Seizures in children with fever: Generally good outcome

Hexavalent vaccines in infants: a systematic literature review and meta-analysis of the solicited local and systemic adverse reactions of two hexavalent vaccines

Introduction: The hexavalent vaccine DT3aP-HBV-IPV-Hib (Infanrix hexa, GSK) was first licensed in Europe in 2000. DT2aP-HBV-IPV-Hib (Hexyon/Hexacima/Hexaxim, Sanofi Pasteur), and DT5aP-HBV-IPV-Hib (Vaxelis, MCM Vaccine Company) were licensed in the EU in 2013 and 2016, respectively, based largely on studies demonstrating non-inferiority to DT3aP-HBV-IPV-Hib for immunogenicity and comparable reactogenicity profiles.Methods: We conducted a systematic literature review looking for direct head-to-head trials comparing DT2aP-HBV-IPV-Hib and DT5aP-HBV-IPV-Hib with DT3aP-HBV-IPV-Hib. The incidence of solicited local and systemic reactions following primary series administration of DT3aP-HBV-IPV-Hib or DT2aP-HBV-IPV-Hib were meta-analyzed.Results: A total of 317 unique records were retrieved from the search; nine met the predefined inclusion criteria; seven reported studies comparing DT3aP-HBV-IPV-Hib and DT2aP-HBV-IPV-Hib. Six trials assessing outcomes of the primary vaccination series were identified. Odds ratios and 95% confidence intervals (OR; 95%CI) were computed for DT3aP-HBV-IPV-Hib, using DT2aP-HBV-IPV-Hib as reference, for redness (0.72; 0.63-0.83), pain (0.74; 0.62-0.89), swelling (0.86; 0.74-0.99) at injection site, fever (0.67; 0.54-0.83), persistent crying (0.72; 0.61-0.84), drowsiness (0.82; 0.71-0.94), irritability (0.82; 0.69-0.98), anorexia (0.83; 0.72-0.95), and vomiting (0.96; 0.83-1.11).Conclusion: ORs of analyzed local and systemic solicited adverse reactions after primary vaccination with DT3aP-HBV-IPV-Hib appear to be slightly lower than with DT2aP-HBV-IPV-Hib.

Combination Measles-Mumps-Rubella-Varicella Vaccine in Healthy Children: A Systematic Review and Meta-analysis of Immunogenicity and Safety

A combined measles-mumps-rubella-varicella (MMRV) vaccine is expected to facilitate universal immunization against these 4 diseases. This study was undertaken to synthesize current research findings of the immunogenicity and safety of MMRV in healthy children.We searched PubMed, Embase, BIOSIS Previews, Web of Science, Cochrane Library, and other databases through September 9, 2014. Eligible randomized controlled trials (RCTs) were selected and collected independently by 2 reviewers. Meta-analysis was conducted using Stata 12.0 and RevMan 5.3.Twenty-four RCTs were included in qualitative synthesis. Nineteen RCTs compared single MMRV dose with measles-mumps-rubella vaccine with or without varicella vaccine (MMR + V/MMR). Similar seroconversion rates of these 4 viruses were found between comparison groups. There were comparable geometric mean titers (GMTs) against mumps and varicella viruses between MMRV group and MMR + V/MMR group. MMRV group achieved enhanced immune response to measles component, with GMT ratio of 1.66 (95% confidence interval [CI] 1.48, 1.86; P < 0.001) for MMRV versus MMR and 1.62 (95% CI 1.51, 1.70; P < 0.001) for MMRV versus MMR + V. Meanwhile, immune response to rubella component in MMRV group was slightly reduced, GMT ratios were 0.81 (95% CI 0.78, 0.85; P < 0.001) and 0.79 (95% CI 0.76, 0.83; P < 0.001), respectively. Well tolerated safety profiles were demonstrated except higher incidence of fever (relative risks 1.12-1.60) and measles/rubella-like rash (relative risks 1.44-1.45) in MMRV groups.MMRV had comparable immunogenicity and overall safety profiles to MMR + V/MMR in healthy children based on current evidence.

Risk of febrile seizure after measles-mumps-rubella-varicella vaccine: A systematic review and meta-analysis

BACKGROUND

Considering the febrile seizure rate, there is no longer a clear preference for use of measles-mumps-rubella-varicella (MMRV) vaccine over separate measles-mumps-rubella (MMR) and varicella (V) vaccine. This work was undertaken to assess the risk of febrile seizure after MMRV vaccine in children.

METHODS

We searched PubMed, Embase, BIOSIS Previews, Scopus, Web of Science, Cochrane Library and other databases through 12 December 2014. Meta-analysis was conducted using R version 3.1.2 and Stata version 12.0.

RESULTS

A total of thirty-nine studies were included. Thirty-one published or unpublished clinical trials involving about 40,000 subjects did not show significant differences in incidence of febrile seizure or vaccine related febrile seizure between MMRV and MMR with or without varicella vaccine after any doses, in the risk windows of 0-28, 0-42 or 0-56 days and 7-10 days. In addition, these studies showed that the receipt of concomitant use of MMRV and other pediatric vaccines was not a significant predictor of febrile seizure. Eight post-marketing observations involving more than 3,200,000 subjects were included. No evidence suggested elevated risk of febrile seizure associated with MMRV vaccine among children aged 4-6 years old during 7-10 days or 0-42 days after vaccination. However, an approximately 2-fold increase in risk of seizure or febrile seizure during 7-10 days or 5-12 days after MMRV vaccination was found among children aged 10-24 months, although the highest incidence of seizure was still lower than 2.95‰.

CONCLUSIONS

First MMRV vaccine dose in children aged 10-24 months was associated with an elevated risk of seizure or febrile seizure. Further post-marketing restudies based on more rigorous study design are needed to confirm the findings.

The safety and immunogenicity of a quadrivalent measles, mumps, rubella and varicella vaccine in healthy children: a study of manufacturing consistency and persistence of antibody

BACKGROUND

This clinical trial was conducted to demonstrate that each of 3 consistency lots of a combined measles, mumps, rubella and varicella vaccine (MMRV) would be well tolerated, induce clinically acceptable and similar immune responses to each antigen and induce immune responses similar to measles, mumps and rubella vaccine (MMR) administered concomitantly with varicella vaccine (V). An additional objective was to evaluate the persistence of antibodies 1 year postvaccination.

METHODS

Study participants 12 to 23 months of age received a single injection of either one of 3 consistency lots of MMRV or MMR + V administered at separate injection sites.

RESULTS

A total of 3,928 healthy children were enrolled at study sites in the United States and Canada. Immune responses to measles, mumps, rubella and varicella in children immunized with each of 3 lots of MMRV were similar and the combined response to all 3 lots was comparable to that of the control group. The 1-year antibody persistence rates for measles, mumps, rubella and varicella viruses were each greater than 95% and comparable among the recipients of the 3 consistency lots of MMRV and the control group. All vaccines were generally well tolerated during the 42 days after vaccination and the overall incidence of adverse experiences was comparable between recipients of MMRV and MMR + V. Rates of fever (temperature >or=38.9 degrees C oral equivalent or tactile) were greater in recipients of MMRV than in recipients of MMR + V (39.1% versus 33.1%, P = 0.001). Fevers were transient and there was no difference in the incidence of febrile seizures.

CONCLUSIONS

MMRV was generally well tolerated and had comparable immunogenicity and overall safety profiles to MMR + V administered concomitantly. Long-term persistence of antibodies after receipt of MMRV is expected based on similar antibody titers against all 4 antigens 1 year postvaccination compared with recipients of MMR and V.