Diphtheria, tetanus and pertussis antibodies in 10-year-old children before and after a booster dose of three toxoids: implications for the timing of a booster dose.

Unlabelled: In an open study, 502 10-year-old children, who had received primary vaccination against diphtheria and tetanus in infancy and had varying histories of pertussis disease and vaccination, were vaccinated with diphtheria-tetanus vaccine (DT) alone or with the addition of 20 microg or 40 microg of pertussis toxoid. Diphtheria toxin neutralising antibodies, pertussis toxin IgG and tetanus toxoid IgG antibodies were measured before and 1 month after the booster. All toxoids were highly immunogenic.

Reduced immunogenicity of diphtheria and tetanus toxoids when combined with pertussis toxoid.

The effect of pertussis toxoid on the immunogenicity of diphtheria and tetanus toxoids (DT) was studied during a double blind efficacy trial of an acellular pertussis vaccine. Infants received DT with or without pertussis toxoid at 3, 5 and 12 months of age. Geometric mean concentrations were higher in the DT than in the DT-pertussis toxoid group 1 month (diphtheria toxoid 4.

Determination of pertactin IgG antibodies for the diagnosis of pertussis.

Objective: To compare increases in serum IgG antibody against pertactin with increases in IgG against pertussis toxin and filamentous hemagglutinin (FHA) in non-vaccinated children, children vaccinated with pertussis toxoid, and adults, all with culture-confirmed pertussis.

Methods: During a double-blind, placebo-controlled, efficacy trial of a monocomponent pertussis toxoid vaccine, acute and convalescent sera were obtained from study children and family members with suspected pertussis. In the present study, IgG antibodies against pertactin, pertussis toxin and FHA (determined by ELISA) were compared in 207 individuals with culture-verified pertussis and paroxysmal cough for >/= 21 days.

Immunologic and epidemiologic experience of vaccination with a monocomponent pertussis toxoid vaccine.

Pertussis re-emerged in Sweden with a cumulative incidence of about 60% during the first 10 years of life, when the locally produced cellular vaccine lost its efficacy around 1970 and general vaccination was discontinued in 1979. The epidemiology, clinical features, and immunology of pertussis and a monocomponent pertussis toxoid vaccine were studied in Göteborg, Sweden. After phase 1 and 2 studies, a randomized, double-blind, placebo-controlled trial of pertussis toxoid (PTox), compounded with diphtheria and tetanus toxoids, was administered to 3450 children according to the Swedish schedule at 3, 5, and 12 months of age.

Mass vaccination of children with pertussis toxoid--decreased incidence in both vaccinated and nonvaccinated persons.

During 1979-1995, there was no vaccination against pertussis in Sweden. With the aim of studying the epidemiology and transmission of pertussis, mass vaccination with pertussis toxoid of children born during the 1990s was instituted in the Göteborg area (population, 778,597) in 1995. Infants were offered 3 doses of pertussis toxoid combined with diphtheria and tetanus toxoids.

Serum immunoglobulin G antibody responses to Bordetella pertussis lipooligosaccharide and B. parapertussis lipopolysaccharide in children with pertussis and parapertussis.

Serum immunoglobulin G (IgG) antibodies against the lipooligosaccharide (LOS) of Bordetella pertussis and the lipopolysaccharide (LPS) of Bordetella parapertussis were measured by enzyme-linked immunosorbent assay in paired sera from 40 children with pertussis and 14 with parapertussis. Wide differences in the individual responses were noted. Both anti-LOS and -LPS IgG levels increased significantly in the children with pertussis, as did anti-LPS but not anti-LOS in those with parapertussis.

Immunogenicity and reactogenicity of diphtheria, tetanus and pertussis toxoids combined with inactivated polio vaccine, when administered concomitantly with or as a diluent for a Hib conjugate vaccine.

In an open trial, 400 infants were randomized to vaccination with a combined diphtheria-tetanus-pertussis-inactivated polio vaccine (DTaP-IPV) either mixed with a Haemophilus influenzae type b (Hib) tetanus toxoid conjugate immediately before injection (DTaP-IPV/Hib (mix)) or given concurrently with the Hib conjugate at separate injection sites (DTaP-IPV+Hib (sep)). The pertussis component consisted of pertussis toxoid alone. The vaccines were given intramuscularly at 3, 5 and 12 months of age.

Correlation between pertussis toxin IgG antibodies in postvaccination sera and subsequent protection against pertussis.

All acellular pertussis vaccines contain pertussis toxoid and induce protection against pertussis. This study investigated the relation between the postvaccination levels of pertussis toxin (PT) serum IgG and protection against pertussis. PT IgG was determined in sera obtained 21-77 days after the third vaccination from 813 children who received 3 doses of pertussis toxoid.

Vaccination of infants with a four-dose and a three-dose vaccination schedule.

Swedish infants were vaccinated with diphtheria, tetanus and pertussis toxoids, inactivated poliovirus vaccine and a Haemophilus influenzae type b - tetanus toxoid conjugate vaccine at 2, 4, 6 and 15 months (US vaccination program, 'US arm', n=118) or at 3, 5 and 12 months of age (Swedish vaccination program, 'Swedish arm', n=103). The antigen amounts in the diphtheria and tetanus vaccines were higher in the Swedish than in the US arm while the amounts in the other vaccines were the same in both arms. There were no serious side effects.

Parapertussis and pertussis: differences and similarities in incidence, clinical course, and antibody responses.

Objectives: To compare the incidence, clinical course, and serologic response to Bordetella antigens in patients with parapertussis and pertussis.

Design: Two studies were performed in Sweden during the 1990s, when pertussis vaccines were used only in clinical trials. Study I was a retrospective study of patients with positive Bordetella cultures obtained in clinical routine, and study II involved an active search for patients with Bordetella infections during a placebo-controlled trial of a pertussis toxoid vaccine.

Serum IgG antibody responses to pertussis toxin and filamentous hemagglutinin in nonvaccinated and vaccinated children and adults with pertussis.

Levels of IgG antibody to pertussis toxin (PT) and filamentous hemagglutinin (FHA) were measured in paired serum samples from 781 patients fulfilling at least one laboratory criterion for pertussis that was suggested by an ad hoc committee sponsored by the World Health Organization. The patients were participants or family members of participants in a double-blind efficacy trial of a monocomponent pertussis toxoid vaccine. Of 596 nonvaccinated children, 90% had significant (two-fold or more) rises in PT IgG and FHA IgG levels.

Immunity to pertussis. Not all virulence factors are protective antigens.

As with diphtheria, immunity to pertussis is complex because it involves both individual and community protection against infection with B. pertussis. Although B.

Standardization of acellular pertussis vaccine by assay of serum neutralizing antibodies to pertussis toxin (antitoxin): analogy with diphtheria toxoid.

Immunity conferred by vaccination with cellular pertussis vaccines and pertussis wanes so that adults are now the main reservoir of B. pertussis. Similar to diphtheria toxoid, acellular pertussis vaccines are suitable for vaccination of adults and it is probable that addition of pertussis toxoid to DT will be recommended for this age group.

Immunization of children with pertussis toxoid decreases spread of pertussis within the family.

Objective: In a previously reported double blind placebo-controlled trial it was shown that vaccination with pertussis toxoid during infancy reduced the incidence of pertussis in the vaccinees. Parents and siblings of participants in the trial were followed for pertussis to determine whether vaccination provided indirect protection of close contacts in a nonvaccinating country with a high incidence of pertussis.

Study Design: A group of 3450 infants were randomized to vaccination with diphtheria, tetanus and pertussis toxoids (DTPtxd) or to diphtheria and tetanus toxoids (DT).

Evaluation of PCR for diagnosis of Bordetella pertussis and Bordetella parapertussis infections.

PCR, using primers Plp1 and Plp2, was evaluated for the detection of DNA from Bordetella pertussis in bacterial strains and in nasopharyngeal samples from patients with a cough lasting at least 7 days. The assay could detect DNA from 6 CFU of B. pertussis/10 microl of sample.

Towards better pertussis vaccines.

Several recently completed trials have shown that acellular pertussis vaccines induce substantial protection against pertussis. They are considerably less reactogenic than whole-cell vaccines and, as they consist of only one or a few purified proteins, they can be expected to cause less severe adverse events. The optimal composition of acellular vaccines has not yet been determined.

Efficacy of a monocomponent pertussis toxoid vaccine after household exposure to pertussis.

In a double-blind, placebo-controlled efficacy trial of a monocomponent pertussis toxoid vaccine, 3450 infants were randomly assigned to vaccination with diphtheria-tetanus toxoids with or without pertussis toxoid at 3, 5, and 12 months of age. Study children and family members were investigated for possible pertussis with cultures, serology, and polymerase chain reaction. Efficacy was 71% after 3 dose when the World Health Organization case definition of pertussis (which includes paroxysmal cough for 21 days or longer) was used.

Unchanged efficacy of a pertussis toxoid vaccine throughout the two years after the third vaccination of infants.

Background: In a previously reported double blind efficacy trial of a pertussis toxoid vaccine, 3450 infants were randomized to receive diphtheria-tetanus toxoids with or without pertussis toxoid at 3, 5 and 12 months of age. Efficacy against pertussis as defined by the World Health Organization was 71% from 30 days after the third vaccination with an average follow-up of 17.5 months.