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Background and Objectives: Donor selection questions differentially impacting ethnic minorities can discourage donation directly or via negative word-of-mouth. We explore the differential impact of two blood safety questions relating to (i) sexual contacts linked to areas where human immunodeficiency virus (HIV) rates are high and (ii) travelling to areas where malaria is endemic. Epidemiological data are used to assess infection risk and the need for these questions., Materials and Methods: We report two studies. Study 1 is a behavioural study on negative word-of-mouth and avoiding donation among ethnic minorities (n = 981 people from National Health Service Blood and Transplant (NHSBT) and the general population: 761 were current donors). Study 2 is an epidemiology study (utilizing NHSBT/UK Health Security Agency (UKHSA) surveillance data on HIV-positive donations across the UK blood services between1996 and 2019) to assess whether the sexual risk question contributes to reducing HIV risk and whether travel deferral was more prevalent among ethnic minorities (2015-2019). Studies 1 and 2 provide complementary evidence on the behavioural impact to support policy implications., Results: A high proportion of people from ethnic minorities were discouraged from donating and expressed negative word-of-mouth. This was mediated by perceived racial discrimination within the UK National Health Service. The number of donors with HIV who the sexual contact question could have deferred was low, with between 8% and 9.3% of people from ethnic minorities deferred on travel compared with 1.7% of White people., Conclusion: Blood services need to consider ways to minimize negative word-of-mouth, remove questions that are no longer justified on evidence and provide justification for those that remain., (© 2024 The Author(s). Vox Sanguinis published by John Wiley & Sons Ltd on behalf of International Society of Blood Transfusion.)

Background and Objectives: Homophily represents the extent to which people feel others are like them and encourages the uptake of activities they feel people like them do. Currently, there are no data on blood donor homophily with respect to (i) people's representation of the average prototypical UK blood donor and (ii) the degree of homophily with this prototype for current donors, non-donors, groups blood services wish to encourage (ethnic minorities), those who are now eligible following policy changes (e.g., men-who-have-sex-with-men: MSM) and recipients. We aim to fill these gaps in knowledge., Materials and Methods: We surveyed the UK general population MSM, long-term blood recipients, current donors, non-donors and ethnic minorities (n = 785) to assess perceptions of the prototypical donor in terms of ethnicity, age, gender, social class, educational level and political ideology. Homophily was indexed with respect to age, gender and ethnicity., Results: The prototypical UK blood donor is perceived as White, middle-aged, middle-class, college-level educated and left-wing. Current donors and MSM are more homophilous with this prototype, whereas recipients and ethnic minorities have the lowest homophily. Higher levels of homophily are associated with an increased likelihood of committing to donate., Conclusion: The prototype of the UK donor defined this as a White activity. This, in part, may explain why ethnic minorities are less likely to be donors. As well as traditional recruitment strategies, blood services need to consider broader structural changes such as the ethnic diversity of staff and co-designing donor spaces with local communities., (© 2024 The Author(s). Vox Sanguinis published by John Wiley & Sons Ltd on behalf of International Society of Blood Transfusion.)

In 2019 the For The Assessment Of Individualised Risk (FAIR) project began a review of UK blood donor selection policy to determine if a more individualised approach to donor selection could be safely implemented. An evidence base was required to inform selection policy to move from a population to a more individual based policy, specifically what sexual behaviours/indicators should be considered as screening questions to maintain the safety of the blood supply. Eight sexual behaviours/indicators were reviewed: history of bacterial sexually transmitted infections (STIs), chemsex, number of recent partners, condom use, type of sex, sexual health service (SHS) attendance, new sexual partner and exclusivity. We conducted searches in multiple databases to identify literature looking at the association between these behaviours/indicators and HIV/STI acquisition risk. A scoring system to determine strength of evidence was devised and applied to papers that passed screening. Key studies were identified which achieved the maximum score and more in-depth reviews were conducted for these. We identified 58 studies, including 17 key studies. Strong evidence was found linking a previous bacterial STI, chemsex and increasing numbers of sexual partners to acquisition risk. Condom use, type of sex and new partners were found to have some strength of evidence for this link. SHS attendance and exclusivity had minimal evidence. We recommended that the behaviours/indicators viewed as having strong or some strength of evidence should be considered as screening questions in a more individualised approach to donor selection criteria., (© 2024 The Author(s). Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Background: The UK's Infected Blood Inquiry (IBI) highlighted a major public health scandal, with at least 30 000 people infected and more than 3000 deaths attributable to infected blood and blood products. This study investigates the impact of the IBI announcement on May 20, 2024, on public perceptions of blood supply risk, safety, and donation intentions in the UK compared to the USA., Methods: A 2 (country: UK vs. USA) × 2 (time: pre-, post-IBI announcement) between-within-subject study was conducted with 1635 participants (888 UK, 747 USA). Pre-IBI data were collected from May 3 to 7, 2024, and post-IBI data from May 30 to June 30, 2024. Key measures were perceived infection risk from transfusion, transfusion safety, willingness to donate and encourage others. The impact was assessed using differences-in-differences (DiD) and reliable-change-indices (RCI)., Results: UK participants showed a significant but small decrease in perceived safety compared to USA participants, with 1 in 30 UK individuals perceiving a significant reduction in perceived transfusion safety. Decreases in perceived safety were associated with significant decreases in willingness to donate and encouragement of others in the whole sample and in USA participants and significant decreases in willingness to encourage others in UK participants. Older people reported a greater reduction in safety, and non-donors were more likely to be put off donating and not ask others to donate as a result of their perception that safety had been reduced., Conclusion: Overall, perceived safety decreased marginally in the UK general population. Future research should explore the long-term impacts of the IBI., (© 2024 The Author(s). Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

A more individualised donor selection policy was implemented in the UK in 2021, which replaced the previous 3-month deferral for men who have sex with men (MSM). Other blood services have a variety of policies in place to ensure the virological safety of blood components, ranging from an indefinite ban on MSM, to a defined period of exclusion, or to an individualised risk assessment that is not based on gender or sexual orientation. Justification of these policies should be based on scientific evidence including assessment of lengths of virological window periods, infectious disease epidemiology within donor populations and donation screening assay sensitivities. Developments in molecular technology and assays which can detect both antibodies and antigens in the very early stages of infection have significantly reduced the risk in most developed countries. However, the increasing usage of pre-exposure prophylaxis (PrEP) to prevent acquisition of HIV infection after possible high-risk sexual contact within the UK blood donor population has been recently noted. It has brought with it new diagnostic challenges within blood screening, notably possible non-detection of HIV RNA and serological markers following PrEP use despite potential infectivity. The use of other testing strategies such as detection of HIV DNA and screening for non-declared PrEP usage should be investigated further., (© 2023 British Blood Transfusion Society.)

Background: A large, worldwide outbreak of mpox (formerly referred to as monkeypox) involving mainly men who have sex with men commenced in May 2022. We evaluated the frequency of positivity for the causative agent, monkeypox virus (MPXV), in blood donations collected in August 2022, during the outbreak period in Southern England., Methods/materials: The sensitivity and specificity of an MPXV-specific PCR and a generic non-variola orthopoxvirus (NVO) PCR were evaluated using samples from mpox cases and synthetic DNA standards. Residual minipools from nucleic acid testing were obtained from 10,896 blood donors in Southern England, with 21% from London., Results: MPXV and NVO PCRs were both capable of detection of single copies of target sequence with calculated limits of detection (LOD) 90  s of 2.3 and 2.1 DNA copies and analytical sample sensitivities of 46 and 42 MPXV DNA copies/ml, respectively. 454 minipools produced from 10,896 unique donors were assayed for MPXV DNA by both methods. No positive minipools were detected by either PCR., Conclusions: Although blood donors are unrepresentative of the UK population in terms of MPXV infection risk, the uniformly negative MPXV DNA testing results provide reassurance that MPXV viraemia and potential transmission risk were rare or absent in donors during the outbreak period. Minipools from blood donors allow rapid implementation of large-scale population-based screening for emerging pathogens and represent an important resource for pandemic preparedness., (© 2023 The Authors. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

The supply of blood, blood products and components in the UK, as elsewhere, is safe, although there is no cause for complacency. Use of blood, blood products and components is not without risk of morbidity and mortality. Transfusion-transmitted infections (TTIs) continue to occur and may severely affect the health and welfare of recipients. As indicated by recent and current inquiries, public interest in these TTIs is huge. The risk of TTI can be mitigated but not abolished. Measures to reduce risk include screening of donors, testing of donations and, where appropriate, treatment of donations. The introduction of newer screening tests might identify some infectious donations but come at a cost, which could exceed a justifiable limit. Thus, the recognition, detection, reporting and investigation of cases of possible TTIs need to be improved. Recipients of blood should understand that, although transfusion in the UK is safe, it is not free of risk and so should be provided with full information so that properly informed consent can be given., (© Royal College of Physicians 2023. All rights reserved.)

An individualised blood donor selection policy was implemented in the United Kingdom from summer 2021. We have investigated the impact of this policy by comparing the extent of undeclared use of HIV pre-exposure or post-exposure prophylaxis (PrEP/PEP) before and after this change. The rate of PrEP usage in syphilis-positive male blood donors has not changed since individualised donor assessment was implemented but provides continuing evidence of undisclosed PrEP use which may be associated with current or past higher-risk sexual behaviours.

Background: Men-who-have-sex-with-men (MSM) have been deferred from donating blood. However, recent evidence supports the adoption of donor screening based on individuals' sexual behavior over population-based criteria. We explore how best to frame communications about adopting this change to minimize any potential negative consequences (e.g., reduced donor numbers). We examine the effectiveness of risk (emphasizing safety vs. emphasizing low risk), and focus (donor vs. recipient) frames on intentions to donate blood (approach) or feeling deterred from donating (avoid), and mechanisms linked to under-reporting sexual behavior., Study Design and Methods: We conducted a 2 (risk frame: risk vs. safety) by 3 (focus: donor vs. recipient vs. both) between-subjects online experiment (n = 2677). The main outcomes were intentions to donate and feelings of being put-off/deterred from donating (both for self and others). We also assessed the extent that forgetting, embarrassment/shame, and question irrelevance were perceived to be associated with under-reporting sexual behavior., Results: Frames that focused on safety or a recipient resulted in people reporting being less deterred from donating. Regardless of frame, people from ethnic minorities were more likely to feel deterred. Embarrassment/shame followed by forgetting and perceived irrelevance were the main reasons for under-reporting sexual behaviors, especially in ethnic minorities, and smartphones were perceived as an acceptable memory aid for sexual behavior., Discussion: Blood services moving to an individualized policy should frame donor selection in terms of safety and/or a recipient focus, explore sensitivities in ethnic minority communities, consider ways to normalize reporting sexual behavior, and use smartphones as a memory aid., (© 2022 The Authors. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

Background: We explore the role of trust, distrust, and the prevailing socio-political context to better understand why people from ethnic minority communities are less likely to be blood donors compared to people from White communities. Recruiting more ethnic minority donors will enhance representativeness, reduce inequality, and help meet the clinical need to increase the proportion of blood with Ro Kell antigen to treat Sickle Cell Disease (SCD)., Study Design and Methods: A 2 (donor-status: current donor; non-donors) by 4 (ethnicity: People from Asian, Black, Mixed and White ethnic backgrounds) quasi-experiment (N = 981) was conducted to examine perceptions of trust/distrust and their influence on willingness to donate blood, within the socio-political context of the Windrush scandal and Brexit., Results: We identified five domains of trust ('National Health Service [NHS] and staff,' 'NHS Blood and Transplant,' 'outgroups,' 'individuals' and 'politics'), and a single domain of conditional distrust domain. Trust across all the domains was lower, and 'conditional distrust' higher for ethnic minorities. Trust in 'individuals' and 'NHSBT' predicted willingness to donate in non-donors from ethnic minorities and White non-donors, respectively. Concerns about the Windrush scandal were related to lower political trust. Viewing Brexit as 'positive for the UK' was related to lower trust across domains and reduced willingness to donate in White non-donors through its influence on reduced trust in NHSBT., Conclusion: Distinct domains of trust and distrust are identified, and targeting 'trust in others' through conditional cooperation is recommended as a strategy to increase donor numbers from ethnic minority communities., (© 2022 The Authors. Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Testing of living surgical bone and deceased tissue donors by NHS Blood and Transplant (NHSBT) has included individual donation (ID) nucleic acid testing (NAT) for HBV, HCV and HIV since 2008. Here, the well-established window period methodology was used to estimate residual risk (RR). Prevalence of viral markers was calculated among both tissue donor populations. Incidence was derived by adjusting incidence among new blood donors by the prevalence ratio for tissue and new blood donors. Residual risk (RR) was calculated as the product of incidence and duration of WP for single donor HBV NAT at 0.058 years (21 days), HCV NAT at 0.008 years (3 days) and HIV NAT at 0.014 (5 days). Between 2013 and 2017, 7886 living surgical bone donors were tested, 16 were positive for markers of HBV, HCV and HIV. HCV had the highest prevalence at 114/100,000 donors. Incidence and RR was highest for HBV at 3.55/100,000-person years and 0.32/100,000 donors (95% CI 0.11/100,000-1.42/100,000). Among 9751 deceased tissue donors tested, 22 were positive for viral markers. HBV had highest prevalence at 174/100,000 donors, and the highest incidence and RR at 8.12/100,000 person years and 0.74/100,000 donors (95% CI 0.08/100,000-2.99/100,000). Using ID NAT, RR of not detecting a HBV, HCV and HIV WP donation among tissue donors is less than 1/100,000 donors. These estimates provide a good starting point for discussing potential risks of viral transmission through tissue transplant with patients., (© 2021. Crown.)

Background: In 2011 in the United Kingdom (UK), excluding Northern Ireland, the deferral of men who have sex with men (MSM) changed from lifetime to 12 months. We describe MSM who donated before and after this to inform further policy reviews., Materials and Methods: Characteristics and sexual behaviours of donors identifying as male from routine surveillance are described. Rates of infections are compared pre- and post-implementation of a 12-month deferral. Donors are compared with screen negative male donors responding to a large-scale survey during 2013/2014., Results: Comparing the five years pre- and post-change, the rate of confirmed positives for markers of HBV, HCV, HIV and syphilis decreased by 6·9% from 14·1 to 13·1/100 000 donations. The rate of recent infections was unchanged (1·72/100 000). Of 22 776 survey responses identifying as male, MSM disclosed sex between men over 12 months ago giving 99·35% compliance among male donors. Two-thirds of the 72 non-compliant MSM reported one to two partners and one-third had no new partners within 12 months. The most commonly reported reason for non-compliance from MSM both positive and negative for infection was 'not important to declare' (37·2% and 40·7%). Test seeking was rare (9·3% and 2·1%)., Conclusion: Compliance with the 12-month MSM deferral policy was very high. The very low rates of infections post-change demonstrated the effectiveness of the policy. These data were an important part of the 2017 review of all sexual behaviour deferrals., (© 2021 Crown Copyright. Vox Sanguinis © 2021 International Society of Blood Transfusion. The article is published with the permission of the Controller of HMSO and the Queen’s Printer for Scotland.)

Background and Objectives: Injecting drug use (IDU), a permanent deferral for blood donors, was included in a review of donor selection criteria completed in 2017. Here, we describe what is known about IDU in blood donors in the United Kingdom (UK)., Materials and Methods: Data were obtained from routine surveillance of donation testing and confirmed positive donors and a 2013/2014 UK survey of behaviour and compliance in screen-negative donors., Results: Between 2009 and 2018, of 22 UK million donations screened, IDU was self-reported at the post-test discussion in 5% (86/1777) of donors with confirmed positive donations. Recent injecting within 12 months was reported in 8 HCV-positive donors, but only in 1/14 donors where it was clear HCV infection had been acquired in the previous 12 months. Of 65 439 survey responders, 25 reported IDU, which when weighted to the donor population gave 99·95% compliance. Most of the 111 donors reporting IDU felt it was not important to their donation, mainly because their injecting was in the past, while three HCV-positive recent injectors reported not sharing needles so presumably felt safe to donate., Conclusion: Compliance with the permanent deferral appeared extremely high with low levels of injecting reported by donors, mainly in the past. This agreed with the low-incident HCV infection observed in UK donors. These data contributed to a recommendation to reduce the deferral to 1 year. Ways of improving compliance in those few donors at current increased risk of infection need to be investigated., (© 2020 International Society of Blood Transfusion.)

Background: Although the need for whole blood is declining, so too are the number of first-time and repeat blood donors. To develop new recruitment and retention strategies, therefore, we need to draw on as wide a variation in blood donor motivations as possible. The primary aim of this study is to draw on a large survey of donors to develop a broad, theoretically instantiated typology of donor motivations to identify new and less common, yet practically important, motivations that have not been previously reported., Study Design and Methods: Using data from the UK Blood Donor Survey run by NHS Blood and Transplant/Public Health England Epidemiology Unit (N = 61 123 donors), we analyze fixed (N = 52 225) and free (N = 8867) responses to develop a more comprehensive typology of blood donor motivations based on theories from the biology, psychology, philosophy, economics, and sociology of altruism., Results: We identified 54 motivations, including a number of newly identified motivations, for blood donations which we organized into 12 superordinate categories (eg, "inspiration via moral elevation," "perceived social closeness," and "fungibility of donations"). These are linked to intervention suggestions such as donating blood in memoriam or donating blood as an alternative to other charitable acts., Conclusion: We present the most comprehensive account of blood donor motivations to-date. This work also offers a structure for coding free-text responses, developing motivational measures, and identifying tangible interventions. Thus, we feel that this is a valuable resource for blood donor researchers, marketers, and policy makers., (© 2020 The Authors. Transfusion published by Wiley Periodicals LLC. on behalf of AABB.)

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., (© 2019 British Blood Transfusion Society.)

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., (© 2019 British Blood Transfusion Society.)

Human immuno virus screening assays have improved in sensitivity over the last 20 years and our data demonstrates that there is no evidence of missed HIV positive window period donations since the introduction of pooled HIV NAT screening. Here we recommend that extensive lookback investigations are not routinely required if the most recent negative donation is negative on individual sample HIV PCR testing., (© 2019 International Society of Blood Transfusion.)

Background: For infectious disease risk assessment among deceased organ donors, pre-donation clinical, microbiological, and behavioral information are reviewed; however, uncertainty may arise due to false negative screening results of recently acquired infections., Method: The burden of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV), and residual risks (RR) of undetected virus was estimated, with the impact of more sensitive screening., Results: For United Kingdom potential deceased organ donors between 2010 and 2014, prevalence of HBsAg was 0.1%, HIV 0.06% and HCV 0.9%, increasing to 25.7% in people who injected drugs (PWID). Incidence, derived from new blood donors, was multiplied by duration of screening assay window periods to give RR per 100 000 donors as 0.43 (95% confidence interval [CI] 0.03-3.99) for HBV, 0.08 (95% CI 0.02-0.21) for HIV, and 5.96 (95% CI 0.82-37.89) for HCV. For PWID, HCV RR was 163.3 (95% CI 22.8-1107.8) compared to 2.76 (95% CI 0.35-17.36) for non-PWID. RR decreased significantly with nucleic acid testing (NAT), and, for HCV, antigen testing had a similar impact., Conclusion: While the burden of HCV risk lies within PWID, these are in small numbers therefore few HCV antigen or NAT tests would be needed to more accurately assess risk., (© 2019 Crown copyright. Transplant Infectious Disease © 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.)

IntroductionHepatitis E virus (HEV), the most common cause of acute hepatitis in many European countries, is transmitted through consumption of processed pork but also via blood transfusion and transplantation. HEV infection can become persistent in immunocompromised individuals.AimWe aimed to determine the incidence and epidemiology of HEV infection in English blood donors since the introduction of donation screening in 2016.MethodsBetween March 2016 and December 2017, 1,838,747 blood donations were screened for HEV RNA. Donations containing HEV RNA were further tested for serological markers, RNA quantification and viral phylogeny. Demographics, travel and diet history were analysed for all infected donors.ResultsWe identified 480 HEV RNA-positive blood donations during the 22-month period, most (319/480; 66%) donors were seronegative. Viral loads ranged from 1 to 3,230,000 IU/ml. All sequences belonged to genotype 3, except one which likely represents a new genotype. Most viraemic donors were over 45 years of age (279/480; 58%), donors aged between 17 and 24 years had a seven-times higher incidence of HEV infection than other donors between March and June 2016 (1:544 donations vs 1:3,830). HEV-infected blood donors were evenly distributed throughout England. Screening prevented 480 HEV RNA-positive blood donations from reaching clinical supply.ConclusionHEV screening of blood donations is a vital step in order to provide safer blood for all recipients, but especially for the immunosuppressed. The unusually high rates of HEV infection in young blood donors may provide some insight into specific risks associated with HEV infection in England.

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., (© 2018 International Society of Blood Transfusion.)

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., (© 2018 International Society of Blood Transfusion.)

Background: Hepatitis E virus (HEV) Genotype 3 (G3) in England comprises two principal phylogenetic groups (Group 1 and Group 2) and can be transmitted by transfusion. Unselected screening identified 79 viremic donors; 76 participated in a follow-up study., Study Design and Methods: Viral RNA dynamics, phylogenetics, and seroconversion were characterized in the donors. Detailed demographic, travel, clinical, and lifestyle questionnaires were undertaken., Results: The majority of viremic individuals (57/79) were seronegative at time of donation but all seroconverted. Viremia was short-lived, with a median of 6.5 weeks to confirmed viral clearance. All infections were acquired in the United Kingdom and were G3, with Group 2 viruses predominating (43/54; 80%). Infection was associated with some clinical symptoms both at and after donation (8/77; 10%). Viral loads and symptoms were more pronounced in Group 1 infections. There was no serologic evidence of reinfection. Donors were more commonly male (p = 0.002); both male and female donors were older than comparator donors. Animal contact was unlikely to be the source of infection. Consumption of chicken and pig meat was common to all infected donors; processed pig meat was most commonly purchased from one particular retail chain., Conclusion: Viremic donors represent primary infection in older members of the community and reflect a widespread zoonotic in the United Kingdom. The two phylogenetic groups of HEV G3 display different pathogenicity and the more common Group 2 appears less adapted to humans. There are no objective demographic criteria that can identify donors at enhanced HEV risk., (© 2016 AABB.)

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., (© 2015 British Blood Transfusion Society.)

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., (© 2015 British Blood Transfusion Society.)

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., (© 2015 British Blood Transfusion Society.)

Background: As populations in the developed world shift toward an older and more ethnically diverse population, the challenges of recruiting and retaining sufficient donors to secure an adequate, safe supply of blood in the future will increase., Study Design and Methods: The study population included all first-time (n = 348,740) and repeat (n = 1,805,255) blood donors and their donations (n = 3,854,460) received by NHS Blood and Transplant during 2010 and 2011. Rates of new and repeat donors per 1000 population were estimated using Office for National Statistics 2011 population estimates. Factors associated with new blood donors returning within 6 months were analyzed using multivariate logistic regression., Results: The majority (87.9%) of donors were white British; 5.5% were unknown; 3.4% white Irish or white other; and 3.2% composed of all other ethnic groups. The median ages of new and repeat donors in 2010 were 28.0 and 45.0 years, respectively, compared to 29.0 and 47.0 years in 2011. Rates of donation varied by ethnicity, ranging from 1.59 per 1000 among Asian Bangladeshi origin, compared to 22.1 per 1000 among white British origin. Approximately two in five (38.4%) new blood donors returned within 6 months and were more likely to be male and of white ethnicity., Conclusions: Blood supply is impacted by numerous factors, including an aging population and an increasing population of migrant communities with lower donation rates. It is therefore critical that changes within the blood donor and wider population are monitored to inform donor recruitment and retention strategies., (© 2014 AABB.)

Background: The prevalence of hepatitis E virus (HEV) genotype 3 infections in the English population (including blood donors) is unknown, but is probably widespread, and the virus has been detected in pooled plasma products. HEV-infected donors have been retrospectively identified through investigation of reported cases of possible transfusion-transmitted hepatitis E. The frequency of HEV transmission by transfusion and its outcome remains unknown. We report the prevalence of HEV RNA in blood donations, the transmission of the virus through a range of blood components, and describe the resulting morbidity in the recipients., Methods: From Oct 8, 2012, to Sept 30, 2013, 225,000 blood donations that were collected in southeast England were screened retrospectively for HEV RNA. Donations containing HEV were characterised by use of serology and genomic phylogeny. Recipients, who received any blood components from these donations, were identified and the outcome of exposure was ascertained., Findings: 79 donors were viraemic with genotype 3 HEV, giving an RNA prevalence of one in 2848. Most viraemic donors were seronegative at the time of donation. The 79 donations had been used to prepare 129 blood components, 62 of which had been transfused before identification of the infected donation. Follow-up of 43 recipients showed 18 (42%) had evidence of infection. Absence of detectable antibody and high viral load in the donation rendered infection more likely. Recipient immunosuppression delayed or prevented seroconversion and extended the duration of viraemia. Three recipients cleared longstanding infection after intervention with ribavirin or alteration in immunosuppressive therapy. Ten recipients developed prolonged or persistent infection. Transaminitis was common, but short-term morbidity was rare; only one recipient developed apparent but clinically mild post-transfusion hepatitis., Interpretation: Our findings suggest that HEV genotype 3 infections are widespread in the English population and in blood donors. Transfusion-transmitted infections rarely caused acute morbidity, but in some immunosuppressed patients became persistent. Although at present blood donations are not screened, an agreed policy is needed for the identification of patients with persistent HEV infection, irrespective of origin, so that they can be offered antiviral therapy., Funding: Public Health England and National Health Service Blood and Transplant., (Copyright © 2014 Hewitt et al. Open Access article distributed under the terms of CC BY-NC-ND. Published by Elsevier Ltd. All rights reserved.)

Background: Hepatitis B virus (HBV) remains the infection most frequently recognized by donation testing in blood donors. It is usually a persistent infection and mostly reflects the country of origin of the donor or the donor's family. There are, however, a minority of acute infections and this study undertook their phylogenetic analysis to determine the likely source of infection., Study Design and Methods: Plasma samples from 11 donors donating between July 2005 and June 2010, whose test results revealed recent infection with hepatitis B, were available for further analysis. Plasma DNA was extracted, amplified, sequenced, and analyzed phylogenetically. Donor and virus characteristics were compared with the overall demography of all hepatitis B-infected donors attending over the same period., Results: Three of the 11 individuals were first-time donors. Nine were male, of whom eight were white British. All had serum markers of very recent infection. Only two indicated known HBV exclusion risk factors at postdonation discussion not declared previously. Genotype A was present in seven, Genotype B in two, and Genotype C in two, contrasting with the pattern in persistently infected persons in the United Kingdom. A single A2 strain was identified in six of the white British male donors, suggesting epidemiologic linkage., Conclusion: Phylogenetic analysis of HBV-infected donors performed in real time can potentially lead to identification of undeclared risk factors that donor health questionnaires may fail to identify., (© 2013 AABB.)

Background: Culture-based systems are currently the preferred means for bacterial screening of platelet (PLT) concentrates. Alternative bacterial detection techniques based on nucleic acid amplification have also been developed but these have yet to be fully evaluated. In this study we evaluate a novel 16S rDNA polymerase chain reaction (PCR) assay and compare its performance with automated culture., Study Design and Methods: A total of 2050 time-expired, 176 fresh, and 400 initial-reactive PLT packs were tested by real-time PCR using broadly reactive 16S primers and a "universal" probe (TaqMan, Invitrogen). PLTs were also tested using a microbial detection system (BacT/ALERT, bioMérieux) under aerobic and anaerobic conditions., Results: Seven of 2050 (0.34%) time-expired PLTs were found repeat reactive by PCR on the initial nucleic acid extract but none of these was confirmed positive on testing frozen second aliquots. BacT/ALERT testing also failed to confirm any time-expired PLTs positive on repeat testing, although 0.24% were reactive on the first test. Three of the 400 "initial-reactive" PLT packs were found by both PCR and BacT/ALERT to be contaminated (Escherichia coli, Listeria monocytogenes, and Streptococcus vestibularis identified) and 14 additional packs were confirmed positive by BacT/ALERT only. In 13 of these cases the contaminating organisms were identified as anaerobic skin or oral commensals and the remaining pack was contaminated with Streptococcus pneumoniae., Conclusion: These results demonstrate that the 16S PCR assay is less sensitive than BacT/ALERT and inappropriate for early testing of concentrates. However, rapid PCR assays such as this may be suitable for a strategy of late or prerelease testing., (© 2013 American Association of Blood Banks.)

Background: In 2010 hepatitis B virus (HBV) was the most frequently detected infection in UK blood donation screening, typically found in first-time, male, chronically infected donors born abroad. To date there has been no comprehensive characterization of the virologic profile of these infections., Study Design and Methods: Epidemiologic and serologic data were collected retrospectively for 344 chronically HBV-infected blood donors identified from July 2005 to June 2010. Additional laboratory testing was carried out to determine the HBV genotype, viral load, and prevalence of clinically significant mutations and to detect hepatitis delta virus (HDV) coinfection., Results: Five HBV genotypes (A-E) were found, Genotypes D (45%), A (20%), and E (20%) were the most prevalent. A strong association was seen between genotype and donor ethnicity (p < 0.001) and between genotype and place of residence (p = 0.006). Clinically significant mutations were observed across hepatitis B surface antigen (17%), basal core promoter (25%) and precore (78%) regions. An antiviral resistance profile was identified in one donor. Evidence of HDV coinfection was found in 2% of donors., Conclusion: The data show the diversity of HBV in asymptomatic chronic infections detected in blood donors in England and North Wales and demonstrates the presence of mutations which may impact on disease. The global nature of these infections and the inability to identify chronically infected donors before donation highlights the importance of using screening assays capable of detecting a broad range of genotypes and mutations. Furthermore, the integration of the virologic and demographic data allows us to more accurately construct a profile of our chronically HBV-infected blood donors., (© 2012 American Association of Blood Banks.)

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%., (© 2013 International Society of Blood Transfusion.)

Background: Maternal obesity is associated with menstrual disorders, infertility and sporadic miscarriages. Recurrent miscarriage (RM) affects at least 1% of couples trying to conceive. In over 50% of cases, the cause of the loss of pregnancy remains unexplained. The aim of this study was to determine the relationship between maternal Body Mass Index (BMI) and future outcomes of pregnancy in couples with "unexplained" RM., Methods and Results: All couples referred to the specialist recurrent miscarriage clinic at St. Mary's Hospital, London, were investigated for an underlying cause. Those with unexplained RM were eligible. Demographic and clinical data were retrieved from a computerised database and medical records. The World Health Organisation (WHO) classification of BMI was used. Univariate analysis demonstrated that BMI, maternal age, number of previous miscarriages and ethnicity were significantly associated with pregnancy outcome. Logistic regression demonstrated that maternal obesity (BMI ≥ 30 kg/m(2)) significantly increased the risk of miscarriage in couples with unexplained RM (OR 1.73; 95% CI 1.06 - 2.83). Asian women with a BMI similar to Caucasian women had a higher risk of a further miscarriage (OR 2.87, 95% CI, 1.52 - 5.39)., Conclusions: Maternal obesity is an independent factor associated with an increased risk of miscarriage in couples with RM. All women with RM should have their BMI recorded at their first clinic visit. The potential effect of weight loss on the outcome of subsequent pregnancies should be assessed in future studies. The increased risk of miscarriage in Asian women needs to be explored further.

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., (© 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.)

Oral candidosis is a significant cause of morbidity in patients with advanced cancer. The objectives of the study were to determine the epidemiology, etiology, clinical features, and microbiological aspects of oral candidosis among community-based patients. The subjects were recruited from hospice day centers in England. The clinical component involved completion of a study questionnaire, assessment of performance status, clinical examination of the oral cavity, measurement of unstimulated whole salivary flow rate, measurement of stimulated whole salivary flow rate, and performance of an oral rinse. Oral swabs were taken from subjects with appearances indicative of oral candidosis. The laboratory component involved standard procedures to isolate, enumerate, and identify yeasts from the clinical specimens. Three hundred ninety patients participated in the study. Two hundred seventy-two (70%) patients had oral yeast carriage, and 51 (13%) patients had combined clinical and microbiological evidence of oral candidosis. On univariate analysis, the presence of oral candidosis was associated with poor Eastern Cooperative Oncology Group performance status, presence of a denture, usage of a systemic corticosteroid, the severity of xerostomia, a low unstimulated whole salivary flow rate, and a low stimulated whole salivary flow rate. Multivariate analysis identified poor Eastern Cooperative Oncology Group performance status, presence of a denture, usage of a systemic corticosteroid, and the severity of xerostomia as being independently associated with the presence of oral candidosis. Oral candidosis is relatively common in community-based patients with advanced cancer. Hence, such patients should be screened for oral candidosis and should also be screened for reversible factors that predispose to oral candidosis, such as poor dental hygiene and salivary gland dysfunction.

MDPB, 12-methacryloyloxydodecylpyridinium bromide, was tested for its ability to inhibit the growth of organisms associated with active root caries lesions and to modify the growth characteristics of these organisms at sub-MICs. MICs and MBCs of MDPB for independent isolates (n=5) of the following taxa: Streptococcus mutans, Streptococcus oralis, Streptococcus salivarius, Actinomyces naeslundii, Actinomyces israelii, Actinomyces gerensceriae, Actinomyces odontolyticus, Lactobacillus spp., and Candida albicans were determined, and the effects at sub-MIC on microbial growth kinetics were assessed. All isolates were sensitive to inhibition by MDPB. The median MICs and MBCs of MDPB for these organisms were in the range of 3.13 to 25.0 microg/ml and 6.25 to 50.0 microg/ml, respectively. As for the influence of pH, inhibition was sensitive to acidic pH. Even at sub-MICs, the growth of all strains, measured as cell yield and doubling time, was significantly reduced. Based on the results of this study, MDPB exhibited the potential to inhibit the growth of microbiota associated with active root caries lesions.

The objectives of the study were to determine the epidemiology, aetiology, clinical features and microbiological aspects of oral candidosis in a cohort of cancer patients receiving specialist palliative care. One hundred and twenty patients participated in the study. Seventy-nine (66%) of the patients had microbiological evidence of oral yeast carriage, whilst 36 (30%) of the patients had combined clinical and microbiological evidence of oral candidosis. Oral candidosis was associated with a poor performance status, the presence of xerostomia, and the presence of dentures; oral candidosis was not associated with the use of oral/parenteral antibiotics, or the use of oral/parenteral corticosteroids. Candida albicans was the predominant organism isolated from the oral swabs of patients with oral candidosis. However, non-C. albicans species were the predominant organism in 25% cases, and a contributing organism in a further 19% cases.

The predominant surface proteins of biofilm and planktonic Actinomyces naeslundii, a primary colonizer of the tooth surface, were examined. Seventy-nine proteins (the products of 52 genes) were identified in biofilm cells, and 30 of these, including adhesins, chaperones, and stress-response proteins, were significantly up-regulated relative to planktonic cells.

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., (Copyright (c) 2005 S. Karger AG, Basel.)

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.

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., (Copyright 2005 S. Karger AG, Basel.)

The hypotheses that raw fruits, whether whole or pulped, were cleared rapidly from the mouth and that the sugars in the whole and pulped fruits are fermented with equal efficiency to acids by the oral microflora were tested in this study. Groups of 7-9 adult subjects chewed 10 g of raw, whole or pulped fruit (apple, banana, orange, pear and pineapple) for 1 min and whole, unstimulated saliva samples were collected during the following 60-min interval. Each saliva sample was assayed for the concentrations of fruit-derived sugars (glucose, fructose and sucrose), fruit-derived acids (malic and citric) and acids which may be produced as a result of bacterial fermentation (acetic, lactic, formic and succinic). We found the fruit-derived sugars were rapidly cleared from the mouth (within 5 min). The major bacterially produced acids were lactic and succinic, which reached maximum concentrations in the 5-min sample. There was no significant difference, within a fruit, in the salivary levels of any of the sugars or acids between the raw whole or raw pulped forms. In light of these findings it seems unwise to assume that fruits may be consumed without consideration of their acidogenic potential., (Copyright 2004 S. Karger AG, Basel)

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.

The genotypic diversity of Actinomyces naeslundii genospecies 2 (424 isolates) and Streptococcus oralis (446 isolates) strains isolated from two sound approximal sites in all subjects who were either caries active (seven subjects) or caries free (seven subjects) was investigated by using the repetitive extragenic palindromic PCR. The plaque from the caries-active subjects harbored significantly greater proportions of mutans streptococci and lactobacilli and a smaller proportion of A. naeslundii organisms than the plaque sampled from the caries-free subjects. These data confirmed that the sites of the two groups of subjects were subjected to different environmental stresses, probably determined by the prevailing or fluctuating acidic pH values. We tested the hypothesis that the microfloras of the sites subjected to greater stresses (the plaque samples from the caries-active subjects) would exhibit reduced genotypic diversity since the sites would be less favorable. We found that the diversity of A. naeslundii strains did not change (chi2 = 0.68; P = 0.41) although the proportional representation of A. naeslundii was significantly reduced (P < 0.05). Conversely, the diversity of the S. oralis strains increased (chi2 = 11.71; P = 0.0006) and the proportional representation of S. oralis did not change. We propose that under these environmental conditions the diversity and number of niches within the oral biofilm that could be exploited by S. oralis increased, resulting in the increased genotypic diversity of this species. Apparently, A. naeslundii was not able to exploit the new niches since the prevailing conditions within the niches may have been deleterious and not supportive of its proliferation. These results suggest that environmental stress may modify a biofilm such that the diversity of the niches is increased and that these niches may be successfully exploited by some, but not necessarily all, members of the microbial community.

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., (Copyright 2002 Elsevier Science Ltd.)

Objectives: To determine the effects of a medicated chewing gum on the oral health of frail older people., Design: A controlled, double-blind trial using three groups based on random allocation of residential homes., Setting: Sixteen residential homes in West Hertfordshire, England., Participants: One hundred eleven dentate subjects aged 60 and older who completed the 12-month study., Intervention: Subjects were assigned to a chlorhexidine acetate/xylitol gum (ACHX) group, a xylitol gum (X) group, or a no-gum (N) group. Subjects in the gum groups chewed two pellets for 15 minutes twice daily for 12 months., Measurements: Primary outcome measures were salivary flow rate, denture debris score, prevalence of angular cheilitis, and denture stomatitis; secondary outcome measures were salivary levels of caries-associated microorganisms. A single examiner, who was blinded to group allocation, made all measurements at baseline before gum usage and at subsequent examinations after 3, 6, 9, and 12 months. Separate analyses were performed for subjects with dentures., Results: Subjects in the three groups were similar in most of their baseline characteristics. The stimulated whole saliva flow rate +/- standard deviation increased significantly for the ACHX (1.4 +/- 0.7 mL/min) and X (1.6 +/- 0.9 mL/min) groups (P <.01) over baseline (ACHX = 0.9 +/- 0.6 mL/min, X = 0.8 +/- 0.6 mL/min) and N group levels (0.6 +/- 0.9 mL/min). The levels of mutans streptococci, lactobacilli, and yeasts significantly increased (P <.05) in the X and N groups. Denture debris status was significantly lower in the ACHX and X groups than at baseline or in the N group (P <.01). The reductions of 91% and 75% in denture stomatitis and angular cheilitis prevalence, respectively, that occurred in the ACHX group were significantly greater (P <.01) than the reductions in the X group (denture stomatitis 62%, angular cheilitis 43%). Prevalence of denture stomatitis and angular cheilitis were not significantly changed in the N group., Conclusion: The use of a medicated chewing gum significantly improved oral health in older occupants of residential homes. Chewing gums should be considered as a potential adjunct to other oral hygiene procedures in older subjects.