Cumulative Vaccine Coverage Research Articles

Even though active recommendation for HPV vaccination has restarted, Japan's rates have not recovered.

Japan has a particularly critical situation surrounding its collapsed HPV vaccination program for preventing HPV-caused cervical cancers, a problem exacerbated by the lack of a national immunization database. We have determined the year-to-year HPV vaccination uptake by Japanese females and analyzed by birth fiscal year (FY) the monthly number of people receiving initial HPV vaccination. Our analysis covers the period from the start of public subsidies in 2010 to September 2023, using data provided by local governments. We calculated the cumulative number of monthly immunizations for those unimmunized as of April (the beginning of each vaccination year). The monthly number of initial HPV vaccinations was highest in August for every FY from FY 2010 to FY 2023; a second vaccination peak tended to occur in March when the vaccination year ended. The highest number of August vaccinations occurred in FY 2011, followed (in order) by 2012, 2021, 2022, 2023, and 2013. In Japan's ongoing catch-up vaccination program for young women, the monthly number of vaccinations increased in August 2022 but then slowed the following year. After FY 2021, the cumulative vaccination coverage of subjects unvaccinated at the beginning of the vaccination year but subsequently covered by routine immunizations was slightly improved. FY 2021 was when the governmental recommendations for HPV vaccination were resumed. More recent vaccination rates are considerably lower than those in FY 2011-2012 when vaccinations were first fully endorsed. Paralyzing HPV vaccination hesitancy, which began in FY 2013, will linger in Japan in FY 2024.

Patterns in COVID-19 vaccination among children aged 5–11 years in Alberta, Canada: Lessons for future vaccination campaigns

ObjectivesIn Alberta, Canada, the COVID-19 vaccination program for children aged 5–11 years was launched on November 26, 2021. Our objectives were to determine the cumulative vaccine coverage, stratified by age, during the first thirteen months of vaccine availability, and investigate factors associated with vaccine uptake. Study designThis retrospective cohort study used population-based administrative health data. MethodsWe determined cumulative vaccine coverage among 5–11 year olds, stratified by year of age, during the first thirteen months of vaccine availability and used a modified Poisson regression to evaluate factors associated with vaccine uptake. ResultsOf 377,103 eligible children, 44.8 % (n = 168,761) received one or more doses of COVID-19 vaccine during the study period (9.7 % received only one dose, while 35.1 % received 2 doses). Almost 90 % of initial doses were received within the first two months of vaccine availability. We found a step-wise relationship between increasing child age and higher vaccine coverage. ConclusionsPlateaued vaccine uptake indicates a need to adapt programmatic efforts to encourage parents to act on positive vaccination intentions, and reach the large contingent of parents who have reported that they remain undecided. In order to promote vaccine uptake, messaging around vaccine safety and need should be tailored to child age, rather than uniformly applied across the 5–11 year age range.

Factors associated with COVID-19 vaccine uptake in people with kidney disease: an OpenSAFELY cohort study

ObjectiveTo characterise factors associated with COVID-19 vaccine uptake among people with kidney disease in England.DesignRetrospective cohort study using the OpenSAFELY-TPP platform, performed with the approval of NHS England.SettingIndividual-level routine clinical...

Changing characteristics over time of individuals receiving COVID-19 vaccines in Denmark: A population-based descriptive study of vaccine uptake.

The Danish authorities implemented a differential rollout of the COVID-19 vaccines where individuals at high risk of COVID-19 were prioritized. We describe the temporal uptake and characteristics of COVID-19 vaccine recipients in Denmark. Using nationwide healthcare registries, we identified all Danish residents ⩾5 years of age who received at least one dose of a COVID-19 vaccine from 27 December 2020-29 January 2022. We charted the daily number of newly vaccinated individuals and the cumulative vaccine coverage over time, stratified by vaccine type, age groups and vaccination priority groups, and described characteristics of vaccine recipients during two-month-intervals and in vaccination priority groups. By 29 January 2022, 88%, 86% and 64% of Danish residents ⩾5 years (n=5,562,008) had received a first, second and third dose, respectively, of a COVID-19 vaccine, most commonly the BNT162b2 vaccine (84%). Uptake ranged from 48% in 5-11-year-olds to 98% in 65-74-year-olds. Individuals vaccinated before June 2021 were older (median age 61-70 years vs 10-35 years in later periods) and had more comorbidities such as hypertension (22-28% vs 0.77-2.8% in later periods), chronic lung disease (9.4-15% vs 3.7-4.6% in later periods) and diabetes (9.3-12% vs 0.91-2.4% in later periods). We document substantial changes over time in, for example, age, sex and medical history of COVID-19 vaccine recipients. Though these results are related to the differential vaccine rollout in Denmark, similar findings are probable in other countries and should be considered when designing and interpreting studies on the effectiveness and safety of COVID-19 vaccines.

SARS-CoV-2 Variant Tracking and Mitigation During In-Person Learning at a Midwestern University in the 2020-2021 School Year

The COVID-19 pandemic led many higher education institutions to close campuses during the 2020-2021 academic year. As campuses prepared for a return to in-person education, many institutions were mandating vaccines for students and considering the same for faculty and staff. To determine the association between vaccination coverage and the levels and spread of SARS-CoV-2, even in the presence of highly-transmissible variants and congregate living, at a midsized university in the US. This case series was conducted at a midsized Midwestern university during the spring 2021 semester. The university developed a saliva-based surveillance program capable of high-throughput SARS-CoV-2 polymerase chain reaction testing and genomic sequencing with the capacity to deliver results in less than 24 hours. On April 7, 2021, the university announced a vaccine requirement for all students for the fall 2021 semester and announced the same requirement for faculty and staff on May 20, 2021. The university hosted an onsite mass vaccination clinic using the 2-dose Pfizer-BioNTech vaccine during April 8 to 15 and April 29 to May 6, 2021. Data were analyzed for 14 894 individuals from the university population who were tested for COVID-19 on campus from January 6 to May 20, 2021. Positive SARS-CoV-2 diagnosis was confirmed by quantitative reverse transcription-polymerase chain reaction of saliva specimens, and variant identity was assessed by quantitative reverse transcription-polymerase chain reaction and next-generation sequencing of viral genomes. Between January 6 and May 20, 2021, the university conducted 196 185 COVID-19 tests for 14 894 individuals and identified 1603 positive cases. Within those positive cases, 950 individuals (59.3%) were male, 644 (40.2%) were female, 1426 (89.0%) were students, and 1265 (78.9%) were aged 17 to 22 years. Among the 1603 positive cases, 687 were identified via polymerase chain reaction of saliva specimens. The Alpha (B.1.1.7) variant constituted 218 of the 446 total positives sequenced (48.9%). By May 20, 2021, 10 068 of 11 091 students (90.8%), 814 of 883 faculty (92.2%), and 2081 of 2890 staff (72.0%) were vaccinated. The 7-day rolling average of positive cases peaked at 37 cases on February 17 but declined to zero by May 14, 2021. The 7-day moving average of positive cases was inversely associated with cumulative vaccination coverage, with a statistically significant Pearson correlation coefficient of -0.57 (95% CI, -0.68 to -0.44). This case series study elucidated the association of a robust vaccination program with a statistically significant decrease in positive COVID-19 cases among the study population even in the presence of highly transmissible variants and congregate living.

HPV vaccination coverage in women between 15 and 55years old in Spain: Temporal trend during the period 2007-2020.

The objective of this study was to analyse the temporal trend of HPV vaccination coverage (VC) in Spain in women aged 15-55 years not included in systematic vaccination programmes during the period 2007-2020. We assessed the vaccine coverage rate in this population based on three estimations: 1) annual vaccination coverage with at least one dose (VCR≥1d), 2) annual VC for the full schedule (VCR3d), and 3) cumulative VC for the full schedule (aVCR). Annual VCR≥1d and VCR3d were highest in 2008 (2.40% and 0.66% respectively) and subsequently decreased drastically in 2011 (0.55% and 0.15%). From 2017 to 2019 there was an increase from 1.4-fold to 1.6-fold, respectively, which decreased in 2020. In relation to aVCR, there was an increasing trend throughout the study period with approximately 4.03% of the study population having been vaccinated against HPV in 2020. In Spain, the cumulative vaccination coverage against HPV in women between 15-55 years old not included in current vaccination programmes remains very low. Nonetheless, the temporal trend has shown a slight increase in recent years. Despite the COVID-19 pandemic in 2020, no significant negative impact on vaccination coverage has been observed in this population.

Impact of the COVID-19 pandemic on vaccine coverage for early childhood vaccines in Alberta, Canada: a population-based retrospective cohort study

ObjectiveTo assess the impact of the COVID-19 pandemic on early childhood vaccination coverage in Alberta, Canada.SettingAlberta, a western Canadian province, which has a population of 4.4 million and approximately 50...

Low vaccination coverage of pneumococcal conjugate vaccines (PCVs) in Shanghai, China: A database analysis based on birth cohorts from 2012 to 2020

BackgroundPneumococcal vaccines have been developed to protect infants and young children from pneumococcal diseases. Vaccination coverage studies are important in determining a population’s vaccination status and strategically adjusting national immunization programs (NIP). In this paper, we aim to describe the coverage of pneumococcal conjugate vaccines (PCVs) immunization for birth cohorts from 2012 to 2020 and discussed the factors influencing the coverage. MethodsVaccination data were collected via the vaccination information database in Shanghai, China, for children born from 2012 to 2020. The population data used in this study were collected from each community from 2012 to 2020. The coverage of initial immunization (1st dose), basic immunization (three doses) and full immunization (3 + 1 doses) for PCVs was calculated according to the number of doses received. As vaccination coverage was assessed each year, Annual Growth Rate (AGR) was used to describe the variation trend of vaccination coverage. Immunization time and completeness of different PCVs were also analyzed. ResultsThe total number of births from 2012 to 2020 was 38,268 in Huangpu District, Shanghai, China. The initial immunization coverage of PCVs increased from 12.26% in 2012 to 49.65% in 2020, and the highest coverage was 50.61% in 2019. The cumulative vaccination coverage of PCVs was 19.4% for initial immunization and 16.8% for basic immunization from 2012 to 2020. And cumulative full immunization coverage of PCVs was 12.3% from 2012 to 2019. The PCVs coverage of most vaccination statuses showed an obvious upward trend from 2017 to 2020. ConclusionsDespite an upward trend in vaccination coverage of PCVs, the vaccination coverage of initial, basic and full immunization among children is still low. And given the heavy burden of Streptococcus pneumoniae (Sp) among children in China and the fact that the current vaccination coverage cannot effectively protect children, it is recommended that the government include PCVs into the NIP as soon as possible.

Alternative Methods for Grouping Race and Ethnicity to Monitor COVID-19 Outcomes and Vaccination Coverage.

Population-based analyses of COVID-19 data, by race and ethnicity can identify and monitor disparities in COVID-19 outcomes and vaccination coverage. CDC recommends that information about race and ethnicity be collected to identify disparities and ensure equitable access to protective measures such as vaccines; however, this information is often missing in COVID-19 data reported to CDC. Baseline data collection requirements of the Office of Management and Budget's Standards for the Classification of Federal Data on Race and Ethnicity (Statistical Policy Directive No. 15) include two ethnicity categories and a minimum of five race categories (1). Using available COVID-19 case and vaccination data, CDC compared the current method for grouping persons by race and ethnicity, which prioritizes ethnicity (in alignment with the policy directive), with two alternative methods (methods A and B) that used race information when ethnicity information was missing. Method A assumed non-Hispanic ethnicity when ethnicity data were unknown or missing and used the same population groupings (denominators) for rate calculations as the current method (Hispanic persons for the Hispanic group and race category and non-Hispanic persons for the different racial groups). Method B grouped persons into ethnicity and race categories that are not mutually exclusive, unlike the current method and method A. Denominators for rate calculations using method B were Hispanic persons for the Hispanic group and persons of Hispanic or non-Hispanic ethnicity for the different racial groups. Compared with the current method, the alternative methods resulted in higher counts of COVID-19 cases and fully vaccinated persons across race categories (American Indian or Alaska Native [AI/AN], Asian, Black or African American [Black], Native Hawaiian or Other Pacific Islander [NH/PI], and White persons). When method B was used, the largest relative increase in cases (58.5%) was among AI/AN persons and the largest relative increase in the number of those fully vaccinated persons was among NH/PI persons (51.6%). Compared with the current method, method A resulted in higher cumulative incidence and vaccination coverage rates for the five racial groups. Method B resulted in decreasing cumulative incidence rates for two groups (AI/AN and NH/PI persons) and decreasing cumulative vaccination coverage rates for AI/AN persons. The rate ratio for having a case of COVID-19 by racial and ethnic group compared with that for White persons varied by method but was <1 for Asian persons and >1 for other groups across all three methods. The likelihood of being fully vaccinated was highest among NH/PI persons across all three methods. This analysis demonstrates that alternative methods for analyzing race and ethnicity data when data are incomplete can lead to different conclusions about disparities. These methods have limitations, however, and warrant further examination of potential bias and consultation with experts to identify additional methods for analyzing and tracking disparities when race and ethnicity data are incomplete.

Human papillomavirus (HPV) vaccine coverage rates (VCRs) in France: A French claims data study

BackgroundThe French Cancer Plan 2014–2019 had a target of 60% HPV vaccine coverage. The PAPILLON study investigated the annual age-specific vaccination initiation rates and cumulative partial and complete vaccination rates in France from 2017 to 2022. It also identified the factors associated with vaccination in different age groups and those associated with the type of completion of the vaccination scheme (partial vs full vaccination). MethodsFor this publication, all females recorded in the French National Claims database who initiated HPV vaccination between 1 July 2007 and 31 December 2018 and were aged between 11 and 19 years at initiation were included. Annual HPV vaccination initiation rates were estimated in 11- to 14-year-old (target population) and 15- to 19-year-old females (catch-up). Cumulative vaccine coverage rates (VCRs) were estimated among those who were 15, 16, 20 and 21 years old. Partial vaccination was defined by dispensing of at least one dose of HPV vaccine by the pharmacy, while full vaccination was defined by two or three doses dispensed by a pharmacy over an 18-month period, according to current French recommendations based on the age at vaccination initiation. ResultsAmong the 465,629 females who initiated HPV vaccination in 2017 or 2018, the initiation rate increased from 7.7 to 11.1% in 11- to 14-year-old girls and from 4.5 to 6.5% in 15- to 19-year-old females. In 2017 and 2018, the cumulative VCRs for partial vaccination by age 15 were 28.2% and 32.8%, respectively, while by age 20, they were 41.6% and 38.8%. The cumulative VCRs for full vaccination were 15.6% and 18.6% by age 16, while they were 25.9 and 23.6% by age 20. HPV vaccination initiation and completion were strongly associated with the use of health services. ConclusionOverall, the HPV VCR substantively increased between 2017 and 2018, which is positive evidence of the resumption of vaccination. Updates in 2022 should confirm these results.

Cumulative annual coverage of meningococcal B vaccination in Australian general practice for three at-risk groups, 2014 to 2019

ABSTRACT Neisseria meningitidis serogroup B (MenB) is the most common cause of meningococcal disease in adolescents and young adults. In Australia, MenB vaccination has been available through private prescription since 2014 and has been recommended for at-risk groups including adolescents, young adults who smoke and people medically at risk. For each of these at-risk groups, we estimated cumulative annual coverage of MenB vaccination between 2014 and 2019. We also evaluated factors associated with vaccination coverage in 2019. Our analyses used electronic health records in the national MedicineInsight database for people regularly attending general practices. Cumulative vaccination coverage increased among the at-risk groups between 2014 and 2019: from 0.09% to 1.65% for adolescents, from 0.01% to 0.15% for young adults who smoke, and from 0.35% to 12.09% for people medically at risk. However, vaccination coverage in 2019 remained very low across these groups. Data sparsity prevented the evaluation of factors associated with vaccination coverage for smokers. We observed variation in the relative risk of being vaccinated by age, sex, socioeconomic and clinical factors for adolescents and people medically at risk. Still, the absolute magnitude of coverage was low across all subgroups examined, and indicates a need for strategies to increase vaccination uptake among at-risk groups irrespective of patient and practice characteristics. Our study provides baseline data for monitoring menB vaccination uptake among recommended groups in light of limited national data, especially for medically at-risk groups.

Impact of Vaccination on the COVID-19 Pandemic: Evidence from U.S. States

Governments worldwide are implementing mass vaccination programs in an effort to end the novel coronavirus (COVID-19) pandemic. Although the approved vaccines exhibited high efficacies in randomized controlled trials, their population effectiveness in the real world remains less clear, thus casting uncertainty over the prospects for herd immunity. In this study, we evaluated the effectiveness of the COVID-19 vaccination program and predicted the path to herd immunity in the U.S. Using data from 12 October 2020 to 7 March 2021, we estimated that vaccination reduced the total number of new cases by 4.4 million (from 33.0 to 28.6 million), prevented approximately 0.12 million hospitalizations (from 0.89 to 0.78 million), and decreased the population infection rate by 1.34 percentage points (from 10.10% to 8.76%). We then built a Susceptible-Infected-Recovered (SIR) model with vaccination to predict herd immunity. Our model predicts that if the average vaccination pace between January and early March 2021 (2.08 doses per 100 people per week) is maintained, the U.S. can achieve herd immunity by the last week of July 2021, with a cumulative vaccination coverage of 60.2%. Herd immunity could be achieved earlier with a faster vaccination pace, lower vaccine hesitancy, or higher vaccine effectiveness. These findings improve our understanding of the impact of COVID-19 vaccines and can inform future public health policies regarding vaccination, especially in countries with ongoing vaccination programs.

Herpes zoster vaccine coverage in Australia before and after introduction of a national vaccination program

BackgroundIn Australia, a herpes zoster (HZ) vaccination program targeting adults aged 70 years old with catch-up for those 71-79 years began in November 2016 but there is limited information on vaccine uptake and coverage achieved since commencement. MethodsWe used a national de-identified electronic primary care dataset, MedicineInsight, and extracted records from patients turning 50–90 years old during 2016–2018. Among patients considered regular attenders, with at least one visit per year in the two years prior, we estimated the crude and adjusted average monthly HZ vaccine uptake in the target population (70–79 years old) for each year since program implementation as well as cumulative vaccine coverage until December 2018. Multivariate logistic regression was used to analyse characteristics associated with higher coverage. ResultsAmong 52,229, 55,034, and 57,316 regular attenders turning 70–79 years old in 2016, 2017 and 2018 respectively, the average monthly vaccine uptake rate was 5.5%, 3.3%, and 1.6% respectively. Up to 31st December 2018, the estimated cumulative vaccine coverage in regularly attending adults was 46.9% (25,791/55,034). It was substantially lower at 41.6% (27,040/65,010) using an alternate definition of a regular attender. Vaccine coverage differed by sex (women: 48.5% versus men: 45.1%, adjusted OR = 1.1, 95% CI: 1.1–1.2); by jurisdiction (compared to New South Wales: 43.7%, South Australia: 55.6%, aOR = 1.6, 95% CI (1.5–1.8); Northern Territory: 27.6%, aOR = 0.6, (0.5–0.7)); by remoteness status (compared to major cities: 47.6%, remote/very remote areas: 38.2%, aOR = 0.7, (0.6–0.8)); and by socioeconomic disadvantage (compared to most disadvantaged: 41.8%, most advantaged: 48.6%, aOR = 1.6 (1.2–2.1)). ConclusionsOur estimates of HZ vaccine coverage are substantially higher than the only other reports based on the Australian Immunisation Register however they still suggest that uptake is suboptimal. The use of electronic medical records can complement other data for estimating vaccine coverage in Australian adults.

2742. The Impact of Influenza Vaccination on Antibiotic Use in the United States, 2010–2017

BackgroundAntibiotic resistance is a cause of morbidity and mortality driven by inappropriate prescribing. In the United States, a third of all outpatient antibiotic prescriptions may be inappropriate. Seasonal influenza rates are significantly associated with antibiotic prescribing rates. The impact of influenza vaccination coverage on antibiotic prescribing is unknown.MethodsWe conducted a retrospective analysis of state-level vaccination coverage and antibiotic prescribing rates from 2010 to 2017. We used fixed effects regression to analyze the relationship between cumulative vaccine coverage rates for a season and the per capita number of prescriptions for systemic antibiotics for the corresponding season (January–March) controlling for temperature, poverty, healthcare infrastructure, population structure, and vaccine effectiveness.ResultsRates of vaccination coverage ranged from 33% in Nevada to 52% in Rhode Island for the 2016–2017 season, while antibiotic use rates ranged from 25 prescriptions per 1,000 inhabitants in Alaska to 377 prescriptions per 1,000 inhabitants in West Virginia (Figure 1). Vaccination coverage rates were highly correlated with reduced prescribing rates, and controlling for other factors, we found that a one percent increase in the influenza vaccination rate was associated with 1.40 (95% CI: 2.22–0.57, P < 0.01) fewer antibiotic prescriptions per 1,000 inhabitants (Table 1). Increases in the vaccination coverage rate in the pediatric population (aged 0–18) had the strongest effect, followed by the elderly (aged 65+).ConclusionVaccination can reduce morbidity and mortality from seasonal influenza. Though coverage rates are far below levels necessary to generate herd immunity, we found that higher coverage rates in a state were associated with lower antibiotic prescribing rates. While the effectiveness of the vaccine varies from year to year and the factors that drive antibiotic prescribing rates are multi-factorial, these results suggest that increased vaccination coverage for influenza would have significant benefit in terms of reducing antibiotic overuse and correspondingly antibiotic resistance. Disclosures All authors: No reported disclosures.

Low tetanus-diphtheria-acellular pertussis (Tdap) vaccine coverage among healthcare workers in a quaternary university hospital in São Paulo, Brazil: need for continuous surveillance and implementation of active strategies

IntroductionVaccination with tetanus-diphtheria-acellular pertussis (Tdap) has been recommended for healthcare workers (HCWs) by Brazilian Ministry of Health since November 2014. ObjectiveTo describe the strategies implemented to improve Tdap uptake, cumulative vaccine coverage after each intervention, variables associated to Tdap vaccination, and reasons for non-vaccination among HCWs of the main building of a quaternary hospital attached to the Sao Paulo University Medical School. MethodsA list of HCWs eligible for pertussis vaccination was generated. From April to December 2015, the following interventions were implemented: note on intern journal reminding the importance of pertussis vaccination; email to the head nurses strengthening vaccine recommendations; lectures on pertussis and Tdap for physicians of Obstetrics and Neonatology Clinics; on-site vaccination by mobile teams at the Obstetrics, Neonatology, and Anesthesiology Clinics. Vaccine coverage was accessed at the end of each month. Multivariate Poisson regression model with a robust error variance was used to evaluate variables associated with Tdap vaccination. Reasons for non-vaccination were evaluated from January to May 2017 through phone calls for HCWs who had not received Tdap. ResultsThe study included 456 HCWs. After the interventions, Tdap coverage raised from 2.8% to 41.2%. In the multivariate analysis, occupation (physician), working place (obstetrics or anesthesiology) and influenza vaccination in 2015 were independently associated to Tdap vaccination. The main reason for non-vaccination was unawareness of Tdap recommendations. ConclusionsTdap uptake among HCWs was low in our hospital. Providing vaccination at convenient places/times for HCW seems to be the most efficient strategy to increase vaccine uptake.

Association of Pneumococcal Conjugate Vaccine Coverage With Pneumococcal Meningitis: An Analysis of French Administrative Areas, 2001-2016.

Geographic variations of invasive pneumococcal disease incidence and serotype distributions were observed after pneumococcal conjugate vaccine introduction at regional levels and among French administrative areas. The variations could be related to regional vaccine coverage (VC) variations that might have direct consequences for vaccination-policy impact on invasive pneumococcal disease, particularly pneumococcal meningitis (PM) incidence. We assessed vaccine impact from 2001 to 2016 in France by estimating the contribution of regional VC differences to variations of annual local PM incidence. Using a mixed-effect Poisson model, we showed that, despite some variations of VC among administrative areas, vaccine impact on vaccine-serotype PM was homogeneously confirmed among administrative areas. Compared with the prevaccine era, the cumulative VC impact on vaccine serotypes led, in 2016, to PM reductions ranging among regions from 87% (25th percentile) to 91% (75th percentile) for 7-valent pneumococcal conjugate vaccine serotypes and from 58% to 63% for the 6 additional 13-valent pneumococcal conjugate vaccine serotypes. Nonvaccine-serotype PM increases from the prevaccine era ranged among areas from 98% to 127%. By taking into account the cumulative impact of growing VC and VC differences, our analyses confirmed high vaccine impact on vaccine-serotype PM case rates and suggest that VC variations cannot explain PM administrative area differences.

The varicella vaccination pattern among children under 5 years old in selected areas in China.

BackgroundVaccine is the most effective way to protect susceptible children from varicella. Few published literature or reports on varicella vaccination of Chinese children exist. Thus, in order to obtain specific information on varicella vaccination of this population, we conducted this survey.MethodologyWe first used purposive sampling methods to select 6 provinces 10 counties from eastern, middle and western parts of China with high quality of Immunization Information Management System (IIMS), and then randomly select children from population in the IIMS, then we checked vaccination certificate on-site.Principal FindingsBased on the varicella vaccination information collected from 481 children's vaccination certificates from all ten selected counties in China, overall coverage of the first dose of varicella vaccine was 73.6%. There is a positive linear correlation between per capita GDP and vaccine coverage at county level (r=0.929, P < 0.01). The cumulative vaccine coverage among children at 1 year, 2 years and ≥3 years old were 67.6%, 71.9% and 73.6% respectively (X2=4.53, P =0.10). The age of vaccination was mainly concentrated in 12-17 months.ConclusionsThe coverage rate of the first dose of varicella vaccine in selected areas was lower than that recommended by WHO position paper. The coverage rate was relatively low in areas of low social-economic status. The cumulative coverage had no significant statistical difference among different age group. Most children received varicella vaccine before 3 years old. We suggest introducing the varicella vaccine into routine immunization program, to ensure universal high coverage among children in China. We also suggest that varicella vaccination information should be checked before entering school, in order to control and prevent varicella outbreaks in schools.

Efficacy of vaccination against HPV infection to prevent cervical cancer in France

Human papillomavirus (HPV) types 16 and 18 cause 70% of cervical cancers, and currently two vaccines protecting against these types are available. In a previous paper, we estimated the long-term effect of HPV vaccination on the risk of cervical cancer in the French population using mathematical modeling. Several vaccination scenarios were tested, including different vaccination coverage rates of females alone or in conjunction with males. In the first scenario, which is based on the vaccination campaign initiated in France in 2007, 30% of females aged 14 to 19 years were vaccinated annually, resulting in a 60% cumulative vaccination coverage rate among 14 to 19 year old females 6 years after the beginning of the vaccination campaign. A catch-up program was also included with an annual vaccination rate of 10% among females aged 20 to 24 years. Using this scenario, the model predicted an 83% reduction in cervical cancer incidence 50 years after vaccination initiation. The following scenarios were also considered: extending vaccination: (1) to males, (2) to females under 14; and scenarios with (3) vaccination among 14 to 24 year-old females (annual rate of 80%), (4) vaccination among 14 to 24 year-old females and males (annual rate of 80%). Greater reductions in cervical cancer incidence of 92% to 98% were predicted.

Japan’s Vaccine Service and an Introduction to the History of Cumulative Vaccine Coverage

During the measles epidemic periods in 1999-2003, a research group elaborated a method of estimating vaccination coverage. The objective of cumulative vaccination coverage (CVC) was to estimate the age of vaccine completion for vaccine targets in an age cohort. From randomly selected children of an age cohort, vaccine records including the date of birth and date of vaccine administration were retrieved, allowing for the calculation of the age of vaccine targets. By acquiring this information, it is possible to derive vaccination trends by age. According to the literature, CVC is now more widely applied and is used for monitoring delays of vaccination due to changes of the vaccine administration schedule and schedule interaction when newly-introduced vaccines are implemented. Although CVC is rather costly because it requires random sampling, we conclude that it is a useful method for estimating herd immunity.

麻疹ワクチン及びポリオ生ワクチン累積接種率全国調査結果

In 2002 we estimated the measles cumulative vaccination coverage (CVC) in Japan by randomly selecting a total of 5,000 3-year-old children from the total Japanese population and examining the age in months when they were vaccinated against measles. This survey revealed that in Japan measles CVC at ages 18, 24, and 36 months were 61.7 +/- 1.6%, 79.6 +/- 1.3%, and 86.9 +/- 1.1%, respectively. The results obtained in 2003 revealed that the measles CVC among 3-year-old children in 2003 was higher than that obtained in 2002, with especially noticeable improvement in their period of 12 to 23 months of age. It is estimated that this improvement was attributed to the effort made by many persons concerning vaccination to raise the vaccination rate. In 2003 oral polio vaccine (OPV) CVC was investigated for the first time, in addition to measles CVC. OPV CVC of the first dose at 6, 12, and 36 months of age were 44.2 +/- 1.5%, 85.5 +/- 1.1%, and 94.7 +/- 0.8%, respectively. The results of the second dose at 12, 18, and 36 months of age were 42.3 +/- 1.5%, 73.5 +/- 1.3%, and 90.7 +/- 0.9%, respectively. Even at 36 months of age the CVC level of the second dose of OPV was found to be slightly lower than that of the first dose.