Assuntos
Polissacarídeos Bacterianos/farmacologia , Salmonella typhi/imunologia , Febre Tifoide/prevenção & controle , Vacinas Tíficas-Paratíficas/farmacologia , Chile , Ensaios Clínicos como Assunto , Humanos , Polissacarídeos Bacterianos/imunologia , Salmonella typhi/isolamento & purificação , África do Sul , Febre Tifoide/imunologia , Febre Tifoide/microbiologia , Vacinas Tíficas-Paratíficas/imunologiaRESUMO
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. We report the efficacy in the subgroup of children who were exposed to pertussis in the household. Among study children exposed to pertussis in the household from the day of the third vaccination, 20 of 99 (20%) recipients of diphtheria-tetanus-pertussis toxoids vaccine and 64 of 79 (81%) recipients of diphtheria-tetanus toxoids vaccine had pertussis fulfilling criteria of the World Health Organization. The vaccine efficacy was 75% (95% confidence intervals 64% to 84%). In children who had received only two doses at the time of household exposure, vaccine efficacy was 66% (95% confidence intervals 15% to 90%) based on 4 cases among 32 household-exposed recipients of diphtheria-tetanus-pertussis toxoids vaccine and 13 cases among 35 household-exposed recipients of diphtheria-tetanus toxoids vaccine. In conclusion, the pertussis toxoid vaccine provides protection against pertussis both after household and community exposure.
Assuntos
Vacina contra Coqueluche/administração & dosagem , Toxoides/administração & dosagem , Coqueluche/prevenção & controle , Toxoide Diftérico/administração & dosagem , Vacina contra Difteria e Tétano , Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Método Duplo-Cego , Saúde da Família , Humanos , Lactente , Toxoide Tetânico/administração & dosagem , Vacinas Combinadas/administração & dosagem , Coqueluche/diagnósticoAssuntos
Anticorpos Antibacterianos/análise , Vacinas Bacterianas/administração & dosagem , Vacinas Anti-Haemophilus , Haemophilus influenzae/imunologia , Polissacarídeos Bacterianos/administração & dosagem , Toxoide Tetânico/administração & dosagem , Hidróxido de Alumínio , Cápsulas Bacterianas , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Lactente , Polissacarídeos Bacterianos/imunologia , Fatores de TempoRESUMO
The safety and immunogenicity of Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) alone, or covalently bound to tetanus toxoid in saline solution (Hib-TT) or adsorbed onto AI(OH)3 (Hib-TT ads), were evaluated after one injection into 18- to 23-month-old healthy children in Sweden. No side reactions were elicited by Hib CPS; side reactions elicited by the two conjugates were similar and comparable to those reported for diphtheria and tetanus toxoids adsorbed. Hib-TT was the most immunogenic of the three vaccines, eliciting about 10-fold higher antibody levels than Hib CPS; of 28 vaccinees, all had greater than 1.0 microgram Ab/mL serum after immunization with Hib-TT. Increases of Hib CPS antibodies within immunoglobulin classes induced by the three vaccines were, in decreasing order, IgG greater than IgM greater than IgA. Within IgG subclasses, rises in IgG1 Hib CPS antibodies were the most frequent, followed by IgG2; some vaccinees with high postimmunization levels also had rises in IgG3 and one in IgG4. Immunization-induced Hib CPS antibodies were bactericidal. Hib-TT also elicited higher levels of tetanus toxoid antibodies than Hib-TT ads; these tetanus toxoid antibodies neutralized tetanus toxin in vivo.
Assuntos
Vacinas Bacterianas/imunologia , Vacinas Anti-Haemophilus , Polissacarídeos Bacterianos/imunologia , Toxoide Tetânico/imunologia , Hidróxido de Alumínio/imunologia , Anticorpos Antibacterianos/análise , Cápsulas Bacterianas , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Lactente , MasculinoRESUMO
An enzyme-linked immunosorbent assay (ELISA) measuring, in serum, immunoglobulin G (IgG), IgM, and IgA to Vi capsular polysaccharide antigen that was tyraminated (Vi-Tyr) to increase its binding efficiency to microtiter plates was compared with the standard passive hemagglutination assay (PHA) as a screening test for chronic Salmonella typhi carriers. Initially, three populations were evaluated: 22 healthy U.S. adults, 17 young Chilean adults with acute typhoid fever, and 51 Chileans who had bacteriologically confirmed S. typhi chronic carriage. IgG-specific Vi-Tyr antibodies were preferentially present in the S. typhi chronic carrier state. A total of 44 of 51 (81%) chronic carriers, 0 of 22 (0%) healthy U.S. adults, and 2 of 17 (12%) Chileans with acute typhoid fever had reciprocal IgG Vi-Tyr ELISA antibody titers in serum of greater than or equal to 200. The IgG Vi-Tyr ELISA was then compared with the PHA as a screening test for chronic carriers in 141 Chilean female food handlers. One woman was serologically incriminated as a carrier by both the IgG ELISA and PHA; her coprocultures were positive for S. typhi. One other woman, identified as a carrier by PHA, was negative by culture and IgG ELISA. The IgG Vi-Tyr ELISA is as sensitive as the PHA (86 versus 76%) and as specific (95 versus 95%) in screening for chronic carriers.
Assuntos
Anticorpos Antibacterianos/análise , Portador Sadio/diagnóstico , Ensaio de Imunoadsorção Enzimática , Polissacarídeos Bacterianos , Salmonella typhi/imunologia , Febre Tifoide/diagnóstico , Doença Aguda , Adulto , Antígenos de Bactérias/imunologia , Portador Sadio/epidemiologia , Chile , Doença Crônica , Feminino , Testes de Hemaglutinação , Humanos , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Febre Tifoide/epidemiologia , Estados UnidosAssuntos
Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Salmonella typhi/imunologia , Adolescente , Adulto , Vacinas Bacterianas/efeitos adversos , Chile , França , Testes de Hemaglutinação , Humanos , Maryland , Antígenos O , Polissacarídeos Bacterianos/imunologia , Febre Tifoide/epidemiologiaRESUMO
Five cases of HITB maningitis occurred within six months in an enclosed population of 28 to 32 chronically ill children. Studies of nasopharyngeal carriage and serum HITB anticapsular antibodies were started after the third case occurred. Two patients had low (less than 0.04 and 0.05mug/ml) antibodies and were not carriers when studied prior to onset of their disease. The carriage rate was approximately 20% among the children. Carriage was usually prolonged, and acquisition was not prevented by high antibody levels. Attempts to arrest this outbreak with type b polysaccharide immunization and ampicillin therapy are discussed in the context of HITB meningitis as a contagious disease.