RESUMO
AIMS/OBJECTIVES: To describe the impact of additional testing on the England blood supply. BACKGROUND: The blood service for England, NHS Blood and Transplant, applies a system of deferral and testing to donors with potential exposure to Chagas disease, malaria and West Nile virus; however, testing costs must be justified. Here, we describe the donations and donors gained by testing. METHODS: Donation testing results and demographic data on donors in England where additional testing was applied were analysed in 2012-2016. The total number and proportion of donations tested, reactive and confirmed positive were calculated. Proportions of donors requiring additional tests were calculated by ethnic group for first-time and repeat donors. RESULTS: Additional testing for travel was applied to 3·5% of NHSBT blood donations between 2012 and 2016. Over 98% of these tests were non-reactive. Only malaria tests were confirmed positive, in 1·7% of donations tested. In first-time donors, 45 and 40% of Asian and Black donors required an additional test, respectively, mainly for malaria. Testing for West Nile virus increased from 1·5% in 2012 to 2·2% of donations in 2016. CONCLUSION: The majority of additional tests were screened negative, allowing approximately 64 000 donations to be released for issue annually. Donors most affected by malaria testing were more likely to have rare blood groups and be targeted for recruitment, whereas those given West Nile virus testing were mainly regular donors required for continuity of supply. These data show differences in the characteristics of donors by test and can be used to inform decisions about additional testing and deferrals.
Assuntos
Doadores de Sangue , Doença de Chagas/sangue , Seleção do Doador , Malária/sangue , Viagem , Febre do Nilo Ocidental/sangue , Inglaterra , Humanos , Vírus do Nilo OcidentalRESUMO
AIMS/OBJECTIVES: Here, we describe the annual review of the UK blood services' infection surveillance schemes for 2017 (www.gov.uk/government/publications/safe-supplies-annual-review). BACKGROUND: The joint NHS Blood and Transplant/Public Health England Epidemiology Unit was set up in 1995 to ensure that blood and tissue safety is maintained, inform donor selection and testing policy and add to public health knowledge. METHODS: Several surveillance schemes for blood, tissues and bacterial screening collect the numbers of donations tested, reactive and confirmed positive in order to monitor trends in infection rates in donors and calculate residual risk of infection. Investigations of potential transfusion transmissions in recipients are also monitored. RESULTS: In the UK in 2017, the risk of testing not detecting a potentially infectious hepatitis B virus or hepatitis C virus or HIV donation was estimated as less than one in two million donations. One hepatitis A virus and one hepatitis E virus transmission incidents were proven to be transfusion-transmitted by unscreened donations. CONCLUSIONS: The Safe Supplies annual review provides a clear picture of the very low risk associated with blood and tissues in the UK nowadays. In November 2017, the blood services for England, Wales and Scotland implemented recommendations to reduce the deferrals for higher risk sexual behaviour from 12 to 3 months. The surveillance schemes are adapted to remain fit for purpose as testing and donor selection change.
Assuntos
Doadores de Sangue , Segurança do Sangue , Reação Transfusional/prevenção & controle , Viroses/prevenção & controle , Seleção do Doador , Humanos , Reação Transfusional/epidemiologia , Reino Unido/epidemiologia , Viroses/epidemiologia , Viroses/transmissãoRESUMO
BACKGROUND AND OBJECTIVES: Between February 2011 and December 2016, over 1·6 million platelet units, 36% pooled platelets, underwent bacterial screening prior to issue. Contamination rates for apheresis and pooled platelets were 0·02% and 0·07%, respectively. Staphylococcus aureus accounted for 21 contaminations, including four pooled platelets, one confirmed transfusion-transmitted infection (TTI) and three 'near-miss' incidents detected on visual inspection which were negative on screening. We describe follow-up investigations of 16 donors for skin carriage of S. aureus and molecular characterisation of donor and pack isolates. MATERIALS AND METHODS: Units were screened by the BacT/ALERT 3D detection system. Contributing donors were interviewed and consent requested for skin and nasal swabbing. S. aureus isolates were referred for spa gene type and DNA macrorestriction profile to determine identity between carriage strains and packs. RESULTS: Donors of 10 apheresis and two pooled packs screen positive for S. aureus were confirmed as the source of contamination; seven had a history of skin conditions, predominantly eczema; 11 were nasal carriers. The 'near-miss' incidents were associated with apheresis donors, two donors harboured strains indistinguishable from the pack strain. The TTI was due to a screen-negative pooled unit, and a nasal isolate of one donor was indistinguishable from that in the unit. CONCLUSION: Staphylococcus aureus contamination is rare but potentially harmful in platelet units. Donor isolates showed almost universal correspondence in molecular type with pack isolates, thus confirming the source of contamination. The importance of visual inspection of packs prior to transfusion is underlined by the 'near-miss' incidents.
RESUMO
BACKGROUND AND OBJECTIVES: The rate of confirmed hepatitis C virus (HCV) cases, in first-time donors, is much lower in 2015 than 20 years ago. We investigate reasons for the decline. MATERIALS AND METHODS: HCV rates were analysed by gender and birth cohort for 1996 to 2015 and ethnic group for 2006 to 2015. Variables for confirmed positive cases were compared for two ten-year periods (1996 to 2005 and 2006 to 2015) including genotyping data for 2006 to 2015. RESULTS: There were 2007 confirmed HCV cases identified between 1996 and 2015. The rate per 100 000 donations fell from 78·6 in 1996 to 26·9 by 2015. By birth cohort, HCV rates were highest in donors born in the 1950s and 1960s who contributed a decreasing proportion of first-time donors. Between 2006 and 2015, there was no significant decline in HCV rate. The HCV-positive donor profile has changed in the last 10 years with increased proportions of younger donors, donors born abroad and decreased reported injecting drug use. Genotype 1a remains predominate, but genotype 1b has increased associated with this change in birth cohort and ethnicity. CONCLUSION: The decline in number and rate of confirmed HCV-positive first-time donors is mainly due to a decrease in first-time donors born before 1970, with the highest rate of HCV. However, the decline has slowed and the profile of HCV-positive first-time donors is changing. A better understanding of behaviour and sources of HCV in younger and ethnic minority donors are needed.
Assuntos
Doadores de Sangue/estatística & dados numéricos , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Inglaterra , Feminino , Genótipo , Hepacivirus/genética , Hepatite C/sangue , Humanos , Masculino , Testes Sorológicos , País de GalesRESUMO
BACKGROUND/OBJECTIVES: When NHS Blood and Transplant (NHSBT) confirms a blood donation to have markers of infection, the donor is contacted by letter to arrange a discussion about the test results and onward care. A survey was carried out to assess the level of satisfaction with this process. MATERIALS/METHODS: A questionnaire was sent to 335 donors who had been notified by NHSBT in 2008 and 2009 that they had tested positive for hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) or human T-cell lymphotropic virus (HTLV). Ratings were made using Likert scales, where the respondent indicated the level of agreement or satisfaction with statements about the initial notification letter and the subsequent post-test discussion (PTD) with the NHSBT clinician. RESULTS: There was an overall 47.5% (159/335) response rate. Fifty-eight percent (91/157) agreed that they were satisfied with the letter, but 30% (46/152) disagreed that it was easy to stay calm (average score 3.2). Scores for the letter were significantly lower in HIV and HTLV than in hepatitis for several questions. Scores for the discussion were in general higher than the initial letter, with 90% (114/127) satisfied overall, although 2 of 19 HIV positive donors remained dissatisfied. CONCLUSION: Overall, most donors were satisfied with the notification process, although scores were slightly lower for HTLV and HIV. Further audit is planned; in particular to remeasure the satisfaction with, and understanding of, the notification letter for HTLV positive donors and the telephone PTD.
Assuntos
Doadores de Sangue , Satisfação Pessoal , Inquéritos e Questionários , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos PilotoRESUMO
An important element in the development of voluntary blood donation schemes throughout the world has been the attention given to minimising the risk to recipients of donated blood, primarily the risk of transfusion transmitted infections. In response to the appearance of human immunodeficiency virus (HIV) in the 1980s a range of national policies emerged that excluded populations at high risk of contracting HIV from donating blood, with a particular focus on men who have sex with men (MSM), the primary reason being the protection of recipients of donated blood. Recently some countries, including the UK, have revised their policies, informed by advances in screening tests, epidemiological evidence of transmission rates and an increasing concern about unfair discrimination of specific groups in society. Policy makers face a difficult task of balancing safety of recipients; an adequate blood supply for those who require transfusion; and societal/legal obligations to treat everyone fairly. Given that no transfusion is risk free, the question is what degree of risk is acceptable in order to meet the needs of recipients and society. Decisions about acceptance of risk are complex and policy makers who set acceptable risk levels must provide ethically justifiable reasons for their decisions. We suggest it is possible to provide a set of reasons that stakeholders could agree are relevant based on careful evaluation of the evidence of all relevant risks and explicit acknowledgement of other morally relevant values. We describe using such a process in the Safety of Blood Tissue and Organs (SaBTO) review of donor deferral criteria related to sexual behaviour.
Assuntos
Doadores de Sangue , Seleção do Doador/normas , Doadores de Sangue/ética , Segurança do Sangue/ética , Segurança do Sangue/normas , Patógenos Transmitidos pelo Sangue , Canadá , Seleção do Doador/ética , Ética , Europa (Continente) , Feminino , Política de Saúde , Humanos , Controle de Infecções/normas , Masculino , Risco , Medição de Risco , Gestão de Riscos , Assunção de Riscos , Comportamento Sexual , Justiça Social , Valores Sociais , Reino UnidoRESUMO
OBJECTIVE: To design and pilot a survey of UK blood donors to assess, on a large scale, their understanding of and compliance with the donor selection guidelines (DSG). BACKGROUND: Compliance with the DSG is important for maintaining blood safety, however, little is currently known about the extent of this among UK donors. MATERIALS AND METHODS: The online, unlinked survey was based on the donor health check form with a focus on behaviours associated with blood borne infections, sexual contact, drug use and travel. The survey materials were reviewed by a donor focus group and the survey was piloted among 2982 UK donors. Percentage responses were calculated, complaints monitored and answers to questions reviewed. The survey went live in 2013; 225 091 donors were invited via email to participate followed by two reminders. RESULTS: The survey was well received by the focus group, with little concern about the sensitive and personal questions. Their feedback led to important refinement in the survey materials. In the pilots, 21·0% (627/2982) responded, a reminder was necessary to achieve this. Among responders, there was evidence of non-compliance and test seeking behaviour, and no evidence that intention to donate again was affected. In the live survey, 29% (65 439) responded; responders were generally representative of donors overall. CONCLUSION: A large scale survey of donor compliances is feasible, acceptable and effective in ascertaining appropriate information; involving donors and the blood services in the development stages through a focus group and pilots was important to achieve this.
Assuntos
Doadores de Sangue/psicologia , Inquéritos Epidemiológicos , Adolescente , Adulto , Patógenos Transmitidos pelo Sangue , Doenças Transmissíveis/epidemiologia , Confidencialidade , Comportamento Cooperativo , Seleção do Doador , Estudos de Viabilidade , Feminino , Grupos Focais , Comportamentos Relacionados com a Saúde , Inquéritos Epidemiológicos/métodos , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Assunção de Riscos , Autorrelato , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Inquéritos e Questionários , Viagem , Revelação da Verdade , Reino Unido , Adulto JovemRESUMO
The risk of transfusion-transmitted HIV infection under (i) permanent exclusion and (ii) 12-month deferral of MSM in England and Wales during 2005-2007 was estimated. Assuming equal compliance with both scenarios, estimated risk under a 12-month deferral (0.228/million donations [range 0·168-0·306/million donations]) was only marginally greater (0·5%) than that under lifetime exclusion (0·227/million donations [range 0·157-0.318/million donations]), with one extra-HIV infectious donation every 455 years. Poorer compliance of MSM with a 12-month deferral would be expected to increase the estimated risk, whereas improved compliance could decrease risk by up to 29·1%.
Assuntos
Doadores de Sangue , Seleção do Doador , Fidelidade a Diretrizes , Infecções por HIV , Homossexualidade Masculina , Sexo sem Proteção , Inglaterra/epidemiologia , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , País de Gales/epidemiologiaRESUMO
BACKGROUND AND OBJECTIVES: During the 1918, pandemic blood components were successfully used to treat severe influenza pneumonia. A Proof of Principle trial investigating the clinical benefit of convalescent plasma was proposed in the 2009 H1N1v epidemic with the aim of screening donors for high titre antibody in order to stockpile plasma packs to be used for treatment for severe pneumonia. MATERIALS AND METHODS: Serum samples were collected from donors. IgG antibody capture format enzyme-linked immunoassays using recombinant proteins (GACELISAs) were compared with microneutralization (MN) and haemagglutination inhibition (HAI). The influence of age and history of influenza-like illness (ILI) on the detection of high titre antibody was examined. RESULTS: 1598 unselected donor sera collected in October and December 2009 were tested by HAI. The HAI and demographic data defined a possible strategy for selective donor screening. One of the GACELISAs was highly specific for recent infection but showed lower sensitivity than HAI. CONCLUSIONS: During the 2009 pandemic screening 17- to 30-year-old donors by HAI delivered around 10% with high antibody levels. The ELISA using a short recombinant H1N1v HA detected fewer reactives but was more specific for high titre antibody (≥1:256). Screening strategies are proposed based on using HAI on serum or GACELISA on plasma.
Assuntos
Anticorpos Antivirais/sangue , Doadores de Sangue , Convalescença , Seleção do Doador/métodos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/sangue , Influenza Humana/epidemiologia , Pandemias , Adolescente , Adulto , Inglaterra/epidemiologia , Feminino , Humanos , PlasmaAssuntos
Hepatite B/transmissão , Hepatite C/transmissão , Doadores de Sangue , Inglaterra , HumanosRESUMO
Actinomyces are Gram-positive pleomorphic rods (GPPR) which form a large proportion of the oral microflora of all mammals. They have been implicated in root caries, although their role in dental caries initiation and progression is not well-understood. Many studies have focused on Actinomyces naeslundii, but few reports have documented other members of the GPPR. Therefore, we investigated the GPPRs isolated from infected dentin of active root caries lesions (n = 9) to determine which species were the most frequently isolated. The GPPR were isolated under both aerobic and anaerobic conditions and identified by biochemical and physiological tests to the species level according to the new taxonomy. Of 654 GPPR isolates investigated, 607 were identified as belonging to the genus Actinomyces. Of these, 242 were identified as A. israelii, 225 as A. gerencseriae, 109 as A. naeslundii, 15 as A. odontolyticus, and 13 as A. georgiae. Individual strains of A. israelii (n = 56) and A. gerencseriae (n = 46) were also investigated at the DNA level by means of Repetitive Extragenic Palindromic polymerase chain-reactions (REP-PCR) for the study of clonal diversity. Although only a small number of isolates was investigated, REP-PCR showed that the genotypes of both A. gerencseriae and A. israelii populations were heterogeneous within individual root caries lesions. A. gerencseriae and A. israelii strains from the same lesions did not share the same REP-PCR patterns, showing the robustness of the identification scheme. A significantly greater proportion of A. gerencseriae was isolated from the aerobic plates (p < 0.05), while the proportion of A. israelii was significantly (p < 0.05) greater from anaerobic plates. The role of individual Actinomyces spp. in the root caries process remains unclear, since various populations of GPPRs were isolated from individual active root caries lesions.
Assuntos
Actinomyces/classificação , Actinomyces/isolamento & purificação , Dentina/microbiologia , Cárie Radicular/microbiologia , Actinomyces/genética , Bactérias Aeróbias/isolamento & purificação , Bactérias Anaeróbias/isolamento & purificação , Técnicas de Tipagem Bacteriana , Classificação , Impressões Digitais de DNA , DNA Bacteriano/análise , Variação Genética , Humanos , Reação em Cadeia da Polimerase/métodos , Especificidade da Espécie , Estatísticas não ParamétricasRESUMO
The reason that children with cleft palates tend to have a greater prevalence of tooth decay than normal children is unclear. We hypothesized that children with cleft palates would have increased oral clearance times for foods and, consequently, higher levels of caries and caries-associated micro-organisms than control children. Children aged 6-16 yrs, with (n = 81) or without (n = 61) cleft palates, were studied. Children with cleft palates had DMFT and dmft scores greater (p < 0.01) than those of the control group. The number of caries-associated organisms was greater in the saliva of the cleft palate children (all p < 0.001). The oral hygiene, plaque and gingival index scores were greater (p < 0.0001), oral clearance was longer (p < 0.01), and levels of sucrose and starch-derived saccharides higher (p < 0.01) in the cleft palate group. However, salivary concentrations of organic acids were lower in the children with craniofacial disorders, probably reflecting the altered physiology of the more mature dental biofilm. The longer oral clearance times of foods and the consequent generation of fermentable sugars from starches may contribute to the higher caries prevalence observed in children with cleft palates.
Assuntos
Fenda Labial/complicações , Fissura Palatina/complicações , Cárie Dentária/etiologia , Boca/metabolismo , Higiene Bucal , Adolescente , Biofilmes , Ácidos Carboxílicos/metabolismo , Distribuição de Qui-Quadrado , Criança , Fenda Labial/metabolismo , Fenda Labial/microbiologia , Fissura Palatina/metabolismo , Fissura Palatina/microbiologia , Contagem de Colônia Microbiana , Índice CPO , Cárie Dentária/microbiologia , Índice de Placa Dentária , Carboidratos da Dieta/metabolismo , Feminino , Humanos , Masculino , Boca/microbiologia , Índice de Higiene Oral , Índice Periodontal , Saliva/metabolismo , Saliva/microbiologia , Amido/metabolismoRESUMO
The etiology of root caries is not fully understood, and although mutans streptococci, lactobacilli, and A. naeslundii have been implicated in its initiation and progression, this study was designed to determine the potential role of other microbial species and the nature of predominant aciduric microflora in the root caries process. We isolated the predominant aciduric microflora from root-caries lesions (n = 14) and sound root surfaces in subjects with (n = 13) or without (n = 10) root caries, using both a "most probable numbers" method and conventional plating methods. The predominant aciduric bacteria from root lesions were lactobacilli and A. israelii, while from sound root surfaces in subjects with root caries, A. gerencseriae comprised over 60% of aciduric isolates. Mutans streptococci were not among the aciduric isolates. Subjects without root caries harbored fewer bacteria, and S. anginosus (pH 4.8) and S. oralis (pH 5.2) were the predominant aciduric bacteria. The microbial etiology of root caries is more complex than was previously appreciated, and factors underlying the microbial succession occurring during the disease process are not known. Taxa with previously unrecognized aciduric characteristics have been isolated routinely, and the role of these organisms in the root caries process requires further investigation.
Assuntos
Cárie Radicular/microbiologia , Actinomyces/isolamento & purificação , Idoso , Placa Dentária/microbiologia , Instituição de Longa Permanência para Idosos , Humanos , Concentração de Íons de Hidrogênio , Lactobacillus/isolamento & purificaçãoRESUMO
Three and four-year-old Caucasian and Afro-Caribbean children (n = 641) attending childcare facilities in the London boroughs of Lambeth, Lewisham and Southwark were studied in order to determine the prevalence of caries and caries-associated micro-organisms and the interactions between these for each of the racial groups; dmft (decayed, missing or filled teeth) scores were recorded using British Association for the Study of Community Dentistry criteria. Saliva and plaque samples were taken from each child and the numbers of mutans streptococci, lactobacilli and yeasts per sample were determined. The mean dmft scores of the 3- and 4-year-old Afro-Caribbean children were 0.36 +/- 0.10 and 0.51 +/- 0.13, respectively, compared to 0.80 +/- 0.17 and 1.48 +/- 0.24 for the equivalent Caucasian children (p < 0.001). Mutans streptococci and lactobacilli were recovered less frequently from the Afro-Caribbean children than from the Caucasian, but in both groups there were significant correlations between the plaque and salivary levels of mutants streptococci and caries experience. In both groups, children from whom both mutans streptococci and lactobacilli were isolated had the greatest mean dmft scores and these were not significantly different. Multiple regression analyses demonstrated that, after controlling for age and dmft, there were still significant associations between race and salivary levels of mutans streptococci and lactobacilli, p = 0.0013 and p = 0.0167, respectively. These data indicate that Afro-Caribbean children had lower levels of dental caries than Caucasian children living in the same London boroughs and attending the same preschool care facilities and, after controlling for age and caries experience, they also had lower salivary levels of mutans streptococci and lactobacilli.
Assuntos
População Negra , Cárie Dentária/epidemiologia , Placa Dentária/microbiologia , Etnicidade , Lactobacillus/isolamento & purificação , Saliva/microbiologia , Streptococcus mutans/isolamento & purificação , População Branca , África/etnologia , Fatores Etários , Região do Caribe/etnologia , Pré-Escolar , Contagem de Colônia Microbiana , Índice CPO , Cárie Dentária/microbiologia , Restauração Dentária Permanente/estatística & dados numéricos , Humanos , Londres/epidemiologia , Prevalência , Análise de Regressão , Perda de Dente/epidemiologia , Leveduras/isolamento & purificaçãoRESUMO
OBJECTIVES: To compare the clinical effects of a fluoride-containing varnish (Fluor-Protector) in combination with a chlorhexidine-containing varnish (Cervitec) on existing root caries lesions in a group of frail elderly subjects. METHODS: A randomised double blind longitudinal study was utilised. Subjects (n = 102) were randomly allocated to a Test or Placebo group. All leathery and soft root caries lesions in all subjects were coated with Fluor-Protector while the lesions in the Test group were also coated with Cervitec and the lesions in the Placebo group were coated with a Placebo varnish. Treatments were repeated five times in a 12-month period. Clinical parameters associated with root caries, measurements of individual lesions and salivary levels of caries associated bacteria were made at intervals. RESULTS: The clinical severity of the lesions in the Test group did not change significantly during the 12-month study period. In the Placebo group the mean lesion width and lesion height and length of exposed root increased significantly and the lesions were significantly closer to the gingival margin. There were no significant changes in the salivary levels of caries-associated microorganisms after 12 months although, in both groups, there was initially a significant reduction in the salivary levels of mutans streptococci. CONCLUSIONS: The combination of Fluor-Protector and Cervitec is a useful, simple, quick and non-invasive method for the control and management of existing root caries lesions. The procedure could be performed by a dental hygienist and may be usefully applied in other high-risk groups including persons with Parkinson's disease, debilitating neuromuscular conditions and dry mouth from whatever cause.
Assuntos
Clorexidina/uso terapêutico , Assistência Odontológica para Idosos/métodos , Forramento da Cavidade Dentária/métodos , Fluoretos Tópicos/uso terapêutico , Poliuretanos/uso terapêutico , Cárie Radicular/prevenção & controle , Silanos/uso terapêutico , Timol/uso terapêutico , Idoso/estatística & dados numéricos , Idoso de 80 Anos ou mais/estatística & dados numéricos , Índice CPO , Assistência Odontológica para Doentes Crônicos/métodos , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Idoso Fragilizado/estatística & dados numéricos , Humanos , Masculino , Índice de Higiene Oral , Instituições Residenciais , Cárie Radicular/epidemiologia , Autocuidado , Estatísticas não ParamétricasRESUMO
OBJECTIVES: The aim of this study was to determine if there are associations between the level of social deprivation/affluence and the frequency isolation of caries-associated micro-organisms (Streptococcus mutans, Streptococcus sobrinus, lactobacilli and yeasts) in a large cohort of infants examined annually from 1 to 4 years of age. METHODS: DEPCAT was used to measure the socio-economic status of all consented infants (n=1099--1392) born in Dundee during a 1 year period (total n=1974). Caries-associated micro-organisms were cultured from saliva when the infants were 1, 2, 3 and 4 years of age. Standardised dental examinations were also carried out annually. Log linear analysis, which controlled for caries, was used to look for associations between DEPCAT and the isolation frequency of caries-associated micro-organisms. RESULTS: When controlling for caries, there was an association between DEPCAT and the isolation frequency of yeasts when the infants were 1 and 2 but not when 3 and 4 years old, whereas lactobacilli were associated only when the infants were 3 and 4 years old. Correlations between S. mutans and social deprivation were usually dependent on the caries status of the infants. CONCLUSIONS: The relationship between social deprivation and the isolation frequencies of caries-associated micro-organisms is complex with lactobacilli developing an association when the infants were 3 and 4 years old in contrast to yeasts which were only associated when the infants were 1 and 2 years old. Streptococcus mutans was associated with social deprivation when the infants were 2 years old and older, but dependent on caries status in the 3 and 4 year olds.
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Cárie Dentária/epidemiologia , Cárie Dentária/microbiologia , Pobreza , Fatores Etários , Distribuição de Qui-Quadrado , Pré-Escolar , Humanos , Lactente , Lactobacillus/isolamento & purificação , Modelos Logísticos , Fatores de Risco , Saliva/microbiologia , Escócia/epidemiologia , Classe Social , Streptococcus mutans/isolamento & purificação , Streptococcus sobrinus/isolamento & purificação , Leveduras/isolamento & purificaçãoRESUMO
The effects of sealing infected carious dentine below dental restorations on the phenotypic and genotypic diversity of the surviving microbiota was investigated. It was hypothesized that the microbiota would be subject to nutrient limitation or nutrient simplification, as it would no longer have access to dietary components or salivary secretion for growth. The available nutrients would be limited primarily to serum proteins passing from the pulp through the patent dentinal tubules to the infected dentine. Ten lesions were treated, and infected dentine was sealed below dental restorations for approximately 5 months. Duplicate standardized samples of infected dentine were taken at baseline and after the removal of the restorations. The baseline microbiota were composed primarily of Lactobacillus spp., Streptococcus mutans, Streptococcus parasanguinis, Actinomyces israelii, and Actinomyces gerencseriae. None of these taxa were isolated among the microbiota of the dentine samples taken after 5 months, which consisted of only Actinomyces naeslundii, Streptococcus oralis, Streptococcus intermedius, and Streptococcus mitis. The microbiota of the final sample exhibited a significantly (P < 0.001) increased ability to produce glycosidic enzymes (sialidase, beta-N-acetylglucosaminidase, and beta-galactosidase), which liberate sugars from glycoproteins. The genotypic diversity of S. oralis and A. naeslundii was significantly (P = 0.002 and P = 0.001, respectively) reduced in the final samples. There was significantly (P < 0.001) greater genotypic diversity within these taxa between the pairs of dentine samples taken at baseline than was found in the 5-month samples, indicating that the dentine was more homogenous than it was at baseline. We propose that during the interval between placement of the restorations and their removal, the available nutrient, primarily serum proteins, or the relative simplicity and homogeneity of the nutrient supply significantly affected the surviving microbiota. The surviving microbiota was less complex, based on compositional, phenotypic, and genotypic analyses, than that isolated from carious lesions which were also exposed to salivary secretions and pH perturbations.
Assuntos
Contagem de Colônia Microbiana , Preparo da Cavidade Dentária , Dentina/microbiologia , Acetilglucosaminidase/metabolismo , Biofilmes , Genótipo , Humanos , Concentração de Íons de Hidrogênio , Neuraminidase/metabolismo , Fenótipo , beta-Galactosidase/metabolismoRESUMO
To compare the effects of fluoride-containing and fluoride-free toothpaste on plaque microflora, 15 subjects were enrolled in a double-blind crossover trial. All subjects used a fluoride toothpaste for 7 days before the trial started. Then, 4 interproximal sites per subject were professionally cleaned and subjects used one of the toothpastes for 5 days. On the 5th day plaque was collected from 2 sites, 12 and 6 h after toothpaste use. There was no difference between the groups in the numbers or proportions of aciduric bacteria (recovered at pH 4.8 or 5.2), or of yeasts, neisseriae, lactobacilli or streptococci (total or individual species, including Streptococcus mutans). However, the numbers and proportions of Gram-positive pleomorphic rods, primarily Actinomyces naeslundii, increased in 6-hour samples from subjects using fluoride toothpaste. The data suggest that the anti-caries effect of fluoride toothpaste is not mediated primarily through effects on the plaque microflora, although effects on plaque physiology could be important.
Assuntos
Cariostáticos/uso terapêutico , Placa Dentária/microbiologia , Fluoretos/uso terapêutico , Cremes Dentais/química , Adulto , Estudos Cross-Over , Placa Dentária/tratamento farmacológico , Método Duplo-Cego , Humanos , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Cremes Dentais/uso terapêuticoRESUMO
The relationship between microflora, eruption status and caries status in the first permanent molar of young children was investigated in 177 children aged 6-7 years. A significantly greater proportion of fully erupted teeth were classified as sound and plaque-free compared to partially erupted teeth. Fully erupted teeth yielded greater numbers and proportions of mutans streptococci compared with significantly greater numbers and proportions of Actinomyces israelii in partially erupted teeth. Logistical regression analysis showed significant associations between white spot lesions in partially erupted teeth and increased numbers of Streptococcus oralis, mutans streptococci and Streptococcus salivarius whereas the presence of Actinomyces naeslundii was associated with health. Significantly greater numbers and proportions of S. oralis and S. salivarius were isolated from partially erupted teeth with white spot lesions whereas Streptococcus mutans was isolated in significantly greater numbers and proportions from fully erupted molars with white spots. This study suggests that organisms other than mutans streptococci are associated with caries development in erupting permanent molar teeth.