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There was no association between antibody titres and infection episodes after two vaccine doses, but antibody titres were associated with lower BTI risk after three or four vaccine doses on multivariable analysis. B Conclusion: b Anti-S antibody titres can predict the risk of COVID-19 infection after three or more vaccine doses in patients with lymphoma. B Introduction: b Patients with B-cell lymphoma have poorer antibody responses to COVID-19 vaccines compared to patients with other malignancies. [Extracted from the article]

The incidence of tuberculosis (TB) in native ethnic minorities remains high in developed countries. Arabs, the major ethnic minority in Israel, comprise 21% of its population. This retrospective study compared TB incidence, demographic, clinical, laboratory, genotyping characteristics and treatment outcomes in all Israeli-born citizens diagnosed with TB between 1999 and 2011 by ethnicity, i.e. Israeli-born Arabs (IA) and Jews (IJ). A total of 831 Israeli-born TB patients were reported. Of those, there were 530 (64%) IJ and 301 (36%) IA, with an average annual TB rate of 1·1 and 1·6 cases/100 000 population, respectively, lower than the national average (7·0 cases/100 000 population). TB rates in IA and IJ declined and converged to 1 case/100 000 residents. IA TB patients were more likely to be older, have more pulmonary TB and have lower treatment success rates than IJ. Older age and HIV co-infection, but not ethnicity, were predictive of non-success in TB treatment. Ten mixed IA–IJ clades were detected by spoligotyping and three mixed IA–IJ clusters were identified by MIRU-VNTR typing. Only one IA–IJ couple recalled mutual contact. In conclusion, TB rate in IA was higher than in IJ, but declined and converged in both to 1 case/100 000. Treatment success was high in both groups, and was unrelated to ethnicity. [ABSTRACT FROM PUBLISHER]

Antiretroviral therapy (ART) only partially restores HIV-induced alterations in lymphocyte populations. We assessed B and T cell phenotypes in a cohort of children from a single centre in the United Kingdom with perinatally acquired HIV compared to healthy controls. The majority of HIV infected children (44 of 56) were on fully suppressive combination ART. Children with perinatally acquired HIV had significantly lower memory B and CD4+CD45RO+CXCR5+ [follicular T helper cell (Tfh)-like] T cell percentages. Detectable viraemia was associated with higher CD21- (activated and exhausted/tissue-like memory) B cells. A greater proportion of life spent on suppressive ART was associated with higher memory B cell percentages. These results suggest that early and sustained suppressive ART may preserve B and T cell phenotypes in perinatally acquired HIV and limit deficits in humoral immunity. A lower proportion of circulating Tfh-like cells in HIV infected children appears to be independent of HIV treatment history and ongoing HIV viraemia and warrants further investigation. [ABSTRACT FROM AUTHOR]

Chronic Granulomatous Disease (CGD) is a rare primary immunodeficiency due to a defect in one of the NADPH oxidase complex subunits; 70 % of cases are X-linked, due to a CYBB mutation, resulting in defective production of gp91 PHOX. Female carriers of X-linked CGD have previously been considered to be unaffected. It is increasingly recognized that they may suffer from similar problems to CGD patients. This review will examine the literature about clinical manifestations of disease in X-linked carriers of CGD. [ABSTRACT FROM AUTHOR]

There are no epidemiological studies from the British Isles of chronic granulomatous disease, characterized by recurrent, life-threatening bacterial and fungal infections and inflammatory sequelae. Patients were enrolled in a national registry and medical records were analysed. Of 94 subjects, 69 had X-linked disease, 16 had autosomal recessive disease and nine were unknown. Prevalence was 7·5/million for 1990–99 and 8·5/million for 1980–89. Suppurative adenitis, abscesses and pneumonia presented commonly. Twenty-three of 30 patients who underwent high resolution computerized tomography had chronic respiratory disease. Inflammatory sequelae included bowel stricture and urogenital tract granulomata. Growth failure was common; 75% of those measured were below the population mean. All patients received prophylactic antibiotics and 93% anti-fungal prophylaxis. Interferon gamma was used to treat infection, but rarely as prophylaxis. Despite prophylaxis, estimated survival was 88% at 10 years but 55% at age 30 years. Morbidity remains significant, severe infectious complications common. Curative treatments including stem cell transplantation should be considered for patients with frequent or serious complications. [ABSTRACT FROM AUTHOR]

The molecular and functional characteristics of natural antibody from the preimmune repertoire have not been explored in detail in man. We describe seven human IgM monoclonal antibodies selected on the basis of pneumococcal polysaccharide binding that share both molecular and functional characteristics with natural antibody, suggesting a common B cell lineage origin. Unlike class-switched antibodies, which are serotype-specific, the antibodies were polyreactive and bound all pneumococcal polysaccharide capsular serotypes tested. Some bound endogenous antigens, including blood group antigens and intermediate filament proteins. All the antibodies used unmutated heavy chain V (IGHV) that are expressed at an increased frequency in the elderly and in the preimmune repertoire. The CDR3 was characterized by long length (mean aa 18·4 (±4·2) and selective use of IGHD6 ( P < 0·001) and IGHJ6 ( P < 0·01) family genes. The clones expressing IGHV1-69 and IGHV 3-21 provided significant passive protection against invasive pneumococcal disease in vivo. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the utility of anti-nuclear antibody (ANA) testing in the investigation of cutaneous and other lupus symptoms in female carriers of X-linked chronic granulomatous disease (CGD). We undertook a prospective study of 19 carrier mothers attending our institution, with direct questioning of carriers concerning symptoms and testing for anti-nuclear and anti-phospholipid antibodies. A total of 58% reported significant photosensitive skin rashes, 42% reported mouth ulcers and 37% complained of joint pains that could not be attributed to other known causes. Anti-nuclear antibody (ANA) testing was negative in 73% of all carriers. The five positive ANAs were of low titre (maximum 1 : 320 on Hep 2 cells in two women) and only one weak positive double-stranded DNA antibody and no extractable nuclear antibodies were found. Several of the mothers, despite negative serology, benefited from referral to a specialist, and in some cases to specific treatment. A history of skin rashes, joint pain, fatigue and mouth ulcers should be sought actively in the female relatives of X-CGD patients but negative lupus serology should not preclude referral to appropriate dermatology or rheumatology services. as symptoms may respond well to appropriate treatment. [ABSTRACT FROM AUTHOR]

We investigated the nasopharyngeal carriage of Streptococcus pneumoniae and Staphylococcus aureus in 355 children hospitalized with severe pneumonia. Of the children, 239 (67.3%) were human immunodeficiency virus (HIV)-1 positive; 169 (47.6%) carried S. pneumoniae, 91 (25.6%) carried S. aureus, and 33 (9.3%) carried both. S. pneumoniae carriage was not related to HIV-1 status. The HIV-1-positive children had a significantly higher rate of S. aureus carriage than did the HIV-1-negative children (31.4% vs. 13.8%; P<.001). The rate of S. aureus carriage in the HIV-1-negative S. pneumoniae carriers was significantly lower than that in the noncarriers (5.5% vs. 21.3%; P=.013), but the rate of S. aureus carriage in the HIV-1-positive S. pneumoniae carriers was not significantly lower than that in the noncarriers (26.3% vs. 36.0%; P=.11). We did not find a negative association between S. pneumoniae and S. aureus carriage in HIV-1-positive hospitalized children with severe pneumonia. Copyright © 2006 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

Aim: To test the efficacy of T-cell-dependent and T-cell-independent vaccines in rural Gambian children suffering from a range of energy/protein and micronutrient deficiencies.Methods: Nutritional status (anthropometry, haemoglobin, plasma leptin and micronutrient status) and response to two vaccinations (23 valent pneumococcal capsular polysaccharide vaccine, Pneumovax and the Human Diploid-Cell Rabies Vaccine) were assessed in 472 children aged 6 1/2 h to 9 1/2 y.Results: Anthropometry and micronutrient status (as z-scores against European reference values) indicated a range from moderate to severe levels of undernutrition [mean (interquartile range): weight-for-age z-score -1.58 (-2.18 to -0.95); height-for-age z-score -0.94 (-1.51 to -0.35); body-mass-index-for-age z-score -1.43 (-2.05 to -0.84); mid-upper arm circumference -1.41 (-1.72 to -1.13); leptin -1.06 (-1.10 to -1.03); haemoglobin (Hb) -0.30 (-1.18 to 0.79); zinc -1.29 (-2.42 to -0.55); vitamin C -0.01 (-1.18 to 1.15); retinol -1.33 (-1.97 to -0.77)]. A seasonal effect was observed in haemoglobin levels and in all micronutrients (with the exception of zinc and retinol) and in the response to vaccination. After adjusting for seasonality, age and gender, no consistent associations were found between any of the measures of nutritional status and the effectiveness of seroconversion to either of the vaccines.Conclusion: The successful short-term seroconversion to whole inactivated viral and bacterial polysaccharide vaccines indicates that the processes leading to antibody secretion remain intact over a wide range of single and combined nutrient deficiencies. [ABSTRACT FROM AUTHOR]

Aim: To assess whether a fourth Hib polysaccharide-tetanus protein conjugate vaccine (PRP-T) would improve antibody response in preterm infants previously treated with dexamethasone for chronic lung disease. Methods: In a pilot study 12 infants born at less than 30 weeks gestation who had received corticosteroids were given a supplementary Hib dose six weeks after completion of the primary immunisation course. Serum samples obtained before and at eight weeks following the fourth Hib dose were analysed for total level and avidity of anti-PRP antibody. Results: There was no significant increase in the geometric mean titre (GMT) of anti-PRP antibody resulting from the fourth Hib immunisation (GMT: pre 2.35 µg/ml, post 2.24 µg/ml, p = 0.79). A subgroup of six infants had subprotective antibody levels (<1.0 µg/ml) after the primary immunisation course, which remained subprotective following the extra Hib immunisation. Despite the poor response in total antibody level, the study group showed a significant rise in PRP specific IgG avidity following the fourth immunisation (GMAI: pre 0.076, post 0.138, p = 0.043). Conclusion: An additional Hib immunisation given to recently steroid treated preterm infants six weeks after completion of the primary schedule did not augment primary immunogenicity. However, increasing avidity may imply successful priming and long term immunity to Hib. [ABSTRACT FROM AUTHOR]

Background and Objectives Intravenous immunoglobulin (WIG) is used in a range of immunodeficiency states that require a broad spectrum of protective antibodies to a range of common pathogens. A comparison of the antigen-specific antibody profile of preparations of an IVIG (Vigam®) derived from US and UK sourced plasma was performed, and these preparations were also compared with three other WIG products from different manufacturers. Materials and Methods Antibodies against a range of bacterial and viral pathogens were measured by immunoassay. Results Similar profiles were found for Vigam® made from UK and US source plasma and also for the other three WIGs tested, but some specific differences were observed. Conclusions WIG preparations have a similar therapeutic spectrum of antibodies when prepared from plasma sourced either from the UK or the US. [ABSTRACT FROM AUTHOR]

SUMMARY Hyper IgE syndrome (HIES) is a rare immunodeficiency disorder characterized mainly by high levels of polyclonal IgE in serum and recurrent staphylococcal abscesses of the skin and lungs. The raised IgE levels have led researchers to study the synthesis of cytokines that regulate switching of immunoglobulin production towards IgE such as interleukin-4 (IL-4), IL-12 and interferon-γ (IFN)-γ. However, the role of IL-13 in the disease pathogenesis has not been investigated extensively. In this study, we investigated intracellular expression of IL-4 and IL-13 in mononuclear cells and CD4+ cells isolated from patients with HIES and healthy controls. Cells were stained intracellularly with antibodies directed against IL-4 and IL-13 and analysed by flow cytometry before and after activation with PMA and calcium ionophore. The mean proportion of resting or activated IL-4 and IL-13 expressing mononuclear cells were comparable in the two groups as well as the proportion of IL-4 expressing CD4+ cells. In contrast, the mean proportion of IL-13 expressing CD4+ cells was increased significantly in patients with HIES in both the resting and the activated state compared to healthy controls. We conclude that increased expression of IL-13 in CD4+ cells from patients with HIES could account, at least partly, for raised IgE levels in those individuals. [ABSTRACT FROM AUTHOR]

SUMMARY Dendritic cells (DCs) were derived from human peripheral blood monocytes or cord blood monocytes cultured in the presence of IL-4 and GM-CSF. Adult and cord DCs were observed to have comparable immature phenotypes. However, the increase in surface expression of HLA-DR and CD86 after addition of LPS was significantly attenuated in cord DCs, with CD25 and CD83 expression also markedly reduced. Cord DCs were also unable to produce IL-12p70, failed to down-regulate expression of the chemokine receptor CCR5 and induced lower levels of IFN-γ production from allogeneic naive CD4+ T cells than their adult counterparts. In contrast, the kinetics of the production of TNF-α and IL-10 in response to LPS stimulation was comparable to adult DCs. The reduced ability of cord DCs to attain a fully mature adult phenotype, and to activate naive CD4+ T cells to produce IFN-γ, suggests that they are intrinsically preprogrammed against the generation of Th-1 immune responses. [ABSTRACT FROM AUTHOR]

Common variable immunodeficiency (CVID) is the most frequently occurring primary immunodeficiency in both children and adults. The molecular basis of CVID has not been defined, and diagnosis involves exclusion of other molecularly defined disorders. X-linked lymphoproliferative disease (XLP) is a rare disorder in which severe immunodysregulatory phenomena typically follow Epstein–Barr virus (EBV) infection. Boys who survive initial EBV infection have a high incidence of severe complications, including progressive immunodeficiency, aplastic anaemia, lymphoproliferative disease and lymphoma. Survival beyond the second decade is unusual, although bone marrow transplantation can be curative. Until recently reliable diagnostic testing for XLP has not been available, but the identification of the XLP gene, known as SH2D1A, and coding for a protein known as SAP, means that molecular diagnosis is now possible, both by protein expression assays, and mutation detection, although the mutation detection rate in several series is only 55–60%. We describe three male patients initially diagnosed as affected by CVID, one of whom developed fatal complications suggestive of XLP, and all of whom lack expression of SAP. Two out of three have disease-causing mutations in the SAP gene, consistent with published data for XLP. These findings raise the possibility that a subgroup of patients with CVID may be phenotypic variants of XLP. Further studies are necessary to investigate this possibility, and also to clarify the prognostic significance of SAP abnormalities in such patients in the absence of typical features of XLP. [ABSTRACT FROM AUTHOR]

To test for immunologic memory after a single dose of meningococcal C conjugate (MCC) vaccine in toddlers, 226 children 12-18 months old were randomized to receive 1 of 3 MCC vaccines, with a C polysaccharide booster 6 months later. The protein conjugate was diphtheria mutant toxoid in 2 vaccines (MCC-CRM(197)) and was tetanus toxoid in the third (MCC-TT). One month after the MCC vaccines, 91%-100% of children had serum bactericidal antibody (SBA) titers > or =8, and 89%-100% had a > or =4-fold increase. Geometric mean titer (GMT) increased from <4 to 215 (95% confidence interval [CI], 166-279). MCC-TT induced higher SBA GMTs (P<.001) and higher proportions with SBA > or =8 (P=.02) than did the MCC-CRM(197) vaccines. By 6 months, GMTs had decreased to 55.1 (95% CI, 40-76), but IgG antibody avidity increased (P<.001). Induction of immunologic memory was confirmed by a GMT of 1977 (range, 1535-2547) after the polysaccharide booster and a further increase in avidity. This evidence justified the use of a single dose in a catch-up immunization program for children 1-18 years old. [ABSTRACT FROM AUTHOR]

Characterizes hypergammaglobulinaemia and chronic granulomatous infiltration caused by Staphylococcus aureus, Proteus or Pseudomonas. Impact of respiratory burst during phagocytosis on oxidative metabolism; Inhibitors of mitochondrial respiration; Mechanism of glucose oxidation via hexose monophosphate shunt.

Outcomes for children with chronic granulomatous disease (CGD) have historically been poor, but significant improvements have occurred with the use of effective antibacterial prophylaxis. The present study aimed to document the clinical course of a cohort of children diagnosed with CGD since 1990 in a single centre. Twenty-one patients were identified, with a median age at last assessment of 4 years and 5 months. A third of these children were diagnosed in infancy because of a positive family history. Of the remaining, there was a median delay between the onset of symptoms and diagnosis of 13 months. No invasive or fungal infections were documented after diagnosis, nor were there any deaths in this cohort. A variety of non-infectious complications were noted, which responded well to steroids. As a group, these children were thriving and weight and height distributions fell within the population norm. All patients were receiving antibacterial prophylaxis, 90% with co-trimoxazole, and all but one patient were receiving a prophylactic anti-fungal agent (itraconazole). Both drugs were well tolerated. In conclusion, this cohort of patients, diagnosed in the last decade, tolerated antibacterial and anti-fungal prophylaxis well and on this regimen have a significantly decreased incidence of infection when compared with historical cohorts. Careful follow up of patients who have had aggressive antibacterial and anti-fungal prophylaxis should continue. The data reported on this cohort of patients should inform the debate about the use of more aggressive treatments, such as bone marrow transplantation, in this disease. [ABSTRACT FROM AUTHOR]

Although antibody affinity is primarily determined by immunoglobulin variable region structure human IgG antibodies of the four subclasses specific for the same antigen have been shown to differ in their affinity. To explore the influence of the immunoglobulin constant region on functional antibody affinity, a set of V region identical mouse-human chimeric IgG subclasses specific for TAG72 (tumour-associated glycoprotein) were studied. Biomolecular interaction analysis (BIA) was used to determine the binding kinetics of whole IgG subclasses and F(ab′)2 fragments. Despite identical V regions, binding kinetics differed for the four subclasses. The apparent dissociation rate constants of the intact immunoglobulins ranked IgG4 < IgG3 < IgG2 < IgGl. In contrast, analysis of the binding characteriztics of the F(ab′)2 fragments derived from IgG1, IgG2 and IgG4 revealed identical binding kinetics. The structure of the constant regions of the humanized IgG subclass antibodies clearly influenced functional antibody affinity, as has been described for the murine IgG subclasses. The exact mechanism for this phenomenon remains obscure but such differences should be taken into account when designing or choosing antibodies for therapeutic use. [ABSTRACT FROM AUTHOR]

Evaluation of the new generation of conjugate vaccines is hampered by the absence of reliable surrogate markers of immunologic memory. Memory responses are characterized by rapid production of relatively high-avidity antibody; thus, a solid-phase ELISA was adapted for the measurement of anti-Haemophilus influenzae type b (Hib) IgG avidity. In a cohort of infants vaccinated at 2, 3, and 4 months of age with Hib conjugate vaccines, avidity increased in the period following vaccination, while antibody titer fell. After a booster dose at 1 year of age, both antibody titer and avidity increased. In a cohort with anti-Hib IgG <1.0 µg/mL following primary immunization, antibody avidity after booster was low, indicating an absence of priming. Antibody avidity may help distinguish, in persons with low antibody titers, between those who are primed for memory and those who are not. [ABSTRACT FROM PUBLISHER]

Objective: To describe the immune response of preterm infants, with a reduced response to primary Hoemophilus influenzae type B (Hib) immunisation, to a Fourth dose of Hib conjugate vaccine given in early life. Design: Prospective observational study. Setting: Five Wessex Neonatal Units. Patients: Infants born at < 32 weeks and immunised with three doses of combined acellular pertussis-Hib vaccine, with a Hib IgG geometric mean concentration (GMC) < 1.0 μg/ml after, these primary immunisations. Interventions: An additional fourth dose of Hib conjugate vaccine given before 1 year of age. Blood taken to assess Hib IgG concentration and avidity alter immunisation. Main outcome measures: Hib IgG GMC and avidity index. Results: Ninety six infants (mean gestational age at birth 29.1 weeks) received a fourth dose of Hib at a mean age of 7.8 months. Hib IgG GMC after the primary immunisations was 0.17 μg/ml (95% confidence interval (Cl) 0.14 to 0.20) rising to 4.68 μg/ml (95% Cl 3.36 to 6.57) after the fourth dose (p < 0.0001). The IgG response to the fourth dose correlated positively with the response after the primary immunisations (p < 0.001). Hib IgG geometric mean avidity index (GMAI) after the primary immunisations was 30.87 (95% Cl 20.40 to 46.73). This increased to 124.73 (95% Cl 109.93 to 141.51) after the fourth dose (p < 0.0001). Conclusion: Preterm infants with very low IgG responses to Hib after primary immunisations with a combined acellular pertussis-Hib vaccine mount a good response to a fourth dose of Hib. This study suggests that all infants wilt benefit from a fourth dose of Hib, regardless of the age at which it is given. [ABSTRACT FROM AUTHOR]

Focuses on the efficacy of conjugate vaccines. Reduction of Haemophilus influenzae type b; Immunology of the vaccines; Correlation between antibody levels and vaccine immunogenicity.

Objective: To investigate the immunogenicity of Haemophilus influenzae type b (Hib) conjugate vaccines in children with sickle cell disease.Design: Open study.Setting: Haemoglobinopathy clinic.Subjects: Children with homozygous haemoglobin SS disease (HbSS), sickle haemoglobin C disease (HbSC), and sickle-beta thalassaemia disease (HbS-beta Thal).Interventions: Children over the age of 2 years received a single dose of Hib-tetanus toxoid conjugate vaccine (PRP-T).Main Outcome Measures: Antibody response to Hib polysaccharide (PRP) approximately one month after vaccination.Results: 77 children over the age of 2 years were studied,, 55 with HbSS, 16 with HbSC, and six with HbS-beta Thal. Before vaccination, 44% had anti-PRP IgG titres less than the level associated with long term protection (1.0 microgram/ml). After a single dose of PRP-T all children mounted an antibody titre > 1 microgram/ml. Geometric mean anti-PRP IgG titre achieved postvaccination (45.2 micrograms/ml 95% confidence interval (CI) 31.6 to 64.8) was comparable to that of a healthy population. Children with HbSC, however, had a significantly higher antibody titre postvaccination (91.1 micrograms/ml; 95% CI 32.7 to 254.4) than the children with HbSS (36.7 micrograms/ml; 95% CI 25.1 to 52.9).Conclusions: Children with a diagnosis of sickle cell disease who are over the age of 2 years make a vigorous antibody response to a single dose of PRP-T vaccine and hence we suggest unimmunised individuals in this group should receive a single dose of a Hib conjugate vaccine. [ABSTRACT FROM AUTHOR]

Aim: To assess whether a fourth Hib polysaccharide-tetanus protein conjugate vaccine (PRP-T) would improve antibody response in preterm infants previously treated with dexamethasone for chronic lung disease.Methods: In a pilot study 12 infants born at less than 30 weeks gestation who had received corticosteroids were given a supplementary Hib dose six weeks after completion of the primary immunisation course. Serum samples obtained before and at eight weeks following the fourth Hib dose were analysed for total level and avidity of anti-PRP antibody.Results: There was no significant increase in the geometric mean titre (GMT) of anti-PRP antibody resulting from the fourth Hib immunisation (GMT: pre 2.35 micro g/ml, post 2.24 micro g/ml, p = 0.79). A subgroup of six infants had subprotective antibody levels (<1.0 micro g/ml) after the primary immunisation course, which remained subprotective following the extra Hib immunisation. Despite the poor response in total antibody level, the study group showed a significant rise in PRP specific IgG avidity following the fourth immunisation (GMAI: pre 0.076, post 0.138, p = 0.043).Conclusion: An additional Hib immunisation given to recently steroid treated preterm infants six weeks after completion of the primary schedule did not augment primary immunogenicity. However, increasing avidity may imply successful priming and long term immunity to Hib. [ABSTRACT FROM AUTHOR]

Reports that the rates of invasive diseases in the developed world, has been reduced, due to the immunization of infants with conjugate vaccines. Considerations by the World Health Organization (WHO); Reference to the administered booster dose of the conjugate vaccine in the second year of life; In-depth look at the immunization of infants with conjugate vaccines.

Presents a letter to the editor on the efficacy of a diphtheria/tetanus/acellular pertussis-Haemophilus influenzae type b vaccine.

The article describes the immune response of preterm infants, with a reduced response to primary Haemophilus influenzae type B (Hib) immunization, to a forth dose of Hib conjugate vaccine given in early life. The study concludes that preterm infants with very low IgG responses to Hib after primary immunizations with a combined acellular pertussis-Hib vaccine mount a good response to a fourth dose of Hib. This study also suggests that all infants will benefit from a fourth dose of Hib, regardless of the age at which it is given.

Corrects wrongly labeled diagrams of the article 'Increased expression of interleukin-13 but not interleukin-4 in CD4 cells from patients with the hyper-IgE syndrome,' published in a 2002 issue of 'Clinical and Experimetnal Immunology.'

Examines the induction of immunologic memory after vaccination with Hemophilus influenzae type b (Hib) conjugate and acellular pertussis. Reduction of anti-Hib polysaccharide; Administration of polyribitolribosyl phosphate and Hib conjugate vaccines; Comparison between whole cell pertussis and acellular pertussis.