses of vaccine based on serology reviews. We included six high-quality RCTs in the meta-analysis of vitamin A treatment of measles which found no significant reduction in measles morality. However, when stratifying by vitamin A treatment dose, at least two doses were found to reduce measles mortality by 62% (95% CI 19–82).
Conclusion Measles vaccine and vitamin A treatment are effective interventions to prevent measles mortality in children.
PMCID: PMC2845860  PMID: 20348126
Measles; vaccine; vitamin A; treatment
12.  Increasing penicillin and trimethoprim-sulfamethoxazole resistance in nasopharyngeal Streptococcus pneumoniae isolates from Guatemalan children, 2001-2006 
We determined nasopharyngeal colonization rates and antibiotic resistance patterns of Streptococcus pneumoniae isolated from Guatemalan children and determined risk factors for colonization and antibiotic nonsusceptibility.
Isolates were obtained from Guatemala City children 5 to 60 months of age attending public and private outpatient clinics and daycare centers during August 2001–June 2002 and outpatient clinics during November 2005–February 2006. Minimal inhibitory concentrations of penicillin, trimethoprim-sulfamethoxazole (TMS), cefotaxime, and erythromycin were determined using E-test.
The overall nasopharyngeal colonization rate for S. pneumoniae was 59.1%. From 2001/2 to 2005/6 TMS nonsusceptibility increased from 42.4% to 60.8% (p<0.05) in public clinics and from 51.4% to 84.0% (p=0.009) in private clinics and penicillin nonsusceptibility increased from 1.5% to 33.3% in public clinics (p<0.001). Reported antibiotic use was not strictly associated with nonsusceptibility to that same antibiotic. Resistance to three or four antibiotics increased in public clinics from 2001/2 (0%) to 2005/6 (10.7%; p<0.001). Risk factors for nasopharyngeal colonization with penicillin- or TMS-nonsusceptible S. pneumoniae were low family income, daycare center attendance, and recent penicillin use.
Increasing antibiotic nonsusceptibility rates in nasopharyngeal S. pneumoniae isolates from Guatemalan children reflect worldwide trends. Policies encouraging more judicious use of TMS should be considered.
PMCID: PMC2430874  PMID: 18035570
antibiotic resistance; erythromycin; cefotaxime; macrolide; cephalosporin; risk factors
13.  The human papillomavirus vaccine and risk of anaphylaxis 
PMCID: PMC2527389  PMID: 18762617
14.  Measles in developing countries 
BMJ : British Medical Journal  2006;333(7581):1234.
Vitamin A and antibiotics prevent complications, but vaccination remains the priority
PMCID: PMC1702417  PMID: 17170396
15.  Support for immunization registries among parents of vaccinated and unvaccinated school-aged children: a case control study 
BMC Public Health  2006;6:236.
Immunizations have reduced childhood vaccine preventable disease incidence by 98–100%. Continued vaccine preventable disease control depends on high immunization coverage. Immunization registries help ensure high coverage by recording childhood immunizations administered, generating reminders when immunizations are due, calculating immunization coverage and identifying pockets needing immunization services, and improving vaccine safety by reducing over-immunization and providing data for post-licensure vaccine safety studies. Despite substantial resources directed towards registry development in the U.S., only 48% of children were enrolled in a registry in 2004. Parental attitudes likely impact child participation. Consequently, the purpose of this study was to assess the attitudes of parents of vaccinated and unvaccinated school-aged children regarding: support for immunization registries; laws authorizing registries and mandating provider reporting; opt-in versus opt-out registry participation; and financial worth and responsibility of registry development and implementation.
A case control study of parents of 815 children exempt from school vaccination requirements and 1630 fully vaccinated children was conducted. Children were recruited from 112 elementary schools in Colorado, Massachusetts, Missouri, and Washington. Surveys administered to the parents, asked about views on registries and perceived utility and safety of vaccines. Parental views were summarized and logistic regression models compared differences between parents of exempt and vaccinated children.
Surveys were completed by 56.1% of respondents. Fewer than 10% of parents were aware of immunization registries in their communities. Among parents aware of registries, exempt children were more likely to be enrolled (65.0%) than vaccinated children (26.5%) (p value = 0.01). A substantial proportion of parents of exempt children support immunization registries, particularly if registries offer choice for participation. Few parents of vaccinated (6.8%) and exempt children (6.7%) were aware of laws authorizing immunization registries. Support for laws authorizing registries and requiring health care providers to report to registries was more common among parents of vaccinated than exempt children. Most parents believed that the government, vaccine companies or insurance companies should pay for registries.
Parental support for registries was relatively high. Parental support for immunization registries may increase with greater parental awareness of the risks of vaccine preventable diseases and utility of vaccination.
PMCID: PMC1592086  PMID: 16995946

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