Pertussis seroprevalence among adults of reproductive age (20-39 years) in fourteen European countries.

The reported incidence of pertussis in European countries varies considerably. We aimed to study specific Bordetella pertussis seroprevalence in Europe by measuring serum IgG antibody levels to pertussis toxin (anti-PT IgG). Fourteen national laboratories participated in this study including Belgium, Denmark, Finland, Greece, Hungary, Italy, Lithuania, Malta, Norway, Poland, Portugal, Romania, Spain, and Sweden.

Serum reactome induced by Bordetella pertussis infection and Pertussis vaccines: qualitative differences in serum antibody recognition patterns revealed by peptide microarray analysis.

Background: Pertussis (whooping cough) remains a public health problem despite extensive vaccination strategies. Better understanding of the host-pathogen interaction and the detailed B. pertussis (Bp) target recognition pattern will help in guided vaccine design.

Two consecutive randomized controlled pertussis booster trials in children initially vaccinated in infancy with an acellular vaccine: The first with a five-component Tdap vaccine to 5-year olds and the second with five- or monocomponent Tdap vaccines at age 14-15 years.

Prior study children from a DTaP efficacy trial were recruited at ages 5 and 15 years to randomized booster trials addressing immunogenicity and reactogenicity; 475 preschool children received mixed or separate injections of a reduced antigen vaccine (Tdap5, Sanofi Pasteur MSD) and an inactivated polio vaccine, and 230 adolescents received the same or another booster vaccine (Tdap1, SSI, Denmark). Pre-vaccination antibody concentrations against pertussis antigens were significantly higher at 15 than 5 years of age, probably due to natural boosting between the studies. Tdap5 induced comparable anti-PT concentrations at both ages, but antibody responses were significantly higher to filamentous haemagglutinin, pertactin and fimbriae 2/3 in adolescents.

Analysis of Bordetella pertussis clinical isolates circulating in European countries during the period 1998-2012.

Despite more than 50 years of vaccination, pertussis is still an endemic disease, with regular epidemic outbreaks. With the exception of Poland, European countries have replaced whole-cell vaccines (WCVs) by acellular vaccines (ACVs) in the 1990s. Worldwide, antigenic divergence in vaccine antigens has been found between vaccine strains and circulating strains.

Investigations into the emergence of pertactin-deficient Bordetella pertussis isolates in six European countries, 1996 to 2012.

Pathogen adaptation has been proposed to contribute to the resurgence of pertussis. A striking recent example is the emergence of isolates deficient in the vaccine component pertactin (Prn). This study explores the emergence of such Prn-deficient isolates in six European countries.

Modeling rates of infection with transient maternal antibodies and waning active immunity: application to Bordetella pertussis in Sweden.

Serological surveys provide reliable information from which to calculate forces (instantaneous rates) of infection, but waning immunity and clinical consequences that depend on residual immunity complicate interpretation of results. We devised a means of calculating these rates that accounts for passively acquired maternal antibodies that decay or active immunity that wanes, permitting re-infection. We applied our method to pertussis (whooping cough) in Sweden, where vaccination was discontinued from 1979 to 1995.

Global population structure and evolution of Bordetella pertussis and their relationship with vaccination.

Bordetella pertussis causes pertussis, a respiratory disease that is most severe for infants. Vaccination was introduced in the 1950s, and in recent years, a resurgence of disease was observed worldwide, with significant mortality in infants. Possible causes for this include the switch from whole-cell vaccines (WCVs) to less effective acellular vaccines (ACVs), waning immunity, and pathogen adaptation.

Antibody responses to Bordetella pertussis Fim2 or Fim3 following immunization with a whole-cell, two-component, or five-component acellular pertussis vaccine and following pertussis disease in children in Sweden in 1997 and 2007.

Bordetella pertussis fimbriae (Fim2 and Fim3) are components of a five-component acellular pertussis vaccine (diphtheria-tetanus-acellular pertussis vaccine [DTaP5]), and antibody responses to fimbriae have been associated with protection. We analyzed the IgG responses to individual Fim2 and Fim3 in sera remaining from a Swedish placebo-controlled efficacy trial that compared a whole-cell vaccine (diphtheria-tetanus-whole-cell pertussis vaccine [DTwP]), a two-component acellular pertussis vaccine (DTaP2), and DTaP5. One month following three doses of the Fim-containing vaccines (DTwP or DTaP5), anti-Fim2 geometric mean IgG concentrations were higher than those for anti-Fim3, with a greater anti-Fim2/anti-Fim3 IgG ratio elicited by DTaP5.

Pulsed-field gel electrophoresis analysis of Bordetella pertussis isolates circulating in Europe from 1998 to 2009.

Between 1998 and 2009, Bordetella pertussis clinical isolates were collected during three periods, i.e., 1998 to 2001 (n = 102), 2004 to 2005 (n = 154), and 2007 to 2009 (n = 140), from nine countries with distinct vaccination programs, i.

Is adolescent pertussis vaccination preferable to natural booster infections?

Pertussis is still poorly controlled in both adolescents and adults. As a result, an adolescent pertussis booster vaccine dose has already been implemented or decided on in many countries. The reasons for this have been twofold: a worrying increase of infections in the target group of adolescents and a wish to prevent serious pertussis disease among young yet unvaccinated, and partly vaccinated, infants.

Pertussis vaccination in infancy lowers the incidence of pertussis disease and the rate of hospitalisation after one and two doses: analyses of 10 years of pertussis surveillance.

Objectives: Shortly after pertussis vaccination was reintroduced in Sweden in 1996, an intensified pertussis disease surveillance programme was set up. In this study, we report on in-depth analyses of age-dose-number-specific incidences and the rate of pertussis hospitalisation for children with no, 1 or 2 doses of an acellular pertussis vaccine before pertussis disease. Vaccine coverage, the timeliness of childhood vaccination and the effect of later than scheduled pertussis vaccination(s) are also examined.

Glycoconjugate vaccines and immune interactions, and implications for vaccination schedules.

Conjugate vaccines using diphtheria toxoid variant (CRM(197)), diphtheria toxoid and tetanus toxoid (TT) as carrier protein may induce immune interactions (interference or impairment as measured by lower antibody levels, or enhancement [higher antibody levels]) when coadministered with other vaccines. Immune enhancement occurs when two TT conjugates are coadministered. CRM(197) conjugate vaccines induce immune bystander interference when given with diphtheria-tetanus-acellular pertussis vaccines, which reduces responses to coadministered Haemophilus influenzae type b vaccine conjugated to TT.

SNP-based typing: a useful tool to study Bordetella pertussis populations.

To monitor changes in Bordetella pertussis populations, mainly two typing methods are used; Pulsed-Field Gel Electrophoresis (PFGE) and Multiple-Locus Variable-Number Tandem Repeat Analysis (MLVA). In this study, a single nucleotide polymorphism (SNP) typing method, based on 87 SNPs, was developed and compared with PFGE and MLVA. The discriminatory indices of SNP typing, PFGE and MLVA were found to be 0.

Appearance of Fim3 and ptxP3-Bordetella pertussis strains, in two regions of Sweden with different vaccination programs.

After introduction of a mono-component vaccine, containing only pertussis toxoid (PT), the incidence of pertussis was significantly higher in the Gothenburg area among children during the period October 1, 1997 until end of 2006 compared to the Rest of Sweden where a vaccine containing PT and two other pertussis antigens was used. To investigate a possible cause of this difference, the Bordetella pertussis populations in both regions were compared by determining the fimbrial serotype (Fim), the PFGE-type and the pertussis toxin promoter allele type (ptxP). Strains with the ptxP1 allele were successively replaced by ptxP3 strains producing more pertussis toxin.

Do we need a booster of Hib vaccine after primary vaccination? A study on anti-Hib seroprevalence in Sweden 5 and 15 years after the introduction of universal Hib vaccination related to notifications of invasive disease.

The prevalence of IgG ELISA antibodies against Haemophilus influenzae polyribosyl ribitol phosphate (anti-Hib) was studied in two Swedish seroepidemiologic materials. One study was performed in 1997 5 years after the introduction of universal Hib vaccination (N=3320). Ten years later, a similar study was carried out to analyze the effect of vaccination on anti-Hib prevalence (N=2383).

Antibody response patterns to Bordetella pertussis antigens in vaccinated (primed) and unvaccinated (unprimed) young children with pertussis.

In a previous study, it was found that the antibody response to a nonvaccine pertussis antigen in children who were vaccine failures was reduced compared with the response in nonvaccinated children who had pertussis. In two acellular pertussis vaccine efficacy trials in Sweden, we studied the convalescent-phase enzyme-linked immunosorbent assay (ELISA) geometric mean values (GMVs) in response to pertussis toxin (PT), filamentous hemagglutinin (FHA), pertactin (PRN), and fimbriae (FIM 2/3) in vaccine failures and controls with pertussis. In Germany, the antibody responses to Bordetella pertussis antigens PT, FHA, PRN, and FIM-2 were analyzed by ELISA according to time of serum collection after onset of illness in children with pertussis who were vaccine failures or who were previously unvaccinated.

Seroprevalence of pertussis antitoxin (anti-PT) in Sweden before and 10 years after the introduction of a universal childhood pertussis vaccination program.

The prevalence of IgG ELISA antibodies against pertussis toxin (anti-PT) was studied in two Swedish seroepidemiological studies. One was performed in 1997 when the new pertussis vaccination program was 1 year old (n = 3420). In 2007, when Pa vaccines had been used countrywide for 10 years in the universal child vaccination program, this study was repeated to analyze the effect of vaccination on anti-PT prevalence (n = 2379).

Kinetics and sensitivity of ELISA IgG pertussis antitoxin after infection and vaccination with Bordetella pertussis in young children.

Sera from 96 young children in a vaccine trial were analysed for kinetics of ELISA IgG anti-pertussis toxin (anti-PT) after a laboratory-verified pertussis infection. The antibody decay curves after infection were biphasic and similar in shape to those after vaccination. The change from a rapid to a slower decay after the peak occurred about 4-5 months from the first day of cough.