Detection of SARS-CoV-2-specific mucosal antibodies in saliva following concomitant COVID-19 and influenza vaccination in the ComFluCOV trial

The ComFluCOV trial randomized 679 participants to receive an age-appropriate influenza vaccine, or placebo, alongside their second COVID-19 vaccine. Concomitant administration was shown to be safe, and to preserve systemic immune responses to both vaccines. Here we report on a secondary outcome of the trial investigating SARS-CoV-2-specific mucosal antibody responses. Anti-spike IgG and IgA levels in saliva were measured with in-house ELISAs. Concomitant administration of an influenza vaccine did not affect salivary anti-spike IgG positivity rates to Pfizer/BioNTech BNT162b2 (99.1 cf. 95.6%), or AstraZeneca ChAdOx1 (67.8% cf. 64.9%), at 3-weeks post-vaccination relative to placebo. Furthermore, saliva IgG positively correlated with serum titres highlighting the potential utility of saliva for assessing differences in immunogenicity in future vaccine studies. Mucosal IgA was not detected in response to either COVID-19 vaccine, reinforcing the need for novel vaccines capable of inducing sterilising immunity or otherwise reducing transmission. The trial is registered as ISRCTN 14391248.

Working under short timescales to deliver a national trial: a case study of the ComFluCOV trial from a statistician's perspective

BACKGROUND

In early 2021, the Department of Health and Social Care in the UK called for research on the safety and immunogenicity of concomitant administration of COVID-19 and influenza vaccines. Co-administration of these vaccines would facilitate uptake and reduce the number of healthcare visits required. The ComFluCOV trial was designed to deliver the necessary evidence in time to inform the autumn (September-November) 2021 vaccination policy. This paper presents the statistical methodology applied to help successfully deliver the trial results in 6 months.

METHODS

ComFluCOV was a parallel-group multicentre randomised controlled trial managed by the Bristol Trials Centre. Two study statisticians, supported by a senior statistician, worked together on all statistical tasks. Tools were developed to aid the pre-screening process. Automated data monitoring reports of clinic data and electronic diaries were produced daily and reviewed by the trial team and feedback provided to sites. Analyses were performed independently in parallel, and derivations and results of all outcomes were compared.

RESULTS

Set-up was achieved in less than a month, and 679 participants were recruited over 8 weeks. A total of 537 [at least] daily reports outlining recruitment, protocol adherence, and data quality, and 695 daily reports of participant electronic diaries identifying any missed diary entries and adverse events were produced over a period of 16 weeks. A preliminary primary outcome analysis of validated data was reported to the Department of Health and Social Care in May 2021. The database was locked 6 weeks after the final participant follow-up and final analyses completed 3 weeks later. A pre-print publication was submitted within 14 days of the results being made available. The results were reported 6 months after first discussions about the trial.

CONCLUSION

The statistical methodologies implemented in ComFluCOV helped to deliver the study in the timescale set. Working in a new clinical area to tight timescales was challenging. Having two statisticians working together on the study provided a quality assurance process that enabled analyses to be completed efficiently and ensured data were interpreted correctly. Processes developed could be applied to other studies to maximise quality, reduce the risk of errors, and overall provide enhanced validation methods.

TRIAL REGISTRATION

ISRCTN14391248, registered on 30 March 2021.

Delivering COVID-19 vaccine trials at speed: the implementation of a phase IV UK multi-centre randomised controlled trial to determine safety and immunogenicity of COVID-19 vaccines co-administered with seasonal influenza vaccines (ComFluCOV)

BACKGROUND

In February 2021, the UK Department of Health and Social Care sought evidence on the safety and immunogenicity of COVID-19 and influenza vaccine co-administration to inform the 2021/2022 influenza vaccine policy. Co-administration could support vaccine uptake and reduce healthcare appointments. ComFluCOV was a randomised controlled trial designed to provide this evidence. This report outlines the methods used to deliver the trial in 6 months to answer an urgent public health question as part of the COVID-19 pandemic response.

METHODS

ComFluCOV was commissioned by the Department of Health and Social Care and was managed by the Bristol Trials Centre, a UK-registered clinical trials unit. It was classed as an Urgent Public Health trial which facilitated fast-track regulatory approvals. Trial materials and databases were developed using in-house templates and those used in other COVID-19 vaccine trials. Participants were recruited by advertising, and via a trial website. Electronic trial systems enabled daily review of participant data. Weekly virtual meetings were held with stakeholders and trial sites.

RESULTS

ComFluCOV was delivered within 6 months from inception to reporting, and trial milestones to inform the Department of Health and Social Care policy were met. Set-up was achieved within 1 month. Regulators provided expedited reviews, with feedback ahead of submission. Recruitment took place at 12 sites. Over 380 site staff were trained. Overall, 679 participants were recruited in two months. The final report to the Department of Health and Social Care was submitted in September 2021, following a preliminary safety report in May 2021. Trial results have been published.

CONCLUSION

The rapid delivery of ComFluCOV was resource intensive. It was made possible in part due to a unique set of circumstances created by the pandemic situation including measures put in place to support urgent public health research and public support for COVID-19 vaccine research. Elements of the trial could be adopted to increase efficiency in 'non-pandemic' situations including working with a clinical trials unit to enable immediate mobilisation of a team of experienced researchers, greater sharing of resources between clinical trials units, use of electronic trial systems and virtual meetings.

TRIAL REGISTRATION

ISRCTN14391248, submitted on 17/03/2021. Registered on 30/03/2021.

Safety and immunogenicity against ancestral, Delta and Omicron virus variants following a booster dose of an inactivated whole-virus COVID-19 vaccine (VLA2001): Interim analysis of an open-label extension of the randomized, controlled, phase 3 COV-COMPARE trial

OBJECTIVES

Booster doses for COVID-19 vaccinations have been shown to amplify the waning immune response after primary vaccination and to enhance protection against emerging variants of concern (VoCs). Here, we aimed to assess the immunogenicity and safety of a booster dose of an inactivated whole-virus COVID-19 vaccine (VLA2001) after primary vaccination with 2 doses of either VLA2001 or ChAdOx1-S (Oxford-Astra Zeneca), including the cross-neutralization capacity against the Delta and Omicron VoCs.

METHODS

This interim analysis of an open-label extension of a randomized, controlled phase 3 trial assessed a single booster dose of an inactivated whole-virus COVID-19 vaccine (VLA2001) in healthy or medically stable adults aged 18 years and above, recruited in 21 clinical sites in the UK, who had previously received two doses of either VLA2001 or ChAdOx1-S. Safety outcomes were frequency and severity of solicited injection site and systemic reactions within 7 days after booster vaccination as well as frequency and severity of any unsolicited adverse events (AE) after up to 6 months. Immunogenicity outcomes were the immune response to ancestral SARS-CoV-2 assessed 14 days post booster expressed as geometric mean titres (GMT), GMT fold ratios and seroconversion of specific neutralizing antibodies and S-protein binding IgG antibodies. Immunogenicity against the Delta and Omicron VoCs was assessed as a post-hoc outcome with a pseudovirus neutralization antibody assay. This study is registered with ClinicalTrials.gov, NCT04864561, and is ongoing.

RESULTS

A booster dose of VLA2001 was administered to 958 participants, of whom 712 had been primed with VLA2001, and 246 with ChAdOx1-S. Within 7 days following these booster doses, 607 (63.4%) participants reported solicited injection site reactions, and 487 (50.8%) reported solicited systemic reactions. Up to 14 days post booster, 751 (78.4%) participants reported at least one adverse event. The tolerability profile of a booster dose of VLA2001 was similar in VLA2001-primed and ChAdOx1-S-primed participants. In VLA2001-primed participants, the GMT (95% CI) of neutralizing antibodies increased from 32.5 (22.8, 46.3) immediately before to 521.5 (413.0, 658.6) 2 weeks after administration of the booster dose, this corresponds to a geometric mean fold rise (GMFR) of 27.7 (20.0, 38.5). Compared to 2 weeks after the second priming dose, the GMFR was 3.6 (2.8, 4.7). In the ChAdOx1-S primed group, the GMT (95% CI) of neutralizing antibodies increased from 65.8 (43.9, 98.4) immediately before to 188.3 (140.3, 252.8) 2 weeks after administration of the booster dose, a geometric mean fold rise (GMFR) of 3.0 (2.2, 4.0). Compared to 2 weeks after the second priming dose, the GMFR was 1.6 (1.1, 2.2). For S-protein binding IgG antibodies, the pre- versus post-booster GMT fold ratio (95% CI) was 34.6 (25.0, 48.0) in the VLA2001-primed group and 4.0 (3.0, 5.2) in the ChAdOx1-S-primed group. Compared to 2 weeks after the second priming dose, the GMT fold rise of IgG antibodies was 3.8 (3.2, 4.6) in the VLA2001-primed group and 1.2 (0.9, 1.6) in the ChAdOx1-S-primed group. The GMT against Delta (B.1.617.2) and Omicron (BA.4/5) increased from 4.2 to 260, and from 2.7 to 56.7, respectively, when boosting subjects previously primed with VLA2001. Following the boost, 97% of subjects primed with VLA2001 had detectable Delta- and 94% Omicron-neutralizing antibodies. In subjects primed with ChAdOx1-S, the GMT against Delta and Omicron titres increased from 9.1 to 92.5, and from 3.6 to 12.3, respectively. After boosting, 99% of subjects primed with ChAdOx1-S had detectable Delta- and 70% Omicron-neutralizing antibodies. In both VLA2001 and ChAdOx1-S primed subjects, the additional VLA2001 dose boosted T cell responses against SARS-CoV-2 antigens to levels above those observed before the booster dose.

CONCLUSION

A booster dose of VLA2001 was safe and well tolerated after primary immunization with VLA2001 and ChAdOx1-S. The tolerability of a booster dose of VLA2001 was similar to the favourable profile observed after the first and second priming doses. Both in a homologous and a heterologous setting, boosting resulted in higher neutralizing antibody titres than after primary immunization and significant increases in cross-neutralization titres against Delta and Omicron were observed after the booster dose. These data support the use of VLA2001 in booster programmes in ChadOx1-S primed groups.

Prolonged T-cell activation and long COVID symptoms independently associate with severe COVID-19 at 3 months

Coronavirus disease-19 (COVID-19) causes immune perturbations which may persist long term, and patients frequently report ongoing symptoms for months after recovery. We assessed immune activation at 3-12 months post hospital admission in 187 samples from 63 patients with mild, moderate, or severe disease and investigated whether it associates with long COVID. At 3 months, patients with severe disease displayed persistent activation of CD4+ and CD8+ T-cells, based on expression of HLA-DR, CD38, Ki67, and granzyme B, and elevated plasma levels of interleukin-4 (IL-4), IL-7, IL-17, and tumor necrosis factor-alpha (TNF-α) compared to mild and/or moderate patients. Plasma from severe patients at 3 months caused T-cells from healthy donors to upregulate IL-15Rα, suggesting that plasma factors in severe patients may increase T-cell responsiveness to IL-15-driven bystander activation. Patients with severe disease reported a higher number of long COVID symptoms which did not however correlate with cellular immune activation/pro-inflammatory cytokines after adjusting for age, sex, and disease severity. Our data suggests that long COVID and persistent immune activation may correlate independently with severe disease.

Safety and immunogenicity of the inactivated whole-virus adjuvanted COVID-19 vaccine VLA2001: A randomized, dose escalation, double-blind phase 1/2 clinical trial in healthy adults

OBJECTIVES

We aimed to evaluate the safety and optimal dose of a novel inactivated whole-virus adjuvanted vaccine against SARS-CoV-2: VLA2001.

METHODS

We conducted an open-label, dose-escalation study followed by a double-blind randomized trial using low, medium and high doses of VLA2001 (1:1:1). The primary safety outcome was the frequency and severity of solicited local and systemic reactions within 7 days after vaccination. The primary immunogenicity outcome was the geometric mean titre (GMT) of neutralizing antibodies against SARS-CoV-2 two weeks after the second vaccination. The study is registered as NCT04671017.

RESULTS

Between December 16, 2020, and June 3, 2021, 153 healthy adults aged 18-55 years were recruited in the UK. Overall, 81.7% of the participants reported a solicited AE, with injection site tenderness (58.2%) and headache (46.4%) being the most frequent. Only 2 participants reported a severe solicited event. Up to day 106, 131 (85.6%) participants had reported any AE. All observed incidents were transient and non-life threatening in nature. Immunogenicity measured at 2 weeks after completion of the two-dose priming schedule, showed significantly higher GMTs of SARS-CoV-2 neutralizing antibody titres in the highest dose group (GMT 545.6; 95% CI: 428.1, 695.4) which were similar to a panel of convalescent sera (GMT 526.9; 95% CI: 336.5, 825.1). Seroconversion rates of neutralizing antibodies were also significantly higher in the high-dose group (>90%) compared to the other dose groups. In the high dose group, antigen-specific IFN-γ expressing T-cells reactive against the S, M and N proteins were observed in 76, 36 and 49%, respectively.

CONCLUSIONS

VLA2001 was well tolerated in all tested dose groups, and no safety signal of concern was identified. The highest dose group showed statistically significantly stronger immunogenicity with similar tolerability and safety, and was selected for phase 3 clinical development.

Incidental findings in UK healthy volunteers screened for a COVID-19 vaccine trial

The safety of novel therapeutics and vaccines are typically assessed in early phase clinical trials involving "healthy volunteers." Abnormalities in such individuals can be difficult to interpret and may indicate previously unrecognized medical conditions. The frequency of incidental findings (IFs) in healthy volunteers who attend for clinical trial screening is unclear. To assess this, we retrospectively analyzed data for 1838 "healthy volunteers" screened for enrolment in a UK multicenter, phase I/II severe acute respiratory syndrome-coronavirus 2 (SARS-COV-2) vaccine trial. Participants were predominantly White (89.7%, 1640/1828) with a median age of 34 years (interquartile range [IQR] = 27-44). There were 27.7% of participants (510/1838) who had at least one IF detected. The likelihood of identifying evidence of a potential, new blood-borne virus infection was low (1 in 238 participants) compared with identification of an elevated alanine transaminase (ALT; 1 in 17 participants). A large proportion of participants described social habits that could impact negatively on their health; 21% consumed alcohol in excess, 10% were current smokers, 11% described recreational drug use, and only 48% had body weight in the ideal range. Our data demonstrate that screening prior to enrollment in early phase clinical trials identifies a range of IFs, which should inform discussion during the consent process. Greater clarity is needed to ensure an appropriate balance is struck between early identification of medical problems and avoidance of exclusion of volunteers due to spurious or physiological abnormalities. Debate should inform the role of the trial physician in highlighting and advising about unhealthy social habits.

Immunogenicity, safety, and reactogenicity of heterologous COVID-19 primary vaccination incorporating mRNA, viral-vector, and protein-adjuvant vaccines in the UK (Com-COV2): a single-blind, randomised, phase 2, non-inferiority trial

BACKGROUND

Given the importance of flexible use of different COVID-19 vaccines within the same schedule to facilitate rapid deployment, we studied mixed priming schedules incorporating an adenoviral-vectored vaccine (ChAdOx1 nCoV-19 [ChAd], AstraZeneca), two mRNA vaccines (BNT162b2 [BNT], Pfizer-BioNTech, and mRNA-1273 [m1273], Moderna) and a nanoparticle vaccine containing SARS-CoV-2 spike glycoprotein and Matrix-M adjuvant (NVX-CoV2373 [NVX], Novavax).

METHODS

Com-COV2 is a single-blind, randomised, non-inferiority trial in which adults aged 50 years and older, previously immunised with a single dose of ChAd or BNT in the community, were randomly assigned (in random blocks of three and six) within these cohorts in a 1:1:1 ratio to receive a second dose intramuscularly (8-12 weeks after the first dose) with the homologous vaccine, m1273, or NVX. The primary endpoint was the geometric mean ratio (GMR) of serum SARS-CoV-2 anti-spike IgG concentrations measured by ELISA in heterologous versus homologous schedules at 28 days after the second dose, with a non-inferiority criterion of the GMR above 0·63 for the one-sided 98·75% CI. The primary analysis was on the per-protocol population, who were seronegative at baseline. Safety analyses were done for all participants who received a dose of study vaccine. The trial is registered with ISRCTN, number 27841311.

FINDINGS

Between April 19 and May 14, 2021, 1072 participants were enrolled at a median of 9·4 weeks after receipt of a single dose of ChAd (n=540, 47% female) or BNT (n=532, 40% female). In ChAd-primed participants, geometric mean concentration (GMC) 28 days after a boost of SARS-CoV-2 anti-spike IgG in recipients of ChAd/m1273 (20 114 ELISA laboratory units [ELU]/mL [95% CI 18 160 to 22 279]) and ChAd/NVX (5597 ELU/mL [4756 to 6586]) was non-inferior to that of ChAd/ChAd recipients (1971 ELU/mL [1718 to 2262]) with a GMR of 10·2 (one-sided 98·75% CI 8·4 to ∞) for ChAd/m1273 and 2·8 (2·2 to ∞) for ChAd/NVX, compared with ChAd/ChAd. In BNT-primed participants, non-inferiority was shown for BNT/m1273 (GMC 22 978 ELU/mL [95% CI 20 597 to 25 636]) but not for BNT/NVX (8874 ELU/mL [7391 to 10 654]), compared with BNT/BNT (16 929 ELU/mL [15 025 to 19 075]) with a GMR of 1·3 (one-sided 98·75% CI 1·1 to ∞) for BNT/m1273 and 0·5 (0·4 to ∞) for BNT/NVX, compared with BNT/BNT; however, NVX still induced an 18-fold rise in GMC 28 days after vaccination. There were 15 serious adverse events, none considered related to immunisation.

INTERPRETATION

Heterologous second dosing with m1273, but not NVX, increased transient systemic reactogenicity compared with homologous schedules. Multiple vaccines are appropriate to complete primary immunisation following priming with BNT or ChAd, facilitating rapid vaccine deployment globally and supporting recognition of such schedules for vaccine certification.

FUNDING

UK Vaccine Task Force, Coalition for Epidemic Preparedness Innovations (CEPI), and National Institute for Health Research. NVX vaccine was supplied for use in the trial by Novavax.

Safety and immunogenicity of concomitant administration of COVID-19 vaccines (ChAdOx1 or BNT162b2) with seasonal influenza vaccines in adults in the UK (ComFluCOV): a multicentre, randomised, controlled, phase 4 trial

BACKGROUND

Concomitant administration of COVID-19 and influenza vaccines could reduce burden on health-care systems. We aimed to assess the safety of concomitant administration of ChAdOx1 or BNT162b2 plus an age-appropriate influenza vaccine.

METHODS

In this multicentre, randomised, controlled, phase 4 trial, adults in receipt of a single dose of ChAdOx1 or BNT162b2 were enrolled at 12 UK sites and randomly assigned (1:1) to receive concomitant administration of either an age-appropriate influenza vaccine or placebo alongside their second dose of COVID-19 vaccine. 3 weeks later the group who received placebo received the influenza vaccine, and vice versa. Participants were followed up for 6 weeks. The influenza vaccines were three seasonal, inactivated vaccines (trivalent, MF59C adjuvanted or a cellular or recombinant quadrivalent vaccine). Participants and investigators were masked to the allocation. The primary endpoint was one or more participant-reported solicited systemic reactions in the 7 days after first trial vaccination(s), with a difference of less than 25% considered non-inferior. Analyses were done on an intention-to-treat basis. Local and unsolicited systemic reactions and humoral responses were also assessed. The trial is registered with ISRCTN, ISRCTN14391248.

FINDINGS

Between April 1 and June 26, 2021, 679 participants were recruited to one of six cohorts, as follows: 129 ChAdOx1 plus cellular quadrivalent influenza vaccine, 139 BNT162b2 plus cellular quadrivalent influenza vaccine, 146 ChAdOx1 plus MF59C adjuvanted, trivalent influenza vaccine, 79 BNT162b2 plus MF59C adjuvanted, trivalent influenza vaccine, 128 ChAdOx1 plus recombinant quadrivalent influenza vaccine, and 58 BNT162b2 plus recombinant quadrivalent influenza vaccine. 340 participants were assigned to concomitant administration of influenza and a second dose of COVID-19 vaccine at day 0 followed by placebo at day 21, and 339 participants were randomly assigned to concomitant administration of placebo and a second dose of COVID-19 vaccine at day 0 followed by influenza vaccine at day 21. Non-inferiority was indicated in four cohorts, as follows: ChAdOx1 plus cellular quadrivalent influenza vaccine (risk difference for influenza vaccine minus placebos -1·29%, 95% CI -14·7 to 12·1), BNT162b2 plus cellular quadrivalent influenza vaccine (6·17%, -6·27 to 18·6), BNT162b2 plus MF59C adjuvanted, trivalent influenza vaccine (-12·9%, -34·2 to 8·37), and ChAdOx1 plus recombinant quadrivalent influenza vaccine (2·53%, -13·3 to 18·3). In the other two cohorts, the upper limit of the 95% CI exceeded the 0·25 non-inferiority margin (ChAdOx1 plus MF59C adjuvanted, trivalent influenza vaccine 10·3%, -5·44 to 26·0; BNT162b2 plus recombinant quadrivalent influenza vaccine 6·75%, -11·8 to 25·3). Most systemic reactions to vaccination were mild or moderate. Rates of local and unsolicited systemic reactions were similar between the randomly assigned groups. One serious adverse event, hospitalisation with severe headache, was considered related to the trial intervention. Immune responses were not adversely affected.

INTERPRETATION

Concomitant vaccination with ChAdOx1 or BNT162b2 plus an age-appropriate influenza vaccine raises no safety concerns and preserves antibody responses to both vaccines. Concomitant vaccination with both COVID-19 and influenza vaccines over the next immunisation season should reduce the burden on health-care services for vaccine delivery, allowing for timely vaccine administration and protection from COVID-19 and influenza for those in need.

FUNDING

National Institute for Health Research Policy Research Programme.

Safety and immunogenicity of heterologous versus homologous prime-boost schedules with an adenoviral vectored and mRNA COVID-19 vaccine (Com-COV): a single-blind, randomised, non-inferiority trial

BACKGROUND

Use of heterologous prime-boost COVID-19 vaccine schedules could facilitate mass COVID-19 immunisation. However, we have previously reported that heterologous schedules incorporating an adenoviral vectored vaccine (ChAdOx1 nCoV-19, AstraZeneca; hereafter referred to as ChAd) and an mRNA vaccine (BNT162b2, Pfizer-BioNTech; hereafter referred to as BNT) at a 4-week interval are more reactogenic than homologous schedules. Here, we report the safety and immunogenicity of heterologous schedules with the ChAd and BNT vaccines.

METHODS

Com-COV is a participant-blinded, randomised, non-inferiority trial evaluating vaccine safety, reactogenicity, and immunogenicity. Adults aged 50 years and older with no or well controlled comorbidities and no previous SARS-CoV-2 infection by laboratory confirmation were eligible and were recruited at eight sites across the UK. The majority of eligible participants were enrolled into the general cohort (28-day or 84-day prime-boost intervals), who were randomly assigned (1:1:1:1:1:1:1:1) to receive ChAd/ChAd, ChAd/BNT, BNT/BNT, or BNT/ChAd, administered at either 28-day or 84-day prime-boost intervals. A small subset of eligible participants (n=100) were enrolled into an immunology cohort, who had additional blood tests to evaluate immune responses; these participants were randomly assigned (1:1:1:1) to the four schedules (28-day interval only). Participants were masked to the vaccine received but not to the prime-boost interval. The primary endpoint was the geometric mean ratio (GMR) of serum SARS-CoV-2 anti-spike IgG concentration (measured by ELISA) at 28 days after boost, when comparing ChAd/BNT with ChAd/ChAd, and BNT/ChAd with BNT/BNT. The heterologous schedules were considered non-inferior to the approved homologous schedules if the lower limit of the one-sided 97·5% CI of the GMR of these comparisons was greater than 0·63. The primary analysis was done in the per-protocol population, who were seronegative at baseline. Safety analyses were done among participants receiving at least one dose of a study vaccine. The trial is registered with ISRCTN, 69254139.

FINDINGS

Between Feb 11 and Feb 26, 2021, 830 participants were enrolled and randomised, including 463 participants with a 28-day prime-boost interval, for whom results are reported here. The mean age of participants was 57·8 years (SD 4·7), with 212 (46%) female participants and 117 (25%) from ethnic minorities. At day 28 post boost, the geometric mean concentration of SARS-CoV-2 anti-spike IgG in ChAd/BNT recipients (12 906 ELU/mL) was non-inferior to that in ChAd/ChAd recipients (1392 ELU/mL), with a GMR of 9·2 (one-sided 97·5% CI 7·5 to ∞). In participants primed with BNT, we did not show non-inferiority of the heterologous schedule (BNT/ChAd, 7133 ELU/mL) against the homologous schedule (BNT/BNT, 14 080 ELU/mL), with a GMR of 0·51 (one-sided 97·5% CI 0·43 to ∞). Four serious adverse events occurred across all groups, none of which were considered to be related to immunisation.

INTERPRETATION

Despite the BNT/ChAd regimen not meeting non-inferiority criteria, the SARS-CoV-2 anti-spike IgG concentrations of both heterologous schedules were higher than that of a licensed vaccine schedule (ChAd/ChAd) with proven efficacy against COVID-19 disease and hospitalisation. Along with the higher immunogenicity of ChAd/BNT compared with ChAD/ChAd, these data support flexibility in the use of heterologous prime-boost vaccination using ChAd and BNT COVID-19 vaccines.

FUNDING

UK Vaccine Task Force and National Institute for Health Research.

Building capacity and ensuring equity in clinical trials during the COVID-19 pandemic

e13598

Background: The impact on cancer outcomes from the Covid-19 pandemic has yet to be determined. Concerns persist on screening, delays in diagnosis, treatment interruptions and outcomes of infection in the immunosuppressed. The need for agile working has been exemplified by establishment of Nightingale Hospitals, staff redeployment and sudden integration of virtual consultations into clinical working. With most cancer clinical trials halted, recruitment into COVID-19 research became essential and embedded into the everyday. Here we present how rapid implementation of COVID-19 randomised clinical trials within an NHS organisation during the pandemic was achieved. Methods: A COVID-19 senior facilitation committee was set up to provide oversight, maximise staff capacity and resource and prioritise studies. Specific strategies to maximise access and clinical trials recruitment for patients including children and those with solid tumours were designed. These included presence of a research nurse at clinical ward rounds and team meetings, the promotion of protocol and informed consent training to all including doctors in the acute settings and weekly research meetings to share-best practice. Reflecting on learnings from this time provide an opportunity to consider how we adjust working for our patients in the future. Results: The integration of research into the everyday working of clinical teams looking after patients with COVID-19 has become the norm. The provision of protocol and informed consent training for all levels of staff and the consideration of all patients for trials during clinical ward rounds and multi-disciplinary meetings, have ensured access to trials has become embedded. The integration of research nurses working, upskilling and prompting clinical colleagues has ensured equity of access and provided a research presence and focus during the busy clinical day. The adoption of cross-disciplinary working, sharing best practice and a culture of commitment and support to the trials ensures no patient is denied the opportunity to participate. Three RTCs opened over 7 weeks. At one site 1904 patients were screened for one of the randomised-controlled trials and over 18% of these patients (351) were recruited and 175 patients declined. Conclusions: The pandemic has had a devastating impact across the UK. However, a coordinated and collaborative multi-disciplinary approach has supported high recruitment and equity of access for patients into COVID-19 trials. Learnings from this work may lead to embedding clinical trials and access to translational research for cancer patients in the future as we recover from the full impact of the pandemic. COVID-19 research has demonstrated how increased recruitment accelerates access and implementation of new innovations and novel drug combinations.The full impact of improved access to cancer research in the future during COVID recovery is worthy of more research.

Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 variant of concern 202012/01 (B.1.1.7): an exploratory analysis of a randomised controlled trial

BACKGROUND

A new variant of SARS-CoV-2, B.1.1.7, emerged as the dominant cause of COVID-19 disease in the UK from November, 2020. We report a post-hoc analysis of the efficacy of the adenoviral vector vaccine, ChAdOx1 nCoV-19 (AZD1222), against this variant.

METHODS

Volunteers (aged ≥18 years) who were enrolled in phase 2/3 vaccine efficacy studies in the UK, and who were randomly assigned (1:1) to receive ChAdOx1 nCoV-19 or a meningococcal conjugate control (MenACWY) vaccine, provided upper airway swabs on a weekly basis and also if they developed symptoms of COVID-19 disease (a cough, a fever of 37·8°C or higher, shortness of breath, anosmia, or ageusia). Swabs were tested by nucleic acid amplification test (NAAT) for SARS-CoV-2 and positive samples were sequenced through the COVID-19 Genomics UK consortium. Neutralising antibody responses were measured using a live-virus microneutralisation assay against the B.1.1.7 lineage and a canonical non-B.1.1.7 lineage (Victoria). The efficacy analysis included symptomatic COVID-19 in seronegative participants with a NAAT positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to vaccine received. Vaccine efficacy was calculated as 1 - relative risk (ChAdOx1 nCoV-19 vs MenACWY groups) derived from a robust Poisson regression model. This study is continuing and is registered with ClinicalTrials.gov, NCT04400838, and ISRCTN, 15281137.

FINDINGS

Participants in efficacy cohorts were recruited between May 31 and Nov 13, 2020, and received booster doses between Aug 3 and Dec 30, 2020. Of 8534 participants in the primary efficacy cohort, 6636 (78%) were aged 18-55 years and 5065 (59%) were female. Between Oct 1, 2020, and Jan 14, 2021, 520 participants developed SARS-CoV-2 infection. 1466 NAAT positive nose and throat swabs were collected from these participants during the trial. Of these, 401 swabs from 311 participants were successfully sequenced. Laboratory virus neutralisation activity by vaccine-induced antibodies was lower against the B.1.1.7 variant than against the Victoria lineage (geometric mean ratio 8·9, 95% CI 7·2-11·0). Clinical vaccine efficacy against symptomatic NAAT positive infection was 70·4% (95% CI 43·6-84·5) for B.1.1.7 and 81·5% (67·9-89·4) for non-B.1.1.7 lineages.

INTERPRETATION

ChAdOx1 nCoV-19 showed reduced neutralisation activity against the B.1.1.7 variant compared with a non-B.1.1.7 variant in vitro, but the vaccine showed efficacy against the B.1.1.7 variant of SARS-CoV-2.

FUNDING

UK Research and Innovation, National Institute for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midlands NIHR Clinical Research Network, and AstraZeneca.

Single-dose administration and the influence of the timing of the booster dose on immunogenicity and efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine: a pooled analysis of four randomised trials

BACKGROUND

The ChAdOx1 nCoV-19 (AZD1222) vaccine has been approved for emergency use by the UK regulatory authority, Medicines and Healthcare products Regulatory Agency, with a regimen of two standard doses given with an interval of 4-12 weeks. The planned roll-out in the UK will involve vaccinating people in high-risk categories with their first dose immediately, and delivering the second dose 12 weeks later. Here, we provide both a further prespecified pooled analysis of trials of ChAdOx1 nCoV-19 and exploratory analyses of the impact on immunogenicity and efficacy of extending the interval between priming and booster doses. In addition, we show the immunogenicity and protection afforded by the first dose, before a booster dose has been offered.

METHODS

We present data from three single-blind randomised controlled trials-one phase 1/2 study in the UK (COV001), one phase 2/3 study in the UK (COV002), and a phase 3 study in Brazil (COV003)-and one double-blind phase 1/2 study in South Africa (COV005). As previously described, individuals 18 years and older were randomly assigned 1:1 to receive two standard doses of ChAdOx1 nCoV-19 (5 × 10¹⁰ viral particles) or a control vaccine or saline placebo. In the UK trial, a subset of participants received a lower dose (2·2 × 10¹⁰ viral particles) of the ChAdOx1 nCoV-19 for the first dose. The primary outcome was virologically confirmed symptomatic COVID-19 disease, defined as a nucleic acid amplification test (NAAT)-positive swab combined with at least one qualifying symptom (fever ≥37·8°C, cough, shortness of breath, or anosmia or ageusia) more than 14 days after the second dose. Secondary efficacy analyses included cases occuring at least 22 days after the first dose. Antibody responses measured by immunoassay and by pseudovirus neutralisation were exploratory outcomes. All cases of COVID-19 with a NAAT-positive swab were adjudicated for inclusion in the analysis by a masked independent endpoint review committee. The primary analysis included all participants who were SARS-CoV-2 N protein seronegative at baseline, had had at least 14 days of follow-up after the second dose, and had no evidence of previous SARS-CoV-2 infection from NAAT swabs. Safety was assessed in all participants who received at least one dose. The four trials are registered at ISRCTN89951424 (COV003) and ClinicalTrials.gov, NCT04324606 (COV001), NCT04400838 (COV002), and NCT04444674 (COV005).

FINDINGS

Between April 23 and Dec 6, 2020, 24 422 participants were recruited and vaccinated across the four studies, of whom 17 178 were included in the primary analysis (8597 receiving ChAdOx1 nCoV-19 and 8581 receiving control vaccine). The data cutoff for these analyses was Dec 7, 2020. 332 NAAT-positive infections met the primary endpoint of symptomatic infection more than 14 days after the second dose. Overall vaccine efficacy more than 14 days after the second dose was 66·7% (95% CI 57·4-74·0), with 84 (1·0%) cases in the 8597 participants in the ChAdOx1 nCoV-19 group and 248 (2·9%) in the 8581 participants in the control group. There were no hospital admissions for COVID-19 in the ChAdOx1 nCoV-19 group after the initial 21-day exclusion period, and 15 in the control group. 108 (0·9%) of 12 282 participants in the ChAdOx1 nCoV-19 group and 127 (1·1%) of 11 962 participants in the control group had serious adverse events. There were seven deaths considered unrelated to vaccination (two in the ChAdOx1 nCov-19 group and five in the control group), including one COVID-19-related death in one participant in the control group. Exploratory analyses showed that vaccine efficacy after a single standard dose of vaccine from day 22 to day 90 after vaccination was 76·0% (59·3-85·9). Our modelling analysis indicated that protection did not wane during this initial 3-month period. Similarly, antibody levels were maintained during this period with minimal waning by day 90 (geometric mean ratio [GMR] 0·66 [95% CI 0·59-0·74]). In the participants who received two standard doses, after the second dose, efficacy was higher in those with a longer prime-boost interval (vaccine efficacy 81·3% [95% CI 60·3-91·2] at ≥12 weeks) than in those with a short interval (vaccine efficacy 55·1% [33·0-69·9] at <6 weeks). These observations are supported by immunogenicity data that showed binding antibody responses more than two-fold higher after an interval of 12 or more weeks compared with an interval of less than 6 weeks in those who were aged 18-55 years (GMR 2·32 [2·01-2·68]).

INTERPRETATION

The results of this primary analysis of two doses of ChAdOx1 nCoV-19 were consistent with those seen in the interim analysis of the trials and confirm that the vaccine is efficacious, with results varying by dose interval in exploratory analyses. A 3-month dose interval might have advantages over a programme with a short dose interval for roll-out of a pandemic vaccine to protect the largest number of individuals in the population as early as possible when supplies are scarce, while also improving protection after receiving a second dose.

FUNDING

UK Research and Innovation, National Institutes of Health Research (NIHR), The Coalition for Epidemic Preparedness Innovations, the Bill & Melinda Gates Foundation, the Lemann Foundation, Rede D'Or, the Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.

Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK

BACKGROUND

A safe and efficacious vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), if deployed with high coverage, could contribute to the control of the COVID-19 pandemic. We evaluated the safety and efficacy of the ChAdOx1 nCoV-19 vaccine in a pooled interim analysis of four trials.

METHODS

This analysis includes data from four ongoing blinded, randomised, controlled trials done across the UK, Brazil, and South Africa. Participants aged 18 years and older were randomly assigned (1:1) to ChAdOx1 nCoV-19 vaccine or control (meningococcal group A, C, W, and Y conjugate vaccine or saline). Participants in the ChAdOx1 nCoV-19 group received two doses containing 5 × 1010 viral particles (standard dose; SD/SD cohort); a subset in the UK trial received a half dose as their first dose (low dose) and a standard dose as their second dose (LD/SD cohort). The primary efficacy analysis included symptomatic COVID-19 in seronegative participants with a nucleic acid amplification test-positive swab more than 14 days after a second dose of vaccine. Participants were analysed according to treatment received, with data cutoff on Nov 4, 2020. Vaccine efficacy was calculated as 1 - relative risk derived from a robust Poisson regression model adjusted for age. Studies are registered at ISRCTN89951424 and ClinicalTrials.gov, NCT04324606, NCT04400838, and NCT04444674.

FINDINGS

Between April 23 and Nov 4, 2020, 23 848 participants were enrolled and 11 636 participants (7548 in the UK, 4088 in Brazil) were included in the interim primary efficacy analysis. In participants who received two standard doses, vaccine efficacy was 62·1% (95% CI 41·0-75·7; 27 [0·6%] of 4440 in the ChAdOx1 nCoV-19 group vs71 [1·6%] of 4455 in the control group) and in participants who received a low dose followed by a standard dose, efficacy was 90·0% (67·4-97·0; three [0·2%] of 1367 vs 30 [2·2%] of 1374; pinteraction=0·010). Overall vaccine efficacy across both groups was 70·4% (95·8% CI 54·8-80·6; 30 [0·5%] of 5807 vs 101 [1·7%] of 5829). From 21 days after the first dose, there were ten cases hospitalised for COVID-19, all in the control arm; two were classified as severe COVID-19, including one death. There were 74 341 person-months of safety follow-up (median 3·4 months, IQR 1·3-4·8): 175 severe adverse events occurred in 168 participants, 84 events in the ChAdOx1 nCoV-19 group and 91 in the control group. Three events were classified as possibly related to a vaccine: one in the ChAdOx1 nCoV-19 group, one in the control group, and one in a participant who remains masked to group allocation.

INTERPRETATION

ChAdOx1 nCoV-19 has an acceptable safety profile and has been found to be efficacious against symptomatic COVID-19 in this interim analysis of ongoing clinical trials.

FUNDING

UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, Bill & Melinda Gates Foundation, Lemann Foundation, Rede D'Or, Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.

Estimating the COVID-19 epidemic trajectory and hospital capacity requirements in South West England: a mathematical modelling framework

OBJECTIVES

To develop a regional model of COVID-19 dynamics for use in estimating the number of infections, deaths and required acute and intensive care (IC) beds using the South West England (SW) as an example case.

DESIGN

Open-source age-structured variant of a susceptible-exposed-infectious-recovered compartmental mathematical model. Latin hypercube sampling and maximum likelihood estimation were used to calibrate to cumulative cases and cumulative deaths.

SETTING

SW at a time considered early in the pandemic, where National Health Service authorities required evidence to guide localised planning and support decision-making.

PARTICIPANTS

Publicly available data on patients with COVID-19.

PRIMARY AND SECONDARY OUTCOME MEASURES

The expected numbers of infected cases, deaths due to COVID-19 infection, patient occupancy of acute and IC beds and the reproduction ('R') number over time.

RESULTS

SW model projections indicate that, as of 11 May 2020 (when 'lockdown' measures were eased), 5793 (95% credible interval (CrI) 2003 to 12 051) individuals were still infectious (0.10% of the total SW population, 95% CrI 0.04% to 0.22%), and a total of 189 048 (95% CrI 141 580 to 277 955) had been infected with the virus (either asymptomatically or symptomatically), but recovered, which is 3.4% (95% CrI 2.5% to 5.0%) of the SW population. The total number of patients in acute and IC beds in the SW on 11 May 2020 was predicted to be 701 (95% CrI 169 to 1543) and 110 (95% CrI 8 to 464), respectively. The R value in SW was predicted to be 2.6 (95% CrI 2.0 to 3.2) prior to any interventions, with social distancing reducing this to 2.3 (95% CrI 1.8 to 2.9) and lockdown/school closures further reducing the R value to 0.6 (95% CrI 0.5 to 0.7).

CONCLUSIONS

The developed model has proved a valuable asset for regional healthcare services. The model will be used further in the SW as the pandemic evolves, and-as open-source software-is portable to healthcare systems in other geographies.

Safety and immunogenicity of the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2: a preliminary report of a phase 1/2, single-blind, randomised controlled trial

BACKGROUND

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might be curtailed by vaccination. We assessed the safety, reactogenicity, and immunogenicity of a viral vectored coronavirus vaccine that expresses the spike protein of SARS-CoV-2.

METHODS

We did a phase 1/2, single-blind, randomised controlled trial in five trial sites in the UK of a chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19) expressing the SARS-CoV-2 spike protein compared with a meningococcal conjugate vaccine (MenACWY) as control. Healthy adults aged 18-55 years with no history of laboratory confirmed SARS-CoV-2 infection or of COVID-19-like symptoms were randomly assigned (1:1) to receive ChAdOx1 nCoV-19 at a dose of 5 × 10¹⁰ viral particles or MenACWY as a single intramuscular injection. A protocol amendment in two of the five sites allowed prophylactic paracetamol to be administered before vaccination. Ten participants assigned to a non-randomised, unblinded ChAdOx1 nCoV-19 prime-boost group received a two-dose schedule, with the booster vaccine administered 28 days after the first dose. Humoral responses at baseline and following vaccination were assessed using a standardised total IgG ELISA against trimeric SARS-CoV-2 spike protein, a muliplexed immunoassay, three live SARS-CoV-2 neutralisation assays (a 50% plaque reduction neutralisation assay [PRNT₅₀]; a microneutralisation assay [MNA₅₀, MNA₈₀, and MNA₉₀]; and Marburg VN), and a pseudovirus neutralisation assay. Cellular responses were assessed using an ex-vivo interferon-γ enzyme-linked immunospot assay. The co-primary outcomes are to assess efficacy, as measured by cases of symptomatic virologically confirmed COVID-19, and safety, as measured by the occurrence of serious adverse events. Analyses were done by group allocation in participants who received the vaccine. Safety was assessed over 28 days after vaccination. Here, we report the preliminary findings on safety, reactogenicity, and cellular and humoral immune responses. The study is ongoing, and was registered at ISRCTN, 15281137, and ClinicalTrials.gov, NCT04324606.

FINDINGS

Between April 23 and May 21, 2020, 1077 participants were enrolled and assigned to receive either ChAdOx1 nCoV-19 (n=543) or MenACWY (n=534), ten of whom were enrolled in the non-randomised ChAdOx1 nCoV-19 prime-boost group. Local and systemic reactions were more common in the ChAdOx1 nCoV-19 group and many were reduced by use of prophylactic paracetamol, including pain, feeling feverish, chills, muscle ache, headache, and malaise (all p<0·05). There were no serious adverse events related to ChAdOx1 nCoV-19. In the ChAdOx1 nCoV-19 group, spike-specific T-cell responses peaked on day 14 (median 856 spot-forming cells per million peripheral blood mononuclear cells, IQR 493-1802; n=43). Anti-spike IgG responses rose by day 28 (median 157 ELISA units [EU], 96-317; n=127), and were boosted following a second dose (639 EU, 360-792; n=10). Neutralising antibody responses against SARS-CoV-2 were detected in 32 (91%) of 35 participants after a single dose when measured in MNA₈₀ and in 35 (100%) participants when measured in PRNT₅₀. After a booster dose, all participants had neutralising activity (nine of nine in MNA₈₀ at day 42 and ten of ten in Marburg VN on day 56). Neutralising antibody responses correlated strongly with antibody levels measured by ELISA (R²=0·67 by Marburg VN; p<0·001).

INTERPRETATION

ChAdOx1 nCoV-19 showed an acceptable safety profile, and homologous boosting increased antibody responses. These results, together with the induction of both humoral and cellular immune responses, support large-scale evaluation of this candidate vaccine in an ongoing phase 3 programme.

FUNDING

UK Research and Innovation, Coalition for Epidemic Preparedness Innovations, National Institute for Health Research (NIHR), NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and the German Center for Infection Research (DZIF), Partner site Gießen-Marburg-Langen.

A cross-sectional observational study of pneumococcal carriage in children, their parents, and older adults following the introduction of the 7-valent pneumococcal conjugate vaccine

Using nasopharyngeal carriage as a marker of vaccine impact, pneumococcal colonization and its relation to invasive disease were examined in children, their parents, and older adults in the United Kingdom following introduction of 7-valent pneumococcal conjugate vaccine (PCV7) and prior to 13-valent pneumococcal conjugate vaccine (PCV13).A cross-sectional observational study was conducted, collecting nasopharyngeal swabs from children aged 25 to 55 months who had previously received 3 doses of PCV7, their parents, and adults aged ≥65 years. Pneumococcal serotyping was conducted according to World Health Organization guidelines with nontypeable isolates further analyzed by molecular serotyping. A national invasive disease surveillance program was conducted throughout the corresponding period.Pneumococcus was isolated from 47% of children, 9% of parents, and 2.2% of older adults. For these groups, the percentage of serotypes covered by PCV7 were 1.5%, 0.0%, and 15.4%, with a further 20.1%, 44.4%, and 7.7% coverage added by those in PCV13. In each group, the percentage of disease due to serotypes covered by PCV7 were 1.0%, 7.4% and 5.1% with a further 65.3%, 42.1%, and 61.4% attributed to those in PCV13.The prevalence of carriage is the highest in children, with direct vaccine impact exemplified by low carriage and disease prevalence of PCV7 serotypes in vaccinated children, whereas the indirect effects of herd protection are implied by similar observations in unvaccinated parents and older adults.

Avian influenza: recent epidemiology, travel-related risk, and management

H5N1 influenza continues to smolder in Southeast Asia over the past 5 years, but the emergence of H7N9 in China in 2012 raised concerns for a new avian influenza threat. In contrast with H5N1 with over 650 confirmed cases over 11 years, H7N9 has infected over 450 persons within 2 years. The case fatality rate for H7N9 (35 %) is lower than for H5N1 (60 %) or H10N8 (67 %) but is comparable to that for the Middle East respiratory syndrome coronavirus (MERS CoV), another emerging zoonosis with travel-associated importations. Exposure to poultry and fomites are considered the likely sources of infection for H7N9, H5N1, and H10N8, with limited human-to-human transmission in close contacts. Most cases have occurred in local populations of affected countries, and travel-related risk can be mitigated by avoiding exposure. Vaccines, antivirals, and other therapeutics remain in development stage or of modest benefit for dangerous infections carrying high morbidity and mortality.

The effect of chronic cytomegalovirus infection on pneumococcal vaccine responses

BACKGROUND

Immune function declines with age and has been associated with reduced vaccine responsiveness. Chronic infection with cytomegalovirus (CMV) has been proposed as a contributor to poorer responses in older adults. A pneumococcal vaccine has been recommended in the United Kingdom for those aged >65 years since 2003 to prevent pneumococcal disease.

METHODS

We evaluated the effect of age and CMV status on pneumococcal vaccine responses in 348 individuals aged 50-70 years.

RESULTS

We found participant age to be associated with serotype-specific and functional antibody titers after pneumococcal vaccination, with a mean 6.2% (95% confidence interval, 2.9%-9.5%) reduction in postvaccination functional antibody titers per year. CMV status was not associated with serotype-specific immunoglobulin G concentrations or functional antibody titers after pneumococcal vaccination. However, CMV seropositivity was associated with higher levels of prevaccination functional antibody for 4 of 7 pneumococcal serotypes assessed.

CONCLUSIONS

These data imply that CMV infection is not directly responsible for the decline in pneumococcal vaccine responses seen with age but suggest that CMV-seropositive individuals differ in their natural exposure to pneumococci or have altered mucosal immune responses after colonization with this organism.

Clostridium septicum sepsis and its implications

An elderly gentleman, who had 12 years earlier been successfully treated for colon cancer, presented with fever, rigours, right upper quadrant abdominal pain and tenderness. A CT of the abdomen revealed a colonic mass distal to the hepatic flexure with multiple gas locules and a walled off perforation. He underwent a right hemicolectomy. Histology confirmed multifocal colonic adenocarcinoma. His admission blood cultures grew Clostridium septicum. A week postoperatively he developed intermittent fevers and abdominal pain. Repeat CT revealed an abdominal collection adjacent to the new anastomosis, but more importantly, a sharply shouldered aneurysmal dilation of the infra-renal abdominal aorta. These findings prompted immediate surgical drainage of the collection, repair of the anastomostic leak, resection of the infected aortic aneurysm and replacement with a tube graft. This case highlights the clinical significance of C septicum bacteraemia: its association with occult colonic malignancy and with mycotic aneurysm formation. Clostridia isolated from blood cultures should not be dismissed as contaminants but fully identified to ensure appropriate patient management.

Pneumococcal conjugate and plain polysaccharide vaccines have divergent effects on antigen-specific B cells

BACKGROUND

A 23-valent unconjugated pneumococcal polysaccharide vaccine (23vP), routinely administered at the age of 65, has limited effectiveness, and revaccination induces attenuated antibody responses. It is not known whether pneumococcal polysaccharide-protein conjugated vaccines (PCV), although highly effective in infants, offer any immunological advantages over 23vP in adults.

METHODS

We immunized adults with schedules combining both PCV and 23vP and investigated B-cell responses to establish whether PCV7 (a 7-valent PCV) induced T-dependent responses in adults, to assess the role of memory B cells in 23vP-induced antibody hyporesponsiveness, and to identify the B-cell subtypes involved.

RESULTS

A single dose of PCV7 induced significant increases in serotype-specific memory B-cell populations in peripheral blood indicating a T-dependent response. Conversely, immunization with 23vP resulted in a decrease in memory B-cell frequency. Furthermore, memory B-cell responses to subsequent immunization with PCV7, when given after 23vP, were attenuated. Notably, B1b cells, a subset important in protecting mice against pneumococci, were also depleted following immunization with 23vP in humans.

CONCLUSIONS

This study indicates that PCV7 may have an immunological advantage over 23vP in adults and that 23vP-induced depletion of memory and B1b-cell subsets may provide a basis for antibody hyporesponsiveness and the limited effectiveness of 23vP. Clinical Trials Registration. ISRCTN: 78768849.

Acute necrotizing sinusitis caused by Staphylococcus lugdunensis

Staphylococcus lugdunensis is most commonly associated with infections arising from the inguinal region, but here we report this organism as a cause of bacterial sinusitis, highlighting its potential niche as a commensal of the upper airways. The severity of necrosis demonstrates the potential for destructive pathology mimicking Staphylococcus aureus disease.

Humoral and cellular immune responses to split-virion H5N1 influenza vaccine in young and elderly adults

We evaluated the humoral and cellular immunogenicity of adjuvanted and non-adjuvanted H5N1 influenza vaccine in two groups of 300 adults: aged 18-60 and >60 years in a randomized, open-label, uncontrolled phase 2 trial. Participants received two injections (D0, D21) of 7.5 microg hemagglutinin without adjuvant or 30 microg with aluminum hydroxide adjuvant. Antibody responses and cytokine secretion were assessed before and after vaccination. Excluding the 6/300 non-elderly and 47/300 elderly participants with pre-existing antibodies, geometric mean titers (dil(-1)) on D42 were higher with 30 microg+Ad and were comparable between age groups. Participants with pre-existing antibodies responded strongly to the first vaccination (GMTs in the range 147-228 on D21). Vaccination increased both Th1 and Th2 T-cell responses. The predominantly Th1 profile observed before vaccination was unaffected by vaccination. H5N1 influenza vaccine is no less immunogenic in elderly adults than in younger adults and, due to a higher proportion non-naïve elderly, immunogenicity was higher in this latter group.

Hopes, fears, knowledge and misunderstandings: responses of HIV-positive mothers to early knowledge of the status of their baby

Little is known about how HIV-positive mothers experience and react to knowing the HIV status of their baby as diagnosed by the polymerase chain reaction (PCR) test at 4-6 weeks. This qualitative study drew on interviews with 20 mothers of HIV-negative and 18 mothers of HIV-positive babies after receiving their baby's PCR results. Thematic analysis combined exploration of themes that appeared significant to the participants and those relevant to health care. Amongst the themes identified were the following: The period before getting the results involved active mental preparation and was emotionally stressful. Most women accepted the results, but some had doubts about their reliability. Mothers of HIV-negative babies were relieved, but mothers of HIV-positive babies were generally very distressed and expressed a sense of responsibility and guilt. Both groups of mothers had similar hopes for the future of their babies, but the timelines of mothers of HIV-positive babies tended to be shorter. Most women experienced significant levels of stress, but were able to call on support networks and use various individual coping mechanisms to manage their stress. Most women were formula feeding their babies, but regretted not being able to breastfeed. Many women had not planned their current baby and most did not intend to have more children, but many of the latter had not taken active steps to prevent further pregnancy. The findings provide pointers to shortcomings in health worker communication and suggest that more effective communication should take account of normative community views and be more closely attuned to the changing needs and experiences of HIV-positive mothers.

Cutaneous Salmonella infection

Pustular dermatitis caused by Salmonella stanley developed on the arm of a veterinary surgeon after the delivery of a dead bovine calf. The vet did not develop any systemic symptoms and made a full recovery. This is the only report of cutaneous infection caused by this organism.

Overview of the pharmacogenetics of asthma treatment

Asthma affects approximately 300 million individuals worldwide. Medications comprise a substantial portion of asthma expenditures. Despite the availability of three primary therapeutic classes of medications, there are a significant number of nonresponders to therapy. Available data, as well as previous pharmacogenetic studies, suggest that genetics may contribute as much as 60-80% to the interindividual variability in treatment response. In this methodologic review, after providing a broad overview of the asthma pharmacogenetics literature to date, we describe the application of a novel family-based screening algorithm to the analysis of pharmacogenetic data and highlight our approach to identifying and verifying loci influencing asthma treatment response. This approach seeks to address issues related to multiple comparisons, statistical power, population stratification, and failure to replicate from which previous population-based or case-control pharmacogenetic association studies may suffer. Identification of such replicable loci is the next step towards the goal of 'individualized therapy' for asthma.

Association of CommonCRPGene Variants with CRP Levels and Cardiovascular Events

C-reactive protein (CRP) is a well-documented marker of atherosclerotic cardiovascular disease risk. We resequenced CRP to identify a comprehensive set of common SNP variants, then studied and replicated their association with baseline CRP level among apparently healthy subjects in the Women's Health Study (WHS; n = 717), Pravastatin Inflammation/CRP Evaluation trial (PRINCE; n = 1,110) and Physicians' Health Study (PHS; n = 509) cohorts. The minor alleles of four SNPs were consistently associated in all three cohorts with higher CRP, while the minor alleles of two SNPs were associated with lower CRP (p < 0.05 for each). Single marker and haplotype analysis in all three cohorts were consistent with functional roles for the 5'-flanking triallelic SNP -286C>T>A and the 3'-UTR SNP 1846G>A. None of the SNPs associated with higher CRP were associated with risk of incident myocardial infarction (MI) or ischemic stroke in a prospective, nested case-control study design from the PHS cohort (610 case-control pairs). One SNP, -717A>G, was unrelated to CRP levels but associated with decreased risk of MI (p = 0.001). Taken together, these data imply significant interactions between both genetic and environmental contributions to the increased CRP levels that predict a greater risk of future atherothrombotic events in epidemiological studies.

Polymorphisms in the interleukin 17F gene (IL17F) and asthma

Interleukin17F (IL17F) is a regulatory cytokine for T-cell-mediated immune responses. The gene coding for IL17F (IL17F) is located on chromosome 6p, a genomic region linked to asthma and asthma-related phenotypes in multiple genome scans. IL17F is expressed in lung tissue, in bronchoalveolar lavage fluid from asthmatic subjects, and in activated CD4+ cells. We were thus interested in testing for association between single-nucleotide polymorphisms (SNPs) and haplotypes in IL17F and asthma. To characterize polymorphisms in IL17F, we sequenced this gene in a group of African Americans and a group of European Americans. A total of 50 SNPs (30 not previously reported in a public database (dbSNP build 118)) and two insertions/deletions were detected in IL17F; five of these polymorphisms were genotyped in participants of the Nurses' Health Study. We then tested for association between SNPs and haplotypes in IL17F and physician-diagnosed asthma in subjects with (cases) and without (control subjects) physician-diagnosed asthma. None of the SNPs or haplotypes tested in IL17F were associated with asthma. The polymorphisms identified in this study may be used in future studies of association between IL17F and phenotypes related to immune responses.

The risk of metachronous neoplasia in patients with serrated adenoma

Serrated adenomas are the precursors of at least 5.8% of colorectal cancers; otherwise little is known of their clinical significance in comparison with conventional adenomas and hyperplastic polyps. We compared the risk of metachronous lesions in colorectal serrated adenomas, conventional adenomas, and hyperplastic polyps. A consecutive series of patients with colorectal polyps first diagnosed from January 1978 to December 1982 and follow-up specimens to the end of 2000 was reviewed, and 239 polyps fulfilling the selection criteria were chosen as index polyps. The type of polyp seen in follow-up correlated significantly with the type of the initial lesion. Serrated adenomas were estimated to grow faster than conventional adenomas, but the incidence of colorectal cancer did not differ significantly between serrated (2/38 [5%]) and conventional adenomas (2.2%). The results indicate that serrated adenomas are lesions with a significant risk of metachronous serrated adenomas and the development of cancer. We emphasize the need for the proper recognition and management of serrated adenomas.

The risk of metachronous neoplasia in patients with serrated adenoma

Serrated adenomas are the precursors of at least 5.8% of colorectal cancers; otherwise little is known of their clinical significance in comparison with conventional adenomas and hyperplastic polyps. We compared the risk of metachronous lesions in colorectal serrated adenomas, conventional adenomas, and hyperplastic polyps. A consecutive series of patients with colorectal polyps first diagnosed from January 1978 to December 1982 and follow-up specimens to the end of 2000 was reviewed, and 239 polyps fulfilling the selection criteria were chosen as index polyps. The type of polyp seen in follow-up correlated significantly with the type of the initial lesion. Serrated adenomas were estimated to grow faster than conventional adenomas, but the incidence of colorectal cancer did not differ significantly between serrated (2/38 [5%]) and conventional adenomas (2.2%). The results indicate that serrated adenomas are lesions with a significant risk of metachronous serrated adenomas and the development of cancer. We emphasize the need for the proper recognition and management of serrated adenomas.

White matter lesions on magnetic resonance imaging and their relationship with vascular risk factors in memory clinic attenders

BACKGROUND

The association between white matter lesions on magnetic resonance imaging (MRI) and the presence of vascular risk factors has been investigated in different populations, and results have varied widely. However, this relationship has not been adequately addressed in memory clinic attenders who have relatively early cognitive impairment.

OBJECTIVES

This study was undertaken to determine the relationship between the severity of white matter lesions and vascular risk factors in elderly subjects referred to a Memory Clinic, irrespective of their diagnoses. Patients attending the Memory Clinic had relatively early, mild cognitive impairment and differed, in this respect, from typical unselected community-based samples and from patients with established dementia. The study also investigated whether periventricular and deep white matter lesions differed in their relationship with vascular risk factors.

METHODS

All patients assessed in the Memory Clinic at Leicester General Hospital between April 1998 and October 2000 who had undergone an MRI scan were included in the study. They received a comprehensive clinical and cognitive assessment, a standard dementia laboratory screen and evaluation of vascular risk factors. MRI scans were reviewed by two independent raters and semi-quantitative ratings of the severity of white matter lesions were made using standardised protocols. The relationship between cerebral white matter lesions and vascular risk factor variables was examined by multiple linear regression.

RESULTS

One hundred and seventy-seven subjects were included in the study. The mean age was 69.8 and the mean MMSE score was 23.2. Of the risk factors investigated, only age and prior cerebrovascular disease were significantly associated with severe periventricular white matter lesions; age, hypertension and diabetes were significantly associated with severe deep white matter lesions.

CONCLUSIONS

Periventricular and deep white matter lesions are differentially influenced by vascular risk factors.

Toll-like receptor 6 gene (TLR6): single-nucleotide polymorphism frequencies and preliminary association with the diagnosis of asthma

Toll-like receptor 6 (TLR6) is one of a series of highly conserved innate immune receptors. We resequenced TLR6 in DNA samples from 24 African Americans, 23 European Americans, and 24 Hispanic Americans, identifying 53 SNPs, 22 with an allele frequency >5%. Significant differences in SNP frequencies among the three populations were noted. In all, 11 SNPs caused amino-acid changes, including one with a frequency >5% in all three populations. Utilizing this SNP (Ser249Pro), we performed exploratory nested case-control disease-association studies, including one involving 56 African Americans with asthma and 93 African American controls. The minor allele of this SNP was associated with decreased risk for asthma (odds ratio 0.38, 95% CI 0.16-0.87, P=0.01), an effect consistent with the known biology of the toll-like receptors. Although replication of this finding in other, larger samples is needed, variation in TLR6 may have relevance to the pathogenesis of immunologically mediated diseases.

National Bioterrorism Syndromic Surveillance Demonstration Program

The National Bioterrorism Syndromic Surveillance Demonstration Program identifies new cases of illness from electronic ambulatory patient records. Its goals are to use data from health plans and practice groups to detect localized outbreaks and to facilitate rapid public health follow-up. Data are extracted nightly on patient encounters occurring during the previous 24 hours. Visits or calls with diagnostic codes corresponding to syndromes of interest are counted; repeat encounters are excluded. Daily counts of syndromes by zip code are sent to a central data repository, where they are statistically analyzed for unusual clustering by using a model-adjusted SaTScan approach. The results and raw data are displayed on a restricted website. Patient-level information stays at the originating health-care organization unless required by public health authorities. If a cluster surpasses a threshold of statistical aberration chosen by the corresponding public health department, an electronic alert can be sent to that department. The health department might then call a clinical responder, who has electronic access to records of cases contributing to clusters. The system is flexible, allowing for changes in participating organizations, syndrome definitions, and alert thresholds. It is transparent to clinicians and has been accepted by the health-care organizations that provide the data. The system's data are usable by local and national health agencies. Its software is compatible with commonly used systems and software and is mostly open-source. Ongoing activities include evaluating the system's ability to detect naturally occurring outbreaks and simulated terrorism events, automating and testing alerts and response capability, and evaluating alternative data sources.

Lesson of the week: perils of pessaries

Vaginal pessaries are widely considered to be a safe alternative to surgery in older women. We report a case of near fatal septicaemia in a 75-year-old woman associated with a shelf pessary, the presence of which was identified during an exploratory laparotomy. This case highlights the importance of the gynaecological history and examination when assessing older women with septicaemia of unknown source.

Non-bronchoscopic bronchoalveolar lavage in the microbiological diagnosis of pneumonia in mechanically ventilated patients

A prospective study comparing standardized non-bronchoscopic bronchoalveolar lavage (sNB-BAL) and non-specific endotracheal aspirate (NsETA) in the microbiological diagnosis of pneumonia in mechanically ventilated patients is described. One hundred episodes in 82 mechanically ventilated patients with or without radiological and clinical diagnostic criteria of pneumonia were studied. NsETA and sNB-BAL was performed on the day of study. Fifty-one patients had pneumonia (21 ventilator-associated, 12 hospital-acquired, 18 community-acquired) and 49 had no pneumonia as defined by widely accepted clinico-radiological criteria. The sNB-BAL was found to be significantly more specific (0. 73) compared to NsETA (0.35) for the microbiological diagnosis of pneumonia. Colonization rates with NsETA were significantly higher compared to sNB-BAL (P value <0.0001). No patient had complications attributable to the sNB-BAL procedure. We conlude that sNB-BAL is a safe, effective, sensitive, specific and inexpensive procedure for the serial evaluation of pneumonia in mechanically ventilated patients.

Umbilical cord blood lactate in normal infants: comparison between two methods of measurement

OBJECTIVES

Firstly, to determine the accuracy of the Radiometer ABL 625 lactate electrode (Radiometer Medical Pty Ltd, Nunawading, Victoria, Australia) by comparing the lactate values obtained by this method to those obtained with the Hitachi 917 lactate analyser (Boehringer Mannheim Corporation, Charlottetown, Prince Edward Island, Canada). Secondly, to determine the effect of delay in measurement on blood lactate levels.

METHODOLOGY

Umbilical venous (UCV) blood samples were obtained from healthy term infants delivered vaginally. Lactate levels were measured with the Radiometer ABL 625 lactate electrode in the Neonatal Intensive Care Unit, Westmead Hospital and with the Hitachi 917 lactate analyser in 49 paired samples. In addition 26 UCV blood samples were placed in ice slurry and a further 26 samples at room temperature and blood lactate was measured at 5-min intervals for 30 min to determine the change of lactate levels with time.

RESULTS

The lactate levels obtained from the Radiometer ABL 625 lactate electrode were consistently lower than the levels obtained from the Hitachi 917 lactate analyser (mean difference - 0.24), but the correlation was high (r = 0.97). The blood lactate levels increased at the rate of 0.012 mmol/L per min if the blood was left at room temperature. The lactate levels remained stable for 20 min if the blood was placed in ice slurry.

CONCLUSION

The Radiometer ABL 625 lactate electrode was easy to use and there was high correlation with the values obtained by the standard laboratory method. The blood specimen must be place in an ice slurry if a delay in analysis is anticipated.

Prevalence and prognostic significance of malnutrition in chronic renal insufficiency

OBJECTIVE

Malnutrition is present in a significant proportion of patients commencing dialysis. However, the prevalence and prognostic significance of malnutrition within the chronic renal insufficiency (CRI) population before the initiation of dialysis is poorly characterized. The aim of this study was to determine the prevalence and prognostic significance of malnutrition in an unselected group of patients with CRI.

DESIGN

Cohort analytic study.

SETTING

Ambulatory care practice of a university teaching hospital.

PATIENTS

Fifty patients with CRI (serum creatinine concentration > or = 1.7 mg/dL) were enrolled. Patients with a recent acute illness, nephrotic syndrome, intercurrent steroid therapy, gastrointestinal disease, or other severe organ failure that may have independently influenced nutritional status were excluded.

INTERVENTION

At baseline, patients had a nutritional assessment consisting of subjective global assessment (SGA), measurement of body mass index (BMI), midarm circumference (MAC), serum albumin concentration, total lymphocyte count, and single frequency bioelectrical impedance analysis. Patients received standard medical care and were followed prospectively at quarterly intervals for 12 months.

RESULTS

At baseline assessment, 28% of patients had evidence of malnutrition by SGA criteria. The malnourished group of patients had a significantly lower creatinine clearance (18.9 +/- 9.8 v 36.5 +/- 14.0 mL/min/1.73 m(2), mean +/- SD, P <.001), glomerular filtration rate (20.7 +/- 10.9 v 28.5 +/- 12.5 mL/min/1.73 m(2), P =.04), BMI (22.7 +/- 2.9 v 29.0 +/- 5.0 kg/m(2)), and MAC (24.3 +/- 4.9 v 30.7 +/- 4.8 cm, P <.001), but there were no differences in serum albumin concentration or total lymphocyte count between the groups. At the 12-month follow-up, there was significantly increased mortality (21% v 3%, P =.04), composite endpoint of death or dialysis (50% v 11%, P =.02), and likelihood of acute hospitalization (78% v 23%, P =.001) in the malnourished group. A significant association was observed between baseline nutritional status and subsequent admission to hospital and baseline glomerular filtration rate and progression to end-stage renal failure.

CONCLUSION

These data suggest that SGA provides a useful means of assessing nutritional status and is helpful in identifying patients with increased risk of morbidity and mortality in the setting of CRI.

Cost of dental services provided in private general practice for an insured population in New South Wales, Australia

OBJECTIVE

To determine cost of dental services provided to a cohort of insured population 18 years and over, who used private general dental practice in New South Wales, Australia.

BASIC RESEARCH DESIGN

This cohort study used the person-years method and Weibull regression for analysis. Setting Data were derived from claims records submitted for rebates by members of a health insurance fund for services they received in private general dental practice during 1 January 1992-31 December 1995.

PARTICIPANTS

75,501 members from New South Wales.

MAIN OUTCOME MEASURES

To determine, by age groups, the cost per item of dental service, cost of services received at a visit and cost of services received per year.

RESULTS

The median cost per item of dental service received for all ages was A$36.7; with cost increasing with age until 55-64 year age group where an apparent plateau occurred. The median cost of services received at a visit for all ages was Australian dollars 93.5. Cost of services received at a visit increased with age, reaching a plateau in the middle aged groups. The median cost of providing services for all age groups per year was Australian dollar 183.6. The cost of services per year when compared with the youngest age group (18-24 years) increased by about 20% for each successive age group up to the 45-54 year age group. From 55 years onwards the cost levelled off at approximately 70% more than the youngest age group.

CONCLUSION

The cost of providing dental services increased with age to reach a plateau in the middle age groups.

Australian dentists' views on toothbrush wear and renewal

The purpose of this study was to survey the views of Australian dentists on toothbrush wear, toothbrush renewal periods and recommendations to patients and to investigate the relationship between dentists' views on patients' toothbrush renewal intervals and dentists' own renewal habits. Questionnaires were mailed to 5,596 Australian general dental practitioners and replies received from 3,406 (61 per cent response rate). The majority of respondents (85.7 per cent) felt patients should renew their toothbrushes more often. However, only 45.3 per cent usually made a recommendation to their patients as to when they should renew their toothbrush and only 41.7 per cent thought patients actually followed such recommendations. Most respondents (56.6 per cent) thought the average adult patient should renew a toothbrush every two-three months. A renewal period of one month or earlier was recommended by 23.8 per cent of dentists; four-five months by 8 per cent; and six months or longer by 11.5 per cent. A highly significant correlation was found between the renewal periods recommended for patients and the intervals selected by the dentists for their personal brushes (p < 0.001; chi-square test). Bending and splaying of bristles was the sign identified by the majority of dentists (70 per cent) as indicating the need for a new brush. The findings suggest dentists' recommendations concerning toothbrush renewal intervals may be based on their own toothbrush renewal habits. It is also concluded that dentists think patients comply poorly with their recommendations on toothbrush renewal.

Prevalence of Huntington disease in New South Wales in 1996

OBJECTIVE

To estimate the prevalence of Huntington disease (HD) in New South Wales on Australian Census Day (6 August) 1996.

DESIGN

Survey of records of the Huntington Disease Service and major hospitals, and of neurologists, psychiatrists, clinical geneticists and genetic counsellors.

SUBJECTS AND SETTING

All patients in NSW who, on Census Day 1996, either had a definite diagnosis of HD (motor signs of chorea or ataxia and family history of HD or positive DNA test result) or would have had signs and later received a definite diagnosis (assessed 1 April 1997 to 1 July 1999).

MAIN OUTCOME MEASURES

Prevalence (HD patients per 100,000 population); patient characteristics; year and basis of diagnosis.

RESULTS

380 patients with definite HD were identified, giving a prevalence of HD in NSW in 1996 of 6.29 per 100,000 population (95% CI, 5.68-6.96). A third of HD patients were aged 60 years or older. Diagnosis was confirmed by DNA testing for 171 patients (45%), including 30 (8%) with no recorded family history. Average numbers of new diagnoses per year were 11.8 (1984-1988), 21.8 (1989-1993) and 28.6 (1994-1998). Estimated number of people with a 50% risk of inheriting the HD mutation was 25.2 per 100,000 population. Estimated incidence of HD in 1996 was 0.65 per 100,000 population.

CONCLUSIONS

Prevalence of HD in NSW is similar to estimated prevalence in other Australian and Western populations. Increasing numbers of cases are being diagnosed, and the 18 chronic care beds currently designated for HD patients in NSW are unlikely to be sufficient.

Change in body mass index in Australian primary school children, 1985-1997

BACKGROUND

Childhood obesity is an important, potentially modifiable risk factor for a range of concurrent and later morbidities. Despite concerns about recent increases in children's body mass index (BMI), supporting data in Australia (as elsewhere) are scant.

OBJECTIVE

To seek anthropometric evidence of a recent secular increase in BMI in primary school children in Victoria, Australia.

DESIGN

Data from two cross-sectional population-based surveys of primary school children (the Victorian subsample of the 1985 Australian Health and Fitness Survey and the 1997 Health of Young Victorians Study) were compared. Similar stratified random sampling and standardized measurement methods were employed in the two studies. Subjects were all children aged 7-12 y with complete height and weight data. Body mass index (BMI (weight/height2)) was used as the index of relative adiposity. Non-parametric and parametric methods were used to examine the pattern and magnitude of change in BMI over the 12 y interval.

RESULTS

Data for 1421 children (50% male, 68% response) from the 1985 survey and 2277 children (51% male, 75% response) from the 1997 survey were analysed. At all ages, mean height and median weight were greater in 1997 than 1985 for both boys and girls. Median BMI was significantly higher in the 1997 sample for all but 12 y-old girls and for boys aged 7, 8 and 10 y (Mann-Whitney U test). The magnitude of the overall increase in BMI was estimated using analysis of covariance for log-transformed BMI adjusted for exact age, which indicated an increase of 1.03 kg/m2 for boys and 1.04 kg/m2 for girls (both P<0. 001). Plots of BMI against BMI percentile clearly showed a pattern of higher BMI at any given percentile, especially at the upper percentiles, for all ages and both genders.

CONCLUSIONS

Primary school children in Victoria have become more obese over the last decade. Increases in BMI are most marked at the heavier end of the distribution. Lesser increases in median and mean BMI (confirmed by both parametric and non-parametric statistical models) may also have major public health implications.

Long-term mortality trends in patients with traumatic brain injury

Comparison of long-term mortality rates between patients with traumatic brain injury (TBI) and the general population has not been adequately investigated. This project aimed to obtain information on the long-term mortality rate of patients with TBI. Using a rehabilitation database of a major teaching hospital, the search identified 476 patients, of whom 27 were deceased. This mortality rate (5.7%) was compared with the expected mortality rate for an equivalent population without TBI (1.5%) using Australian Life Table data. It was found that patients with TBI had a significantly higher mortality rate than the general population (chi2 = 12.2, p < 0.001). Possible reasons for this finding are discussed.