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A study aims to identify adverse events reported following licensed a trivalent live, attenuated influenza vaccine (LAIV-T) administration after licensure. Reports to Vaccine Adverse Event Reporting System in the first 2 seasons of LAIV-T use did not identify any unexpected serious risks with this vaccine when used according to approved indications.

Functional assays of antibody activity and enzyme-linked immunosorbent assays (ELISAs) of pertussis vaccine-induced antibodies correlate well enough with each other that it does not appear necessary to perform both types of tests. Blood samples for the comparisons were taken from infants participating in a clinical trial of the effectiveness of 13 new acellular pertussis vaccines, which use one or more protein components of the pertussis bacteria, and two standard whole-cell pertussis vaccines. ELISA results for four protein components were compared with results from the two functional assays. Results from one of the two assays were strongly associated with the ELISA results for pertussis toxin. Results from the other functional assay were strongly associated with the ELISA results for fimbrial protein. One type of vaccine that lacked fimbrial protein also responded strongly to this second assay. This vaccine had a particularly strong pertussis toxin response, suggesting there may be some crossover response., Objective. To examine the relationships between functional assays and antigen-specific enzyme immunoassays in sera from a multicenter trial of 13 different experimental acellular pertussis vaccines and 2 licensed whole-cell vaccines, and to determine whether correlations previously observed among assays of specimens from pertussis patients and whole-cell vaccines would apply to specimens from infants immunized with purified components in acellular vaccines. Methods. Postimmunization sera were assayed for immunoglobulin G antibodies to pertussis toxin (PT), filamentous hemagglutinin, pertactin (PRN), and a mixture of types 2 and 3 fimbriae (FIM) by enzyme-linked immunosorbent assay, for whole-cell agglutinins (AGGs) and for PT-neutralizing antibodies by the Chinese hamster ovary (CHO) cell assay. Assay results were compared for individual sera, as well as for geometric mean antibody concentrations or titers (GMTs) calculated by vaccine or overall. Results. For the 15 vaccines, the PT GMTs were highly correlated with the CHO assay GMTs (r = .92), and the FIM GMTs were highly correlated with the AGG GMTs (r = .96). For individual postvaccination sera, there was a significant correlation between the CHO titers and levels of antibody to PT whether the 15 vaccines were considered separately (.59 [less than or equal to] r [less than or equal to] .85) or combined (r = .81). For individual sera from infants immunized with the two whole-cell vaccines or any of the four acellular vaccines containing FIM, a strong correlation between AGG titer and FIM antibody was observed whether the vaccines were considered separately (.83 [less than or equal to] r [less than or equal to] .91) or together (r = .86). One vaccine without detectable FIM produced a measurable AGG response; for this vaccine, a moderate but significant correlation (R = .58) between PRN antibody and AGG titer was observed. Conclusion. These data indicate that appropriate antigen-specific enzyme-linked immunosorbent assays will furnish results similar to those provided by the CHO and AGG assays in the evaluation of the immunogenicity of component vaccines. Antibodies to FIM seem to include the most important AGGs; however, there is evidence that agglutination by PRN antibody may be detected in the absence of antibody to FIM. Pediatrics 1995;96:595 600, antibody, assay, diphtheria-tetanus-pertussis, pertussis, vaccine., ABBREVIATIONS. ELISA, enzyme-linked immunosorbent assay; CHO, Chinese hamster ovary; PT, pertussis toxin; IgG, immunoglobulin G; FHA, filamentous hemagglutinin; PRN, pertactin; FIM, fimbrial protein; AGG, agglutinins; DTP, diphtheria and tetanus toxoids [...]

Biologically active pertussis toxin may not be the cause of severe reactions in children vaccinated with the diphtheria-tetanus-pertussis (DTP) vaccine. Pertussis toxin is the part the vaccine that protects against the development of whooping cough. Among 60 children who had a severe reaction within 48 hours of receiving the DTP vaccine, 32 had seizures only, two had a fever of 40.5 deg C or more, four cried for three hours or more, six had seizures and a fever of 40.5 deg C or more, and two had seizures and cried for at least three hours. Ninety percent of the children who developed seizures had a fever of 38 deg C or more. Many had a personal or family history of seizures. Episodes of persistent crying were usually caused by a painful reaction at the injection site. Blood samples from children who had a severe reaction did not contain biologically active pertussis toxin.

Household contacts of primary pertussis cases were evaluated. Infection was determined by culture, direct fluorescent antibody assay, and serological criteria. Agglutinin titers and values of ELISA IgG and IgA antibodies to lymphocytosis-promoting factor, filamentous hemagglutinin, and pertactin were determined. In 39 households 255 subjects were exposed; 114 remained well (group 1), 53 had mild illness (group 2), and 88 had pertussis (group 3). The infection rates were 46% (group 1), 43% (group 2), and 80% (group 3). In a subgroup of subjects seen within 14–28 days of exposure, it was found that none with clinical pertussis had a value of IgG antibody to pertactin in acute-phase sera of ⩾50 ELISA units (EU) per mL or an agglutinin titer of >256. Of the primary cases, 53% were ⩾13 years of age. These data point out the importance of Bordetella pertussis infections in adolescents and adults as a source of infection in young children. Our subgroup data suggest that high values of antibody to pertactin and high agglutinin titers may be predictive of protection against clinical pertussis. [ABSTRACT FROM PUBLISHER]

University students with persistent cough of ⩾6 days' duration were evaluated for evidence of infection with Bordetella pertussis. Of 130 students studied during a 30-month period, 34 (26%) were found to have evidence of recent infections with B. pertussis. Infection was identified by direct fluorescent antibody assay of a nasopharyngeal specimen in one student and serologically in 33 additional subjects. B. pertussis was not recovered on culture of nasopharyngeal specimens from any subjects. Students with B. pertussis infection were identified in seven of the eight 3-month periods in which students were enrolled during the 30-month investigation, suggesting an endemic rather than epidemic pattern of infection in this university population. Illnesses of students with pertussis were similar to the illnesses of students without pertussis. The findings in this study suggest that adult populations in which endemic illness occurs at a relatively constant rate may be the reservoirs for pertussis outbreaks in susceptible children. Immunization programs in the future will need to employ booster doses for adults if complete control of B. pertussis infection is our goal. [ABSTRACT FROM PUBLISHER]

In industrialized nations, routine use of pertussis vaccines has shifted the burden of pertussis disease from middle childhood to one primarily affecting young infants, adolescents, and adults. Although generally not as severe as observed in infants, pertussis in adolescents and adults can be serious, and these older age groups are often the reservoir of infection for infants. With recognition of the increasing incidence of pertussis in older individuals, reduced-dose acellular pertussis vaccines combined with diphtheria and tetanus toxoids (Tdap) were developed for use in adolescents and adults. The goals of Tdap booster are to protect older vaccinees, reduce circulating disease, and thereby protect young infants.