Effectiveness of hospital-based postpartum procedures on pertussis vaccination among postpartum women.

OBJECTIVE: Pertussis causes significant morbidity among adults, children, and especially infants. Since 2006, pertussis vaccination has been recommended for women after delivery. We conducted a prospective, controlled evaluation of in-hospital postpartum pertussis vaccination of birth mothers from October 2009 through July 2010 to evaluate the effectiveness of hospital-based procedures in increasing postpartum vaccination. STUDY DESIGN: The intervention and comparison hospitals are private community facilities, each with 2000-6000 births/year. At the intervention hospital, physician opt-in orders for tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Tdap) before discharge were implemented in November 2009, followed by standing orders in February 2010. The comparison hospital maintained standard practice. Randomly selected hospital charts of women after delivery were reviewed for receipt of Tdap and demographic data. We evaluated postpartum Tdap vaccination rates and conducted multivariate analyses to evaluate characteristics that are associated with vaccination. We reviewed 1264 charts (658 intervention hospital; 606 comparison hospital) from women with completed deliveries. RESULTS: Tdap postpartum vaccination was 0% at both hospitals at baseline. In the intervention hospital, the introduction of the opt-in order was followed by an increase in postpartum vaccination to 18%. The introduction of the standing order approach was followed by a further increase to 69% (P < .0001). No postpartum Tdap vaccinations were documented in the comparison hospital. Postpartum Tdap vaccination in the intervention hospital did not differ by demographic characteristics. CONCLUSION: In-hospital ordering procedures substantially increased Tdap vaccination coverage in women after delivery. Opt-in orders increased coverage that increased substantially with standing orders.

Shift in the epidemiology of pertussis infection: an indication for pertussis vaccine boosters for adults?

Pertussis vaccination of young children has been effective in reducing the overall disease burden due to Bordetella pertussis in many countries. However, the disease has not been eliminated, although humans are the only known host of this pathogen. In fact, in some countries, the number of reported cases has increased dramatically from their nadir and epidemics routinely occur. In areas where >80% of children <2 years of age have been vaccinated, the burden of disease has shifted from elementary school-aged children (who are presumably protected by vaccination) to young infants (<6 months of age) and individuals >11 years of age. With the recent availability of acellular pertussis vaccines for older children to adults, consideration of a change in current vaccination policy is necessary in order to provide better disease control.

Adverse events reported following live, cold-adapted, intranasal influenza vaccine.

CONTEXT: In June 2003, the US Food and Drug Administration licensed a trivalent live, attenuated influenza vaccine (LAIV-T) for intranasal administration to healthy persons 5 to 49 years of age. Although prelicensure testing involved 20 228 vaccinees, clinical trials were not of sufficient size to detect rare adverse events reliably. OBJECTIVE: To identify adverse events reported following LAIV-T administration after licensure. DESIGN, SETTING, AND PARTICIPANTS: All adverse events reported to the US Vaccine Adverse Event Reporting System (VAERS) during the 2003-2004 and the 2004-2005 influenza seasons. MAIN OUTCOME MEASURES: Numbers and proportions of reported adverse events and reporting rates of adverse events per 100,000 vaccinees. RESULTS: Approximately 2,500,000 persons received LAIV-T during the first 2 postlicensure seasons. As of August 16, 2005, VAERS received 460 adverse event reports for vaccinations received from August 2003 through July 2005. No fatalities were reported. There were 7 reports of possible anaphylaxis, 2 reports of Guillain-Barré syndrome, 1 report of Bell palsy, and 8 reports of asthma exacerbation among individuals with a prior asthma history. Events in individuals for whom the vaccine was not indicated accounted for 73 reports (16%). CONCLUSIONS: Reports to VAERS 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. Like many vaccines and other medical products, LAIV-T may rarely cause anaphylaxis. Secondary transmission of the vaccine virus merits further investigation. Reports of asthma exacerbations in vaccinees with prior asthma history highlight the risks of vaccine use inconsistent with approved labeling.

Safety and immunogenicity of haemophilus influenzae type B polysaccharide or conjugate vaccines in an elderly adult population.

OBJECTIVES: To evaluate the safety and immunogenicity of unconjugated Haemophilus influenzae type b (Hib) polysaccharide (PRP) vaccine and two PRP-protein-conjugated vaccines as a model for the comparison of protein-conjugated versus plain polysaccharide vaccines in the elderly. DESIGN: Randomized, double-blind, prospective study. SETTING: University-based center for vaccine research and development. PARTICIPANTS: A total of 125 adults, aged 64 to 92, who were judged to be in general good health and lacking any significant underlying medical conditions. INTERVENTION: Subjects were randomized to receive one of three vaccines: Group 1 (n=39), PRP; Group 2 (n=44), PRP conjugated to an outer-membrane protein complex of Neisseria meningitidis (PRP-OMP); and Group 3 (n=42), PRP conjugated to diphtheria toxoid (PRP-D). Sera were obtained before immunization and 1 and 12 months later. MEASUREMENTS: Subjects maintained a diary of injection site and systemic reactions for 3 days after immunization. A radioantigen-binding assay was used to measure total concentrations of serum anticapsular antibody, and an enzyme-linked immunosorbent assay was used to measure immunoglobulin (Ig) G1 and IgG2 anticapsular antibody responses. Antibody functional activity was assessed using a complement-mediated bactericidal assay. RESULTS: Before vaccination, the geometric mean serum anticapsular antibody concentration was 0.8 microg/mL, but fewer than 10% of subjects had detectable bactericidal activity (titer>1:4). The magnitude, subclass distribution, and bactericidal activity of antibody responses to unconjugated PRP vaccine were similar to those observed in previous studies of younger adults immunized with PRP. The OMP conjugate, which is highly immunogenic after one dose in 2-month old infants, did not elicit anticapsular antibody responses in the elderly greater than those elicited by PRP vaccine (P=.43). In contrast, the D conjugate, which is poorly immunogenic in 2-month old infants, elicited higher anticapsular antibody responses than PRP vaccine in the elderly (P=.01) and higher levels than the OMP-conjugate 1 year after vaccination (P<.006). CONCLUSION: Elderly adults develop protective anticapsular antibody responses to unconjugated and conjugated PRP vaccine. The higher anticapsular antibody responses to the D conjugate but not to the OMP conjugate in the elderly, which is the reverse of that observed in immunized infants, implies fundamental differences in the immunological mechanisms by which the two age groups respond to PRP and by which the OMP and D conjugates elicit anticapsular antibody responses.

Pertussis in adolescents and its prevention using Tdap vaccination.

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.

Safety and immunogenicity of inactivated, Vero cell culture-derived whole virus influenza A/H5N1 vaccine given alone or with aluminum hydroxide adjuvant in healthy adults.

Dosage-sparing strategies, adjuvants and alternative substrates for vaccine production are being explored for influenza vaccine development. We assessed the safety and immunogenicity of a Vero cell culture-grown inactivated whole virus influenza A/H5N1 vaccine with or without aluminum hydroxide adjuvant [Al(OH)(3)] in healthy young adults. Vaccines were well tolerated, but injection site discomfort was more frequent in groups receiving Al(OH)(3). Dose-related increases in serum antibody levels were observed. Neutralizing antibody titers varied significantly when tested by two different laboratories. Al(OH)(3) did not enhance HAI or neutralizing antibody responses, and contributed to increased injection site pain. Because influenza antibody titers vary significantly between different laboratories, international standardization of assays is warranted.