Measles–mumps–rubella vaccination and respiratory syncytial virus-associated hospital contact

BackgroundThe live measles vaccine has been associated with lower non-measles mortality and admissions in low-income countries. The live measles–mumps–rubella vaccine has also been associated with lower rate of admissions with any type of infection in Danish children; the association was strongest for admissions with lower respiratory infections.ObjectiveTo examine whether measles, mumps, and rubella (MMR) vaccination was associated with reduced rate of hospital contact related to respiratory syncytial virus (RSV) in a high-income country.MethodsNationwide cohort study of laboratory-confirmed RSV hospital contacts at age 14–23 months in all children born in Denmark 1997–2002 who had already received the vaccine against diphtheria, tetanus, pertussis (acellular), polio, and Haemophilus influenzae type b (DTaP-IPV-Hib) at the recommended ages of 3, 5, and 12 months.ResultsThe study included 888 RSV hospital contacts in 128,588 person years of follow up (rate 6.8/1000 person years). Having MMR as the most recent vaccine was associated with a reduced rate of RSV hospital contacts compared with having DTaP-IPV-Hib as the most recent vaccine (Incidence rate ratio (IRR), 0.75; 95% confidence interval (CI), 0.63–0.89). After adjustment for potential confounders including exact age in days the IRR was 0.78 (95% CI, 0.66–0.93). The adjusted IRR was 0.74 (95% CI, 0.60–0.92) in males and 0.84 (95% CI, 0.66–1.06) in females (P Interaction, 0.42). There was no association in the first month after MMR vaccination (adjusted IRR, 0.97; 95% CI, 0.76–1.24) but the adjusted IRR was 0.70 (95% CI, 0.58–0.85) from one month after MMR vaccination.ConclusionsMMR vaccination was associated with reduced rate of hospital contacts related to laboratory-confirmed RSV infection. Further research on the association between MMR vaccination and other unrelated pathogens are warranted.     

A retrospective nationwide register-based study to evaluate the non-specific effects of first MMR vaccination among children in Finland

BackgroundAccording to earlier studies, live vaccines like measles-mumps-rubella (MMR) vaccine could reduce also other infections than only the infections they are targeted against. This non-specific effect has been seen especially in studies in low-income countries and results from high-income countries have not been unambiguous. In 2011 Finland changed the recommended schedule for the first MMR vaccination from 18 months to 12 months of age. This change created a natural experiment for evaluating the potential non-specific effects.MethodsThis is a retrospective nationwide register-based cohort study of Finnish children born between 2008 and 2012. Children were divided into two cohorts by age at MMR vaccination: children administered early MMR vaccination (11 through 12 months of age) and late MMR vaccination (18 through 19 months of age). Morbidity was evaluated during the main follow-up period (from 13 to 17 months of age) and before any MMR vaccination (3 to 10 months) and after all were vaccinated with MMR (20 to 35 months) as control follow-up periods. We analyzed all infections and did additional analyzes for urinary tract infections (UTI) and bronchitis. Injuries were analyzed as a control outcome.ResultsEarly MMR vaccinated children (N = 79 949) had fewer infections compared to late MMR vaccinated (N = 60 965) during the main follow-up period. The incidence rate ratio (IRR) was 0.84 (95 % confidence interval (95 % CI) 0.81–0.87). However, similar differences were also observed during the control follow-up periods. MMR vaccinated children had less UTI in the main follow-up period (IRR 0.73, 0.60–0.89) but not in the control follow-up periods. When stratified by sex, the difference was observed among girls but not in boys.ConclusionNo clear evidence was found for non-specific effects in infectious diseases morbidity. However, there could be a nonspecific effect on UTI. Confirmation is needed from other studies, especially from high-income countries.     

No evidence of an increase of bacterial and viral infections following Measles,Mumps and Rubella vaccine

The suggestion that multi-antigen vaccines might overload the immune system has led to calls for single antigen vaccines. In 2003 we showed that rather than an increase there appeared to be a reduced risk of severe bacterial infection in the three months following Measles, Mumps and Rubella vaccine (MMR). The present analysis of illnesses in a general population is based on an additional 10 years of data for bacterial infections and also includes admissions with viral infections. Analyses were carried out using the self-controlled case-series method and separately for bacterial and viral infection cases, using risk periods of 0–30 days, 31–60 days and 61–90 days post MMR vaccine. An analysis was also carried out for those cases which were given MMR and Meningococcal serogroup C (MCC) vaccines concomitantly.A reduced risk was seen in the 0–30-day period for both bacterial infection (relative incidence = 0.68, 95% CI 0.54–0.86) and viral infections (relative incidence = 0.68, 95% CI 0.49–0.93). There was no increased risk in any period when looking at combined viral or bacterial infections or for individual infections with the single exception of an increased risk in the 31–60 days post vaccination period for herpes infections (relative incidence = 1.69, 95% CI 1.06–2.70). For the children given Meningococcal group C vaccines concomitantly no significantly increased risk was seen in either the bacterial (relative incidence = 0.54, 95% CI 0.26–1.13) or viral cases (relative incidence = 0.46, 95% CI 0.11–1.93).Our study confirms that the MMR vaccine does not increase the risk of invasive bacterial or viral infection in the 90 days after the vaccination and does not support the hypothesis that there is an induced immune deficiency due to overload from multi-antigen vaccines.     

Pneumococcal vaccination in patients with systemic lupus erythematosus: A multicenter placebo-controlled randomized double-blind study

BackgroundInvasive pneumococcal disease and respiratory tract infections are both frequent and severe in patients with systemic lupus erythematosus (SLE). This study aimed to compare the immunological efficacy and safety of pneumococcal vaccination with the 23-valent polysaccharide (PPS) vaccine alone to a sequential immunization with the 7-valent pneumococcal conjugate (PnCj) vaccine followed by PPS in patients with SLE and stable diseaase.MethodsMulticenter randomized placebo-controlled double-blind trial: PPS vaccine alone (placebo-PPS group) or PnCj vaccine followed by PPS vaccine (PnCj-PPS group) 24 weeks later. The primary endpoint was the rate of responders at week 28 to at least 5 of the 7 serotypes (4, 6B, 9V, 14, 18C, 19F and 23F) shared by both PPS and PnCj. Pneumococcal IgG antibodies’ opsonophagocytic activity (OPA) were also assessed.ResultsTwenty-five patients in the placebo-PPS group and 17 in the PnCj-PPS group were included in a modified intention-to-treat analysis. The primary endpoint was reached in 72% (18/25) in the placebo-PPS and 76% (13/17) in the PnCj-PPS group (p = 0.75). There was no difference in the rates of responders with OPA. At week 52, 13/18 (72%) patients in the placebo-PPS group and 10/13 (77%) patients in the PnCj-PPS group (p = 0.77) that met the primary endpoint at week 28 were still responders to ≥5/7 serotypes shared by both PPS and PnCj vaccines. Nine SLE flares were reported in 6 patients (4 in the placebo-PPS and 2 in the PnCj-PPS groups respectively, p = 0.70).ConclusionSequential administration of PnCj vaccine followed by PPS vaccine is safe and shows short-term immunological efficacy in patients with SLE but was not superior to the PPS vaccine alone.Trial registration: www.clinicaltrials.gov, NCT NCT00611663     

Correlates of HPV vaccine uptake in school-based routine vaccination of preadolescent girls in Norway: A register-based study of 90,000 girls and their parents

ObjectiveTo assess demographic, socioeconomic and behavioural correlates of HPV vaccination of preadolescent girls in a publicly funded, school-based vaccination programme.MethodsData for all Norwegian girls born 1997–1999, eligible for routine school-based HPV vaccination in 2009–2011 (n = 90,842), and their registered mother and father, were merged from national registries. Correlates of girl vaccination status were analysed by unadjusted and multivariable logistic regression.ResultsIn total, 78.2% of the girls received the first dose of the HPV vaccine, 74.6% received three doses, and 94.8% received the MMR vaccine. Correlates associated with initiation of HPV vaccination included parental age, income and education, maternal occupational status and cervical screening attendance, and girl receipt of the MMR vaccine. Rates of completion of HPV vaccination among initiators were high, and disparities in completion were negligible. Maternal and paternal correlates of daughter HPV vaccination status were similar.ConclusionsRoutine school-based vaccination generally provides equitable delivery, yet some disparities exist. Information campaigns designed to reach the sub-groups with relatively low vaccine uptake could reduce disparities. In none of the sub-groups investigated did uptake of the HPV vaccine approach that of the MMR vaccine, further demonstrating a general potential for improvement in HPV vaccine uptake.     

Safety of quadrivalent live attenuated influenza vaccine in subjects aged 2–49 years

BackgroundQuadrivalent live attenuated influenza vaccine (Q/LAIV) was licensed in 2012 and replaced trivalent live attenuated influenza vaccine in the United States during the 2013–2014 influenza season. This study assessed the safety of Q/LAIV in children and adults aged 2–49 years.MethodsThis was a prospective observational cohort study using data collected from Kaiser Permanente Northern California. Post-vaccination events of interest were any hospitalization, hospitalization for lower respiratory tract infection, and the following medically attended events: hypersensitivity, seizures/convulsions, lower respiratory tract infection, wheezing, Guillain-Barré syndrome, Bell’s palsy, encephalitis, neuritis, vasculitis, and narcolepsy/cataplexy. The rates of these events during the risk interval post-vaccination were compared with rates observed during reference periods later in the follow-up (within-cohort analysis) and with rates observed in frequency-matched unvaccinated controls and inactivated influenza vaccine (IIV) recipients.ResultsA total of 62,040 eligible Q/LAIV recipients were identified during the 2013–2014 influenza season. Within-cohort comparisons of all Q/LAIV recipients as well as comparisons between Q/LAIV recipients and unvaccinated controls or IIV recipients did not show any significantly higher risk of hospitalizations or medically attended events following administration of Q/LAIV. Additional analyses by setting (clinic visits, emergency department visits, and hospital admissions) and age group (2–4, 5–8, 9–17, and 18–49 years) also did not reveal clinically consistent findings that suggested any increased risk after administration of Q/LAIV.ConclusionIn this large population study of individuals aged 2–49 years, no safety signals associated with the administration of Q/LAIV were observed. A much larger study population would be needed to confidently reject any association between Q/LAIV and very rare events, specifically those with an incidence of <1 event/10,000 person-years.Trial registration: ClinicalTrials.gov NCT01985997     

Immunogenicity and safety of concomitant MF59-adjuvanted influenza vaccine and 23-valent pneumococcal polysaccharide vaccine administration in older adults

BackgroundConcomitant administration of influenza and pneumococcal vaccines facilitates their uptake by older adults; however, data on immunogenicity and safety of concomitant administration of adjuvanted trivalent inactivated influenza vaccine (aIIV3) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) have not been reported.MethodsSubjects aged ≥65 years (N = 224) were randomized 1:1:1:1 to receive MF59-aIIV3 alone, MF59-aIIV3 + PPSV23 in contralateral arms, MF59-aIIV3 + PPSV23 in the same arm or PPSV23 alone (Clinical Trial Number – NCT02225327). Hemagglutination inhibition assay and multiplex opsonophagocytic killing assay were used to compare immunogenicity after single or concomitant vaccination.ResultsAll groups met immunogenicity criteria for the influenza vaccine in older adults with similar seroconversion rates and geometric mean fold-increases, irrespective of concomitant vaccinations and injection site. For each pneumococcal serotype, opsonic index (OI) increased markedly after the PPSV23 vaccination, irrespective of the concomitant influenza vaccine. All subjects showed an OI ≥ 8 for serotypes 6B, 18C and 19A post-vaccination, with a suggestion that the ipsilateral concomitant vaccination might be associated with higher OIs for some antigens. Local and systemic adverse events were more common in subjects receiving PPSV23 compared to those receiving aIIV3 alone.ConclusionsNo interference was observed with antibody responses to influenza or pneumococcal antigens when aIIV3 and PPSV23 were administered concomitantly.     

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine and an MF59-adjuvanted influenza vaccine after concomitant vaccination in ⩾60-year-old adults

BackgroundConcomitant administration of influenza and pneumococcal vaccines could be an efficient strategy to increase vaccine uptake among older adults. Nevertheless, immune interference and safety issues have been a concern when more than one vaccines are administered at the same time.MethodsSubjects aged ⩾60 years were randomized in a 1:1:1 ratio to receive MF59-adjuvanted trivalent inactivated influenza vaccine (MF59-aTIV) + 13-valent pneumococcal conjugate vaccine (PCV13) (Group 1), PCV13 alone (Group 2), or MF59-aTIV alone (Group 3). Hemagglutination inhibition (HI) and opsonophagocytic activity (OPA) assays were used to compare immunogenicity after single or concomitant vaccination.ResultsA total of 1149 subjects (Group 1, N = 373; Group 2, N = 394; Group 3, N = 382) were available for the assessment of immunogenicity and safety. All groups met immunogenicity criteria for the influenza vaccine in older adults with similar seroprotection rates, seroconversion rates, and geometric mean titer (GMT) fold-increases, irrespective of concomitant vaccination. For each pneumococcal serotype, OPA titers increased markedly after the PCV13 vaccination, irrespective of the concomitant influenza vaccination. After concomitant administration, the non-inferiority criteria of GMT ratios were met for all three influenza subtypes and 13 pneumococcal serotypes. No vaccine-related serious adverse events occurred.ConclusionsConcomitant MF59-aTIV and PCV13 administration showed no interference with antibody response and showed good safety profiles.(Clinical Trial Number – NCT02215863).     

Impact of vaccination on influenza mortality in children <5 years old in Mexico

BackgroundInfluenza is a leading cause of respiratory tract infections among children. In Mexico, influenza vaccination was included in the National Immunization Program since 2004. However, the population health effects of the vaccine on children have not been fully described. Thus, we estimated the impact of influenza immunization in terms of mortality associated with this virus among children younger than 5 years of age in Mexico.MethodsMortality rates and years of life lost associated with influenza were estimated using national mortality register data for the period 1998–2012. Age-stratified and cause-specific mortality rates were estimated for all-cause, respiratory and cardiovascular events. Influenza-associated mortality was compared between the period prior to introduction of the influenza vaccine as part of the National Immunization Program (1998–2004) and the period thereafter (2004–2012).ResultsDuring the 1998–2012 winter seasons, the average number of all-cause, respiratory and cardiovascular deaths attributable to influenza were 1186, 794 and 21, respectively. Influenza-associated mortality was higher prior to the vaccination period than after influenza was included in the immunization program for all-cause (mean 1660 vs. 780) and respiratory (mean 1063 vs. 563) mortality, but no reduction was seen for cardiovascular mortality. The proportion of all-cause and respiratory deaths attributable to influenza was significantly lower in the post-vaccine period compared with the pre-vaccine period (P < 0.001), but no reduction was seen in the proportion of cardiovascular deaths. There was an average annual reduction of 66,558 years of life lost in the post-vaccine compared with the pre-vaccine period.ConclusionThe introduction of influenza vaccination within the Mexican Immunization Program was associated with a reduction in mortality rates attributable to this virus among children younger than 5 years of age.     

Influence of information sources on vaccine hesitancy and practices

IntroductionMany factors influence vaccination practices and attitudes. This study aimed to identify vaccine information sources used by parents of children aged 1–15 years to get a better understanding of the relation between vaccine information sources, practices for two vaccines (MMR, HBV), vaccine acceptance, and vaccine hesitancy.MethodsA total of 3938 parents, drawn by random sampling, were interviewed by telephone as part of the “2016 health barometer” survey. Vaccine information sources were described and analyzed according to socio-demographic variables. Multivariate logistic regression models were then built to explain vaccine information sources usage, vaccination practices and attitudes.ResultsHealthcare professionals (HCP), the Internet, and relatives were the three main vaccine information sources. Vaccination practices and acceptance were better when parents were getting information from HCPs compared with parents getting information from the Internet or relatives. Besides, getting information from the three different types of sources was associated with the highest rate of vaccine hesitancy: 70.9% (OR = 4.6; P < 0.0001) versus 34.6% among parents getting information from HCPs only.ConclusionThose results suggest an interest in providing quality information about vaccination on the Internet. The primary role of HCPs in vaccination decision is once again demonstrated.     

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.     

Lower vaccine uptake amongst older individuals living alone: A systematic review and meta-analysis of social determinants of vaccine uptake

IntroductionVaccination is a key intervention to reduce infectious disease mortality and morbidity amongst older individuals. Identifying social factors for vaccine uptake enables targeted interventions to reduce health inequalities.ObjectiveTo systematically appraise and quantify social factors associated with vaccine uptake amongst individuals aged ≥60 years from Europe.MethodsWe searched Medline and Embase from inception to 24/02/2016. The association of vaccine uptake was examined for social factors relevant at an individual level, to provide insight into individuals’ environment and enable development of targeted interventions by healthcare providers to deliver equitable healthcare. Factors included: living alone, marital status, education, income, vaccination costs, area-level deprivation, social class, urban versus rural residence, immigration status and religion. Between-study heterogeneity for each factor was identified using I²-statistics and Q-statistics, and investigated by stratification and meta-regression analysis. Meta-analysis was conducted, when appropriate, using fixed- or random-effects models.ResultsFrom 11,754 titles, 35 eligible studies were identified (uptake of: seasonal influenza vaccine (SIV) only (n = 27) or including pneumococcal vaccine (PV) (n = 5); herpes zoster vaccine (n = 1); pandemic influenza vaccine (n = 1); PV only (n = 1)). Higher SIV uptake was reported for individuals not living alone (summary odds ratios (OR) = 1.39 (95% confidence interval (CI): 1.16–1.68). Lower SIV uptake was observed in immigrants and in more deprived areas: summary OR = 0.57 (95%CI: 0.47–0.68) and risk ratio = 0.93 (95%CI: 0.92–0.94) respectively. Higher SIV uptake was associated with higher income (OR = 1.26 (95%CI: 1.08–1.47)) and higher education (OR = 1.05 (95%CI: 1–1.11)) in adequately adjusted studies. Between-study heterogeneity did not appear to result from variation in categorisation of social factors, but for education was partly explained by varying vaccination costs (meta-regression analysis p = <0.0001); individuals with higher education had higher vaccine uptake in countries without free vaccination.ConclusionsQuantification of associations between social factors and lower vaccine uptake, and notably living alone (an overlooked factor in vaccination programmes), should enable health professionals target specific social groups to tackle vaccine-related inequalities.     

A randomized trial of the effect of vaccine injection speed on acute pain in infants

ObjectiveThis study compared the pain caused from fast vs. slow vaccine injections.MethodsInfants aged 2–6 months receiving primary immunizations were randomized to fast (2–4 mL/s) or slow (5–10 mL/s) injections during routine 0.5 mL Diphtheria, Tetanus, acellular Pertussis, Inactivated Polio Virus, Haemophilus influenzae type b vaccine (DTaP-IPV-Hib) injections. Those aged 2 and 4 months additionally received 0.5 mL Pneumococcal Conjugate Vaccine (PCV) injections. A research assistant and parent unaware of treatment allocation and hypothesis assessed pain using validated and recommended tools, including; the Modified Behavioural Pain Scale (MBPS, range 0–10), cry duration, and Numerical Rating Scale (NRS, range 0–10). The primary outcome was infant pain score using the MBPS.ResultsAltogether, 120 were recruited; 61 were randomized to fast injections and 59 to slow injections. One hundred and ninteen infants participated. There were no differences in characteristics, including; age (p = 0.994) and sex (p = 0.540). The mean MPBS score (standard deviation) during DTaP-IPV-Hib injection was lower in the fast injection group: 6.4 (2.7) vs. 7.4 (2.5), respectively; p = 0.046. Regression analysis demonstrated a positive correlation between injection speed and pain. There were no other differences between groups.ConclusionFast injection reduced injection-induced pain in infants receiving DTaP-IPV-Hib but not PCV vaccine. Fast injections are recommended when administering vaccines because of the potential for a reduction in pain, feasibility and practicality.Trial registration: NCT02504398     

Contrasting female-male mortality ratios after routine vaccinations with pentavalent vaccine versus measles and yellow fever vaccine. A cohort study from urban Guinea-Bissau

BackgroundIn addition to protection against the target diseases, vaccines may have non-specific effects (NSEs). Measles vaccine (MV) has beneficial NSEs, providing protection against non-measles deaths, most so for girls. By contrast, though protecting against diphtheria, tetanus and pertussis, DTP vaccine is associated with increased female mortality relative to male mortality. In 2008, Guinea-Bissau replaced DTP with the DTP-containing pentavalent vaccine (Penta; DTP-H. influenza type B-Hepatitis B) at 6, 10 and 14 weeks and yellow fever vaccine (YF) was to be given with MV. We investigated possible sex-differential mortality rates following Penta and MV+YF vaccination.MethodsBandim Health Project (BHP) registers vaccines given by the three government health centres in the study area and vital status through demographic surveillance. We assessed the association between sex and mortality by vaccination status in Cox proportional hazards models with age as underlying timescale. Follow-up was censored at a subsequent vaccination contact or after 6 months of follow-up.ResultsBetween September 2008 and April 2011, we registered 23,448 vaccination contacts for children aged 42–365 days; 17,313 were for Penta and 3028 for MV (2907 co-administered with YF). During follow-up 112 children died. The female/male mortality rate ratio was 1.73 (1.11–2.70) following Penta and 0.38 (0.12–1.19) after MV (p = 0.02 for same effect). Adjusting for maternal education or weight-for-age at the time of vaccination did not change the estimates.ConclusionPenta appears to have the same negative effects on mortality as those seen for DTP. Assessing post-vaccination mortality for boys and girls is necessary to improve the vaccination programme.     

Travel medicine consultation: An opportunity to improve coverage for routine vaccinations

BackgroundTravelers may be responsible for the spread of vaccine-preventable diseases upon return. Travel physicians and family physicians may play a role in checking and updating vaccinations before traveling. Our aim was to evaluate the vaccine coverage for mandatory and recommended vaccination in travelers attending a travel medicine clinic (TMC).MethodsVaccine coverage was measured using the current French immunization schedule as reference for correct immunization, in travelers providing a vaccination certificate during the TMC visit (university hospital of Saint-Étienne), between August 1, 2013 and July 31, 2014.ResultsIn total, 2336 travelers came to the TMC during the study period. Among the 2019 study participants, only 1216 (60.3%) provided a vaccination certificate. Travelers who provided a vaccination certificate were significantly younger than travelers who did not (mean age: 34.8 ± 17.8 vs. 46 ± 18.4 years, P < 0.005) and were less likely to be Hajj pilgrims. Vaccine coverage against Tetanus, Diphtheria, and Poliomyelitis (Td/IPV vaccine) was 91.8%, 78.6% against Measles, Mumps, and Rubella (MMR), and 59.4% against Viral Hepatitis B (HBV). BCG vaccine coverage was 71.9%. Older travelers were less likely to be correctly vaccinated, except against HBV as vaccinated travelers were significantly older than unvaccinated travelers.ConclusionObtaining information about immunization in travelers is difficult. Coverage for routine vaccines should be improved in this population. Travel medicine consultations could be the opportunity to vaccinate against MMR, HBV, and Td/IPV.     

Evaluation of potentially achievable vaccination coverage with simultaneous administration of vaccines among children in the United States

BackgroundRoutine administration of all age-appropriate doses of vaccines during the same visit is recommended for children by the National Vaccine Advisory Committee (NVAC) and the Advisory Committee on Immunization Practices (ACIP).MethodsEvaluate the potentially achievable vaccination coverage for ≥4 doses of diphtheria and tetanus toxoids and acellular pertussis vaccine (4+DTaP), ≥4 doses of pneumococcal conjugate vaccine (4+PCV), and the full series of Haemophilus influenzae type b vaccine (Hib-FS) with simultaneous administration of all recommended childhood vaccines. Compare the potentially achievable vaccination coverage to the reported vaccination coverage for calendar years 2001 through 2013; by state in the United States and by selected socio-demographic factors in 2013. The potentially achievable vaccination coverage was defined as the coverage possible for the recommended 4+DTaP, 4+PCV, and Hib-FS if missed opportunities for simultaneous administration of all age-appropriate doses of vaccines for children had been eliminated.ResultsCompared to the reported vaccination coverage, the potentially achievable vaccination coverage for 4+DTaP, 4+PCV, and Hib-FS could have increased significantly (P < 0.001), the vaccination coverage would have achieved the 90% target of Healthy People 2020 for the three vaccines beginning in 2005, 2008, and 2011 respectively. In 2013, the potentially achievable vaccination coverage increased significantly across all selected socio-demographic factors, potentially achievable vaccination coverage would have reached the 90% target for more than 51% of the states in the United States.ConclusionsThe findings in this study suggest that fully utilization of all opportunities for simultaneous administration of all age-eligible childhood doses of vaccines during the same vaccination visit is a critical strategy for achieving the vaccination coverage target of Healthy People 2020. Encouraging providers to deliver all recommended vaccines that are due at each visit by implementing client reminder and recall systems might decrease missed opportunities for simultaneous administration of childhood vaccines.     

Febrile seizures following measles and varicella vaccines in young children in Australia

BackgroundFebrile seizures (FS) are common in childhood with incidence peaking in the second year of life when measles and varicella-containing vaccines are administered. This study aimed to examine the vaccine-attributable risk of FS following separate administration of MMR and monovalent varicella vaccines (VV) prior to a planned change to MMRV as the second dose of measles-containing vaccine at 18 months of age.MethodsAll FS cases in children aged <5 years from 1st January 2012 to 30th April 2013 were identified from emergency department (ED) and inpatient databases at five Australian tertiary paediatric hospitals participating in PAEDS (Paediatric Active Enhanced Disease Surveillance). Immunization records were obtained from the Australian Childhood Immunization Register (ACIR). The relative incidence (RI) of FS following MMR dose 1 (MMR1) and VV in children aged 11–23 months was determined using the self-controlled case series (SCCS) method and used to calculate attributable risk.ResultsThere were 2013 FS episodes in 1761 children. The peak age at FS was 18 months. The risk of FS was significantly increased 5–12 days post receipt of MMR1 at 12 months (RI = 1.9 [95% CI: 1.3–2.9]), but not after VV at 18 months (RI = 0.6 [95% CI: 0.3–1.2]. The estimated excess annual number of FS post MMR1 was 24 per 100,000 vaccinated children aged 11–23 months (95% CI = 7–49 cases per 100,000) or 1 per 4167 doses.ConclusionsOur study detected the expected increased FS risk post MMR1 vaccine at 12 months, but monovalent varicella vaccine at age 18 months was not associated with increased risk of FS. This provides baseline data to assess the risk of FS post MMRV, introduced in Australia as the second dose of measles-containing vaccine at 18 months of age in July 2013.     

Vaccination with a live multi-gene deletion strain protects horses against virulent challenge with Streptococcus equi

Strangles, caused by Streptococcus equi subspecies equi (S. equi) is one of the most frequently diagnosed infectious diseases of horses and there remains a significant need to develop new preventative vaccines. We generated a live vaccine strain of S. equi containing deletions in six genes: sagA, hasA, aroB, pyrC, seM and recA, which was administered to nine Welsh mountain ponies via the intramuscular route. Four vaccinated ponies developed adverse reactions following the first vaccination from which the live vaccine strain was isolated. Two of these ponies were withdrawn from the study and seven ponies received a second vaccination, one of which then developed an adverse reaction. Nine control ponies injected with culture media alone developed no adverse reactions. Following challenge with a virulent strain of S. equi, none of the seven vaccinated ponies had developed clinical signs of strangles eleven days post-challenge, compared to six of nine control ponies over the same period (P = 0.0114). A lymph node abscess was identified in one of the seven vaccinated ponies at post-mortem examination, whilst all nine control ponies had at least one lymph node abscess (P = 0.0009). Three of the six vaccinated ponies that were protected from strangles had not developed an adverse reaction following vaccination, suggesting that a better understanding of the pro-inflammatory responses to S. equi could lead to the development of a live attenuated vaccine against strangles that is safe for administration via intramuscular injection.     

Chronically ill adolescents are also incompletely vaccinated: A cross-sectional study in France

BackgroundAdolescent vaccination coverage tends to be suboptimal, leading to resurgent infectious pathologies and vulnerability to various pathogens. The low frequency of medical consultations and missed opportunities for vaccination are often used to explain the low rate of vaccination. The aim of this study was to assess if the vaccination coverage rate is higher in chronically ill adolescents (CIA) who require a close pediatric specialized follow-up versus the rate in healthy adolescents (HA).MethodsA monocentric cross-sectional study was conducted in the Nantes University Hospital. We included 114 CIA and 266 HA. The vaccination coverage rate and the up-to-date immunization status were compared between ill versus healthy adolescents for each of the following vaccines: diphtheria, tetanus, acellular pertussis, inactivated poliovirus (DTaP/IPV), measles-mumps-rubella (MMR), hepatitis B (HepB), meningococcal C conjugate (MnC), human papillomavirus (HPV) and composite combinations (e.g. DTaP/IPV-MMR-HepB-MnC).ResultsThe overall immunization rate for DTaP/IPV-MMR-HepB-MnC was very low, with no significant difference between CIA and HA (9.6% versus 13.5%; p = 0.28). Most of the investigated vaccines exhibited similar immunization patterns for the two groups: DTaP/IPV (77.2 vs. 76.7%; p = 0.97), MMR (92.1 vs. 95.9%; p = 0.14), HepB (51.8 vs. 48.5%; p = 0.51) with the exception of the MnC (18.4 vs. 27.8%; p = 0.05) and HPV (28.6 vs. 16.1%; p = 0.04).ConclusionDespite undergoing specialized and close medical follow-up, we found that the vaccination coverage rate for the CIA remained suboptimal. This indicates that pediatricians need to check the vaccination status and, when required, ensure that the vaccination schedules for these fragile patients are up-to-date.     

Birth outcomes for Australian mother-infant pairs who received an influenza vaccine during pregnancy, 2012–2014: The FluMum study

IntroductionIn Australia, influenza vaccination is recommended for all women who will be pregnant during the influenza season. Vaccine safety and effectiveness are key concerns and influencers of uptake for both vaccine providers and families. We assessed the safety of receiving an influenza vaccination during any trimester of pregnancy with respect to preterm births and infant birthweight.MethodsWe conducted a nested retrospective cohort study of ‘FluMum’ participants (2012–2014). Our primary exposure of interest was influenza vaccination during pregnancy. The primary outcomes of interest were infant birthweight and weeks’ gestation at birth for live singleton infants. Analyses included comparisons of these birth outcomes by vaccination status and trimester of pregnancy an influenza vaccine was given. We calculated means, proportions, and relative risks and performed multivariable logistic regression for potential confounding factors.ResultsIn the 7126 mother-infant pairs enrolled in this study, mean maternal age at infant birth was 31.7 years. Influenza vaccine uptake in pregnancy was 34%. Most mothers with a known date of vaccination received a vaccine in the second trimester (51%). Those mothers with a co-morbidity or risk factor were 13% more likely to have influenza vaccine during pregnancy compared to other mothers (RR 1.13, 95% CI 1.04–1.24, p = 0.007). Mean weeks’ gestation at birth was 38.7 for the vaccinated and 38.8 for the unvaccinated group (p = 0.051). Infants in the vaccinated group weighed 15 g less in birthweight compared to the unvaccinated infants (95% CI −12.8 to 42.2, p = 0.29).ConclusionResults arising from this large Australian cohort study are reassuring with respect to two critical safety outcomes; preterm births and low infant birthweights. Studies examining a broader range of birth outcomes following influenza vaccination during pregnancy are required, particularly now that maternal vaccination in pregnancy has expanded to include pertussis as well as influenza.