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As new vaccines are developed, novel adjuvants may play an important role in eliciting an effective immune response. We evaluated the safety and adjuvant properties of monophosphoryl lipid A (MPL in 129 healthy toddlers immunized with two doses of nine-valent pneumococcal-CRM(197) protein conjugate vaccine (PCV9) combined with 10, 25, or 50 micro g of MPL with or without alum (AlPO(4)). Vaccine-specific humoral and cell-mediated responses were examined following the second dose of study vaccine. All doses of MPL were well-tolerated and a dose-dependent effect of MPL on specific cellular responses was observed. The 10 micro g MPL dose significantly enhanced CRM(197)-specific T-cell proliferation (P=0.02) and interferon-gamma (INF-gamma) production (P=0.009) compared to responses of controls who received PCV9 with AlPO(4). In contrast, CRM(197)-specific T-cell proliferation and interferon-gamma production of the 50 micro g MPL/AlPO(4) group were decreased when compared to controls although these differences did not reach statistical significance. IL-5 and IL-13 responses after immunization showed a similar pattern with increased production in the 10 micro g MPL group and decreased production in the 50 micro g MPL/AlPO(4) group compared to controls. There were no differences in serum IgG antibody concentrations to the nine vaccine pneumococcal capsular polysaccharides and carrier protein between the MPL-containing and control vaccine groups. These findings demonstrate a dose-dependent effect of MPL on T-helper cell type 1 (TH-1) responses to the carrier protein and also suggest an effect on T-helper cell type 2 (TH-2) responses.

Background: The goal of the trial was to determine the efficacy of a multicomponent acellular pertussis vaccine against Bordetella illnesses in comparison with a whole-cell product and DT., Design: In a randomized, double-blind fashion, 2- to 4-month-old infants received 4 doses of either DTP or DTaP vaccine at 3, 4.5, 6, and 15 to 18 months of age. The controls received 3 doses (3, 4.5, 15 to 18 months of age) of DT vaccine. The DTP vaccine was Lederle adsorbed vaccine (licensed in the United States) and DTaP was Lederle/Takeda adsorbed vaccine. Follow-up for vaccine efficacy started 2 weeks after the third dose (DTP/DTaP) and at the same age (6.5 months) in DT recipients. Reactogenicity of all doses of all three vaccines was documented by standardized parent diary cards. In addition, all subjects were monitored for respiratory illnesses and serious adverse events by biweekly phone calls., Results: From May 1991 to January 1993, a total of 10 271 infants were enrolled: 8532 received either DTP or DTaP and 1739 received DT. Specific efficacy against B pertussis infections with cough >/=7 days duration was 83% (95% confidence interval [CI]: 76-88) and 72% (95% CI: 62-79) for DTP and DTaP, respectively; results for DTP and DTaP based on >/=21 days of cough with either paroxysms, whoop or posttussive vomiting (PWV) were 93% (95% CI: 89-96) and 83% (95% CI: 76-88), respectively. For DTaP vaccine, efficacy was higher after the fourth dose as compared with its efficacy after the third dose (78% vs 62% for cough >/=7 days and 85% vs 76% for cough >/=21 days with PWV). For DTP vaccine, efficacy was less varied after the third and fourth dose (78% vs 85% for cough >/=7 days and 93% vs 93% for cough >/=21 days with PWV). In contrast with DTP, the DTaP vaccine had some efficacy against B parapertussis infection (point estimate for cough >/=7 days: 31% [95% CI: -10-56]). All vaccines were generally well-tolerated. However, side reactions were significantly less after DTaP compared with DTP., Conclusions: Like other multicomponent acellular pertussis vaccines, the Lederle/Takeda DTaP vaccine demonstrated good efficacy against mild and typical pertussis due to B pertussis infections. Interestingly, it also may have some efficacy against B parapertussis. Based on the results of this trial, the vaccine was licensed in the United States in December 1996 for all 5 doses of the currently recommended immunization schedule in this country.

Minor adverse events were evaluated in a comparative efficacy trial in Germany in infants who received either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. Vaccinees received four doses (at three, four-and-a half, six and 15-18 months of age) of either DTP or DTaP vaccine or three doses (at three, four-and-a half and 15-18 months of age) of DT vaccine. The reactogenicity analysis included 4,273 DTaP, 4,259 DTP and 1739 DT vaccinees. Local reactions (erythema and induration) and systemic events (fever, fretfulness, drowsiness and anorexia) were more common after each dose of DTP vaccine than after the DTaP and DT vaccine doses. Erythema, induration and fever increased in frequency in DTaP and DT recipients with increasing series number. Erythema, induration and fever after the first two doses of vaccine were more frequent in DT recipients than DTaP vaccinees. Antipyretics were more commonly used in DTP recipients than in DTaP vaccinees.

Severe adverse events were evaluated in a comparative efficacy trial in Germany in infants who received either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. Vaccinees received four doses (at three, four-and-a half, six and 15-18 months of age) of either DTP or DTaP vaccine or three doses at three, four-and-a half and 15-18 months of age) of DT vaccine. The analysis included 4,273 DTaP recipients, 4,259 DTP recipients and 1,739 DT vaccinees. Convulsions within three days of vaccination occurred in 1/15,912 doses in DTaP recipients and 1/3,926 doses in DTP vaccinees (p = 0.22). Persistent inconsolable crying was more common in DTP vaccinees (1/113 doses) compared with DTaP (1/497 doses, p < 0.001) and DT (1/359 doses, p < 0.001) recipients. High fever (< or = 40.5 degrees C) was less frequent in DTaP vaccinees (1/16,239 doses) compared with DTP (1/5,359) and DT recipients (1/4,665). One hypotonic-hyporesponsive episode was observed.

The polymerase chain reaction (PCR) was recently added to conventional culture and serology for the diagnoses of Bordetella pertussis infection in a large vaccine efficacy trial in Germany. In vaccinees or family members who had illnesses with cough, two nasopharyngeal swabs (calcium alginate for culture and Dacron for PCR) were taken and initial and follow-up clinical data were obtained. PCR was done using oligonucleotide primers PTp1 and PTp2 which amplify a 191-base pair DNA fragment of pertussis toxin operon. From December, 1993, to May, 1994, 555 pairs of swabs were processed; 28 grew B. pertussis and 9 grew B. parapertussis. Twenty-six of the 28 subjects with B. pertussis-positive cultures also had positive PCR results as did one of the 9 B. parapertussis cases and 82 additional samples were positive by PCR. PCR increased the identification of subjects with B. pertussis infections by almost 4-fold. Clinical characteristics were analyzed by laboratory category (Group 1, 28 culture-positive; Group 2, 82 culture-negative, PCR-positive; and Group 3, 436 culture- and PCR-negative). Group 1 subjects were more likely to have a diagnosis of definite or probable pertussis and to have paroxysmal cough, posttussive vomiting, whooping and a cough duration of > or = 4 weeks than Group 2 or 3 subjects. In contrast Group 2 subjects were more likely than Group 1 subjects to have had previous pertussis immunization or prior antibiotics. PCR identified many mild illnesses caused by B. pertussis that were not identified by culture.

In preparation for a large efficacy trial in Germany, a pilot study was initiated in December 1990. In this study 149 infants were enrolled; with double-blind randomization 75 received Lederle/Takeda acellular pertussis component diphtheria-tetanus-pertussis vaccine (APDT) and 74 received Lederle whole-cell pertussis component diphtheria-tetanus-pertussis vaccine (DTP). The mean age at first dose was 3.5 months, and the second and third doses followed at 6-week intervals. Reactions were relatively mild with both vaccines; in general they were less frequent following APDT. The IgG antibody responses to lymphocytosis promoting factor (LPF) and fimbriae-2 were similar in both groups whereas the responses to pertactin and filamentous haemagglutinin (FHA) were greater in APDT recipients. DTP recipients had greater responses to tetanus and diphtheria toxoids. When age of first dose was examined (8-12 weeks versus 16-20 weeks), it was found that young age had a suppressive effect on antibody responses in DTP but not APDT recipients to LPF toxoid, pertactin, fimbriae-2, and tetanus and diphtheria toxoids. High values of transplacentally acquired antibody lessened the response to LPF toxoid and tetanus toxoid in DTP recipients and to tetanus toxoid in APDT vaccinees. The IgG immune response to LPF toxoid, FHA and fimbriae-2 was found to be more uniform in APDT recipients than in DTP vaccinees. An IgA antibody response to fimbriae-2 was noted in 13% of DTP recipients but in no APDT vaccinees. The broad immunogenicity and mild reactogenicity of this APDT vaccine justifies its use in the German efficacy trial.

Between October 15 and November 18, 1985, 5 patients on a medical ward of the Albany VA Medical Center (Ward 8A) became colonized with Mycobacterium fortuitum. Because other patients in Ward 8A were at risk of developing disease with M. fortuitum, microbiologic surveillance to identify colonization in sputum was begun. By February 15, 1986, 30 colonized patients had been identified in this ward but none in another ward with a comparable patient population, which suggests a source unique to Ward 8A. Because water has been recognized as a source of opportunistic mycobacterial pathogens, we conducted a retrospective case-control study using a telephone survey questionnaire to examine a number of water exposures in 10 patients and 20 control subjects. Exposure to ice from the Ward 8A ice machine, but not to potable water, was associated with colonization with M. fortuitum. Large-volume water samples from a variety of sources were cultured for acid-fast bacilli. M. fortuitum was isolated only from the ice machine in Ward 8A. The ice machine was disconnected, and no additional patients became colonized. Although ice machines are infrequently implicated in nosocomial outbreaks, they represent a potential source for pathogens that survive or replicate in water.