Adverse effects and sero-responses to an acellular pertussis/diphtheria/tetanus vaccine when combined with Haemophilus influenzae type b vaccine in an accelerated schedule

Comparison of adverse events following immunisation with acellular and whole-cell pertussis vaccines: A systematic review

INTRODUCTION

Two types of vaccines are currently licensed for use against pertussis: whole-cell (wP) and acellular pertussis (aP). There is evidence that wP confers more durable immunity than aP, however wP has been more frequently associated with adverse events following immunisation (AEFI). A comparison of the frequency of AEFI with the first doses of wP and aP has not yet been clearly documented. This must be done in light of recent considerations to move towards a wP prime-aP boost vaccination strategy in low and middle-income countries.

OBJECTIVES

To compare the frequency of AEFI associated with the first dose of the wP and aP vaccines. We also compared the frequency of AEFI associated with subsequent doses of wP.

METHODS

This systematic review was carried out in strict accordance with the published protocol.

RESULTS

High heterogeneity amongst included one-armed studies did not allow for pooling of prevalence estimates. The prevalence estimates of AEFI at first vaccine dose of wP ranged from 0 to 75%, while the prevalence estimates of AEFI at first vaccine dose of aP ranges from 0 to 39%. The prevalence estimates of adverse events following second and third vaccine dose of wP ranged from 0 to 71% and 0 to 61%, respectively. Risk ratios among two-armed studies showed an increased risk of adverse events with first dose of wP compared to aP [local reaction RR 2.73 (2.33, 3.21), injection site pain RR 4.15 (3.24, 5.31), injection site swelling RR 4.38 (2.70, 7.12), fever over 38 °C RR 9.21 (5.39, 15.76), drowsiness RR 1.34 (1.18, 1.52) and vomiting RR 1.28 (0.91, 1.79)].

CONCLUSION

Our results confirm that, when comparing the first dose, wP is more reacotgenic than aP. The proposed wP prime followed by aP boost pertussis vaccine strategy should be approached with caution.

Seroprevalence and placental transmission of maternal antibodies specific for Neisseria meningitidis Serogroups A, C, Y and W135 and influence of maternal antibodies on the immune response to a primary course of MenACWY-CRM vaccine in the United Kingdom

BACKGROUND

Maternal antibodies give neonates some protection against bacterial infection. We measured antibodies against Neisseria meningitidis serogroups A, C, Y and W135 in mothers and their 2-month-old infants at study enrollment. We also assessed the impact of maternal antibody present at 2 months of age on the immune response to a primary course of quadrivalent meningococcal conjugate vaccine (MenACWY-CRM197) given at 2 and 4 months of age.

METHODS

This was a single-center, open-label, randomized study undertaken in Oxford, United Kingdom. Two hundred sixteen healthy infants were enrolled in the study and vaccinated with MenACWY-CRM197 at 2 and 4 months of age. Blood was obtained from all mothers, in a subset of infants at 2 months and all infants at 5 months. Antibody and memory B-cell responses at 5 months were correlated with maternal antibodies.

RESULTS

Mothers had low IgG antibodies against serogroups C, W135 and Y polysaccharides, but high serogroup A antibody, whereas 61-78% had protective human complement serum bactericidal activity (hSBA) (≥1:4) for serogroups C, W135 and Y but only 31% for serogroup A. Only 9%, 32%, 45% and 19% of 2-month-old infants had hSBA ≥1:4 for serogroups A, C, W135 and Y, respectively. Maternal antibody had little association on responses to MenACWY-CRM197, except a moderate negative association between MenC-specific bactericidal antibody at 2 and 5 months (r = -0.5, P = 0.006, n = 28) and between carrier-specific IgG antibody at 2 months and MenC-specific hSBA/IgG antibody at 5 months (r = -0.4, P = 0.02 and 0.04, n = 32 and 23). Nonetheless, 90% of infants achieved protective MenC-hSBA titers after vaccination at 2 and 4 months of age.

CONCLUSIONS

The levels of serogroup-specific meningococcal antibodies were low in mothers and 2-month-old infants. Immunizing mothers before or during pregnancy with meningococcal conjugate vaccines might increase antibody levels in early infancy and provide protection against infection due to N. meningitidis.

A local reaction at or near injection site: case definition and guidelines for collection, analysis, and presentation of immunization safety data

The need for developing a case definition and guidelines for a local reaction at or near the injection site, methods for the development of the case definition and guidelines as an adverse event following immunization as well as the rationale for selected decisions about the case definition for a local reaction at or near the injection site are explained in the Preamble section. The case definition is structured in 2 levels of diagnostic certainty: level 1 includes any description of morphological or physiological change at or near the injection site that is described or identified by a healthcare provider. Level 2 is any description of morphological or physiological change at or near injection site that is described by any other person. In Guidelines section, the working group recommends to enable meaningful and standardized data collection, analysis, and presentation of information about a local reaction at or near the injection site. However, implementation of all guidelines might not be possible in all settings. The availability of information may vary depending upon resources, geographic region, and whether the source of information is a prospectively designed clinical trial, a post-marketing surveillance or epidemiologic study, or an individual report of a local reaction at injection site.

Breastfeeding attenuates reductions in energy intake induced by a mild immunologic stimulus represented by DPTH immunization: possible roles of interleukin-1beta, tumor necrosis factor-alpha and leptin

An attenuated severity of infections is among the well-documented benefits of breast-feeding. The degree to which this attenuated severity extends to the amelioration of anorexia is understood incompletely, and possible underlying mechanisms have received limited evaluation. This study was designed to test whether breast-feeding attenuates reductions in energy intake associated with a mild immunologic stimulus and to assess poststimulus relationships among putative reductions in energy intake and serum interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and leptin concentrations. A quasi-experimental, hospital-based study was conducted in 23 healthy fully breast- (BF) and formula-fed (FF) infants who received the quadruple diphtheria, pertussis, tetanus and hemophilus influenza (DPTH) immunization as an immunologic challenge. Only FF infants had decreased energy intakes (12 +/- 2%, P = 0.001) after immunization. Leptin concentrations increased after immunization only in FF infants (30 +/- 7%, P = 0.03). Correlations between postimmunization increases in IL-beta and reductions in energy intake were of borderline significance (r = -0.56, P = 0.08). These findings support the view that breast-feeding protects against anorectic responses to mild immunologic stimuli. Increases in leptin are associated with reductions in energy consumption in the postimmunization period in FF infants and postimmunization changes in IL-1beta concentrations likely are related to reductions in energy intake in response to immunologic stimuli.

Immunity to Bordetella pertussis

Bordetella pertussis exploits extracellular and intracellular niches in the respiratory tract and a variety of immune evasion strategies to prolong its survival in the host. This article reviews evidence of complementary roles for cellular and humoral immunity in protection. It discusses the effector mechanisms of bacterial elimination, the strategies employed by the bacteria to subvert protective immune responses and the immunological basis for systemic and neurological responses to infection and vaccination.