Catching-up with pentavalent vaccine: Exploring reasons behind lower rotavirus vaccine coverage in El Salvador

Rotavirus vaccine was introduced in El Salvador in 2006 and is recommended to be given concomitantly with DTP–HepB–Haemophilus influenzae type b (pentavalent) vaccine at ages 2 months (upper age limit 15 weeks) and 4 months (upper age limit 8 months) of age. However, rotavirus vaccination coverage continues to lag behind that of pentavalent vaccine, even in years when national rotavirus vaccine stock-outs have not occurred. We analyzed factors associated with receipt of oral rotavirus vaccine among children who received at least 2 doses of pentavalent vaccine in a stratified cluster survey of children aged 24–59 months conducted in El Salvador in 2011. Vaccine doses included were documented on vaccination cards (94.4%) or in health facility records (5.6%). Logistic regression and survival analysis were used to assess factors associated with vaccination status and age at vaccination. Receipt of pentavalent vaccine by age 15 weeks was associated with rotavirus vaccination (OR: 5.1; 95% CI 2.7, 9.4), and receipt of the second pentavalent dose by age 32 weeks was associated with receipt of two rotavirus vaccine doses (OR: 5.0; 95% CI 2.1–12.3). Timely coverage with the first pentavalent vaccine dose was 88.2% in the 2007 cohort and 91.1% in the 2008 cohort (p = 0.04). Children born in 2009, when a four-month national rotavirus vaccine stock-out occurred, had an older median age of receipt of rotavirus vaccine and were less likely to receive rotavirus on the same date as the same dose of pentavalent vaccine than children born in 2007 and 2008. Upper age limit recommendations for rotavirus vaccine administration contributed to suboptimal vaccination coverage. Survey data suggest that late rotavirus vaccination and co-administration with later doses of pentavalent vaccine among children born in 2009 helped increase rotavirus vaccine coverage following shortages.     

Poliovirus immunity in newly resettled adult refugees in Idaho,United States of America

BackgroundIn the United States, vaccines have eliminated wild poliovirus (WPV) infection, though resettling refugees may lack immunity and importation of WPV remains a concern.MethodsA cross-sectional survey was performed to determine the prevalence of poliovirus immunity in adult refugees resettling in Boise, Idaho, U.S.A.; immunity was evaluated using two definitions: serotypes 1, 2 and 3 positive, or serotypes 1 and 3 positive.ResultsThis survey evaluated 795 adult refugees between August 2010 and November 2012. Poliovirus immunity in adults >18 years was 55.3% for serotypes 1, 2 and 3 combined, and 60% for serotypes 1 and 3 only.ConclusionThis study demonstrated a WPV immunity rate of <60% in a recently resettled adult refugee population in the United States, reinforcing the need to ensure poliovirus immunity in all newly arrived adult refugees, either by expanding pre-departure immunization or by screening for immunity at resettlement and vaccinating when indicated.     

Accuracy of administrative claims data to identify dose specific rotavirus vaccination information: Implications for studies of vaccine safety

BackgroundThe accuracy of vaccine administration information recorded in administrative claims databases is uncertain.MethodsWe conducted a retrospective cohort study using the HealthCore Integrated Research Database^SM among infants who received at least 1 RotaTeq^® (RV5) dose during the first year of life between February 1, 2006 and November 30, 2012 and were enrolled in the health plan at birth. We reviewed medical records for a sample of infants to validate vaccine administration information.ResultsWe identified 169,560 infants who received at least 1 RV5 dose. Medical records were obtained for 85 infants, of which 74 (PPV1 87.1%; 95% CI 78.0–93.4%) had a corresponding first RV5 vaccination in the medical record with the same or similar administration date.ConclusionsAdministrative claims contained inaccuracies in dose number or administration date for 13% of RV5 first doses identified.     

Impact of Hepatitis A vaccination with a two-dose schedule in Panama: Results of epidemiological surveillance and time trend analysis

PurposeIn April 2007, Panama introduced Hepatitis A universal vaccination using a two-dose schedule (Havrix^® junior; GSK Vaccines, Belgium). We assessed the impact of this hepatitis A vaccine three years after it was recommended for universal mass vaccination in Panama.Materials and methodsHepatitis A vaccination impact was assessed using two different approaches. The first approach used retrospective data (incidence and number of cases for all age groups), collected from the passive surveillance of the Epidemiologic Surveillance System of the Ministry of Health of hepatitis A and unspecified hepatitis before (2000–2006) and after (2008–2010) introduction of hepatitis A vaccine. The second approach was a prospective hospital-based active surveillance for hepatitis cases conducted in subjects (0–14years) during 2009–2011 at three sentinel hospitals in Panama.ResultsOverall, the annual incidence of hepatitis A and unspecified hepatitis in 2008, 2009 and 2010 were 13.1, 7.9 and 3.7 per 100,000 subjects, lower than the baseline incidence of 51.1 per 100,000 subjects. In comparison to the mean baseline period (2000–2006), there was an 82% mean reduction in the overall hepatitis-related outcomes (hepatitis A and unspecified hepatitis) after vaccine introduction (2008–2010) in all age groups.In the hospital-based surveillance (2009–2011), of the 42 probable viral hepatitis A cases, nine cases were confirmed as acute hepatitis A (8 in 2009, 1 in 2010). Of these confirmed cases, two belonged to the targeted vaccine group (1–4 years) but were not vaccinated.ConclusionsOur study suggests that the introduction of two-dose hepatitis A vaccines in Panama has contributed to the reduction in the incidence of overall hepatitis-related outcomes for all age groups, suggesting herd protection. Additional monitoring is required to document a sustained long-term effect.     

Pneumococcal vaccination in people living with HIV

Streptococcus pneumoniae is the leading bacterial opportunistic infection (OI) in HIV positive individuals. Anti-retroviral treatment (ART) reduces their risk of Invasive Pneumococcal Disease (IPD), however, it remains 20- to 40-fold greater than that of the general population. In HIV-infected adults, pneumococcal vaccination (PCV) induces more durable and functional antibody responses in individuals on ART at the time of vaccination than in ART-naive adults, independently of the baseline CD4+ cell count. National guidelines in the UK recommend vaccination in HIV-infected adults with CD4 count >200 cells/mL and advise that it be considered for those with CD4 count <200 cells/mL³.We report data on IPD from a London HIV cohort of 3500 north-east London patients from 2009 to 2012. IPD was defined as a positive pneumococcal culture from blood, CSF, joint aspirate or pericardial fluid. HIV positive cases were identified by cross-referencing hospital identifiers with a positive HIV Ab/Ag test result or HIV viral load test result on the virology database. There were a total 189 cases of Invasive Pneumococcal Disease identified over the three years. 4.8% (n = 9) were known to be HIV positive at the time of their Invasive Pneumococcal infection. The serotypes of S. pneumoniae in the HIV positive cases included 3, 7F, 10F, 19A (n = 2), 19F and 31. The estimated incidence of IPD in our HIV cohort was 85.7 per 100,000, (based on an overall HIV cohort size of 3500) which is significantly higher when compared to the general population in London (local epidemiological data reported the incidence rate for IPD at 7.5 per 100,000 in London).Given the higher burden of Invasive Pneumococcal Disease in this cohort, low levels of vaccination, and the predominance of vaccine sensitive strains in our cases, vaccination and strategies to improve vaccine uptake is a priority in this at risk group.     

Prevention of perinatal hepatitis B transmission in Haimen City,China: Results of a community public health initiative

In regions where hepatitis B virus (HBV) is endemic, perinatal transmission is common. Infected newborns have a 90% chance of developing chronic HBV infection, and 1 in 4 will die prematurely from HBV-related liver disease. In 2010, the Hepatitis B Foundation and the Haimen City CDC launched the Gateway to Care campaign in Haimen City, China to improve awareness, prevention, and control of HBV infection citywide. The campaign included efforts to prevent perinatal HBV transmission by screening all pregnant women for hepatitis B surface antigen (HBsAg), following those who tested positive, and administering immunoprophylaxis to their newborns at birth. Of 5407 pregnant women screened, 185 were confirmed HBsAg-positive and followed until delivery. At age one, 175 babies were available for follow up testing. Of those, 137 tested negative for HBsAg and positive for antibodies to HBsAg, indicating protection. An additional 34 HBsAg-negative babies also tested negative for antibodies to HBsAg or had indeterminate test results, were considered to have had inadequate immune responses to the vaccine, and were given a booster dose. A higher prevalence of nonresponse to HBV vaccine was observed among babies born to hepatitis B e antigen (HBeAg)-positive mothers and mothers with high HBV DNA titers. The remaining 4 babies tested positive for HBsAg and negative for antibodies, indicative of active HBV infection. The mothers of all 4 had viral loads ≥8 × 10⁶ copies/ml in the third trimester. Although inadequate response or nonresponse to HBV vaccine was more common among babies born to HBeAg-positive and/or high viral load mothers, these risk factors did not completely predict nonresponsiveness. All babies born to HBV-infected mothers should be tested upon completion of the vaccine series to ascertain adequate protection. Some babies of HBeAg-positive mothers with high viral load may still become HBV infected despite timely immunoprophylaxis with HBV vaccine and HBIG.     

Antibody persistence 5 years after vaccination at 2 to 10 years of age with Quadrivalent MenACWY-CRM conjugate vaccine,and responses to a booster vaccination

BackgroundIn a multi-center extension study, children 2–10 years of age, initially vaccinated with one or two doses (2–5 year-olds) or one dose (6–10 year-olds) of quadrivalent meningococcal CRM₁₉₇-conjugate vaccine (MenACWY-CRM), were assessed five years later for antibody persistence and booster response using serum bactericidal assay with human complement (hSBA).MethodsChildren 7–10 and 11–15 years of age, who received MenACWY-CRM in the original study, and age-matched vaccine-naïve children, were enrolled in this extension study. After an initial blood draw, children received one dose of MenACWY-CRM as booster or primary dose, with a second blood draw 28 days later.ResultshSBA titers decreased five years after primary vaccination, but were higher than in non-vaccinated controls against serogroups C, W and Y, with substantial proportions having titers ≥8: 7–22% for A, 32–57% for C, 74–83% for W, and 48–54% for Y. Previously-vaccinated children demonstrated booster responses to revaccination against all four serogroups. Responses to primary vaccination in vaccine-naïve controls were lower and similar to primary responses observed in the original study. All vaccinations were generally well tolerated, with no safety concern raised.ConclusionsApproximately half the children vaccinated as 2–10 year-olds maintained protective antibodies against serogroups C, W and Y five years later, but fewer did against serogroup A. Declining titers five years after vaccination and robust booster responses suggest that five years may be an appropriate interval to revaccinate children, subject to epidemiology and delivery considerations.     

Human papillomavirus vaccine uptake in boys and girls in a school-based vaccine delivery program in Prince Edward Island,Canada

BackgroundIn 2013, Prince Edward Island was the first province to introduce HPV vaccine universally to grade six boys in a school-based program. Because uptake rates in boys are unknown in this type of vaccination program, uptake of HPV vaccination in boys was measured and compared with uptake rates in girls and then analyzed with factors such as county, urban–rural location of the school, and school board to identify where the vaccine program could be improved.MethodsHPV vaccination records from the provincial childhood immunization registry in PEI were merged with Department of Education data containing all grade six girls and boys in PEI. Vaccine uptakes between years and between sexes were compared using two sample tests of proportions. Logistic regression modeling which accounted for the hierarchical nature of the data was used to analyze associations between factors and uptake rates.ResultsAlthough uptake was high in boys and girls, a significantly greater proportion of girls (85%) received all three doses of the HPV vaccine compared to boys (79%; p = 0.004). The odds of grade six girls being fully vaccinated for HPV were 1.5 times greater than of grade six boys, and the odds of students in the English Language School Board receiving all three doses were more than twice as great as the odds of French Language School Board students.ConclusionsHPV vaccination for boys in PEI has had a successful launch, almost reaching the Canadian Immunization Committee recommendations of >80% for the early years of a program. PEI has a highly organized Public Health Nursing program that is involved in all childhood and school-based vaccinations in PEI and in this context very high coverage rates were obtained. Areas to target for improving uptake include the boys and the students in the French Language School Board.     

Pneumococcal vaccination coverage among persons ≥65 years—United States, 2013

BackgroundInvasive pneumococcal disease is a major cause of illness in the United States, and rates are higher among persons ≥65 years. Pneumococcal vaccination has been recommended to adults ≥65 years since 1997.MethodsData from the 2005–2013 Behavioral Risk Factor Surveillance System were analyzed. Weighted estimates of pneumococcal vaccination coverage were calculated by state and race/ethnicity and tests for linear trend were performed.ResultsIn 2013, the median state vaccination coverage among adults ≥65 years was 69.5%, and coverage ranged from 61.9% in New Jersey to 75.6% in Oregon. Coverage overall among non-Hispanic whites (71.1%) was higher than coverage for non-Hispanic blacks (57.7%), Hispanics (51.9%), and non-Hispanic persons of other race (65.4%). Coverage increased from 2005 to 2013 overall and by racial/ethnic subgroups.ConclusionAlthough pneumococcal vaccination coverage has improved in the past several years, coverage remains below the Healthy People 2020 target of 90% and racial/ethnic disparities exist.