Showing papers on "Vaccination published in 2005"
TL;DR: Melioidosis is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans, and the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
Abstract: Melioidosis, caused by the gram-negative saprophyte Burkholderia pseudomallei, is a disease of public health importance in southeast Asia and northern Australia that is associated with high case-fatality rates in animals and humans. It has the potential for epidemic spread to areas where it is not endemic, and sporadic case reports elsewhere in the world suggest that as-yet-unrecognized foci of infection may exist. Environmental determinants of this infection, apart from a close association with rainfall, are yet to be elucidated. The sequencing of the genome of a strain of B. pseudomallei has recently been completed and will help in the further identification of virulence factors. The presence of specific risk factors for infection, such as diabetes, suggests that functional neutrophil defects are important in the pathogenesis of melioidosis; other studies have defined virulence factors (including a type III secretion system) that allow evasion of killing mechanisms by phagocytes. There is a possible role for cell-mediated immunity, but repeated environmental exposure does not elicit protective humoral or cellular immunity. A vaccine is under development, but economic constraints may make vaccination an unrealistic option for many regions of endemicity. Disease manifestations are protean, and no inexpensive, practical, and accurate rapid diagnostic tests are commercially available; diagnosis relies on culture of the organism. Despite the introduction of ceftazidime- and carbapenem-based intravenous treatments, melioidosis is still associated with a significant mortality attributable to severe sepsis and its complications. A long course of oral eradication therapy is required to prevent relapse. Studies exploring the role of preventative measures, earlier clinical identification, and better management of severe sepsis are required to reduce the burden of this disease.
1,324 citations
Journal Article•
TL;DR: This report provides updated recommendations to improve prevention of perinatal and early childhood HBV transmission, including implementation of universal infant vaccination beginning at birth, and to increase vaccine coverage among previously unvaccinated children and adolescents.
Abstract: This report is the first of a two-part statement from the Advisory Committee on Immunization Practices (ACIP) that updates the strategy to eliminate hepatitis B virus (HBV) transmission in the United States. The report provides updated recommendations to improve prevention of perinatal and early childhood HBV transmission, including implementation of universal infant vaccination beginning at birth, and to increase vaccine coverage among previously unvaccinated children and adolescents. Strategies to enhance implementation of the recommendations include 1) establishing standing orders for administration of hepatitis B vaccination beginning at birth; 2) instituting delivery hospital policies and procedures and case management programs to improve identification of and administration of immunoprophylaxis to infants born to mothers who are hepatitis B surface antigen (HBsAg) positive and to mothers with unknown HBsAg status at the time of delivery; and 3) implementing vaccination record reviews for all children aged 11-12 years and children and adolescents aged <19 years who were born in countries with intermediate and high levels of HBV endemicity, adopting hepatitis B vaccine requirements for school entry, and integrating hepatitis B vaccination services into settings that serve adolescents. The second part of the ACIP statement, which will include updated recommendations and strategies to increase hepatitis B vaccination of adults, will be published separately.
811 citations
TL;DR: The potential mechanisms behind the variation of BCG efficacy and their implications for an improved TB vaccination strategy are discussed.
Abstract: Over the past 50 years, the Mycobacterium bovis bacille Calmette-Guerin (BCG) vaccine against tuberculosis (TB) has maintained its position as the world's most widely used vaccine, despite showing highly variable efficacy (0-80%) in different trials. The efficacy of BCG in adults is particularly poor in tropical and subtropical regions. Studies in animal models of TB, supported by data from clinical BCG trials in humans, indicate that this failure is related to pre-existing immune responses to antigens that are common to environmental mycobacteria and Mycobacterium tuberculosis. Here, we discuss the potential mechanisms behind the variation of BCG efficacy and their implications for an improved TB vaccination strategy.
727 citations
TL;DR: In this paper, a model was developed to calculate the age-specific risk of acquiring hepatitis B virus infection, acute hepatitis B (illness and death), and progression to chronic HBV infection.
Abstract: Background Limited data are available regarding global hepatitis B virus (HBV)-related morbidity and mortality and potential reduction in disease burden from hepatitis B vaccination. Methods A model was developed to calculate the age-specific risk of acquiring HBV infection, acute hepatitis B (illness and death), and progression to chronic HBV infection. HBV-related deaths among chronically infected persons were determined from HBV-related cirrhosis and hepatocellular carcinoma (HCC) mortality curves, adjusted for background mortality. The effect of hepatitis B vaccination was calculated from vaccine efficacy and vaccination series coverage, with and without administration of the first dose of vaccine within 24 h of birth (i.e. birth dose) to prevent perinatal HBV infection. Results For the year 2000, the model estimated 620,000 persons died worldwide from HBV-related causes: 580,000 (94%) from chronic infection-related cirrhosis and HCC and 40,000 (6%) from acute hepatitis B. In the surviving birth cohort for the year 2000, the model estimated that without vaccination, 64.8 million would become HBV-infected and 1.4 million would die from HBV-related disease. Infections acquired during the perinatal period, in early childhood ( or = 5 years of age accounted for 21, 48, and 31% of deaths, respectively. Routine infant hepatitis B vaccination, with 90% coverage and the first dose administered at birth would prevent 84% of global HBV-related deaths. Conclusion Globally, most HBV-related deaths result from the chronic sequelae of infection acquired in the perinatal and early childhood periods. Inclusion of hepatitis B vaccine into national infant immunization programs could prevent >80% of HBV-related deaths.
704 citations
TL;DR: The findings indicate that use of conjugate vaccine in children has substantially benefited older adults, and persons with certain comorbid conditions may benefit less than healthier persons from the indirect effects of the new vaccine.
Abstract: ContextA conjugate vaccine targeting 7 pneumococcal serotypes was licensed
for young children in 2000. In contrast to the 23-valent polysaccharide vaccine
used in adults, the 7-valent conjugate vaccine affects pneumococcal carriage
and transmission. Early after its introduction, incidence of invasive pneumococcal
disease declined among older adults, a group at high risk for pneumococcal
disease.ObjectiveTo determine among adults aged 50 years or older whether incidence of
invasive pneumococcal disease, disease characteristics, or the spectrum of
patients acquiring these illnesses have changed over the 4 years since pneumococcal
conjugate vaccine licensure.Design, Setting, and PopulationPopulation-based surveillance of invasive pneumococcal disease in 8
US geographic areas (total population, 18 813 000), 1998-2003.Main Outcome MeasuresIncidence of invasive pneumococcal disease by pneumococcal serotype
and other characteristics; frequency among case patients of comorbid conditions
and other factors influencing mortality.ResultsIncidence of invasive pneumococcal disease among adults aged 50 years
or older declined 28% (95% confidence interval [CI], −31% to −24%),
from 40.8 cases/100 000 in 1998-1999 to 29.4 in 2002-2003. Among those
aged 65 years or older, the 2002-2003 rate (41.7 cases/100 000) was lower
than the Healthy People 2010 goal (42 cases/100 000). Among adults aged
50 years or older, incidence of disease caused by the 7 conjugate vaccine
serotypes declined 55% (95% CI, −58% to −51%) from 22.4 to 10.2
cases/100 000. In contrast, disease caused by any of the 16 serotypes
only in polysaccharide vaccine did not change, and disease caused by serotypes
not in either vaccine increased somewhat, from 6.0 to 6.8 cases/100 000
(13%; 95% CI, 1% to 27%). Between 1998-1999 and 2002-2003, the proportion
of case-patients with human immunodeficiency virus infection increased from
1.7% (47/2737) to 5.6% (124/2231) (P<.001), and
those with any comorbid condition that is an indication for pneumococcal polysaccharide
vaccination increased from 62.3% (1842/2955) to 72.0% (1721/2390) (P<.001).ConclusionsOur findings indicate that use of conjugate vaccine in children has
substantially benefited older adults. However, persons with certain comorbid
conditions may benefit less than healthier persons from the indirect effects
of the new vaccine.
663 citations
TL;DR: The fragile and limited production capacity of the authors' 1950s egg-based technology for producing influenza vaccine and the lack of a national commitment to universal annual influenza vaccination mean that influenza epidemics will continue to present a substantial public health challenge.
Abstract: The fragile and limited production capacity of our 1950s egg-based technology for producing influenza vaccine and the lack of a national commitment to universal annual influenza vaccination mean that influenza epidemics will continue to present a substantial public health challenge. Dr. Michael Osterholm asks, So how can we prepare?
625 citations
TL;DR: A review of the published data on duration of immunity reveals estimates that infection-acquired immunity against pertussis disease wanes after 4–20 years and protective immunity after vaccination wanesAfter 4–12 years.
Abstract: Despite decades of high vaccination coverage, pertussis has remained endemic and reemerged as a public health problem in many countries in the past 2 decades. Waning of vaccine-induced immunity has been cited as one of the reasons for the observed epidemiologic trend. A review of the published data on duration of immunity reveals estimates that infection-acquired immunity against pertussis disease wanes after 4-20 years and protective immunity after vaccination wanes after 4-12 years. Further research into the rate of waning of vaccine-acquired immunity will help determine the optimal timing and frequency of booster immunizations and their role in pertussis control.
610 citations
TL;DR: The data suggest that these replication-competent vaccines against EBOV and MARV based on attenuated recombinant vesicular stomatitis virus vectors are safe and highly efficacious in a relevant animal model.
Abstract: Vaccines and therapies are urgently needed to address public health needs stemming from emerging pathogens and biological threat agents such as the filoviruses Ebola virus (EBOV) and Marburg virus (MARV). Here, we developed replication-competent vaccines against EBOV and MARV based on attenuated recombinant vesicular stomatitis virus vectors expressing either the EBOV glycoprotein or MARV glycoprotein. A single intramuscular injection of the EBOV or MARV vaccine elicited completely protective immune responses in nonhuman primates against lethal EBOV or MARV challenges. Notably, vaccine vector shedding was not detectable in the monkeys and none of the animals developed fever or other symptoms of illness associated with vaccination. The EBOV vaccine induced humoral and apparent cellular immune responses in all vaccinated monkeys, whereas the MARV vaccine induced a stronger humoral than cellular immune response. No evidence of EBOV or MARV replication was detected in any of the protected animals after challenge. Our data suggest that these vaccine candidates are safe and highly efficacious in a relevant animal model.
603 citations
TL;DR: Two other adverse events have been identified more recently: long-term excretion of highly evolved vaccine-derived polioviruses (VDPVs) in persons with primary immunodeficiencies, and polio outbreaks associated with circulating VDPVs in areas with low rates of OPV coverage.
Abstract: As the global eradication of wild poliovirus nears, the World Health Organization (WHO) is addressing challenges unprecedented in public health. The live, attenuated oral poliovirus vaccine (OPV), used for more than four decades to interrupt poliovirus transmission, and the vaccine of choice for developing countries, is genetically unstable. Reversion of the small number of substitutions conferring the attenuated phenotype frequently occurs during OPV replication in humans and is the underlying cause of the rare cases of vaccine-associated paralytic poliomyelitis (VAPP) in OPV recipients and their close contacts. Whereas VAPP has long been recognized, two other adverse events have been identified more recently: (a) long-term excretion of highly evolved vaccine-derived polioviruses (VDPVs) in persons with primary immunodeficiencies, and (b) polio outbreaks associated with circulating VDPVs in areas with low rates of OPV coverage. Developing a posteradication strategy to minimize the risks of VDPV emergence and spread has become an urgent WHO priority.
601 citations
01 Jan 2005
TL;DR: The history of a disease known to few people in the 21st century, the origin of smallpox as a natural dis-ease is lost in prehistory, and Edward Jenner’s work is widely regarded as the foundation of im-munology.
Abstract: (2005). Edward Jenner and the History of Smallpox and Vaccination. Baylor University Medical Center Proceedings: Vol. 18, No. 1, pp. 21-25.
593 citations
TL;DR: In long-term care facilities, where vaccination is most effective against complications, the aims of the vaccination campaign are fulfilled, at least in part, but according to reliable evidence the usefulness of vaccines in the community is modest.
TL;DR: Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens.
Abstract: Group B Streptococcus (GBS) is a multiserotype bacterial pathogen representing a major cause of life-threatening infections in newborns. To develop a broadly protective vaccine, we analyzed the genome sequences of eight GBS isolates and cloned and tested 312 surface proteins as vaccines. Four proteins elicited protection in mice, and their combination proved highly protective against a large panel of strains, including all circulating serotypes. Protection also correlated with antigen accessibility on the bacterial surface and with the induction of opsonophagocytic antibodies. Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens.
TL;DR: The vaccines developed over the first two hundred years since Jenner's lifetime have accomplished striking reductions of infection and disease wherever applied, and Pasteur's early approaches to vaccine development, attenuation and inactivation are even now the two poles of vaccine technology.
Abstract: The vaccines developed over the first two hundred years since Jenner's lifetime have accomplished striking reductions of infection and disease wherever applied. Pasteur's early approaches to vaccine development, attenuation and inactivation, are even now the two poles of vaccine technology. Today, purification of microbial elements, genetic engineering and improved knowledge of immune protection allow direct creation of attenuated mutants, expression of vaccine proteins in live vectors, purification and even synthesis of microbial antigens, and induction of a variety of immune responses through manipulation of DNA, RNA, proteins and polysaccharides. Both noninfectious and infectious diseases are now within the realm of vaccinology. The profusion of new vaccines enables new populations to be targeted for vaccination, and requires the development of routes of administration additional to injection. With all this come new problems in the production, regulation and distribution of vaccines.
TL;DR: The genotypes show a distinct geographical distribution between and even within regions, and are proving to be an invaluable tool in tracing the molecular evolution and patterns and modes of spread of hepatitis B virus.
TL;DR: This vaccine regimen can be safely given in patients undergoing radiation therapy for localized prostate cancer, with the majority of patients generating a PSA-specific cellular immune response to vaccine.
Abstract: Purpose: Many patients with clinically localized prostate cancer develop biochemical failure despite excellent local therapy perhaps due to occult metastatic disease. One potential solution is the utilization of a well-tolerated systemic therapy (e.g., vaccine) in concert with local therapy. Experimental Design:We present a randomized phase II clinical trial designed to determine if a poxviral vaccine encodingprostate-specific antig en (PSA) can induce a PSA-specific T-cell response when combined with radiotherapy in patients with clinically localized prostate cancer. Thirty patients were randomized in a 2:1 ratio into vaccine plus radiotherapy or radiotherapy- only arms. Those patients in the combination arm received a ''priming'' vaccine with recombinant vaccinia (r V) PSA plus r V containingtheT-cell costimulatory molecule B7.1 (r V-B7.1) followed by monthly booster vaccines with recombinant fowlpox PSA.The vaccines were given with local granulocyte-macrophage colony-stimulating factor andlow-dose systemicinterleukin-2. Standard external beam radiation therapy was given between the fourth and the sixth vaccinations. Results: Seventeen of 19 patients in the combination arm completed all eight vaccinations and 13 of these 17 patients had increases in PSA-specificTcells of at least 3-fold versus no detectable increases in the radiotherapy-only arm (P < 0.0005).There was also evidence ofde novo generation of T cells to well-described prostate-associated antigens not found in the vaccine, providing indirect evidence of immune-mediated tumor killing. The vaccine was well tolerated. Conclusion:This vaccine regimen can be safely given in patients undergoing radiation therapy for localized prostate cancer, with the majority of patients generating a PSA-specific cellular immune response to vaccine.
TL;DR: Strong immunological memory persists more than 10 years after immunisation of infants and adolescents with a primary course of vaccination, and booster doses of vaccine do not seem necessary to ensure long-term protection.
TL;DR: Although Eimeria are effective immunogens, it is probable that to date none of the antigens that induce potent protective immune responses during the course of natural infection has been isolated and limited progress has been achieved towards the development of subunit or recombinant vaccines.
Abstract: Studies on the biology of the avian species of Eimeria are currently benefiting from the availability of a comprehensive sequence for the nuclear genome of Eimeria tenella. Allied to some recent advances in transgenic technologies and genetic approaches to identify protective antigens, some elements are now being assembled that should be helpful for the development of a new generation of vaccines. In the meantime, control of avian coccidiosis by vaccination represents a major success in the fight against infections caused by parasitic protozoa. Live vaccines that comprise defined populations of oocysts are used routinely and this form of vaccination is based upon the long-established fact that chickens infected with coccidial parasites rapidly develop protective immunity against challenge infections with the same species. Populations of wild-type Eimeria parasites were the basis of the first live vaccines introduced around 50 years ago and the more recent introduction of safer, live-attenuated, vaccines has had a significant impact on coccidiosis control in many areas of the world. In Europe the introduction of vaccination has coincided with declining drug efficacy (on account of drug resistance) and increasing concerns by consumers about the inclusion of in-feed medication and prospects for drug residues in meat. The use of attenuated vaccines throughout the world has also stimulated a greater interest in the vaccines that comprise wild-type parasites and, during the past 3 years worldwide, around 3x10(9) doses of each type of vaccine have been used. The need for only small numbers of live parasites to induce effective protective immunity and the recognition that Eimeria spp. are generally very potent immunogens has stimulated efforts to develop other types of vaccines. None has succeeded except for the licensing, within several countries in 2002, of a vaccine (CoxAbic vaccine; Abic, Israel) that protects via the maternal transfer of immunoglobulin to the young chick. Building on the success of viral vaccines that are delivered via the embryonating egg, an in ovo coccidiosis vaccine (Inovocox, Embrex Inc.) is currently in development. Following successful field trials in 2001, the product will be ready for Food and Drug Administration approval in 2005 and a manufacturing plant will begin production for sale in late 2005. Limited progress has been achieved towards the development of subunit or recombinant vaccines. No products are available and studies to identify potential antigens remain compromised by an absence of effective in vitro assays that correlate with the induction of protective immunity in the host. To date, only a relatively small portfolio of molecules has been evaluated for an ability to induce protection in vivo. Although Eimeria are effective immunogens, it is probable that to date none of the antigens that induce potent protective immune responses during the course of natural infection has been isolated.
TL;DR: It is reported that vaccinia-specific B-cell responses are essential for protection of macaques from monkeypox virus, a variola virus ortholog, and vaccines able to induce long-lasting protective antibody responses may constitute realistic alternatives to the currently available smallpox vaccine.
Abstract: Vaccination with live vaccinia virus affords long-lasting protection against variola virus, the agent of smallpox. Its mode of protection in humans, however, has not been clearly defined. Here we report that vaccinia-specific B-cell responses are essential for protection of macaques from monkeypox virus, a variola virus ortholog. Antibody-mediated depletion of B cells, but not CD4+ or CD8+ T cells, abrogated vaccine-induced protection from a lethal intravenous challenge with monkeypox virus. In addition, passive transfer of human vaccinia-neutralizing antibodies protected nonimmunized macaques from severe disease. Thus, vaccines able to induce long-lasting protective antibody responses may constitute realistic alternatives to the currently available smallpox vaccine (Dryvax).
TL;DR: The recent discovery of natural immunity to the hepatitis C virus and vaccine efficacy in the chimpanzee challenge model has allowed optimism about the development of at least a partly effective vaccine against this heterogeneous pathogen.
Abstract: The recent discovery of natural immunity to the hepatitis C virus and vaccine efficacy in the chimpanzee challenge model has allowed optimism about the development of at least a partly effective vaccine against this heterogeneous pathogen that is responsible for much of the chronic liver disease around the world. The immune systems of some infected individuals can spontaneously clear the virus, whereas other people need treatment with antivirals that work partly by stimulating humoral and cellular immune responses. Therefore, therapeutic vaccine strategies are also being pursued to improve treatment outcome.
TL;DR: Combination immunotherapy consisting of a single early post-transplant infusion of in vivo vaccine-primed and ex vivo costimulated autologous T cells followed by post-Transplant booster immunizations improved the severe immunodeficiency associated with high-dose chemotherapy and led to the induction of clinically relevant immunity in adults within a month after transplantation.
Abstract: Immunodeficiency is a barrier to successful vaccination in individuals with cancer and chronic infection. We performed a randomized phase 1/2 study in lymphopenic individuals after high-dose chemotherapy and autologous hematopoietic stem cell transplantation for myeloma. Combination immunotherapy consisting of a single early post-transplant infusion of in vivo vaccine-primed and ex vivo costimulated autologous T cells followed by post-transplant booster immunizations improved the severe immunodeficiency associated with high-dose chemotherapy and led to the induction of clinically relevant immunity in adults within a month after transplantation. Immune assays showed accelerated restoration of CD4 T-cell numbers and function. Early T-cell infusions also resulted in significantly improved T-cell proliferation in response to antigens that were not contained in the vaccine, as assessed by responses to staphylococcal enterotoxin B and cytomegalovirus antigens (P < 0.05). In the setting of lymphopenia, combined vaccine therapy and adoptive T-cell transfer fosters the development of enhanced memory T-cell responses.
TL;DR: The goal of this work is to provide an overview of the cellular and molecular factors involved in the induction of immunity and how such factors may influence the potency of an adjuvant or a vaccine.
TL;DR: Using a stochastic simulation model of influenza transmission, clinical illness, and economic costs, the population-wide benefits of routinely vaccinating US children against influenza are estimated.
TL;DR: In addition to providing direct protection to vaccine recipients, killed oral cholera vaccines confer significant herd protection to neighbouring non-vaccinated individuals.
TL;DR: Human serum samples after immunization with MF59 or nonadjuvanted A/duck/Singapore/97 (H5N3) vaccine were tested for antibody to 1997-2004 human H5N1 viruses and findings have implications for the rational design of pandemic vaccines against influenza H5.
Abstract: Antigenically well-matched vaccines against highly pathogenic avian influenza H5N1 viruses are urgently required. Human serum samples after immunization with MF59 or nonadjuvanted A/duck/Singapore/97 (H5N3) vaccine were tested for antibody to 1997-2004 human H5N1 viruses. Antibody responses to 3 doses of nonadjuvanted vaccine were poor and were higher after MF59-adjuvanted vaccine, with seroconversion rates to A/HongKong/156/97, A/HongKong/213/03, A/Thailand/16/04, and A/Vietnam/1203/04 of 100% (P < .0001), 100% (P < .0001), 71% (P = .0004), and 43% (P = .0128) in 14 subjects, respectively, compared with 27%, 27%, 0%, and 0% in 11 who received nonadjuvanted vaccine. These findings have implications for the rational design of pandemic vaccines against influenza H5.
TL;DR: Data is reported on the persistence of antibodies to hepatitis B surface antigen (anti-HBs), incidence of HBV infection, and the genetic characteristics of the HBV isolates in persons with breakthrough infections 15 years after initial vaccination of this cohort.
Abstract: The duration of protection afforded by hepatitis B vaccination is unknown. In this cohort of Alaska Natives who received vaccination against hepatitis, antibody levels decreased over a 15-year peri...
TL;DR: Protection against challenge was T cell-dependent and substantially more potent than DNA vaccination alone, and gene-based vaccination with NP may contribute to protective immunity against diverse influenza viruses through its ability to stimulate cellular immunity.
TL;DR: It is found that MMR vaccination is most unlikely to be a main cause of autism spectrum disorders, that it cannot explain the rise over time in the incidence of ASD, and that withdrawal of MMR in countries where it is still being used cannot be expected to lead to a reduction in the frequency of ASD.
Abstract: Background: A causal relationship between the measles, mumps, and rubella (MMR) vaccine and occurrence of autism spectrum disorders (ASD) has been claimed, based on an increase in ASD in the USA and the UK after introduction of the MMR vaccine. However, the possibility that this increase is coincidental has not been eliminated. The unique circumstances of a Japanese MMR vaccination program provide an opportunity for comparison of ASD incidence before and after termination of the program. Methods: This study examined cumulative incidence of ASD up to age seven for children born from 1988 to 1996 in Kohoku Ward (population approximately 300,000), Yokohama, Japan. ASD cases included all cases of pervasive developmental disorders according to ICD-10 guidelines. Results: The MMR vaccination rate in the city of Yokohama declined significantly in the birth cohorts of years 1988 through 1992, and not a single vaccination was administered in 1993 or thereafter. In contrast, cumulative incidence of ASD up to age seven increased significantly in the birth cohorts of years 1988 through 1996 and most notably rose dramatically beginning with the birth cohort of 1993. Conclusions: The significance of this finding is that MMR vaccination is most unlikely to be a main cause of ASD, that it cannot explain the rise over time in the incidence of ASD, and that withdrawal of MMR in countries where it is still being used cannot be expected to lead to a reduction in the incidence of ASD.
TL;DR: Animal models of immune enhancement permit a deep understanding of the role of specific immune responses in RSV disease, assist in vaccine design, and indicate which immunomodulatory therapy might be beneficial to children with bronchiolitis.
Abstract: Respiratory syncytial virus (RSV) is one of the commonest and most troublesome viruses of infancy. It causes most cases of bronchiolitis, which is associated with wheezing in later childhood. In primary infection, the peak of disease typically coincides with the development of specific T- and B-cell responses, which seem, in large part, to be responsible for disease. Animal models clearly show that a range of immune responses can enhance disease severity, particularly after vaccination with formalin-inactivated RSV. Prior immune sensitization leads to exuberant chemokine production, an excessive cellular influx, and an overabundance of cytokines during RSV challenge. Under different circumstances, specific mediators and T-cell subsets and antibody-antigen immune complex deposition are incriminated as major factors in disease. Animal models of immune enhancement permit a deep understanding of the role of specific immune responses in RSV disease, assist in vaccine design, and indicate which immunomodulatory therapy might be beneficial to children with bronchiolitis.
TL;DR: The Gambian Hib immunisation programme reduced the occurrence of Hib disease despite irregular vaccine supply, and has important implications for the introduction of the vaccine into routine immunisation programmes of other developing countries.
TL;DR: More than 1 in 3 children were undervaccinated for more than 6 months during their first 24 months of life and 1 in 4 children were delayed for at least 4 vaccines.
Abstract: ContextOnly 18% of children in the United States receive all vaccinations at
the recommended times or acceptably early.ObjectiveTo determine the extent of delay of vaccination during the first 24
months of life.Design, Setting, and ParticipantsThe 2003 National Immunization Survey was conducted by random-digit
dialing of households and mailings to vaccination providers to estimate vaccination
coverage rates for US children aged 19 to 35 months. Data for this study were
limited to 14 810 children aged 24 to 35 months.Main Outcome MeasuresCumulative days undervaccinated during the first 24 months of life for
each of 6 vaccines (diphtheria and tetanus toxoids and acellular pertussis;
poliovirus; measles, mumps, and rubella; Haemophilus influenzae type b; hepatitis B; and varicella) and all vaccines combined, number
of late vaccines, and risk factors for severe delay of vaccination.ResultsChildren were undervaccinated a mean of 172 days (median, 126 days)
for all vaccines combined during their first 24 months of life. Approximately
34% were undervaccinated for less than 1 month and 29% for 1 to 6 months,
while 37% were undervaccinated for more than 6 months. Vaccine-specific undervaccination
of more than 6 months ranged from 9% for poliovirus vaccine to 21% for Haemophilus influenzae type b vaccine. An estimated 25%
of children had delays in receipt of 4 or more of the 6 vaccines. Approximately
21% of children were severely delayed (undervaccinated for more than 6 months
and for ≥4 vaccines). Factors associated with severe delay included having
a mother who was unmarried or who did not have a college degree, living in
a household with 2 or more children, being non-Hispanic black, having 2 or
more vaccination providers, and using public vaccination provider(s).ConclusionsMore than 1 in 3 children were undervaccinated for more than 6 months
during their first 24 months of life and 1 in 4 children were delayed for
at least 4 vaccines. Standard measures of vaccination coverage mask substantial
shortfalls in ensuring that recommendations are followed regarding age at
vaccination throughout the first 24 months of life.