Invasive Haemophilus influenzae Infections after 3 Decades of Hib Protein Conjugate Vaccine Use.

Haemophilus influenzae serotype b (Hib) was previously the most common cause of bacterial meningitis and an important etiologic agent of pneumonia in children aged <5 years. Its major virulence factor is the polyribosyl ribitol phosphate (PRP) polysaccharide capsule. In the 1980s, PRP-protein conjugate Hib vaccines were developed and are now included in almost all national immunization programs, achieving a sustained decline in invasive Hib infections. However, invasive Hib disease has not yet been eliminated in countries with low vaccine coverage, and sporadic outbreaks of Hib infection still occur occasionally in countries with high vaccine coverage. Over the past 2 decades, other capsulated serotypes have been recognized increasingly as causing invasive infections. H. influenzae serotype a (Hia) is now a major cause of invasive infection in Indigenous communities of North America, prompting a possible requirement for an Hia conjugate vaccine. H. influenzae serotypes e and f are now more common than serotype b in Europe. Significant year-to-year increases in nontypeable H. influenzae invasive infections have occurred in many regions of the world. Invasive H. influenzae infections are now seen predominantly in patients at the extremes of life and those with underlying comorbidities. This review provides a comprehensive and critical overview of the current global epidemiology of invasive H. influenzae infections in different geographic regions of the world. It discusses those now at risk of invasive Hib disease, describes the emergence of other severe invasive H. influenzae infections, and emphasizes the importance of long-term, comprehensive, clinical and microbiologic surveillance to monitor a vaccine's impact.

Routine exercise alters measures of immunity and the acute phase reaction.

PURPOSE: To expand our understanding of the overall anti-inflammatory nature of routine exercise; we compared resting blood values from adults who habitually undertake frequent, moderate levels of exercise to reference interval values assumed to reflect values largely from non-exercisers. This information would be useful for clinicians interpreting blood tests assessing inflammatory, immune and acute phase responses. METHODS: Blood samples were collected from 119 community adult self-reported routine exercisers (61 males and 58 females aged 18-60 years). Samples were analysed for 20 cellular and non-cellular biomarkers which included 11 immunological and 9 acute phase reactants. These data were compared to reference intervals from the same hospital laboratory that performed the analyses on our participants' samples. Individual analyte values were also compared with participants' self-reported 150 day exercise patterns which included exercise frequency, intensity and duration. RESULTS: In general, mean values for routine exercise participants fell at the lower end of laboratory reference interval for most inflammatory analytes. More than 10 % of participants had numbers of CD19(+), CD8(+) and 16/56(+) NK cells below the low end of the respective reference interval. More than 10 % of observed acute phase reactant values (for C3, haptoglobin and ferritin) were also below the low end of the reference interval. At rest IgM (r = -0.22) and IgG (r = -0.31) values correlated negatively (p < 0.05) with exercise load. CONCLUSIONS: Routine exercise appears to lower resting numbers of a variety of immune cell-types as well as the concentration of several classical acute phase reactants. These wide-ranging systemic effects are presumably adaptive changes, not pathology and collectively confirm the well-reported and clinically important anti-inflammatory effects of exercise.

The impact of the changing pneumococcal national immunisation program among older Australians.

Australia has a universal infant pneumococcal conjugate vaccination program and until recently a universal pneumococcal polysaccharide vaccine program for non-Indigenous adults aged ≥65 years and Indigenous adults aged ≥50 years. We documented the impacts of infant and adult vaccination programs on the epidemiology of invasive pneumococcal disease (IPD) in Indigenous and non-Indigenous adults. IPD notifications from the National Notifiable Disease Surveillance System were analysed from 2002 to 2017, grouped by age, vaccine serotype group and Indigenous status. Since the universal funding of infant and elderly pneumococcal vaccination programs in January 2005, total IPD decreased by 19% in non-Indigenous adults aged ≥65 years but doubled in Indigenous adults aged ≥50 years. Vaccine uptake was suboptimal in both groups but lower in Indigenous adults. IPD due to the serotypes contained in the pneumococcal conjugate vaccines (PCV) except for serotype 3 declined markedly over the study period but were replaced by non-PCV serotypes. Serotype 3 is currently the most common in older adults. In the populations eligible for the adult 23-valent pneumococcal polysaccharide vaccine (23vPPV) program, IPD rates due to its exclusive serotypes increased to a lower extent than non-vaccine types. In 2017, non-vaccine serotypes accounted for most IPD in the older population eligible for the 23vPPV program, while it's eleven exclusive serotypes accounted for the majority of IPD in younger adults. Infant and adult pneumococcal vaccination programs in Australia have shaped the serotype-specific epidemiology of IPD in older adults. IPD remains a significant health burden for the Indigenous population. Herd immunity impact is clear for PCV serotypes excluding serotype 3 and serotype replacement is evident for non-PCV serotypes. The adult 23vPPV immunisation program appears to have partially curbed replacement with IPD due to its eleven exclusive serotypes, highlighting a potential benefit of increasing adult 23vPPV coverage in Australia.

The effect of exercise on innate mucosal immunity.

METHODS: The authors conducted a prospective observational study comparing salivary lactoferrin and lysozyme concentration over 5 months (chronic changes) in elite rowers (n=17, mean age 24.3+/-4.0 years) with sedentary individuals (controls) (n=18, mean age=27.2+/-7.1 years) and a graded exercise test to exhaustion (acute changes) with a cohort of elite rowers (n=11, mean age 24.7+/-4.1). RESULTS: Magnitudes of differences and changes were interpreted as a standardised (Cohen's) effect size (ES). Lactoferrin concentration in the observational study was approximately 60% lower in rowers than control subjects at baseline (7.9+/-1.2 microg/ml mean+/-SEM, 19.4+/-5.6 microg/ml, p=0.05, ES=0.68, 'moderate') and at the midpoint of the season (6.4+/-1.4 microg/ml mean +/- SEM, 21.5+/-4.2 microg/ml, p=0.001, ES=0.89, 'moderate'). The concentration of lactoferrin at the end of the study was not statistically significant (p=0.1) between the groups. There was no significant difference between rowers and control subjects in lysozyme concentration during the study. There was a 50% increase in the concentration of lactoferrin (p=0.05, ES=1.04, 'moderate') and a 55% increase in lysozyme (p=0.01, ES=3.0, 'very large') from pre-exercise to exhaustion in the graded exercise session. CONCLUSION: Lower concentrations of these proteins may be indicative of an impairment of innate protection of the upper respiratory tract. Increased salivary lactoferrin and lysozyme concentration following exhaustive exercise may be due to a transient activation response that increases protection in the immediate postexercise period.

Probiotics, immunity and exercise: a review.

Nutritional practices that promote good health and optimal athletic performance are of interest to athletes, coaches, exercise scientists and dietitians. Probiotic supplements modulate the intestinal microbial flora and offer promise as a practical means of enhancing gut and immune function. The intestinal microbial flora consists of diverse bacterial species that inhabit the gastrointestinal tract. These bacteria are integral to the ontogeny and regulation of the immune system, protection of the body from infection, and maintenance of intestinal homeostasis. The interaction of the gut microbial flora with intestinal epithelial cells and immune cells exerts beneficial effects on the upper respiratory tract, skin and uro-genital tract. The capacity for probiotics to modulate perturbations in immune function after exercise highlight their potential for use in individuals exposed to high degrees of physical and environment stress. Future studies are required to address issues of dose-response in various exercise settings, the magnitude of species-specific effects, mechanisms of action and clinical outcomes in terms of health and performance.

Nontypeable Haemophilus influenzae: pathogenesis and prevention.

In this paper, we describe the ability of nontypeable Haemophilus influenzae (NTHi) to coexist with the human host and the devastating results associated with disruption of the delicate state of balanced pathogenesis, resulting in both acute and chronic respiratory tract infections. It has been seen that the strains of NTHi causing disease show a marked genetic and phenotypic diversity but that changes in the lipooligosaccharide (LOS) and protein size and antigenicity in chronically infected individuals indicate that individual strains of NTHi can remain and adapt themselves to avoid expulsion from their infective niche. The lack of reliance of NTHi on a single mechanism of attachment and its ability to interact with the host with rapid responses to its environment confirmed the success of this organism as both a colonizer and a pathogen. In vitro experiments on cell and organ cultures, combined with otitis media and pulmonary models in chinchillas, rats, and mice, have allowed investigations into individual interactions between NTHi and the mammalian host. The host-organism interaction appears to be a two-way process, with NTHi using cell surface structures to directly interact with the mammalian host and using secreted proteins and LOS to change the mammalian host in order to pave the way for colonization and invasion. Many experiments have also noted that immune system evasion through antigenic variation, secretion of enzymes and epithelial cell invasion allowed NTHi to survive for longer periods despite a specific immune response being mounted to infection. Several outer membrane proteins and LOS derivatives are discussed in relation to their efficacy in preventing pulmonary infections and otitis media in animals. General host responses with respect to age, genetic makeup, and vaccine delivery routes are considered, and a mucosal vaccine strategy is suggested.

Increased intestinal permeability as a risk factor for type 2 diabetes.

AIM: Relationships between the intestinal microbiota, intestinal permeability and inflammation in the context of risk for obesity-associated disease continue to be of interest. The aim of the study was to examine the associations between intestinal permeability and type 2 diabetes (T2D). METHODS: A total of 130 individuals with T2D (age: 57.5±6.2 years (mean±SD); BMI: 30.4±3.2; 45% female) and 161 individuals without T2D (age: 37.4±12.5 years; BMI: 25.1±3.9; 65% female) were included in the study. Assessment of intestinal permeability included measurement of circulating lipopolysaccharide (LPS), LPS-binding protein (LBP) and intestinal fatty acid binding protein (iFABP) concentrations, which were used for calculation of a derived permeability risk score (PRS). Associations between permeability measures and T2D status were assessed using logistic regression models. RESULTS: LBP (∼34%, P<0.001), iFABP (∼46%, P<0.001) and the PRS (∼24% P<0.001) were all significantly higher in the T2D affected individuals. Individuals with a PRS in the upper tertile were 5.07 times more likely (CI: 1.72-14.95; P=0.003) to have T2D when models were adjusted for age, sex and BMI. There was a trend towards improved prediction when including the PRS in models containing age, sex and BMI (AUC: 0.954 versus 0.962; P=0.06). CONCLUSION: These data demonstrate differences in measures of intestinal permeability between individuals with and without T2D. The utility of using intestinal permeability measures as a tool for predicting T2D risk in at risk individuals should be further investigated.

Haemophilus influenzae oral whole cell vaccination for preventing acute exacerbations of chronic bronchitis.

BACKGROUND: Acute bronchitis leading to ongoing exacerbations is a serious condition predisposed to by viruses, bacteria or environmental factors. It can be fatal. Antibiotic therapy is not particularly useful. An oral Haemophilus influenzae vaccine has been developed. OBJECTIVES: To assess the effects of an oral, monobacterial whole-cell, killed, nontypeable H. influenzae vaccine in protecting against recurrent acute episodes in chronic bronchitis. SEARCH STRATEGY: In this updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to January Week 4 2006), EMBASE (1990 to September 2005) and ISI Current Contents (2004 to May 2006). SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing the effects of the H. influenzae vaccine on patients with recurrent acute exacerbations of chronic bronchitis were included when there was overt matching of the vaccine and placebo groups on clinical grounds. DATA COLLECTION AND ANALYSIS: Three authors extracted data and assessed trial quality independently from original records and publications for incidence and severity of bronchitis episodes and carriage rate of nontypeable H. influenzae measured in the upper respiratory tract every three months following vaccination. MAIN RESULTS: Six trials were included in the study with a total of 440 participants. The vaccine reduced the incidence of bronchitic episodes at three months after vaccination (rate ratio is 0.69; 95% CI 0.41 to 1.14) and at six months after vaccination (rate ratio 0.82; 95% CI 0.62 to 1.09). If these results been statistically significant, they would have represented a reduction in acute bronchitic attacks for vaccinated individuals of 31% at three months, and 18% at six. The effect had disappeared by nine months. The severity of exacerbations in the treatment group, as measured by requirement to prescribe antibiotics, was likewise reduced by 58% at three months (Peto odds ratio = 0.42; 95% CI 0.16 to 1.13), and by 65% at six months (Peto odds ratio = 0.35; 95% CI 0.16 to 0.75). AUTHORS' CONCLUSIONS: Vaccinating patients with recurrent acute exacerbations of chronic bronchitis in the autumn may reduce the number and severity of exacerbations over the following winter. A large clinical trial is needed.

Isolation of human IgA and IgM from normal serum using polyethylene glycol precipitation and affinity chromatography.

A simple method is described for the preparation of highly purified IgA and IgM from small volumes of human serum. Enriched IgM and IgA fractions were prepared by precipitation with 7% (w/v) and 14% (w/v) polyethylene glycol respectively. This was followed by affinity chromatography and gel filtration. The final recovery of both IgA and IgM was approximately 30%. The purified preparations obtained were characterized by immunoelectrophoresis, double immunodiffusion, radial immunodiffusion, radioimmunoassay and gel filtration.

Measurement of lysozyme by an enzyme-linked immunosorbent assay.

In this study an enzyme-linked immunosorbent assay has been developed for the determination of lysozyme in saliva, serum and urine. The assay relies on the detection of specific protein rather than lytic activity, a property which has been shown to be most suitable for the quantitation of lysozyme in mucin containing substances. Our results indicate that no pretreatment is necessary for the immunochemical method. The assay is sensitive to concentrations as low as 1 microgram lysozyme/l. The intra-assay and inter-assay coefficients of variation were 5.9% and 15.8% respectively. The lysozyme level in whole saliva was 55.53 +/- 30.35 mg/l, in serum the level was 0.64 +/- 0.15 mg/l and in urine it was 0.17 +/- 0.22 mg/l. Comparisons between immunochemical determination and lytic assays showed a good correlation (serum, r = 0.79, P less than 0.01; saliva, r = 0.85, P less than 0.005; treated saliva, r = 0.96, P less than 0.001).

Radioimmunoassay of human IgG, IgA and IgM.

Radioimmunoassay procedures for the quantitation of nanogram quantities of human immunoglobulin are described. The techniques have been successfully used to measure immunoglobulin secretion in culture supernatants by cultured human lymphocytes. Compared with previously published assays to assess lymphocyte function in vitro these procedures are simple, quick and reliable. A comparison of double-antibody and solid-phase radioimmunoassay is made. Similar sensitivity and variability in IgG and IgA assays were observed but it was not possible to develop a reliable double antibody radioimmunoassay for IgM. The solid-phase assay has several advantages over the double-antibody radioimmunoassays being quick to perform and using standard commercial reagents without necessity for exhaustive absorption.

Secondary structure and molecular analysis of interstrain variability in the P5 outer-membrane protein of non-typable Haemophilus influenzae isolated from diverse anatomical sites.

The sequence of the non-typable Haemophilus influenzae (NTHi) P5 outer-membrane protein from a range of clinical isolates is presented and represents the first analysis of the heterogeneity in P5 from NTHi isolates from diverse anatomical sites. The basis of the previously observed inter-strain variation in the electrophoretic mobility is attributed to heterogeneity in three hypervariable regions. Alignment of the P5 sequences identified regions which are highly conserved and align with the transmembrane region predicted for the homologous Escherichia coli protein, OmpA. Variable regions correspond to surface-exposed loops, of which the first loop falls into subclasses. However, these subclasses fail to correlate with anatomical predisposition. Although P5 has been proposed as a fimbrial protein composed of coiled coils, both structural analysis by circular dichroism of purified P5 and computer analysis of the multiply aligned sequences predict a high proportion of beta strand with no evidence of coiled coil structure. A detailed model of P5 is presented.

Outer-membrane antigen expression by Moraxella (Branhamella) catarrhalis influences pulmonary clearance.

Moraxella (Branhamella) catarrhalis is a common respiratory tract pathogen in man. The bacterium shows a strong tendency to form aggregates in vitro. A variant strain of M. catarrhalis that showed a reduced tendency to form aggregates was selected by successive in-vitro passage in broth culture from which aggregates had settled. The non-clumping variant strain showed alteration in expression of outer-membrane antigens, including the HMW-OMP, an outer-membrane protein of c. 200 kDa, outer-membrane protein CD and lipo-oligosaccharide. A mouse model for pulmonary challenge with M. catarrhalis revealed significant differences in the rate of clearance of the isogenic variant strains from the lung. The parent strain caused enhanced recruitment of neutrophils to the lung and more rapid clearance of bacteria from the lungs in comparison to the non-clumping variant. It is concluded that alteration of expression of surface molecules by M. catarrhalis has a significant impact in an in-vivo model of pulmonary clearance.

Biotypes of Haemophilus parainfluenzae from the respiratory secretions in chronic bronchitis.

A total of 2401 isolates of Haemophilus parainfluenzae was isolated from respiratory secretions of 36 healthy adults and 128 patients with chronic bronchitis over a period of 1 year. The isolates were allocated to eight biotypes, by their production of indole, urease and ornithine decarboxylase. Biotypes I and II constituted most of the isolates of H. parainfluenzae from the oropharynx of controls (75%) and chronic bronchitics (c. 90%). Among the patients, there was no difference in the isolation rate between oropharyngeal swabs and sputum specimens. Biotypes III, IV, VI, VII and VIII were isolated less frequently, as was a new taxon defined here as biotype V which does not produce indole, urease or ornithine decarboxylase. Biotype III was isolated significantly less frequently from cases of chronic bronchitis than from controls, whereas biotype II was isolated somewhat more frequently from the patients, especially during acute episodes.

Validation of the rosette inhibition test for the detection of early pregnancy in women.

The authors validated use of the rosette inhibition test for the detection of early pregnancy factor (EPF) in human pregnancy, first by optimizing conditions for the assay, using known pregnant and nonpregnant sera, and second, by examining the performance of this assay in three clinical situations: a "blind" study involving coded first-trimester sera showed 80% correlation with pregnancy status; serial assay of EPF activity in sera collected from normal women attempting to conceive, correlated with human chorionic gonadotropin beta-subunit (beta-hCG) levels and pregnancy status; a longitudinal study of serial serum samples through two normal pregnancies showing the continued presence of EPF until the early third trimester in each case. It was concluded that with the rosette inhibition assay, consistent demonstration of a pregnancy-associated substance (EPF) could be obtained.

Early pregnancy factor as a monitor for fertilization in women wearing intrauterine devices.

Measurement of early pregnancy factor (EPF) by the rosette inhibition test was performed on serum samples from 14 women using intrauterine devices (IUDs). Serial blood samples taken during the luteal phase of 23 cycles demonstrated in six of the cycles a transient appearance of EPF during the 6- to 8-day period following ovulation. In contrast, no EPF activity was found in sera obtained from women in whom fertilization was prevented, either by sexual abstinence or tubal ligation. These observations support the postulate that the IUD functions by the prevention of implantation of the fertilized ovum, rather than by preventing fertilization.

Early pregnancy factor: its role in mammalian reproduction--research review.

An immunosuppressive early pregnancy factor associated with mammalian reproduction is currently attracting considerable interest. Research into its detection, site of production, distribution, immunosuppressive property, characterization, and application is in progress in a number of laboratories. This review aims to crystallize the current research findings and to identify significant areas for further investigation and application.

C-reactive protein: a critical review.

We have reviewed the literature to determine the value of C-reactive protein (CRP) measurements in the diagnosis and management of a wide range of conditions. CRP levels are of value in 6 clinical situations: (a) monitoring the response to antibiotic treatment in patients with known bacterial infections, (b) in obstetric patients with premature rupture of membranes, a rise in CRP can give early warning of intrauterine infections, (c) differentiation between active disease and infections in patients with systemic lupus and ulcerative colitis where the level of response to active disease has been previously established, (d) as a measure of disease activity and response to disease-modifying drugs in rheumatoid arthritis, (e) early detection of complications in postoperative patients, (f) in differentiating between infection and graft-versus-host-disease in bone marrow transplant patients. CRP levels have been used in an attempt to differentiate between bacterial and viral infections in various clinical situations, however the published literature does not support this role.

In vitro susceptibility patterns of nonserotypable Haemophilus influenzae from patients with chronic bronchitis.

The antimicrobial susceptibility patterns of 76 nonserotypable Haemophilus influenzae (biotypes I-IV) from patients with chronic bronchitis were compared against ten orally administered antimicrobial agents. In addition the sputum ampicillin concentrations one hour after standard therapy were determined in five patients with chronic bronchitis. Ampicillin resistance was demonstrated in one strain (biotype IV) which produced beta-lactamase and two strains (biotype II) with innate resistance (MIC = 4 mg/l). Resistance to trimethoprim, chloramphenicol, ciprofloxacin and cefaclor was not detected. The incidence of resistance to tetracycline was 0.5% and cephalexin 13.2%. A high incidence of resistance to erythromycin (95%) was noted. There was no association between resistance and biotype of nonserotypable H. influenzae. The sputum ampicillin concentrations from four out of five patients given standard antibiotic doses were shown to be sufficient to inhibit the growth of the majority of nonserotypable H. influenzae strains one hour after treatment. This study shows that the incidence of nonserotypable H. influenzae resistant to ampicillin is low in this community but that resistance levels to erythromycin, commonly prescribed for the management of acute bronchitis, are high. Regular sensitivity screens are important in monitoring the value of various antibiotic regimens in the management of acute bronchitis.

Evaluation of a selective medium for the isolation and differentiation of Haemophilus influenzae and Haemophilus parainfluenzae from the respiratory tract of chronic bronchitics.

Respiratory tract specimens from chronic bronchitic patients were cultured for Haemophilus species on conventional chocolate agar and a modified sucrose medium in order to determine the accuracy of the new medium in differentiating Haemophilus influenzae from Haemophilus parainfluenzae strains. Haemophilus influenzae biotypes II and III and Haemophilus parainfluenzae biotypes I and II were found to be the predominant strains isolated from the respiratory tract. The modified sucrose medium was found to be a rapid and reliable means of differentiating Haemophilus influenzae from Haemophilus parainfluenzae by sucrose fermentation, on initial isolation.