Acellular Pertussis Vaccines (acellular + pertussis_vaccine)

Distribution by Scientific Domains


Selected Abstracts


Knowledge, Attitude, and Practices With Regard to Adult Pertussis Vaccine Booster in Travelers

JOURNAL OF TRAVEL MEDICINE, Issue 3 2007
Annelies Wilder-Smith MD, FAMS
Introduction Pertussis is a worldwide, highly communicable, vaccine-preventable respiratory disease and is a frequent but often underestimated cause of prolonged cough illness in adults. Immunity from childhood pertussis immunization is thought to last only up to 10 years. The incidence of adult pertussis has been estimated to be 200 to 500 per 100,000 persons-years. Acellular pertussis vaccines have been evaluated in adults and confer safe and effective protection and now exist as combination vaccine together with tetanus and diphtheria. Methods We did a questionnaire survey to assess the knowledge, attitude, and practices toward pertussis in adult travelers. We consecutively enrolled all travelers who presented at the Travellers' Health & Vaccination Centre in Singapore in 1 month. Results Of 218 consecutively enrolled travelers, 184 (84.4%) completed the questionnaire; of which 80% were Singaporeans. Seventy persons (38%) did not know or gave a wrong answer for the mode of transmission of pertussis, 147 (83%) had never heard of a pertussis vaccine for adults, and almost none had received an adult pertussis vaccine booster. Travelers from Western countries were seven times [95% confidence interval (CI): 2,27] more likely than Asians to have knowledge about pertussis; women were 4.27 times (95% CI: 1.59,11.53) more likely than men to be aware of the booster vaccine, after adjusting for nationality ( p= 0.004). Conclusions Knowledge about pertussis was poor among adult travelers. Although pertussis was viewed as a serious illness by the majority of participants, and 38% expressed the desire to be vaccinated, almost no one had received the pertussis vaccine booster. Awareness about pertussis, its risks, and prevention via vaccination need to be increased among adult travelers. Studies are needed to quantify the risk of pertussis in adult travelers. [source]


Adverse reactions to immunization with newer vaccines in the very preterm infant

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 8 2005
Vanessa J Ellison
Objective: To study the frequency and types of adverse reactions to currently available vaccines in very preterm infants. Methods: Case notes were obtained for very preterm infants ,30 weeks' gestational age who received their first immunization at the Royal Women's Hospital, Melbourne, during 1999,2003. Data were extracted for the time periods 48 h before and 48 h after immunizations, with the data extraction blinded as to whether the period being evaluated was pre- or post-immunization. Data collected focused on the frequency and severity of apnoea, respiratory support, fever and clinical consequences of adverse reactions. Results: A total of 48 very preterm infants were immunized during the period; 37 infants had Comvax (Haemophilus influenzae type B and hepatitis B vaccine), Infanrix (diphtheria, tetanus and acellular pertussis vaccine) and inactivated poliomyelitis vaccine, and 11 infants had Comvax and Infanrix only. Their mean (SD) gestational age at birth was 26.4 (1.7) weeks with mean birthweight of 872 (235) g. The mean postnatal age at immunization was 76 (20) days. Low-grade fever (>37.5°C per axilla) occurred in 16 (33%) infants after immunization, but none before immunization (P < 0.001). There was no substantial change in recorded apnoea. No serious adverse events were noted. Four (8%) infants underwent a septic work up post-immunization. The C-reactive protein was increased in all four infants, but other tests for sepsis were negative. Conclusion: Fever remains a common adverse event following immunization of the preterm infant in spite of the development of a new generation of vaccines. [source]


Kinetics and sensitivity of ELISA IgG pertussis antitoxin after infection and vaccination with Bordetella pertussis in young children

APMIS, Issue 11 2009
HANS O. HALLANDER
Sera from 96 young children in a vaccine trial were analysed for kinetics of ELISA IgG anti-pertussis toxin (anti-PT) after a laboratory-verified pertussis infection. The antibody decay curves after infection were biphasic and similar in shape to those after vaccination. The change from a rapid to a slower decay after the peak occurred about 4,5 months from the first day of cough. In a group of children given a two- or a five-component acellular pertussis vaccine the proportion of sera above the tentative cut-off values for anti-PT of 20, 50 or 100 EU/ml 12 months after onset of the infection were 19%, 0% and 0% respectively. Corresponding figures for a whole-cell or placebo vaccine group of infected children were significantly higher, 73%, 39% and 30%, i.e. the antibody decay after infection in young children depends on vaccination status as well as on the pertussis vaccine given. In a large group of non-infected children vaccinated with the same five-component acellular vaccine 13%, 0% and 0% had sera above 20, 50 and 100 EU/ml at 12 months after the third vaccine dose and all were below the minimum level of detection 2 years after vaccination. In conclusion, knowledge about anti-PT kinetics is essential for the interpretation of seroepidemiological data but hardly offers the possibility to establish valid cut-off values for anti-PT in single sample serology. An option would be to identify a grey zone between the positive and negative ends of the distribution for follow-up testing by a second serum. [source]


Evaluation of efficacy in terms of antibody levels and cell-mediated immunity of acellular pertussis vaccines in a murine model of respiratory infection

FEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2002
Mineo Watanabe
Abstract The efficacy of six acellular pertussis vaccines, prepared by various manufacturers in Japan, was investigated in a murine model of respiratory infection (aerosol challenge model) and a murine intracerebral (i.c.) challenge model. There was a good correlation between bacterial clearance from the lungs after aerosol challenge and the potency of vaccines as determined by i.c. challenge. The levels of antibodies against filamentous hemagglutinin were higher after immunizations with all tested vaccines than the levels of antibodies against pertussis toxin and pertactin. Spleen cells from mice immunized with each individual vaccine secreted interferon , (IFN-,) in response to stimulation by pertussis toxin, filamentous hemagglutinin and fimbriae. The production of interleukin-4 in response to each of the antigens tested was detected but was lower than that of IFN-,. However, antibody levels and cell-mediated immune responses were not correlated with the protective effects of the vaccines after aerosol challenge and after i.c. challenge. [source]


Changes of the Swedish Bordetella pertussis population in incidence peaks during an acellular pertussis vaccine period between 1997 and 2004,

APMIS, Issue 4 2007
ABDOLREZA ADVANI
In a surveillance programme undertaken from 1997 through 2004, Bordetella pertussis isolates and clinical information were collected after introduction of acellular pertussis vaccines (Pa) in 1996. Changes in the B. pertussis population were studied in three incidence peaks: 1999,2000, 2002 and 2004. Available isolates from 158 fully vaccinated children representing all of Sweden, plus 37 from the Gothenburg area 2003,2004, were analysed by pulsed-field gel electrophoresis (PFGE), serotyping and sequencing of the virulence factor genes pertussis toxin subunits 1 and 3 (ptxA, ptxC), pertactin (prn), tracheal colonisation factor (tcfA) and fimbria3 (fim3). Allele ptxA1 was found in all isolates. There was a statistically significant increasing trend in three out of five studied genes, ptxC, prn and tcfA, and for a fourth, Fim3, if Gothenburg strains were included. The PFGE profile BpSR11 appearing in the 1999,2000 peak dominated by ,23% during the entire period, bringing with it the allele combination 1/2/2/2/B (ptxA1/ptxC2/prn2/tcfA2/fim3B). Other BpSR11-related profiles with the same allele combination and more than 82% similarity,BpSR5 in the 2002 peak and BpSR12 in the 2004 peak,appeared with an increasing trend. Although vaccination with Pa has reduced disease, new variants have emerged representing clones surviving in the immunized population. [source]