The immunological effect of revaccination with Bacille Calmette-Guérin vaccine at 19 months of age

Background

Bacille Calmette-Guérin (BCG) vaccination has important non-specific immune effects. In a randomized trial in Guinea-Bissau, BCG revaccination was associated with significantly increased survival in children who received diphtheria-tetanus-pertussis (DTP)-booster vaccine before enrolment and in children who did not receive micronutrient supplementation (MN). Within the trial we assessed the immunological effects of BCG revaccination.

Methods

Children were randomized to BCG or nothing. Blood was sampled 6–11 weeks after randomization (early sample group) or 5–9 months later (late sample group). In vitro cytokine responses (interferon (IFN)-γ, interleukin (IL)-13, tumor-necrosis-factor (TNF)-α, and IL-10) were assessed in whole blood cultures stimulated with lipopolysaccharide (LPS), purified protein derivative (PPD) or phytohaemagglutinin (PHA). Effect-modification by sex, DTP-booster vaccination and MN was studied.

Results

Cytokines were measured in 345 infants. BCG was associated with significantly increased IFN-γ (geometric mean ratio (GMR) = 4.54 (95% confidence interval: 3.13–6.58)) and IL-13 (GMR = 1.43 (1.00–2.05)) PPD responses, the effect being strongest in the early sample group. Across all three conditions BCG tended to increase IL-10 (LPS, PHA, PPD: GMR = 1.20, 1.12, 1.20), most pronounced in the late sample group. BCG reduced the TNF-α/IL-10 ratio in boys with DTP-booster at bleeding and increased it in those without (interaction test: p = 0.03). In children without MN, BCG was associated with reduced TNF-α response in the early sample group (p = 0.006), and increased IL-10 in the late sample group (p = 0.03).

Conclusion

BCG revaccination resulted in a strong IFN-γ response to PPD, which waned slightly over time. BCG also affected the pro-/anti-inflammatory balance, with reduced TNF-α and increased IL-10 responses to LPS, PHA and PPD. This effect depended on sex, DTP-booster vaccination and micronutrient supplementation, being most pronounced in children who had received DTP-booster before enrolment and children who had not received MN, i.e. the group of children which also had lower mortality after BCG revaccination.     

Vaccination status and sequence of vaccinations as risk factors for hospitalisation among outpatients in a high mortality country

Background

Most developing countries are implementing the WHO immunisation programme. Although vaccines reach most children, many modifications of the recommended schedule are observed in practice. We investigated the association between vaccination status and risk of hospitalisation in Guinea-Bissau.

Methods

From May 2003 to May 2004, all consultations of children less than five years of age at the outpatient clinic of the paediatric ward at the national hospital in Bissau were registered. For each consultation, information was collected about the child's name, sex, age and socio-cultural conditions, as well as diagnosis and whether the child was hospitalised. Information about vaccinations was also registered from the child's vaccination card. We analysed the association between vaccination status and risk of hospitalisation in age intervals according to the pre-dominant vaccines. We particularly emphasised the comparison of those who had received the recommended vaccination for the age groups and those who were delayed and only had the previous vaccinations. We also examined those who had received the vaccines out of sequence.

Results

Information about vaccinations was available for 11,949 outpatient children of whom 2219 (19%) were hospitalised. Among children less than 3 months of age, unvaccinated children compared to BCG children had as expected a higher risk of hospitalisation; controlled for important determinants of hospitalisation, the hospitalisation risk ratio (HRR) was 1.99 (95% CI 1.37-2.89). In contrast, there was no difference in the HRR for children aged 1 ½ -8 months who were delayed and had only received BCG compared to those who as recommended had received diphtheria-tetanus-pertussis (DTP) vaccine after BCG (HRR = 1.10 (0.77-1.59)). In the age interval 9-17 months of age, children who were delayed and had only received DTP had significantly higher risk of hospitalisation compared with children who as recommended had measles vaccine (MV) as the most recent vaccination (HRR = 1.39 (1.16-1.66)). Having received DTP after MV (HRR = 1.60 (1.15-2.24)) or MV and DTP simultaneously (HRR = 1.51 (1.16-1.97)) was also associated with higher risk than MV only as most recent vaccination. In contrast, the children aged 18-59 months who as recommended had received a DTP booster after MV did not have lower risk of hospitalisations compared with children who were delayed and had received only MV (RR = 0.90 (0.75-1.07)). After 9 months of age, there was a significant difference in the female-male HRR for children who had MV (HRR = 0.85 (0.72-1.00)) or DTP (HRR = 1.08 (0.96-1.22)) as most recent vaccination (p = 0.02, test of interaction).

Conclusion

Following the recommended vaccination schedule for BCG and MV is associated with a reduced risk of hospitalisation but this is not the case for DTP and booster DTP. Receiving DTP simultaneously with MV or after MV is associated with increased risk of hospitalisation. Vaccines have sex-differential effects on the risk of hospitalisation.     

Socio-demographic determinants of timely adherence to BCG,Penta3, measles,and complete vaccination schedule in Burkina Faso

Objective

To identify the determinants of timely vaccination among young children in the North-West of Burkina Faso.

Methods

This study included 1665 children between 12 and 23 months of age from the Nouna Health and Demographic Surveillance System, born between September 2006 and December 2008. The effect of socio-demographic variables on timely adherence to the complete vaccination schedule was studied in multivariable ordinal logistic regression with 3 distinct endpoints: (i) complete timely adherence, (ii) failure, and (iii) missing vaccination. Three secondary endpoints were timely vaccination with BCG, Penta3, and measles, which were studied with standard multivariable logistic regression.

Results

Mothers’ education, socio-economic status, season of birth, and area of residence were significantly associated with failure of timely adherence to the complete vaccination schedule. Year of birth, ethnicity, and the number of siblings was significantly related to timely vaccination with Penta3 but not with BCG or measles vaccination. Children living in rural areas were more likely to fail timely vaccination with BCG than urban children (OR = 1.79, 95%CI = 1.24–2.58 (proximity to health facility), OR = 3.02, 95%CI = 2.18–4.19 (long distance to health facility)). In contrast, when looking at Penta3 and measles vaccination, children living in rural areas were far less likely to have failed timely vaccinations than urban children. Mother's education positively influenced timely adherence to the vaccination schedule (OR = 1.42, 95%CI 1.06–1.89). There was no effect of household size or the age of the mother.

Conclusions

Additional health facilities and encouragement of women to give birth in these facilities could improve timely vaccination with BCG. Rural children had an advantage over the urban children in timely vaccination, which is probably attributable to outreach vaccination teams amongst other factors. As urban children rely on their mothers’ own initiative to get vaccinated, urban mothers should be encouraged more strongly to get their children vaccinated in time.     

Irregular tick-borne encephalitis vaccination schedules: The effect of a single catch-up vaccination with FSME-IMMUN. A prospective non-interventional study

Background

Intervals longer than recommended are frequently encountered between doses of tick borne encephalitis virus (TBE) vaccines in both residents of and travelers to endemic regions. In clinical practice the management of individuals with lapsed TBE vaccination schedules varies widely and has in common that the underlying immunological evidence is scarce.

Study purpose and methods

The aim of this study was to generate data reliable enough to derive practical recommendations on how to continue vaccination with FSME-IMMUN in subjects with an irregular TBE vaccination history. Antibody response to a single catch-up dose of FSME-IMMUN was assessed in 1115 adults (age ≥16 years) and 125 children (age 6–15 years) with irregular TBE vaccination histories.

Results

Subjects of all age groups developed a substantial increase in geometric mean antibody concentration after a single catch-up TBE vaccination which was consistently lower in subjects with only one previous TBE vaccination compared to subjects with two or more vaccinations. Overall, >94% of young adults and children, and >93% of elderly subjects with an irregular TBE vaccination history achieved antibody levels ≥25 U/ml irrespective of the number of previous TBE vaccinations.

Conclusion

We conclude that TBE vaccination of subjects with irregular vaccination histories should be continued as if the previous vaccinations had been administered in a regular manner, with the stage of the vaccination schedule being determined by the number of previous vaccinations. Although lapsed vaccination schedules may leave subjects temporarily with inadequate protection against TBE infection, adequate protection can quickly be re-established in >93% of the subjects by a single catch-up dose of FSME-IMMUN, irrespective of age, number of previous vaccinations, and time interval since the last vaccination.     

Fewer out-of-sequence vaccinations and reduction of child mortality in Northern Ghana

BackgroundStudies suggest that diphtheria-tetanus-pertussis (DTP) vaccine administered simultaneously with measles vaccine (MV) or DTP administered after MV are associated with higher child mortality than having MV-after-DTP3 as most recent vaccination. We tested this in Northern Ghana where the prevalence of such out-of-sequence vaccinations has declined.MethodsUsing annual cohort data of children aged 12–23 months from 1996 to 2012 and Cox proportional hazards models, we assessed survival in relation to the most recent vaccination status within the next 12 months and until five years of age. We assessed whether mortality in children aged 12–59 months was higher when the most recent vaccine was non-live (DTP) rather than live (MV or OPV).ResultsOut-of-sequence vaccinations with DTP-containing vaccines and MV declined from 86% in 1989 to 24% in 1996 and 0.7% in 2012. Between 1996 and 2012, 38 070 children had their vaccinations status assessed: the adjusted hazard ratio (HR) for out-of-sequence vaccinations (DTP >= MV) compared with the recommended sequence of MV-after-DTP3 was 1.42(1.06–1.90) during the first 12 months after assessment of vaccination status and 1.29(1.03–1.60) with follow-up to five years of age; the HR was 2.58(1.14–5.84) before OPV or MV campaigns and 1.37(1.02–1.85) after the campaigns.ConclusionOut-of-sequence vaccinations with DTP and MV are associated with higher mortality than MV as most recent vaccination; the effect is unlikely to be due to confounding. Hence, the reduction in out-of-sequence vaccinations may have lowered child mortality. It is recommended not to give DTP with MV or DTP after MV.     

Co-administration of live measles and yellow fever vaccines and inactivated pentavalent vaccines is associated with increased mortality compared with measles and yellow fever vaccines only. An observational study from Guinea-Bissau

Background

Studies from low-income countries indicate that co-administration of inactivated diphtheria–tetanus–pertussis (DTP) vaccine and live attenuated measles vaccine (MV) is associated with increased mortality compared with receiving MV only. Pentavalent (DTP–H. Influenza type B–Hepatitis B) vaccine is replacing DTP in many low-income countries and yellow fever vaccine (YF) has been introduced to be given together with MV. Pentavalent and YF vaccines were introduced in Guinea-Bissau in 2008. We investigated whether co-administration of pentavalent vaccine with MV and yellow fever vaccine has similar negative effects.

Methods

In 2007–2011, we conducted a randomised placebo-controlled trial of vitamin A at routine vaccination contacts among children aged 6–23 months in urban and rural Guinea-Bissau. In the present study, we included 2331 children randomised to placebo who received live vaccines only (MV or MV + YF) or a combination of live and inactivated vaccines (MV + DTP or MV + YF + pentavalent). Mortality was compared in Cox proportional hazards models stratified for urban/rural enrolment adjusted for age and unevenly distributed baseline factors.

Results

While DTP was still used 685 children received MV only and 358 MV + DTP; following the change in programme, 940 received MV + YF only and 348 MV + YF + pentavalent. During 6 months of follow-up, the adjusted mortality rate ratio (MRR) for co-administered live and inactivated vaccines compared with live vaccines only was 3.24 (1.20–8.73). For MV + YF + pentavalent compared with MV + YF only, the adjusted MRR was 7.73 (1.79–33.4).

Conclusion

In line with previous studies of DTP, the present results indicate that pentavalent vaccine co-administered with MV and YF is associated with increased mortality.     

Knowledge,attitudes and vaccination coverage of healthcare workers regarding occupational vaccinations

Objectives

Immunization of healthcare workers (HCWs) is a major issue for infection control in healthcare facilities. The aim of this study was to evaluate knowledge regarding occupational vaccinations, HBV, varicella and influenza vaccination rates and attitudes towards influenza vaccine among HCWs.

Design and setting

A cross-sectional survey was conducted in two wards (Medicine and Paediatrics) of a 1182-bed teaching hospital in Paris, France.

Methods

A standardized, anonymous, self-administered questionnaire was used.

Results

Of 580 HCWs, 395 (68%) completed the questionnaire. Knowledge about the occupational vaccinations of HCWs was low. HBV (69%), tuberculosis (54%) and influenza (52%) were the most cited vaccinations. Paediatric staff was more aware of influenza and pertussis immunizations (p < .05). HBV vaccination rate was 93%, among whom 65% were aware of their immune status. Influenza vaccination rate for 2006–2007 was 30% overall, ranging from 50% among physicians to 20% among paramedical staff (p < .05). Physicians based their refusal on doubts about vaccine efficacy, although paramedics feared side effects. Influenza vaccination was associated with knowledge of vaccine recommendations [OR = 1.75, 95% CI: 1.13–2.57] and contact with patients [OR = 3.05, 95% CI: 1.50–5.91].

Conclusions

Knowledge of recommended occupational vaccinations is insufficient in HCWs, except for HBV and influenza. Although the HBV vaccine coverage of HCWs is satisfactory, a large proportion of them is unaware of immune status. Influenza vaccine coverage remains low, especially among paramedical staff because of fear of side effects. As vaccine coverage is associated with knowledge, educational campaigns should be strengthened to increase the adhesion of HCWs to vaccinations.     

Risk factors for low vaccination coverage among Roma children in disadvantaged settlements in Belgrade, Serbia

Background

Full vaccination coverage for children under 59 months of age in Serbia is over 90%. This study assesses vaccination coverage and examines its association with birth registration among Roma children who resided in disadvantaged settlements in Belgrade, Serbia.

Methods

The First Roma Health and Nutrition Survey in Belgrade settlements, 2009, was conducted among households of 468 Roma children between the ages of 6–59 months. The 2005 WHO Immunization Coverage Cluster Survey sampling methodology was employed. Vaccinations were recorded using children's vaccination cards and through verification steps carried out in the Primary Health Care Centers. For those who had health records the information on vaccination was recorded.

Results

About 88% of children had vaccination cards. The mean rate of age appropriate full immunization was 16% for OPV and DTP and 14.3% for MMR. Multivariate analyses indicated that children whose births were registered with the civil authorities were more likely to have their vaccination cards [OR = 6.1, CI (2.5, 15.0)] and to have their full, age appropriate, series vaccinations for DTP, OPV, MMR and HepB [OR = 3.8, CI (1.5, 10.0), OR = 3.2, CI (1.5, 6.6), OR = 4.8, CI (1.1, 21.0), OR = 5.4, CI (1.4, 21.6), respectively].

Conclusions

The immunization coverage among Roma children in settlements is far below the WHO/UNICEF MDG4 target in achieving prevention and control of vaccine preventable diseases. It demonstrates the need to include “invisible” populations into the health systems in continuous, integrated, comprehensive, accessible and sensitive modes.     

No effect of oral polio vaccine administered at birth on mortality and immune response to BCG. A natural experiment

Background

WHO recommends oral polio vaccine at birth (OPV0) in polio endemic countries. During a period without OPV in Guinea-Bissau in 2004, we observed that not receiving OPV0 was associated with significantly decreased mortality in boys and better immune response to BCG vaccination. In 2007, whilst conducting a trial of BCG and vitamin A supplementation (VAS) at birth to low birthweight (LBW) children, OPV was again lacking for a short period. We used this natural experiment to test the previous observations.

Methods

In the trial LBW infants were randomised to early or delayed BCG and VAS or placebo at birth. We noted whether the children received OPV0 or not. We compared children who received No OPV0 with those who received OPV0 in the 2 months before and the 2 months after the period without OPV. Mortality was compared in Cox regression models providing adjusted hazard ratios (aHR); the immune response to BCG was assessed in Poisson models providing adjusted prevalence ratios (aPR).

Results

Ninety-nine children received No OPV0 and were compared with 243 children who received OPV0. No OPV0 was associated with insignificantly higher mortality during the first year of life, the aHR being 1.83 (95% CI: 0.93–3.61). The effect was similar in boys and girls. Overall, there was no significant association between No OPV0 and having a positive PPD response (aPR = 1.33 (0.64–2.78)) or a scar (aPR = 1.02 (0.93–1.11)) after BCG vaccination, though No OPV0 boys were more likely to develop a scar (aPR: 1.10 (1.01–1.20)).

Conclusions

The findings did not support our previous observation that not receiving OPV0 was associated with reduced mortality in boys. The findings weakly supported that OPV0 leads to a dampened response to simultaneously administered BCG vaccine in boys.     

Delaying BCG vaccination from birth to 10 weeks of age may result in an enhanced memory CD4 T cell response

Background

In most tuberculosis (TB) endemic countries, bacillus Calmette–Guérin (BCG) is usually given around birth to prevent severe TB in infants. The neonatal immune system is immature. Our hypothesis was that delaying BCG vaccination from birth to 10 weeks of age would enhance the vaccine-induced immune response.

Methods

In a randomized clinical trial, BCG was administered intradermally either at birth (n = 25) or at 10 weeks of age (n = 21). Ten weeks after vaccination, and at 1 year of age, vaccine-specific CD4 and CD8 T cell responses were measured with a whole blood intracellular cytokine assay.

Results

Infants who received delayed BCG vaccination demonstrated higher frequencies of BCG-specific CD4 T cells, particularly polyfunctional T cells co-expressing IFN-γ, TNF-α and IL-2, and most strikingly at 1 year of age.

Conclusions

Delaying BCG vaccination from birth to 10 weeks of age enhances the quantitative and qualitative BCG-specific T cell response, when measured at 1 year of age.     

Seasonal influenza vaccination trends from 2007–2011 in privately insured children and adults in the United States

Background

To ensure adequate protection from seasonal influenza in the US, the Advisory Committee on Immunization Practices recommends vaccination of all persons aged 6 months or older, with rare exceptions. It also advises starting vaccination as soon as available and continuing throughout the influenza season. This study examined US seasonal vaccination trends during five consecutive influenza seasons in privately-insured children and adults.

Methods

This retrospective, observational cohort study examined trends in influenza vaccination during the 2007–2008 through 2011–2012 influenza seasons using administrative claims data from a large national insurer.

Results

The size of analysis population ranged from 1144,098 to 1245,487 (children, ≥6 months-17 years of age) and from 3931,622 to 4158,223 (adults, 18–64 years of age). Vaccination frequency increased through 2010–2011, was most frequent in young children, and decreased with age. Vaccination rates were highest in the Northeast and lowest in the West and were higher in individuals with frequent outpatient office visits than in those with no or rare visits, with larger differences seen in children. Between 2007 and 2011, the use of preservative-free inactivated vaccine increased, the use of multidose vaccines containing preservatives decreased, and the use of live attenuated influenza vaccines increased among children 2–17 years of age. From 2007–2008 through 2009–2010, the timing of vaccination each year began earlier than the previous one; it remained stable from 2009–2010 through 2011–2012.

Conclusion

Annual influenza vaccination claims for privately-insured children and adults increased and shifted earlier from 2007 through 2009–2011. During the 2011–2012 influenza season, 25.4% of children aged 6 months-17 years and 12.3% of adults aged 18–64 years were vaccinated. Increasing influenza vaccination should remain a priority, and alternative venues for seasonal influenza vaccination should be considered in order to meet the Healthy People 2020 goal of 80% to 90% coverage among children.     

Pertussis vaccination coverage among adults in the Lyon area

Background

The compliance with recommendations for Pertussis vaccination was assessed in the Lyon population through vaccination coverage (VC).

Methods

A cross-sectional study was conducted in collaboration with 10 private biological analysis laboratories between October 2010 and March 2012, on 1930 adults (>19 years of age) from the Lyon area. Proof of vaccination (PV) was requested to prove the current vaccination status.

Results

A percentage of 30.3% (585/1930) of surveyed individuals provided a PV. A positive vaccination status was confirmed in 10.76% [CI 95% 8.45–13.48] (63/585) and didn’t vary in relation to gender (P = 0.57), age (P = 0.06), or level of schooling (P = 0.41). Coverage vaccination was not updated in parents with childbearing project (84.2% (64/76) [CI 95% 74.7–91.2]) or people in contact with children less than 6 years of age (83.6% (87/104) [CI 95% 75.6–89.8]). Pertussis vaccination wasn’t confirmed in 80.0% (124/155) of those who thought being vaccine up to date.

Conclusions

The Lyon population poorly complied with the cocooning strategy implemented in 2004. The pertussis vaccine coverage confirmed by a PV proved the inadequate rate of vaccination compared to objectives. It is mandatory to strengthen the vaccinal policy for this vaccine booster.     

Statut vaccinal des médecins généralistes dans le département de la Loire,France

Objectives

We surveyed the vaccination status of family physicians (FP) in the Loire district (France) in 2010.

Subjects and methods

A self-administered questionnaire was proposed to a panel of 460 FP; 288 (64%) answered.

Results

The vaccination coverage for Diphtheria-Tetanus-Polio in the previous 10 years, BCG, pertussis, seasonal influenza, A/H1N1 2009 influenza, and hepatitis B was 81, 74, 59, 73, 65, and 87% respectively. Sixty-four percent of FP reported they were vaccinated against measles and 49% against chicken pox; 76% were aware of vaccination recommendations for healthcare professionals but 41% wanted more information on the subject. The younger physicians were better vaccinated for Diphtheria-Tetanus-Polio, measles, hepatitis B, and influenza according to a multivariate analysis.

Conclusions

The vaccinations of FP (knowledge, practice) must be improved, especially by yearly updates, continuous medical education, and medical follow-up of healthcare professionals.     

Does oral polio vaccine at birth affect the size of the thymus? Observations within a randomized trial

Background

There is increasing evidence that vaccines have an effect on general mortality which goes beyond specific disease protection. Oral polio vaccine (OPV) is widely used in low-income countries, but in observational studies in Guinea-Bissau we observed that not receiving OPV at birth was associated with reduced overall male infant mortality and enhanced immune response to BCG vaccine. We therefore initiated a randomized trial to test the overall effect of OPV at birth (OPV0).

Objective

A small thymic gland is a predictor of mortality in high-mortality settings. Within the trial we aimed to test whether no-OPV0 was associated with increased thymic size.

Methods

In 511 normal birth weight infants who were randomized to receive or not receive OPV0, thymic index and thymus/weight index were measured before randomization and after 2 weeks (N = 49), 4 weeks (N = 308) or 6 weeks (N = 27). The association between OPV0 and the log transformed thymic size indicators were analyzed in ANCOVA models with thymic size at follow-up as the outcome and adjusting for thymic size at enrollment and age at follow-up. Estimates were reported as geometric mean ratios (GMR) with 95% confidence intervals, comparing no-OPV0 to OPV0.

Results

No-OPV0 was not associated with thymic index after 2 weeks (GMR: 1.14 (0.99–1.30)), after 4 weeks (GMR: 0.98 (0.93–1.05)) or after 6 weeks (GMR: 1.00 (0.81–1.23)). However, no-OPV0 was associated with increased thymus/weight index after 2 weeks (GMR: 1.22 (1.06–1.40)), but the effect was not seen after 4 weeks (GMR: 0.97 (0.92–1.03)) and 6 weeks (GMR: 0.99 (0.82–1.19)). There were no strong sex-differences.

Discussion

Overall there was no effect on thymic size of OPV0 when administered with BCG. The results could indicate that if an effect occurs, it is only within the first weeks after vaccination.     

Maternal determinants of timely vaccination coverage among infants in rural Bangladesh

Background

Timely vaccination, i.e., the receipt of all scheduled vaccinations in an age-appropriate fashion, is critical for the prevention of deadly diseases in infants and achievement of the UN Millennium Development Goal to reduce infant mortality. Infants, especially in rural or underprivileged settings often receive delayed vaccinations leaving them susceptible to vaccine-preventable illnesses early in the first year of life. In this study, we examined rates of timely vaccination among 24,435 infants born in Gaibandha and Rangpur rural districts of Bangladesh from 2001 to 2007.

Methods

Vaccinations due by 14 weeks of age and administered through routine government immunization services were assessed using interviews with enrolled mothers between 11 and 18 weeks postpartum. We created a Timely Vaccination (TV) score to classify infants as vaccinated fully and on schedule (TV = 1) or not (TV = 0), and used multivariable logistic regression to identify maternal characteristics associated with infant's timely vaccination status.

Results

Our results suggest that only 19% of infants in this cohort received scheduled vaccinations on time by 11–18 weeks postpartum. Mothers’ engagement in paid employment [OR = 1.13, 95% CI: 1.03–1.23], receipt of tetanus toxoid vaccination [OR = 1.24, 95% CI: 1.11–1.38], history of antenatal care [OR = 1.22, 95% CI: 1.12–1.32], or higher socioeconomic status [OR = 1.07, 95% CI: 1.03–1.11] were positively associated with timely vaccination of their infants. Mother's perception of small infant size at birth was negatively associated with timely vaccination [OR = 0.89, 95% CI: 0.82–0.97].

Conclusion

Timely vaccination coverage of infants in rural Gaibandha and Rangpur districts is extremely low. This analysis identifies important shortcomings associated with the 1-year vaccination benchmark of routine immunization performance and suggests the need for specific interventions based on potential maternal determinants as well as known system and programmatic barriers of timely vaccination among infants in rural Bangladesh.     

Decline of varicella vaccination in German surveillance regions after recommendation of separate first-dose vaccination for varicella and measles–mumps–rubella

Background

Germany introduced routine varicella (V) vaccination in 2004. Due to a slightly increased risk of febrile convulsions after first-dose application of combined measles–mumps–rubella–varicella (MMRV) vaccine separate first-dose vaccinations with MMR and monovalent V vaccine were recommended in September 2011.

Methods

We compared V and MMR vaccinations in paediatric practices from two surveillance regions (Munich and Würzburg) one year before and after the change in the recommendation.

Results

A total of 1405/326 monthly reports were provided by a monthly average of 79/14 practices participating in Munich/Würzburg. V first-dose vaccinations (monovalent V or MMRV vaccine) declined by 12% in Munich (from 10.1 to 8.9 vaccinations per month and practice; p < 0.005) and by 4% in Würzburg (from 9.9 to 9.5; p = 0.620), respectively. First-dose vaccinations for MMR (MMR or MMRV vaccine) did not change significantly in both regions.

Conclusion

Acceptance of V vaccination depends in part on the use of combination vaccine.     

Universal paid leave increases influenza vaccinations among employees in the U.S.

Objectives

We predict the impact of paid leave in increasing influenza vaccinations for employees, thus decreasing workdays lost and healthcare visits resulting from infection.

Methods

Nationally representative data from the 2006–2010 Medical Expenditure Panel Survey were used. We examined working adults aged 18 and above (N = 51,471). Logistic regression measured the association of paid leave with flu vaccination. We predicted the impact on labor and healthcare markets if universal paid leave were provided.

Results

The proportion of workers receiving vaccination annually was higher for those with paid leave versus without paid leave (34.0% vs. 21.0%, P < 0.001). Adjusted odds of having a vaccination increased with paid leave vs. without paid leave (OR = 1.42, CI: 1.31–1.53). Universal paid leave is predicted to increase vaccinations by 1.6 million, resulting in 63.8 thousand fewer absences from work and 18.2 thousand fewer healthcare visits for the flu annually.

Conclusions

Our study suggests that employees without paid leave are significantly less likely to have had a flu vaccination. Expanding paid leave could substantially increase flu vaccination, resulting in fewer workdays lost to influenza and savings in healthcare costs.     

Antitoxins for diphtheria and tetanus decline more slowly after vaccination with DTwP than with DTaP: A study in a Chinese population

Objectives

DTP vaccines are used for the prevention of pertussis, diphtheria and tetanus. In 2007, in Gaobeidian city, China, the DTwP vaccine was replaced with DTaP. This study described the diphtheria and tetanus sero-epidemiology in subjects vaccinated solely with DTwP or DTaP.

Methods

Blood samples were obtained between October 2012 and June 2013 from 587 healthy subjects aged 2–17 years. Serum IgG antibodies against diphtheria and tetanus were determined using ELISA. Interrupted time series analyses examined the changes in antitoxin levels over time and analyzed the alterations in diphtheria and tetanus antitoxin levels after the vaccine switch.

Results

Mean concentrations of diphtheria antitoxin and tetanus antitoxin were 0.074 IU/ml (95% CI 0.065–0.084) and 0.063 IU/ml (95% CI 0.053–0.076). The protection rates (antitoxins >0.01 IU/ml) for diphtheria and tetanus were 88.25% and 82.11%. Mean antitoxin levels for both diphtheria and tetanus decreased with increasing age, but this decrease was much slower for DTwP than DTaP.

Conclusions

Although the observed protection rates for diphtheria and tetanus were sufficient to prevent an outbreak at present, the means levels of diphtheria and tetanus antitoxins decreased with increasing age; therefore, booster vaccinations at 7 and 12 years of age would be strengthened in Gaobeidian city, China.     

Seasonal influenza vaccine effectiveness in pre- and full-term children aged 6–23 months over multiple seasons

Introduction

This study aimed to determine the effectiveness of seasonal influenza vaccine in pre- and full-term children aged 6–23 months.

Methods

We examined a cohort of 683,354 young children (7.7% preterm) over five influenza seasons (2004–2005 to 2008–2009) in Ontario, Canada. Vaccine effectiveness was estimated using influenza-coded ambulatory visits during virologically-confirmed influenza season periods as the outcome and multivariable Cox proportional hazards modeling.

Results

Full vaccination was associated with a 19% reduction in influenza-coded ambulatory visits (HR = 0.81; 95% CI, 0.68–0.97) in all children, and an 18% reduction in full-term children (HR = 0.82; 95% CI, 0.68–0.99). We did not find significant vaccine effectiveness for preterm children. No benefit was found for partial vaccination.

Conclusions

In children younger than two years, only full influenza vaccination is associated with reduced influenza-coded ambulatory visits. Since the effectiveness of influenza vaccination in preterm children remains uncertain, further study of this highly vulnerable population is warranted.     

Broadening the age restriction for initiating rotavirus vaccination in regions with high rotavirus mortality: Benefits of mortality reduction versus risk of fatal intussusception

Introduction

Recently developed rotavirus vaccines have the potential to reduce diarrhea mortality in children in developing countries. Available data to date do not indicate risk of intussusception with these new vaccines. To avoid a potential unanticipated risk post-licensure, it is recommended that rotavirus immunization be initiated before 12 weeks of age when background intussusception rates are low. This policy could exclude a substantial number of children from vaccination, especially in developing countries where delays in vaccination are common.

Methods

We conducted a scenario analysis to assess the potential benefits of mortality reduction from rotavirus versus the risk of fatal intussusception when the first dose of the vaccine is strictly administered by 12 weeks of age compared with a free strategy with vaccine administered before 1 year of age using data on rotavirus disease, vaccine safety and efficacy, and current diphtheria–tetanus–pertussis vaccination rates, and by incorporating hypothetical risks of intussusception.

Results

In developing countries, assuming vaccine efficacy of 50% and 75% for doses 1 and 2, respectively, and a hypothetical sixfold and threefold increased relative risk of intussusception within 7 days of doses 1 and 2, respectively, initiating rotavirus immunization before 12 weeks of age would prevent 194,564 of the 517,959 annual rotavirus-associated deaths among children <5 years, while potentially resulting in 1106 fatal intussusception events. Administration of the first dose to infants up to 1 year of age would prevent an additional 54,087 rotavirus-associated deaths (total = 248,651) while potentially resulting in an additional 1226 intussusception deaths (total = 2332).

Conclusion

In developing countries, the additional lives saved by broadening the age restrictions for initiation of rotavirus vaccination would far outnumber the hypothetical excess intussusception deaths that would accompany such an approach.