Asymptomatic Contact Research Articles

Prevalence of infection among asymptomatic and paucisymptomatic contact persons exposed to Ebola virus in Guinea: a retrospective, cross-sectional observational study

The prevalence of Ebola virus infection among people who have been in contact with patients with Ebola virus disease remains unclear, but is essential to understand the dynamics of transmission. This study aimed to identify risk factors for seropositivity and to estimate the prevalence of Ebola virus infection in unvaccinated contact persons. In this retrospective, cross-sectional observational study, we recruited individuals between May 12, 2016, and Sept 8, 2017, who had been in physical contact with a patient with Ebola virus disease, from four medical centres in Guinea (Conakry, Macenta, N'zérékoré, and Forécariah). Contact persons had to be 7 years or older and not diagnosed with Ebola virus disease. Participants were selected through the Postebogui survivors' cohort. We collected self-reported information on exposure and occurrence of symptoms after exposure using a questionnaire, and tested antibody response against glycoprotein, nucleoprotein, and 40-kDa viral protein of Zaire Ebola virus by taking a blood sample. The prevalence of Ebola virus infection was estimated with a latent class model. 1721 contact persons were interviewed and given blood tests, 331 of whom reported a history of vaccination so were excluded, resulting in a study population of 1390. Symptoms were reported by 216 (16%) contact persons. The median age of participants was 26 years (range 7-88) and 682 (49%) were male. Seropositivity was identified in 18 (8·33%, 95% CI 5·01-12·80) of 216 paucisymptomatic contact persons and 39 (3·32%, 5·01-12·80) of 1174 (2-4) asymptomatic individuals (p=0·0021). Seropositivity increased with participation in burial rituals (adjusted odds ratio [aOR] 2·30, 95% CI 1·21-4·17; p=0·0079) and exposure to blood or vomit (aOR 2·15, 1·23-3·91; p=0·0090). Frequency of Ebola virus infection varied from 3·06% (95% CI 1·84-5·05) in asymptomatic contact persons who did not participate in burial rituals to 5·98% (2·81-8·18) in those who did, and from 7·17% (3·94-9·09) in paucisymptomatic contact persons who did not participate in burial rituals to 17·16% (12·42-22·31) among those who did. This study provides a new assessment of the prevalence of Ebola virus infection among contact persons according to exposure, provides evidence for the occurrence of paucisymptomatic cases, and reinforces the importance of closely monitoring at-risk contact persons. Institut National de la Santé et de la Recherche Médicale, Reacting, the French Ebola Task Force, Institut de Recherche pour le Développement, and Montpellier University Of Excellence-University of Montpellier.

Longitudinal study on enterovirus A71 and coxsackievirus A16 genotype/subgenotype replacements in hand, foot and mouth disease patients in Thailand, 2000–2017

BackgroundEnterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are the major causative agents of hand, foot and mouth disease (HFMD) worldwide, particularly in the Asia-Pacific region. Several strains have emerged, circulated, and faded out over time in recent decades. This study investigated the EV-A71 and CV-A16 circulating strains and replacement of genotypes/subgenotypes in Thailand during the years 2000–2017. MethodsThe complete VP1 regions of 92 enteroviruses obtained from 90 HFMD patients, one asymptomatic adult contact case, and one encephalitic case were sequenced and investigated for serotypes, genotypes, and subgenotypes using a phylogenetic analysis. ResultsThe 92 enterovirus isolates were identified as 67 (72.8%) EV-A71 strains comprising subgenotypes B4, B5, C1, C2, C4a, C4b and C5, and 25 (27.2%) CV-A16 strains comprising subgenotypes B1a and B1b. Genotypic/subgenotypic replacements were evidenced during the study period. EV-A71 B5 and C4a have been the major circulating strains in Thailand for more than a decade, and CV-A16 B1a has been circulating for almost two decades. ConclusionsThis study provides chronological data on the molecular epidemiology of EV-A71 and CV-A16 subgenotypes in Thailand. Subgenotypic replacement frequently occurred with EV-A71, but not CV-A16. Monitoring for viral genetic and subgenotypic changes is important for molecular diagnosis, vaccine selection, and vaccine development.

Complete genome analysis demonstrates multiple introductions of enterovirus 71 and coxsackievirus A16 recombinant strains into Thailand during the past decade

Hand, foot, and mouth disease (HFMD) caused by enteroviruses remains a public health threat, particularly in the Asia-Pacific region during the past two decades. Moreover, the introduction of multiple subgenotypes and the emergence of recombinant viruses is of epidemiological importance. Based on either the full genome or VP1 sequences, 32 enteroviruses (30 from HFMD patients, 1 from an encephalitic patient, and 1 from an asymptomatic contact case) isolated in Thailand between 2006 and 2014 were identified as 25 enterovirus 71 (EV71) isolates (comprising 20 B5, 1 C2, 2 C4a, and 2 C4b subgenotypes) and 7 coxsackievirus A16 (CA16) isolates (comprising 6 B1a and 1 B1b subgenotypes). The EV71 subgenotype C4b was introduced into Thailand for the first time in 2006 and was replaced by subgenotype C4a strains in 2009. Phylogenetic, similarity plot and bootscan analyses of the complete viral genomes identified 12 recombinant viruses among the 32 viral isolates. Only one EV71-B5 isolate out of 20 was a recombinant virus with one region of intratypic or intertypic recombination, while all four EV71-C4 isolates were recombinant viruses having undergone double recombination, and all seven CA16 isolates were recombinant viruses. The recombination breakpoints of these recombinants are located solely within the P2 and P3 regions. Surveillance for circulating strains and subgenotype replacement are important with respect to molecular epidemiology and the selection of the upcoming EV71 vaccine. In addition, the clinical importance of recombinant viruses needs to be further explored.

The ability of the Contact Lens Dry Eye Questionnaire (CLDEQ)-8 to detect ocular surface alterations in contact lens wearers.

To study whether some ocular surface alterations could be associated with contact lens (CL) wearers suffering from CL discomfort (CLD) detected using the Contact Lens Dry Eye Questionnaire (CLDEQ)-8. Forty-one soft CL wearers further classified into symptomatic CL wearers (SCLW) and asymptomatic CL wearers (ACLW) by the CLDEQ-8, and 20 non CL wearers (NCLW) were included. Tear osmolarity, slit-lamp biomicroscopy findings, tear film break-up time, corneal and conjunctival staining, and Schirmer test were performed 24 h after CL removal. Data were compared among groups using the analysis of variance and the Student t-test or the Kruskal-Wallis H and the Mann-Whitney U tests, applying the Bonferroni correction. Correlations between the CLDEQ-8 and the clinical signs were performed using the Spearman correlation coefficient. Twenty-four SCLW, 17 ACLW and 20 NCLW were recruited. There were significant differences among groups for tear osmolarity (p < 0.001), limbal hyperaemia (p = 0.014), and tarsal hyperaemia (p = 0.031). Pairwise comparisons revealed that SCLW and ACLW had higher tear osmolarity (p < 0.003, both comparisons) and limbal hyperaemia (p = 0.027 and p = 0.048, respectively) than NCLW. Moreover, SCLW had higher tarsal hyperaemia (p = 0.030) than NCLW. No significant correlations were found (p > 0.05). The CLDEQ-8 was ineffective to detect clinical alterations between SCLW and ACLW; therefore, the use of questionnaires alone remains being the best approach to detect CLD. The role of the tarsal conjunctiva in the development of CLD should be analyzed in future studies.

Tear film inflammatory cytokine upregulation in contact lens discomfort

PurposeTo investigate the ocular inflammatory response, using clinical and immunological techniques, in people experiencing contact lens (CL) discomfort. MethodsThis study involved 38 adults who were full-time, silicone-hydrogel CL wearers. Participants were categorized into groups based upon a validated CL dry-eye questionnaire (CLDEQ-8) (n = 17 ‘asymptomatic’, CLDEQ-8 score <9; n = 21 ‘symptomatic’, CLDEQ-8 score ≥13). Examinations were performed at two visits (one with, and one without, CL wear), separated by one-week. Testing included: tear osmolarity, ocular redness, tear stability, ocular surface staining, meibography, tear production and tear collection. Tear osmolarity was taken from the inferior-lateral and superior-lateral menisci. The ‘Inferior-Superior Osmotic Difference’, I-SOD, was the absolute osmolarity difference between these menisci. Concentrations of seven cytokines (IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-gamma, TNF-alpha) were assayed from basal tears using multiplex cytometric bead array. ResultsAt baseline, there was no significant difference in key clinical signs between asymptomatic and symptomatic CL wearers (p > 0.05). The I-SOD was greater in symptomatic than asymptomatic CL wearers (23.1 ± 2.6 versus 11.3 ± 1.4 mOsmol/L, p = 0.001). People experiencing CL discomfort had higher tear IL-17A (122.6 ± 23.7 versus 44.0 ± 10.0 pg/mL, p = 0.02) and reduced tear stability (6.3 ± 1.1 versus 10.4 ± 1.6 s, p = 0.03) after several hours of CL wear. Tear IL-17A levels correlated with both the I-SOD (r = 0.43, p = 0.01) and CLDEQ-8 score (r = 0.40, p = 0.01). ConclusionsCL discomfort occurs in individuals having no clinical dry eye signs, and is associated with higher tear levels of the pro-inflammatory cytokine IL-17A. These findings support an association between the discomfort response and low-grade, ocular surface inflammation.

Are Contact Lens Discomfort or Soft Contact Lens Material Properties Associated with Alterations in the Corneal Sub-Basal Nerve Plexus?

ABSTRACTPurpose: To study whether contact lens (CL) discomfort and some properties of soft CL materials are associated with alterations in the nerve fibers morphology and density of dendritic cells of the corneal sub-basal nerve plexus.Materials and Methods: Forty soft CL wearers and 20 non-CL wearers were included. The Contact Lens Dry Eye Questionnaire-short form was administered to divide CL wearers based on their symptoms (20 symptomatic and 20 asymptomatic CL wearers were included). The CL material properties considered were the CL material type (16 hydrogel and 24 silicone hydrogel CL wearers were included), water content, oxygen transmissibility, and modulus of elasticity. Confocal microscopy was performed, and the number and density of corneal nerves, density of nerve branches, grade of nerve tortuosity, and density of dendritic cells were analyzed. The effects of CL discomfort and CL material properties on the confocal microscopy parameters were analyzed.Results: No significant differences were found among symptomatic and asymptomatic CL wearers and non-CL wearers in any of the confocal microscopy parameters evaluated. The density of dendritic cells was higher in the hydrogel CL wearers compared to the silicone hydrogel CL wearers and non-CL wearers (p = 0.002). The density of dendritic cells tended to be higher as the oxygen transmissibility decreased (β = −0.40, p = 0.07).Conclusions: CL discomfort appears not to be associated with alterations in the corneal sub-basal nerve plexus. Hydrogel CL wear might be involved in the recruitment of dendritic cells into the cornea, being a possible origin its lower oxygen permeability compared to silicone hydrogel materials. Future studies are required to confirm these results.

Trigeminal neuralgia: When does neurovascular contact turn into a conflict?

BackgroundThe most common cause for trigeminal neuralgia is contact of the trigeminal nerve with an offending vessel which is also observed routinely in many asymptomatic patients. Therefore, the aim of this study was to determine when an asymptomatic Neuro Vascular Contact (NVC) turned into a neurovascular conflict and made the patient symptomatic. MethodsAll patients who underwent Magnetic Resonance Imaging (MRI) brain with clinical diagnosis of trigeminal neuralgia formed the study group and all cases of sensorineural hearing loss formed the control group. ResultsOut of 51 cases of trigeminal neuralgia 27 were males and 24 were females. The neurovascular contact was seen in 41 (80.4%) cases and 17 (28.3%) controls. Change in caliber of trigeminal nerve was seen in 27 (52.9%) cases and only in 01 (1.66%) control. Arterial imprint on nerve was seen in 26 (50.9%) cases and 01 (1.66%) control. Distortion of the course of nerve was seen in 12 (23.5%) cases and 01 (1.66%) control. Superior cerebellar artery was commonest vessel seen in contact with nerve on affected side in 25 (61%) cases. ConclusionDemonstrating neurovascular contact alone is not enough for diagnosis of conflict as it is also present in some asymptomatic individuals, therefore it is important to identify thinning of nerve, arterial imprint or grooving and distortion in course of nerve, as these are more reliable signs of a conflict between the vessel and the nerve, and these cases are best treated surgically by Micro Vascular Decompression (MVD).

Differences in Tear Film Biochemistry of Symptomatic and Asymptomatic Lens Wearers.

The concentration of selected proteins and inflammatory mediators in tears of symptomatic and asymptomatic contact lens wearers were quantified. The level of leukotriene B4 was higher in the symptomatic group. This may suggest that inflammation can be the cause of discomfort sensation at the end of day. The present study aims to quantify the concentration of selected tear lipids and proteins in symptomatic and asymptomatic contact lens wearers. Unstimulated evening tears were collected using glass capillary tubes from 45 healthy, adapted contact lens wearers. Twenty-two had self-described symptoms of dryness and discomfort with contact lenses and 23 were asymptomatic. Tear proteins were assayed using selected reaction monitoring mass spectrometry. Enzyme immunoassay kits were used to measure prostaglandins, leukotriene B4, and cysteinyl leukotrienes. Ocular comfort was rated on a scale of 1 to 100 at the time of tear collection. The average evening comfort level was above 70 for the asymptomatic (83.96 ± 9.51, mean ± SE) and equal or below 70 for the symptomatic group (57.28 ± 12.38) (P < .001). LTB4 was significantly higher in symptomatic than asymptomatic contact lens wearers (0.32 ± 0.06 ng/μL vs. 0.17 ± 0.04 ng/μL, respectively; P = .03). Lysozyme was slightly but not significantly lower in symptomatic subjects (symptomatic 0.58 ± 0.10 mg/mL vs. asymptomatic 1.73 ± 0.46 mg/mL; P = .10). The levels of lactoferrin, lipocalin 1, proline-rich 4, prolactin-induced protein, prostaglandins, and cysteinyl leukotrienes were unchanged (P > .1) between symptomatic and asymptomatic subjects. The LTB4 concentration was significantly higher in symptomatic contact lens wearers compared to the asymptomatic group, and this may partly mediate the discomfort response during lens wear in the symptomatic lens wearers. No other differences were found in the level of tear factors of interest between the two groups.

Longitudinal changes in Langerhans cell density of the cornea and conjunctiva in contact lens‐induced dry eye

BackgroundThe aim was to determine longitudinal changes in Langerhans cell density (LCD) in the human cornea and conjunctiva during asymptomatic and symptomatic contact lens wear.MethodsTwenty‐five participants with contact lens‐induced dry eye (CLIDE) and 35 without CLIDE (NO‐CLIDE), diagnosed using a range of symptom questionnaires and objective tests (tear film break up, cotton thread tear test and corneal staining) were enrolled. The central cornea and nasal bulbar conjunctiva were examined using a Heidelberg laser scanning confocal microscope at baseline and following one, four and 24 weeks wear of daily disposable hydrogel contact lenses. Twenty‐three non‐contact lens‐wearing controls were also examined. Langerhans cells were counted manually from randomly selected images.ResultsIn the cornea, mean and standard error of the mean LCD was greater after one week of lens wear in CLIDE (55 ± 7 cells/mm2) versus NO‐CLIDE (43 ± 4 cells/mm2) (p = 0.041) and controls (27 ± 4 cells/mm2) (p < 0.001). LCD was also greater in NO‐CLIDE versus controls (p = 0.010). At week 4, LCD was greater in CLIDE (41 ± 6 cells/mm2) versus controls (27 ± 4 cells/mm2) (p = 0.004). There were no other significant differences between groups at weeks four or 24. In the conjunctiva, LCD was greater after one week of lens wear in CLIDE (17 ± 1 cells/mm2) (p = 0.003) and NO‐CLIDE (17 ± 3 cells/mm2) (p = 0.001) versus controls (7 ± 1 cells/mm2). There were no significant differences between groups at weeks four or 24.ConclusionsThe initial transient increase in corneal and conjunctival LCD in CLIDE (versus NO‐CLIDE) suggests an inflammatory component in the aetiology of this condition.

Temporal changes in contact lens comfort over a day of wear.

Contact lens discomfort continues to be reported as the primary reason for soft lens discontinuation, regardless of new modalities and materials. The purpose of this analysis of comfort related data from a series of clinical studies was to review whether there was a difference between symptomatic and asymptomatic habitual lens wearers' comfort responses over the course of the day. Data from five independent non-dispensing clinical studies were pooled and analysed. Participants in these studies were assigned to one of two groups depending on whether they were classified as symptomatic or asymptomatic contact lens wearers according to a modified Subjective Evaluation of Symptoms of Dryness (SESOD) questionnaire. Masked participants were randomised to wear either a hydrogel or a silicone hydrogel contact lens and their ocular comfort was rated using a visual analogue scale on insertion and 2-hourly during an 8-hour period of a single lens wearing day. Data from 103 participants were used, 58 in the symptomatic group and 45 in the asymptomatic group as determined by the SESOD questionnaire. There was no effect of lens material on comfort (p=0.43). However, there was a significant interaction between symptoms and time. The difference in mean comfort between the symptomatic and asymptomatic group was significant at each time point (p<0.05). However, comfort did not vary significantly over the day for the asymptomatic group (p=0.87), whereas, there was a significant decline in mean comfort ratings for the symptomatic group from 84.6±13.2 (S.D.) at insertion to 73.0±18.5 at 8hours (p<0.001). In our study, changes in contact lens comfort over a day were independent of lens material but not symptoms. Symptomatic lens wearers reported a progressive decrease in comfort, whereas asymptomatic wearers did not. Therefore, asymptomatic wearers should not be used when measuring contact lens comfort in clinical studies. The exclusion of asymptomatic lens wearers would likely increase the sensitivity of comfort ratings as a measure in contact lens research.

Hypersensitivity to Cold Stimuli in Symptomatic Contact Lens Wearers.

To examine the cooling thresholds and the estimated sensation magnitude at stimulus detection in controls and symptomatic and asymptomatic contact lens (CL) wearers, to determine whether detection thresholds depend on the presence of symptoms of dryness and discomfort. Forty-nine adapted CL wearers and 15 non-lens wearing controls had room temperature pneumatic thresholds measured using a custom Belmonte esthesiometer, during Visits 1 and 2 (Baseline CL), Visit 3 (2 weeks no CL wear), and Visit 4 (2 weeks after resuming CL wear). CL wearers were subdivided into symptomatic and asymptomatic groups based on comfortable wearing time (CWT) and CLDEQ-8 score (<8 hours CWT and ≥14 CLDEQ-8 stratified the symptom groups). Detection thresholds were estimated using an ascending method of limits and each threshold was the average of the three first-reported flow rates. The magnitude of intensity, coolness, irritation, and pain at detection of the stimulus were estimated using a 1-100 scale (1 very mild, 100 very strong). In all measurement conditions, the symptomatic CL wearers were the most sensitive, the asymptomatic CL wearers were the least sensitive, and the control group was between the two CL wearing groups (group factor p < 0.001, post hoc asymptomatic vs. symptomatic group, all p's < 0.015). Similar patterns were found for the estimated magnitude of intensity and irritation (group effect p = 0.027 and 0.006 for intensity and irritation, respectively) but not for cooling (p > 0.05) at detection threshold. Symptomatic CL wearers have higher cold detection sensitivity and report greater intensity and irritation sensation at stimulus detection than the asymptomatic wearers. Room temperature pneumatic esthesiometry may help to better understand the process of sensory adaptation to CL wear.

Association Between Contact Lens Discomfort and Pre-lens Tear Film Kinetics.

The relationship between contact lens wettability and comfort has been extensively evaluated; however, a direct correlation between the characteristics of the pre-lens tear film and the symptoms associated with contact lens discomfort has yet to be established. In addition, there is relatively limited knowledge relating to the entire tear film kinetics during the inter-blink period in contact lens wearers. The purpose of this analysis was to identify the characteristics of the pre-lens tear film kinetics that may be associated with the symptoms of contact lens discomfort. The study population comprised 202 soft (hydrogel and silicone hydrogel) contact lens wearers attending pre-screening visits at the OTG-i research clinic. All participants completed the Ocular Surface Disease Index (OSDI) questionnaire and the tear film was quantified via post hoc, masked analysis of high definition digital Tearscope videos recorded at the visit. The tear film kinetics of the least symptomatic wearers (OSDI lowest quintile scores, n = 45) were compared to the tear film kinetics of the most symptomatic wearers (OSDI highest quintile scores, n = 43). The hypothesis tested was that the tear film kinetics of asymptomatic wearers were better than tear film kinetics of symptomatic wearers. The distribution of lens types worn was as follows: Daily Disposable 46.5%, 1-Month Replacement 39.6%, and 2-Week Replacement 13.6%. 48.2% of lenses were silicone hydrogel and 51.8% hydrogel. Symptomatic wearers had a shorter break-up time (4.7 s vs. 6.0 s; p = 0.003), lesser surface coverage by the tear film during the interblink period (95.1% vs. 98.5%; p < 0.001) and greater surface exposure at the time of the blink (9.4% vs. 3.9%; p = 0.001). The current study demonstrated that the tear film kinetics of asymptomatic and symptomatic contact lens wearers were different, the findings supporting the hypothesis of poorer tear film kinetics for symptomatic than asymptomatic wearers in a general contact lens wearing population.

Time Course of Changes in Goblet Cell Density in Symptomatic and Asymptomatic Contact Lens Wearers.

To investigate longitudinal changes in goblet cell density (GCD) in contact lens (CL) wearers who do and do not develop symptoms of dry eye (DE). Sixty healthy individuals fitted with daily disposable hydrogel CLs and 23 age-balanced non-CL-wearing controls underwent assessment using the 5-item dry eye questionnaire, noninvasive tear film break-up time measurement, ocular surface assessment, and phenol red thread test evaluation. Laser scanning confocal microscopy (LSCM) and conjunctival impression cytology (CIC) were used to assess GCD at baseline and follow-up visits at 1 week and 1 and 6 months. After 1 week, all CL wearers were categorized as those who were and were not symptomatic based on responses to the CL dry eye questionnaire-8 (CLDEQ-8). A linear mixed-model was used to examine changes in GCD over time. The global mean GCD of the 83 participants at baseline (before CL wear) was 476 ± 41 and 467 ± 52 cells/mm2 using LSCM and CIC, respectively. After 6 months of CL wear, GCD was reduced by approximately 13% and 29% in asymptomatic (N = 29) and symptomatic (N = 17) CL wearers (all P < 0.001), respectively, observed with both LSCM and CIC. Contact lens wear induces a reduction of GCD over 6 months, which is exacerbated in those with DE symptoms. Either LSCM or CIC can be used to assess GCD in the conjunctiva.

P08.27 Results of a 2014 qld trial of pharmacy accessed testing forchlamydia trachomatisvia retail self-test uri swab postal specimen kits

Background Chlamydia is the most common Sexually Transmissible Infection in Australia, with 23,535 notifications for the first quarter of 2015, more than half of which occurring in the 15 to 25 age group. More than 80% of this high risk age group presenting to a general practice at least once annually, however rates of testing are low at 12.5% for females and 3.7% for males. International and Australian studies have suggested pharmacy involvement in testing. Piloting access through Australia’s 5,450 pharmacies is essential to reduce the incidence and long-term consequences of chlamydia through early detection, treatment of asymptomatic infection and contact tracing. Method A 9-month pilot of a retail self-test kit through 18 community pharmacies in the Brisbane Metro North region of Queensland. Each kit contained a uri swab, instructions, reply post envelope, pathology bag and form, and information on chlamydia. The consumer indicated preferred option for return of results. Results Of 109 kits purchased, 39.4% were returned for processing, with 16.3% of these returning a reactive result. 18% of returned samples were purchased by consumers under the age of 18, 53.5% between 18 – 29 year and the remainder aged over 30 years. All reactive results were subsequently treated. Conclusion This presentation will discuss integrating community pharmacy into any comprehensive Australian chlamydia testing program. Pharmacies are already providers of sexual health products, including contraception, pregnancy tests and Emergency Hormonal Contraception (EHC), where approximately 400,000 units of EHC provided each year. They are well placed for access to Chlamydia testing over extended hours, providing an additional confidential option access Chlamydia testing with the capacity to increase sexual health awareness and de-stigmatise chlamydia screening. Disclosure of interest statement This pilot was a collaboration of the Pharmacy Guild of Australia QLD Branch and Metro North Hospital and Health Service, funded by Metro North Brisbane Medicare Local.

Comparative Analysis of Tear Film Levels of Inflammatory Mediators in Contact Lens Users

ABSTRACTPurpose: To compare tear films levels of various inflammatory cytokines in asymptomatic contact lens (CL) users. CL users of rigid gas-permeable CLs (RGPCL) (group 1) or silicone hydrogel CLs (SiHCL) (group 2) were compared with non-CL-using healthy subjects (group 3).Materials and Methods: Tear samples were collected from subjects in each group after ensuring that there were no complications secondary to CL wear in the CL-wearing participants. Tear-film levels of interleukins (ILs)-1β, -6, and -8; granulocyte-macrophage colony-stimulating factor (GM-CSF) (using the Luminex method); and leukotriene B4 (LTB4) (using the ELISA method) were determined. Cytokine levels were compared among the three groups using analysis-of-variance (ANOVA) and Kruskall–Wallis tests.Results: There were significant differences in concentrations of IL-1β, GM-CSF and LTB4 among the three groups (p = 0.002, p = 0.021 and p = 0.009, respectively), as shown by the Kruskall–Wallis test comparing all three groups for the three cytokines. There were no significant differences for IL-6 and IL-8 (p = 0.079 and 0.094, respectively) when all three groups were compared.Conclusions: There were substantial statistically significant differences between RGPCL users, SiHCL users and control subjects in levels of tear film cytokines. Although CL users were asymptomatic, changes in tear-film levels of several important inflammatory mediators revealed that a chronic inflammatory process occurs during CL wear.

P153 Watching the tv:trichomonas vaginalisnaat testing in an inner city sexual health clinic: Abstract P153 Table 1

<h3>Introduction</h3> <i>Trichomonas vaginalis </i>(TV) is the commonest curable STI worldwide. UK prevalence is comparatively lower but TV remains an important cause of genital symptoms. National guidelines recommend NAATs for TV testing due to their high sensitivity. Since 2012 we have utilised Gen-Probe APTIMA TV assays for symptomatic females, males with recurrent urethritis and contacts. <h3>Aims</h3> Assess the effectiveness of our current TV NAAT testing practice. <h3>Methods</h3> Retrospective casenote review of patients tested for TV in an inner city sexual health clinic between 01/01/14–31/03/14. <h3>Results</h3> 961 (882F, 79M) patients were included. Median age was 24 (range 15–67), 445 (46.3%) were White British. 6 (7.6%) of the men were MSM. 28 (2.9%) patients were TV NAAT positive (21F, 7M). 5 of them attended as TV contacts. 11 TV-infected females had positive microscopy. Comparing diagnostic modalities microscopy had inferior sensitivity (=0.524) but excellent specificity (=1) and NPV (=0.986). All TV-positive men were either symptomatic (4) or an asymptomatic contact (3). The TV-positive and TV-negative cohorts were compared: TV incidence was significantly associated with increasing age, Black Caribbean ethnicity and attending as a contact; concurrent STI diagnoses and evident symptoms were not. <h3>Conclusion</h3> Our data demonstrates the superior sensitivity of NAATs over microscopy. Extending screening to asymptomatic patients is not warranted. We continue to focus TV testing on known at-risk populations.

Fungal isolation from disinfectant solutions of contact lens storage cases among asymptomatic users.

To investigate the incidence of fungal contamination of store disinfectant solutions contained in contact lens storage cases belonging to asymptomatic contact lens users. Asymptomatic contact lens users were asked to bring their storage cases, lenses included, without having opened the lid of the cup after placing lenses inside. The following information was recorded: age, sex, type of refractive error, contact lens material, schedule of wear, and brand of disinfectant solution. Included subjects had to comply with lens handling, cleaning, and replacement instructions given by the manufacturer or their attending optometrist. One sample per cup of contact lens case was collected using a sterile syringe. Samples were cultured on proper media for 96 hr at 35°C. Fungi were identified to species level by standard methodology. A total of 216 samples were collected from 117 contact lens storage cases. All participants were using monthly disposable hydrogel lenses on a daily wear basis. Seven fungal species were isolated from 15 specimens (6.9%) collected from 12 storage cases (10.2%). These included one Fusarium solani, four Aspergillus niger, two Aspergillus fumigatus, five Candida parapsilosis, one Candida tropicalis, one Rhodotorula rubra, and one F. solani in combination with Candida guilliermondii. Disinfectant solutions containing hydrogen peroxide were found to be less effective than various alternative solutions in eliminating fungal species. The results of this study show that even when contact lens users report compliance for handling, cleaning, and replacement according to the manufacturer's instructions, the potential risk of contact lens-related fungal keratitis still remains.

Clinical and biochemical tear lipid parameters in contact lens wearers.

Alterations in tear film lipids may be important in modulating discomfort during contact lens wear. This study investigates associations between clinical and biological components of the lipid layer and seeks to determine the effect of lipid supplementation on contact lens wear comfort. Participants were grouped into symptomatic (n = 10) and asymptomatic (n = 10) contact lens wearers according to the Contact Lens Dry Eye Questionnaire. After 6 hours of lens wear, noninvasive surface drying time (NISDT) and the lipid layer grade were assessed using a Tearscope. Basal tears were collected using a microcapillary tube and assayed for concentration and activity of the secretory phospholipase A2 enzyme and concentration of the lipid aldehyde malondialdehyde. Mass spectrometry was used to characterize the tear lipidome. In the second phase, a liposomal spray (Tears Again, BioRevive) or a saline spray was sprayed over the upper eyelids of each subject during their down gaze and during lens wear. Noninvasive surface drying time and ocular comfort were obtained soon after spraying and again at 2 and 6 hours after the initial spray. Statistical tests included the Student t test, repeated-measures analysis of variance, and the Pearson correlation test where appropriate. Noninvasive surface drying time was lower (p = 0.01) in symptomatic (4.5 ± 0.6 seconds) than in asymptomatic (9.9 ± 3.1 seconds) contact lens wearers. The mole percentage of wax esters in the total lipidome increased with NISDT (R = 0.70, p = 0.01). Secretory phospholipase A2 enzyme activity in tears was associated with higher levels of malondialdehyde (R = 0.65, p = 0.01) and shorter NISDT (R = 0.84, p = 0.001). Noninvasive surface drying time reduced over the time course for the saline spray (p = 0.01) but did not reduce until the 6-hour time point with the liposomal spray. With liposomal spray, NISDT was higher (p = 0.03) immediately after instillation compared with 6 hours later (9.5 ± 1.9 vs. 5.2 ± 2.1 seconds). A longer NISDT was associated with improved ocular comfort for those using the liposomal spray (R = 0.25, p = 0.005) but not with saline. Degraded lipids and a lower mole percentage of wax esters in the tear film may be associated with a lower NISDT. Lipid supplements may improve ocular comfort during lens wear by increasing NISDT.

Control of carbapenemase-producing Klebsiella pneumoniae: a region-wide intervention.

Starting in 2010, there was a sharp increase in infections caused by Klebsiella pneumoniae resistant to carbapenems in the Emilia-Romagna region in Italy. A region-wide intervention to control the spread of carbapenemase-producing K. pneumoniae (CPKP) in Emilia-Romagna was carried out, based on a regional guideline issued in July 2011. The infection control measures recommended to the Health Trusts (HTs) were: phenotypic confirmation of carbapenemase production, active surveillance of asymptomatic carriers and contact isolation precautions for carriers. A specific surveillance system was activated and the implementation of control measures in HTs was followed up. A significant linear increase of incident CPKP cases over time (p<0.001) was observed at regional level in Emilia-Romagna in the pre-intervention period, while the number of cases remained stable after the launch of the intervention (p=0.48). Considering the patients hospitalised in five HTs that provided detailed data on incident cases, a downward trend was observed in incidence after the release of the regional guidelines (from 32 to 15 cases per 100,000 hospital patient days). The spread of CPKP in Emilia-Romagna was contained by a centrally-coordinated intervention. A further reduction in CPKP rates might be achieved by increased compliance with guidelines and specific activities of antibiotic stewardship.

Full‐length genome characterization and genetic relatedness analysis of hepatitis A virus outbreak strains associated with acute liver failure among children

Clinical infection by hepatitis A virus (HAV) is generally self-limited but in some cases can progress to liver failure. Here, an HAV outbreak investigation among children with acute liver failure in a highly endemic country is presented. In addition, a sensitive method for HAV whole genome amplification and sequencing suitable for analysis of clinical samples is described. In this setting, two fatal cases attributed to acute liver failure and two asymptomatic cases living in the same household were identified. In a second household, one HAV case was observed with jaundice which resolved spontaneously. Partial molecular characterization showed that both households were infected by HAV subtype IA; however, the infecting strains in the two households were different. The HAV outbreak strains recovered from all cases grouped together within cluster IA1, which contains closely related HAV strains from the United States commonly associated with international travelers. Full-genome HAV sequences obtained from the household with the acute liver failure cases were related (genetic distances ranging from 0.01% to 0.04%), indicating a common-source infection. Interestingly, the strain recovered from the asymptomatic household contact was nearly identical to the strain causing acute liver failure. The whole genome sequence from the case in the second household was distinctly different from the strains associated with acute liver failure. Thus, infection with almost identical HAV strains resulted in drastically different clinical outcomes.