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1.
Euro Surveill ; 19(9)2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24626207

RESUMO

During the 2013/14 influenza season in Canada, 631 of 654 hospitalisations for laboratory-confirmed influenza enrolled in sentinel hospitals were due to Influenza A. Of the 375 with known subtype, influenza A(H1N1) accounted for 357. Interim unmatched vaccine effectiveness adjusted for age and presence of one or more medical comorbidities was determined by test-negative case-control design to be 58.5% (90% confidence interval (CI): 43.9-69.3%) overall and 57.9% (90% CI: 37.7-71.5) for confirmed influenza A(H1N1).


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Avaliação de Resultados em Cuidados de Saúde , Vigilância de Evento Sentinela , Adolescente , Adulto , Idoso , Canadá/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Laboratórios , Masculino , Pessoa de Meia-Idade , Estações do Ano , Índice de Gravidade de Doença , Adulto Jovem
2.
Eur J Clin Microbiol Infect Dis ; 31(4): 591-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21796343

RESUMO

We aimed to assess the immunogenicity of a single half-dose of AS03-adjuvanted monovalent 2009 pandemic H1N1 vaccine in healthy adults. Healthy subjects age 20-60 years were prospectively enrolled in a cohort receiving intramuscular administration of a single half-dose (1.875 µg of hemagglutinin [HA]) of adjuvanted 2009 pandemic H1N1 influenza vaccine. Data from participants enrolled in a concomitant study of immunogenicity following a full-dose (3.75 µg of HA) are presented concurrently. Sera for assessment of hemagglutination-inhibiting (HAI) antibody to the vaccine strain were obtained before and 14 or 21 days after vaccination. Ninety-seven participants received a half-dose and 50 received a full-dose of vaccine. In the half-dose cohort, Food and Drug Administration criteria for immunogenicity regarding seroprotection and seroconversion rates were met for subjects aged 20-45 years, but not for those aged 46-60 years. There was no statistically significant difference in the proportion of individuals achieving a post-vaccination HAI titre of ≥1:40, the geometric mean titres of post-vaccination antibody, or the proportion of individuals with a four-fold or greater increase in antibody levels between the two cohorts. Participants 46-60 years of age were significantly less likely to be seroprotected at day 21 than those 20-45 years old in both cohorts. Immunogenicity of a half dose of adjuvanted pH1N1 influenza vaccine was adequate in subjects aged 20-45 years. Dose reduction is a possible strategy for expanding the availability in the event of vaccine shortage in this age group.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Adulto , Fatores Etários , Anticorpos Antivirais/sangue , Estudos de Coortes , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
3.
Pediatr Infect Dis J ; 41(4): e166-e171, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35093996

RESUMO

BACKGROUND: Invasive pneumococcal disease due to Streptococcus pneumoniae can cause mortality and severe morbidity due to sepsis, meningitis and pneumonia, particularly in young children and the elderly. Recurrent invasive pneumococcal disease is rare yet serious sequelae of invasive pneumococcal disease that is associated with the immunocompromised and leads to a high mortality rate. METHOD: This retrospective study reviewed recurrent invasive pneumococcal disease cases from the Canadian Immunization Monitoring Program, ACTive (IMPACT) between 1991 and 2019, an active network for surveillance of vaccine-preventable diseases and adverse events following immunization for children ages 0-16 years. Data were collected from 12 pediatric tertiary care hospitals across all 3 eras of public pneumococcal conjugate vaccine implementation in Canada. RESULTS: The survival rate within our cohort of 180 recurrent invasive pneumococcal disease cases was 98.3%. A decrease of 26.4% in recurrent invasive pneumococcal disease due to vaccine serotypes was observed with pneumococcal vaccine introduction. There was also a 69.0% increase in the rate of vaccination in children with preexisting medical conditions compared with their healthy peers. CONCLUSION: The decrease in recurrent invasive pneumococcal disease due to vaccine-covered serotypes has been offset by an increase of non-vaccine serotypes in this sample of Canadian children.


Assuntos
Infecções Pneumocócicas , Adolescente , Idoso , Canadá/epidemiologia , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Estudos Retrospectivos , Vacinação/efeitos adversos , Vacinas Conjugadas
4.
Clin Infect Dis ; 53(9): 885-92, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21946190

RESUMO

BACKGROUND: Because adolescents and adults act as a primary source of pertussis infection for infants, vaccination of mothers immediately postpartum is a potential strategy to reduce transmission (cocoon strategy). For this to be effective, high levels of antibodies must be achieved rapidly after vaccination. We sought to determine whether the antibody response to tetanus-diphtheria-acellular pertussis vaccine (Tdap) is sufficiently rapid to support the cocoon strategy. METHODS: Two sequential studies were performed. The first was a nonrandomized, open study of a 5-pertussis-component Tdap vaccine (tetanus toxoid, diphtheria toxoid, pertussis toxoid [PT], filamentous hemagglutinin [FHA], fimbriae types 2 and 3 [FIM], and pertactin [PRN]) given to women of childbearing age; the second was a randomized, open study of Tdap or no vaccine in postpartum women. Serum levels of immunoglobin (Ig) G and IgA against pertussis antigens, serum levels of IgG against diphtheria and tetanus, and breast milk levels of IgA against pertussis antigens were measured at various times after vaccination. RESULTS: In both studies, the antibody response was relatively rapid, with serum IgG and IgA levels beginning to increase noticeably by days 5-7 and approaching peak levels by day 14. Greater than 68% and 84.4% of IgG and IgA responders, respectively, achieved ≥ 90% of their maximum titer by day 14. The diphtheria and tetanus antibody kinetics followed a similar time course. Breast milk levels of IgA against PT, FHA, and FIM were first detectable at day 7, peaked by day 10, and then slowly decreased through day 28. Antibodies against PRN showed a similar response, although the peak occurred at day 14. There were no significant antibody responses in the control group. CONCLUSIONS: Although the antibody response to a dose of Tdap in healthy nonpregnant women of child-bearing age and postpartum women occurs by day 14 and is suggestive of an anamnestic immune response, it may not be sufficiently rapid to protect infants in the first weeks of life.


Assuntos
Anticorpos Antibacterianos/sangue , Vacinas contra Difteria, Tétano e Coqueluche Acelular/administração & dosagem , Vacinas contra Difteria, Tétano e Coqueluche Acelular/imunologia , Adolescente , Adulto , Sangue/imunologia , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina G/sangue , Leite Humano/imunologia , Período Pós-Parto , Adulto Jovem
5.
Hum Vaccin Immunother ; 17(9): 3052-3065, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33988486

RESUMO

Vaccine coverage is below desired levels in Canada, despite National Advisory Committee on Immunization recommendations. One solution to improve coverage is to offer vaccines in pharmacies. We explore the awareness, attitudes, beliefs, and behaviors of the general public in four communities in Nova Scotia (NS) and New Brunswick (NB) about the changing role of pharmacists as immunizers. Adult members of the public were invited to complete an online survey through advertisements in print and online, and through e-mail lists at local universities. Immunization status among participants (n = 985) varied across vaccines with slightly more than one-half of the participants (51.8%) reporting receipt of a seasonal influenza vaccine last year, 38.0% reporting receipt of the meningococcal C or ACWY vaccine, and 77.7% reporting receipt of the pertussis vaccine. Despite variable self-reported receipt of vaccines, the pervasive belief that participants were not at risk of getting vaccine-preventable diseases, and a lack of awareness about which vaccines are recommended for adults, participants in this study held vaccine-positive beliefs. Participants, especially those who had previously been vaccinated in a pharmacy (39.0%), were supportive of the inclusion of pharmacists as immunizers although nearly one-half of the participants would feel more comfortable getting vaccinated by a pharmacist if another practitioner recommended it to them. While cost threatens to be a barrier to pharmacists as immunizers, this study suggests that they are well-positioned to improve vaccine coverage and to communicate recommendations and other vaccine-related information to the public.


Assuntos
Vacinas contra Influenza , Farmacêuticos , Adulto , Atitude , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Nova Escócia , Vacinação
6.
Eur J Clin Microbiol Infect Dis ; 29(3): 259-67, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20033465

RESUMO

With the emergence of multiple meningococcal serogroups in different geographic areas, broad vaccine protection from infancy is desirable. One hundred and seventy-five infants received either two doses of a meningococcal quadrivalent (A, C, W-135, Y) conjugate vaccine (MenACWY-CRM) at 6 and 12 months, one dose of MenACWY-CRM at 12 months, or MenC at 12 months and MenACWY-CRM at 18 months. Bactericidal antibody titers using human complement were measured before and 1 month after each dose. Injection-site reactions were reported by 22-45% of participants following MenACWY-CRM given at 6 or 12 months. Similar proportions of subjects had injection-site reactions following two doses of MenACWY-CRM (32-41%) or one dose of MenC (26-44%). The incidence of systemic adverse events was comparable between groups. After two doses of MenACWY-CRM, the percentages of participants reporting hSBA titers >or=8 were 100% for C, W-135, and Y, and 84% for A. Serogroup C titers were more than 10-fold higher after two doses of MenACWY-CRM than after one dose of MenC or MenACWY-CRM at 12 months. Serogroup C titers were comparable following a single dose of MenACWY-CRM or MenC at 12 months. MenACWY-CRM is well tolerated and immunogenic given at 12 months, or two doses at 6 and 12 months of age.


Assuntos
Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/imunologia , Neisseria meningitidis/imunologia , Análise de Variância , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Esquema de Medicação , Feminino , Humanos , Lactente , Masculino , Infecções Meningocócicas/imunologia , Vacinas Meningocócicas/administração & dosagem , Vacinas Meningocócicas/efeitos adversos , Teste Bactericida do Soro , Vacinação , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/efeitos adversos , Vacinas Conjugadas/imunologia
7.
J Med Microbiol ; 69(2): 256-264, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31264957

RESUMO

Background. The Serious Outcomes Surveillance Network of the Canadian Immunization Research Network (CIRN SOS) has been performing active influenza surveillance since 2009 (ClinicalTrials.gov identifier: NCT01517191). Influenza A and B viruses are identified and characterized using real-time reverse-transcriptase polymerase chain reaction (RT-PCR), and multiplex testing has been performed on a subset of patients to identify other respiratory virus aetiologies. Since both methods can identify influenza A and B, a direct comparison was performed.Methods. Validated real-time RT-PCRs from the World Health Organization (WHO) to identify influenza A and B viruses, characterize influenza A viruses into the H1N1 or H3N2 subtypes and describe influenza B viruses belonging to the Yamagata or Victoria lineages. In a subset of patients, the Seeplex RV15 One-Step ACE Detection assay (RV15) kit was also used for the detection of other respiratory viruses.Results. In total, 1111 nasopharyngeal swabs were tested by RV15 and real-time RT-PCRs for influenza A and B identification and characterization. For influenza A, RV15 showed 98.0 % sensitivity, 100 % specificity and 99.7 % accuracy. The performance characteristics of RV15 were similar for influenza A subtypes H1N1 and H3N2. For influenza B, RV15 had 99.2 % sensitivity, 100 % specificity and 99.8 % accuracy, with similar assay performance being shown for both the Yamagata and Victoria lineages.Conclusions. Overall, the detection of circulating subtypes of influenza A and lineages of influenza B by RV15 was similar to detection by real-time RT-PCR. Multiplex testing with RV15 allows for a more comprehensive respiratory virus surveillance in hospitalized adults, without significantly compromising the reliability of influenza A or B virus detection.


Assuntos
Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Adulto , Canadá/epidemiologia , Feminino , Hospitalização , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Vírus da Influenza B/classificação , Vírus da Influenza B/genética , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Influenza Humana/terapia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
8.
Scand J Immunol ; 69(4): 351-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19284500

RESUMO

The oral commensal bacterium Streptococcus gordonii has been gathering interest as a candidate live mucosal vaccine delivery vector. S. gordonii has been shown to be capable of activating antigen presenting immune cells in a manner which leads to their activation and maturation, yet the mechanism used by S. gordonii to do so is poorly understood. The aim of this work was to investigate the immunostimulatory components of S. gordonii in inducing murine dendritic cell (DC) activation and maturation. Lipoteichoic acid (LTA), lipoprotein (LP), peptidoglycan (PGN), and DNA were isolated from S. gordonii, and used to stimulate murine DC. Cytokine production and DC surface marker upregulation in response to the bacterial components was quantified by enzyme-linked immunosorbent assay and flow cytometry respectively. The results were contrasted against data obtained from DC derived from MyD88, TRIF [TIR(Toll/Interleukin-1 Receptor)-domain-containing adapter-inducing interferon-beta] or toll-like receptor-2 (TLR-2) knockout mice. The four S. gordonii bacterial components were found to differentially induce cytokine production and surface marker upregulation by murine DC. Activation of DC by both whole S. gordonii cells and the four bacterial components was abrogated in the absence of MyD88, but not in the absence of TRIF. LTA, LP and PGN, but not DNA and whole S. gordonii, required TLR-2 to induce a DC response. The results collectively indicate that S. gordonii activates DC predominantly through a MyD88-dependent and TRIF-independent pathway. This activation can be attributed to multiple immunostimulatory components present within S. gordonii bacterial cells.


Assuntos
Antígenos de Bactérias/imunologia , Células Dendríticas/imunologia , Vetores Genéticos/imunologia , Streptococcus gordonii/imunologia , Receptores Toll-Like/agonistas , Vacinas/efeitos adversos , Animais , Citocinas/biossíntese , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 2 Toll-Like/imunologia , Receptores Toll-Like/imunologia , Vacinas/administração & dosagem , Vacinas/imunologia
9.
Vaccine ; 37(2): 289-295, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30528592

RESUMO

INTRODUCTION/HYPOTHESIS: Recruitment of participants into phase 1 vaccine clinical trials can be challenging since these vaccines have not been used in humans and there is no perceived benefit to the participant. Occasionally, as was the case with a phase 1 clinical trial of an Ebola vaccine in Halifax, Canada, during the 2014-2016 West African Ebola virus outbreak, recruitment is less difficult. In this study, we explored the motivations of participants in two phase 1 vaccine trials that were concurrently enrolling at the same centre and compared the motivations of participants in a high-profile phase 1 Ebola vaccine trial to those in a less high-profile phase 1 adjuvanted seasonal influenza vaccine study. METHODS: An online survey which included participants' prior experience with clinical trials, motivations to participate (including financial incentives), and demographic information was developed to examine the motivations of healthy participants in two phase 1 clinical vaccine trials conducted at the Canadian Center for Vaccinology in Halifax, Nova Scotia. Participants were invited via email to complete the online survey. Readability and clarity were assessed through pilot testing. RESULTS: A total of 49 (55.7%) of 88 participants of the two studies completed the survey (22 [55%] of 40 participants from the Ebola vaccine study and 27 [56.3%] of 48 from the adjuvanted influenza vaccine study). Motivations that were most frequently ranked among participants' top three in both trials were (1) wanting to contribute to the health of others, (2) wanting to participate in something important, (3) wanting to contribute to the advancement of science, and (4) wanting to receive an incentive such as money or a tablet. CONCLUSIONS/RECOMMENDATIONS: Although media attention and financial compensation were more often cited by Ebola vaccine trial participants as a reason to participate, both altruistic and self-interested factors were important motivations for participants in their decision to participate in a phase 1 vaccine clinical trial.


Assuntos
Vacinas contra Ebola/administração & dosagem , Voluntários Saudáveis/psicologia , Vacinas contra Influenza/administração & dosagem , Motivação , Participação do Paciente/psicologia , Adolescente , Adulto , Altruísmo , Canadá , Ensaios Clínicos Fase I como Assunto , Surtos de Doenças/prevenção & controle , Feminino , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto , Inquéritos e Questionários , Adulto Jovem
10.
Vaccine ; 35(18): 2520-2530, 2017 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-28347501

RESUMO

OBJECTIVES: During an outbreak of invasive meningococcal B disease on a university campus, we explored the knowledge, attitudes, beliefs, and behaviors of members of the university community in relation to the disease, the vaccine, and the vaccination program. DESIGN: All students, faculty and staff were invited by email to participate in a 71-item online survey, which was administered after completion of the mass clinics for the first and second doses of a meningococcal B vaccination program. RESULTS: A total of 404 individuals responded to the survey; 75.7% were students. Knowledge about meningococcal disease and vaccine was generally high; more than 70% correct responses were received on each knowledge question except for one question about the different meningococcal serogroups. Gender (female) and higher knowledge scores were significantly associated with either being immunized or intending to be immunized (p<0.05). Positive attitudes about immunization, concern about meningococccal infection, a sense of community responsibility, and trust in public health advice also correlated with being vaccinated or intending to be vaccinated (p<0.05). CONCLUSIONS: A successful mass vaccination program in a Nova Scotia university was associated with high levels of knowledge, positive attitudes toward vaccination, and positive attitudes toward public health recommendations.


Assuntos
Surtos de Doenças , Conhecimentos, Atitudes e Prática em Saúde , Vacinação em Massa , Meningite Meningocócica/epidemiologia , Meningite Meningocócica/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Adolescente , Adulto , Idoso , Animais , Docentes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nova Escócia/epidemiologia , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
11.
Hum Vaccin Immunother ; 12(3): 623-31, 2016 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-26810485

RESUMO

Vaccine coverage among adults for recommended vaccines is generally low. In Canada and the US, pharmacists are increasingly becoming involved in the administration of vaccines to adults. This study measured the knowledge, attitudes, beliefs, and behaviors of Canadian adults and health care providers regarding pharmacists as immunizers. Geographically representative samples of Canadian adults (n = 4023) and health care providers (n = 1167) were surveyed, and 8 focus groups each were conducted nationwide with adults and health care providers. Provision of vaccines by pharmacists was supported by 64.6% of the public, 82.3% of pharmacists, 57.4% of nurses, and 38.9% of physicians; 45.7% of physicians opposed pharmacist-delivered vaccination. Pharmacists were considered a trusted source of vaccination information by 75.0% of the public, exceeding public health officials (68.3%) and exceeded only by doctors and nurses (89.2%). Public concerns about vaccination in pharmacies centered on safety (management of adverse events), record keeping (ensuring their family physician was informed), and cost (should be no more expensive than vaccination at public health or physicians' offices). Concerns about the logistics of vaccination delivery were expressed more frequently in regions where pharmacists were not yet immunizing than in jurisdictions with existing pharmacist vaccination programs. These results suggest that the expansion of pharmacists' scope of practice to include delivery of adult vaccinations is generally accepted by Canadian health care providers and the public. Acceptance of this expanded scope of pharmacist practice may contribute to improvements in vaccine coverage rates by improving vaccine accessibility.


Assuntos
Imunização/métodos , Aceitação pelo Paciente de Cuidados de Saúde , Farmacêuticos , Vacinas/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Vaccine ; 34(34): 4046-9, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27302338

RESUMO

An outbreak of Neisseria meningitidis serotype B infection occurred at a small residential university; public health announced an organizational vaccination program with the 4-component Meningococcal B (4CMenB) vaccine (Bexsero(TM), Novartis/GlaxoSmithKline Inc.) several days later. Since there were limited published data on reactogenicity of 4CMenB in persons over 17years of age, this study sought to conduct rapid surveillance of health events in vaccinees and controls using an online survey. Vaccine uptake was 84.7% for dose 1 (2967/3500) and 70% (2456/3500) for dose 2; the survey response rates were 33.0% (987/2967) and 18.7% (459/2456) in dose 1 and dose 1 recipients respectively, and 12% in unvaccinated individuals (63/533). Most students were 20-29years of age (vaccinees, 64.0%; controls, 74.0). A new health problem or worsening of an existing health problem was reported by 30.0% and 30.3% of vaccine recipients after doses 1 and 2 respectively; and by 15.9% of controls. These health problems interfered with the ability to perform normal activities in most vaccinees reporting these events (74.7% post dose 1; 62.6% post dose 2), and in 60% of controls. The health problems led to a health care provider visit (including emergency room) in 12.8% and 14.4% of vaccinees post doses 1 and 2, respectively and in 40% of controls. The most common reactions in vaccinees were injection site reactions (20.6% post dose 1, 16.1% post dose 20 and non-specific systemic complaints (22.6% post dose 1, 17.6% post dose 2). No hospitalizations were reported. An online surveillance program during an emergency meningococcal B vaccine program was successfully implemented, and detected higher rates of health events in vaccinees compared to controls, and high rates of both vaccinees and controls seeking medical attention. The types of adverse events reported by young adult vaccinees were consistent with those previously.


Assuntos
Vacinação em Massa , Infecções Meningocócicas/prevenção & controle , Vacinas Meningocócicas/administração & dosagem , Vacinação/efeitos adversos , Adolescente , Adulto , Canadá , Feminino , Humanos , Internet , Masculino , Vacinas Meningocócicas/efeitos adversos , Vacinas Meningocócicas/uso terapêutico , Neisseria meningitidis Sorogrupo B , Vigilância da População , Vigilância de Produtos Comercializados , Inquéritos e Questionários , Universidades , Adulto Jovem
13.
Mol Immunol ; 28(3): 247-50, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1708105

RESUMO

The epitope specificity of two monoclonal antibodies against the S1 subunit (A4, A12) and one MAb against the S3 subunit (B9) of pertussis toxin, all protective in the mouse aerosol model of B. pertussis infection, but with different effects in assays of toxin-neutralizing activity, was examined in competitive binding enzyme immunoassays using biotinylated anti-pertussis toxin monoclonal antibodies or biotinylated goat anti-pertussis toxin polyclonal antibody after preincubation with unlabelled antibody. Biotinylated A4 was blocked by A4, A12, and B9; A12 was blocked by A4, A12, and B9. In contrast, biotinylated B9 was blocked by B9 and A4, but not by A12. All three monoclonal antibodies successfully blocked the anti-pertussis toxin polyclonal antibody; a mixture of the three anti-pertussis toxin monoclonal antibodies was more effective than any monoclonal antibody alone P less than or equal to 0.01). These data suggest that these three anti-pertussis toxin monoclonal antibodies recognize separate, but closely linked epitopes on pertussis toxin, and that epitopes on the S1 subunit and B-oligomer may induce protective immunity.


Assuntos
Antitoxinas/imunologia , Toxina Pertussis , Fatores de Virulência de Bordetella/imunologia , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Ligação Competitiva , Bordetella pertussis/imunologia , Epitopos , Camundongos , Vacina contra Coqueluche/imunologia , Relação Estrutura-Atividade , Fatores de Virulência de Bordetella/química
14.
Hum Vaccin Immunother ; 11(9): 2167-79, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26090861

RESUMO

The tetanus, diphtheria, and acellular pertussis vaccine (Tdap) is recommended for all adults in both Canada and the United States. There are few data on the proportion of Canadian adults vaccinated with Tdap; however, anecdotal reports indicate that uptake is low. This study aimed to explore the knowledge, attitudes, beliefs, and behaviors of Canadian health care providers (HCPs) in an attempt to identify potential barriers and facilitators to Tdap uptake. HCPs were surveyed and a geographic and practice representative sample was obtained (N =1,167). In addition, 8 focus groups and 4 interviews were conducted nationwide. Results from the survey indicate that less than half (47.5%) of all respondents reported being immunized with Tdap themselves, while 58.5% routinely offer Tdap to their adult patients. Knowledge scores were relatively low (63.2% correct answers). The best predictor of following the adult Tdap immunization guidelines was awareness of and agreement with those recommendations. Respondents who were aware of the recommendations were more likely to think that Tdap is safe and effective, that their patients are at significant risk of getting pertussis, and to feel that they have sufficient information (p < 0.0001 for each statement). Focus group data supported the survey results and indicated that there are substantial gaps in knowledge of pertussis and Tdap among Canadian HCPs. Lack of public knowledge about adult immunization, lack of immunization registries, a costing differential between Td and Tdap, workload required to deliver the vaccine, and vaccine hesitancy were identified as barriers to compliance with the national recommendations for universal adult immunization, and suggestions were provided to better translate recommendations to front-line practitioners.


Assuntos
Atitude do Pessoal de Saúde , Vacinas contra Difteria, Tétano e Coqueluche Acelular/administração & dosagem , Vacinas contra Difteria, Tétano e Coqueluche Acelular/imunologia , Conhecimentos, Atitudes e Prática em Saúde , Competência Profissional , Vacinação/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá , Feminino , Pessoal de Saúde , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Mucosal Immunol ; 8(1): 94-106, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24938746

RESUMO

Regulatory B (Breg) cells are known to modulate immune responses through predominantly interleukin-10 (IL-10)-dependent mechanisms and can be hypothetically divided into innate and adaptive subsets based on the nature of their activating signals. However, the specific role of different Breg subsets in modulating immune responses remains ambiguous. Here we have shown that Chlamydia induces IL-10-producing splenic B-cell populations consisting of CD43(+) and CD43(-) subsets of IgM(hi)IgD(lo) innate-like B (ILB) cells in vitro. While CD43(+)IL-10-producing B cells displayed innate type features and were readily induced by Chlamydia via Toll-like-receptor (TLR) signaling, CD43(-)IL-10-producing B cells required additional B-cell activating factor (BAFF)-mediated signals from dendritic cells (DCs) for their differentiation and activation, thereby classifying them as adaptive type Bregs. Importantly, CD43(-), but not CD43(+), IL-10-producing ILB cells displayed bona fide Breg activity by potently suppressing interferon-γ (IFN-γ) production in vitro in an IL-10-dependent manner. Furthermore, a novel CD43(-)CD1d(hi)CD5(+) IL-10-producing Breg population was predominantly induced by Chlamydia genital infection in vivo. Correspondingly, mixed bone marrow chimeric mice with B-cell-specific IL-10 deficiency exhibited significantly increased type 1 immune responses, decreased bacterial burden, and reduced oviduct pathology upon infection. Our data demonstrate for the first time a distinct role for CD43(-)CD1d(hi)CD5(+)-adaptive Bregs over CD43(+) innate counterparts in controlling mucosal responses against intracellular bacterial infection.


Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos B Reguladores/imunologia , Infecções por Chlamydia/imunologia , Chlamydia muridarum/imunologia , Células Dendríticas/imunologia , Genitália/imunologia , Imunidade Adaptativa , Animais , Antígenos CD1/metabolismo , Receptor do Fator Ativador de Células B/metabolismo , Carga Bacteriana , Antígenos CD5/metabolismo , Diferenciação Celular , Células Cultivadas , Quimera , Genitália/microbiologia , Imunidade Inata , Cadeias mu de Imunoglobulina/genética , Terapia de Imunossupressão , Interleucina-10/genética , Interleucina-10/metabolismo , Leucossialina/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo
16.
Vaccine ; 33(48): 6840-8, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26392011

RESUMO

Tetanus, diphtheria, and acellular pertussis vaccine (Tdap) is recommended for all adults in Canada but uptake is low. This study measured the knowledge, attitudes, beliefs, and behaviors of Canadian adults to identify potential barriers and facilitators to Tdap uptake. A survey was undertaken on a geographically representative sample of Canadian adults (n=4023) and 8 focus groups (62 participants) were conducted nationwide. The survey revealed that knowledge about pertussis and Tdap was low (38.3% correct answers). Only 36.0% of respondents reported being aware that all adults were recommended to receive Tdap and only 10.7% reported being immunized; 36.7% did not know whether they had received Tdap. Respondents who were aware of the immunization recommendations were twice as likely to be immunized (16.6% vs. 8.3%; p<0.001). Only 9.3% believed that their health care provider thought that Tdap was important for adults. The focus group data supported the survey results. Participants wanted information about pertussis and Tdap communicated through multiple modalities, but a recommendation by their family physician was most important to their decision to be immunized or not. This study demonstrates that current recommendations for universal adult vaccination with Tdap are not reaching the general public in Canada and an alternative strategy will be required to improve Tdap vaccine uptake.


Assuntos
Vacinas contra Difteria, Tétano e Coqueluche Acelular/administração & dosagem , Vacinas contra Difteria, Tétano e Coqueluche Acelular/imunologia , Conhecimentos, Atitudes e Prática em Saúde , Coqueluche/epidemiologia , Coqueluche/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Vacinação/estatística & dados numéricos , Adulto Jovem
17.
BMJ Open ; 5(9): e009062, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26419683

RESUMO

OBJECTIVES: Vaccine coverage for recommended vaccines is low among adults. The objective of this study was to assess the knowledge, attitudes, beliefs and behaviours of adults and healthcare providers related to four vaccine-preventable diseases and vaccines (diphtheria-tetanus-pertussis, zoster, pneumococcus and influenza). DESIGN: We undertook a survey and focus groups of Canadian adults and healthcare providers (doctors, nurses, pharmacists). A total of 4023 adults completed the survey and 62 participated in the focus groups; 1167 providers completed the survey and 45 participated in the focus groups. RESULTS: Only 46.3% of adults thought they were up-to-date on their vaccines; 30% did not know. In contrast, 75.6% of providers reported being up-to-date. Only 57.5% of adults thought it was important to receive all recommended vaccines (compared to 87.1-91.5% of providers). Positive attitudes towards vaccines paralleled concern about the burden of illness and confidence in the vaccines, with providers being more aware of disease burden and confident in vaccine effectiveness than the public. Between 55.0% and 59.7% of adults reported willingness to be vaccinated if recommended by their healthcare provider. However, such recommendations were variable; while 77.4% of the public reported being offered and 52.8% reported being recommended the influenza vaccine by their provider, only 10.8% were offered and 5.6% recommended pertussis vaccine. Barriers and facilitators to improved vaccine coverage in adults, such as trust-mistrust of health authorities, pharmaceutical companies and national recommendations, autonomy versus the public good and logistical issues (such as insufficient time and lack of vaccination status tracking), were identified by both the public and providers. CONCLUSIONS: Despite guidelines for adult vaccination, there are substantial gaps in knowledge and attitudes and beliefs among both the public and healthcare providers that lead to low vaccine coverage. A systematic approach that involves education, elimination of barriers and establishing and improving infrastructure for adult immunisation is required.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Vacinação/psicologia , Adulto , Idoso , Canadá , Vacina contra Difteria, Tétano e Coqueluche , Feminino , Grupos Focais , Vacinas contra Herpesvirus , Humanos , Vacinas contra Influenza , Masculino , Pessoa de Meia-Idade , Vacinas Pneumocócicas , Inquéritos e Questionários , Adulto Jovem
18.
Can Commun Dis Rep ; 41(Suppl 1): 18-23, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29769957

RESUMO

The Public Health Agency of Canada / Canadian Institutes of Health Research Influenza Research Network (PCIRN), established in 2009 to undertake evaluative research to inform public health decision making in Canada, is now being replaced by the Canadian Immunization Research Network (CIRN), which will retain the mandate of PCIRN but expand it to all vaccines including influenza vaccine. CIRN is organized as a network of networks focusing on undertaking research in the areas of vaccine safety, adverse events following immunization (AEFIs), vaccine hesitancy, vaccine effectiveness, and vaccine coverage. CIRN's networks include: a clinical trial network; a laboratory network; a modelling and economics network; a network of social science and humanities researchers; a vaccine safety surveillance network; a hospital-based surveillance network; a clinic network to evaluate serious AEFIs; and a network that links vaccine research capacity in provincial health agencies and departments. PCIRN has contributed to Canada's vaccine safety surveillance system and has facilitated the translation of safety research into policy. Vaccine safety surveillance and research will remain a focus of the newly formed Canadian Immunization Research Network.

19.
Lancet Infect Dis ; 2(12): 744-50, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12467690

RESUMO

Bordetella pertussis continues to circulate even in populations where a high vaccine coverage of infants and children is achieved. Cases in adolescents and adults are reported with increasing frequency in many countries. Adults are a reservoir for infections in very young infants, in whom pertussis may be severe and life-threatening. The salient clinical feature of pertussis in adolescents and adults is prolonged coughing, and recognising that pertussis does occur in these age groups is the most important step in its diagnosis. A laboratory diagnosis can be made by bordetella-PCR from nasopharyngeal swabs or secretions and by detection of antibodies, mainly to pertussis toxin; laboratory diagnosis is, however, not well standardised. Vaccination of adolescents and adults is now possible with acellular pertussis vaccines, which are well tolerated, immunogenic, and effective. Adolescent boosters and the vaccination of health-care workers are already included in vaccination calendars in some countries. Vaccine-recommending bodies and national health-care organisations must have locally relevant information on the transmission of pertussis from adults to infants to be able to make decisions on the advisability, feasibility, and priority for booster immunisation against pertussis.


Assuntos
Coqueluche , Adulto , Bordetella pertussis/imunologia , Ensaios Clínicos Controlados como Assunto , Humanos , Lactente , Vacina contra Coqueluche/imunologia , Fatores de Risco , Vacinas Acelulares/imunologia , Coqueluche/diagnóstico , Coqueluche/epidemiologia , Coqueluche/imunologia , Coqueluche/prevenção & controle
20.
Pediatrics ; 104(1 Pt 1): 1-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10390252

RESUMO

OBJECTIVE: The purpose of this study was to assess the direct medical costs and productivity losses associated with uncomplicated chickenpox (no hospitalization) in Canada. METHODS: A total of 179 otherwise healthy 1- to 9-year-old children with active chickenpox were recruited from schools, day care centers, and physician offices in 5 provinces. Direct medical (physician contacts, medication, and diagnostic tests) and nonmedical (personal expenses including child care) resources expended during the illness were determined by caregiver interview. Productivity losses attributable to the disease were determined by assessing caregiver time lost from work and daily activities. Unit costs for all resources were obtained from sources in 2 provinces, and per-patient treatment costs were determined from the patient, Ministry of Health, and societal perspectives. RESULTS: From a societal perspective, the per-case cost for children from 1 to 4 years of age and from 5 to 9 years of age was $370.2 and $236.5, respectively. Direct medical costs accounted for 10% of the total costs in both groups. The largest cost driver in patient care was caregiver productivity losses, which amounted to $316.5 in the younger age group and to $182.7 in the older age group. Based on an estimated yearly incidence of 344 656 cases of uncomplicated chickenpox in Canada, the total annual societal burden of the disease can be estimated at $109.2 million, with a cost to the Ministry of Health of $11.2 million. CONCLUSION: Chickenpox is one of the last common childhood diseases prevalent in Canada, and the uncomplicated disease, despite its rather benign course, imparts a large annual economic burden.


Assuntos
Varicela/economia , Efeitos Psicossociais da Doença , Custos Diretos de Serviços , Canadá , Cuidadores/economia , Criança , Pré-Escolar , Licença para Cuidar de Pessoa da Família/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos
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