Migration and determinants of health : clinical epidemiological characteristics of migrants in Malta (2010-11)

Background Over recent years Malta has experienced a growing influx of migrants from Africa. With the aim of defining demographic characteristics and assessing the prevalence of conditions of public health significance among asylum seekers in Malta, a clinical research study was implemented in the framework of the European Union project ‘Mare nostrum’. Methods From August 2010 to June 2011 a dermatologist and an infectious diseases specialist performed general and specialist health assessment of migrants hosted in open centres. Results Migrants included in the study were 2216, 82.7% were males, their mean age was 25 years and 70.1% were from Somalia. Out of the total females, 42.5% had undergone some type of Female Genital Mutilation/Cutting. A total of 5077 diagnoses were set, most common were skin diseases (21.9%), respiratory diseases (19.8%) and gastro-enteric diseases (14.2%), whereas 31% of migrants reported good health conditions. Conclusions Immigrants have a lower morbidity burden compared with their fellow countrymen living in the origin country. However, living conditions during the journey, in transit countries and after arrival can influence their health status. The present study provides a comprehensive picture of this growing population that is in need for health promotion, mental health services and fair policy planning.peer-reviewe

Prevalence of latent tuberculosis, syphilis, hepatitis B and C among asylum seekers in Malta

Background: In the last few years, Malta has witnessed increasing immigration flows from the Libyan coasts. Public health policies are focused on screening migrants for tuberculosis, whereas no systematic actions against STIs are implemented. The aim of this study is to define the epidemiological profile of asylum seekers in Malta as regards syphilis, hepatitis B, C and latent tuberculosis, thus supporting screening policies. Methods: Five hundred migrants living in open centres were screened between December 2010 and June 2011. Results: 83.2% of people was from Somalia, 81.2% males, average age 26.5 years. The tuberculin skin test (TST) was positive in 225 migrants (45%). Latent syphilis was diagnosed in 11 migrants, hepatitis C in 3 and 31 migrants were HBsAg positive. Conclusion: Systematic screening for asymptomatic migrants in Malta is not recommended for hepatitis C and syphilis, given the low prevalence observed. On the contrary, it should be considered for hepatitis B. TST could be indicated as the first step of a two step screening for migrants from countries with high TB incidence. Efficacy and cost-effectiveness could be achieved by further targeting screening to specific subgroups at higher risk of reactivation, such as people living with HIV and subjects affected by chronic diseases.peer-reviewe

A multi-country comparative study of two treponemal tests for the serodiagnosis of Syphilis amongst Men Who Have Sex with Men (MSM):Chemo-luminescent assay vs Treponema pallidum particle agglutination assay

Introduction:International guidelines recommend routine screening for syphilis amongst keypopulations and vulnerable populations using tests detecting treponemal and nontreponemalantibodies. Whilst treponemal tests have high sensitivities and specificities,they differ regarding subjective or objective interpretation, throughput and workload.CLIAs are cost- and time-effective automated methods for detecting treponemalantibodies. The TPPA has been considered the “gold standard” treponemal assay,however, this includes a highly manual procedure, low throughput and subjectiveinterpretation. The present multi-country study evaluated the ADVIA Centaur® SyphilisCLIA assay compared to the reference SERODIA-TP·PA® for the serodiagnosis ofsyphilis amongst MSM.Method:1,485 MSM were enrolled in Brighton (UK), Malta, and Verona (Italy) as part of a largerWHO multi-country and multi-site ProSPeRo study. Serum was tested with the CLIAassay and TP·PA, in accordance with the manufacturers’ instructions, for a first roundof validation. A second round of validation was carried out for discrepant results thatwere additionally tested with both Western Blot and an Immunoblot.Sensitivity, specificity, positive and negative predictive value (PPV and NPV), likelihoodratios (positive/negative), and the Diagnostic Odds Ratio (DOR)/pre-post-testprobability were calculated.Results:Out of 1,485 eligible samples analysed in the first phase, the SERODIATP·PA identified 360 positive and 1,125 negative cases. The CLIA assay identified 366positives, missclassifying one TPPA-positive sample. In the second phase, the CLIAresulted in 1 false negative and 4 false positive results. Considering the syphilis studyprevalence of 24% (95% CI: 22-26.7), The sensitivity of the ADVIA Centaur® SyphilisCLIA assay was 99.7% (95% CI: 98.5-100), and the specificity was 99.4% (95% CI:98.7-99.7). The ROC area values were 0.996 (95% CI: 0.992-0.999), and both the PPVand NPV values were above 98%Conclusions:The CLIA assay showed similar performance compared to the SERODIA-TP·PA.Considering the study is based on QUADAS principles and with a homogeneouspopulation, results are also likely to be generalisable to MSM population but potentiallynot applicable to lower prevalence populations routinely screened for syphilis. Theautomated CLIA treponemal assay confirmed to be accurate and appropriate forroutine initial syphilis screening, i.e. when the reverse testing algorithm is applied

Standardised protocol for a prospective cross-sectional multicentre clinic-based evaluation of two dual point-of-care tests for the screening of HIV and syphilis in men who have sex with men, sex workers and pregnant women

Introduction Dual point-of-care tests (POCTs) for detecting antibodies to HIV and syphilis have been developed for use with venous whole blood, serum/plasma or finger-prick capillary whole blood. Several tests are commercially available showing encouraging performance compared with ‘gold-standard’ reference tests in laboratory-based studies. However, data on their performance in the field are limited. This prospective cross-sectional study will conduct a clinic-based evaluation to assess the performance characteristics and acceptability to end-users of two dual HIV/syphilis POCTs for the screening of HIV and syphilis among men who have sex with men (MSM), sex workers (SWs) and pregnant women (PW). This master protocol outlines the overall research approach that will be used in seven countries. Method and analysis MSM, SWs and PW presenting at clinic evaluation sites in high, low and middle-income countries will be enrolled. The (WHO preapproved) POCTs to be evaluated are SD Bioline HIV/Syphilis Duo (Abbott) and Dual Path Platform HIV-Syphilis Assay (Chembio). Finger-prick blood will be collected to perform POCTs and compared with laboratory results (venepuncture blood). Procedures will be carried out by trained healthcare staff and tests performed according to the manufacturers’ directions. Sample size was calculated based on local prevalence of HIV and syphilis. The sensitivity, specificity, positive and negative predictive values for each POCT will be calculated. The study is ongoing with recruitment expected to be completed in all countries by mid to late 2021. Ethics and dissemination This core protocol was independently peer reviewed and approved by the Research Project Review Panel (RP2) of the WHO Department of Sexual and Reproductive Health and Research and by the WHO Ethics Review Committee (ERC). The protocol has been adapted to individual countries and approved by RP2, ERC and institutional review boards at each site. Results will be disseminated through peer-reviewed journals and relevant conferences

Clinic-based evaluation of the dual Xpert CT/NG assay on the GeneXpert System for screening for extragenital chlamydial and gonococcal infections amongst men who have sex with men

Abstract Background Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections have increased globally. Asymptomatic infections represent a significant risk of long-term complications. Men who have sex with men (MSM) are disproportionally affected, underscoring the need to offer screening programmes to this population. CT/NG Point of Care Testing (POCT) constitutes a strategic tool to improve the continuum of STI care, however extensive real-life evaluations amongst at risk populations are lacking. The aim of this study is to estimate the GeneXpert CT/NG assay performance and usability for CT and NG at genital and extragenital sites for screening amongst MSM. Methods This study was a multi-site sexual health clinic-based evaluation (Italy, Malta and Peru) with consecutive enrolment. A first void urine sample (divided in two aliquots), two oropharyngeal and two anorectal swabs were collected for each study participant. One specimen set (one for each anatomical site) was tested with the dual index test (Cepheid) at the clinics by the healthcare staff, the other set with FDA/CE approved Nucleic Acid Amplification Tests (NAATs) at the laboratory. Clinical sites and reference laboratories participated in an internal and external quality control programme. Sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values for each anatomical site were estimated using a meta-analytic approach. Results One thousand seven hundred two MSM were recruited across all clinical sites for a total of 5049 biological specimens. NG and CT were respectively detected in 274 and 287 of samples. Overall, the NG POCT sensitivity and specificity was 91.43% and 99.75% in urine (LR + 372.80, LR- 0.09), 89.68% and 99.55% in rectal specimens (LR + 197.30, LR- 0.10) and 75.87% and 98.77% at the pharynx respectively (LR + 61.94, LR- 0.24). The CT component of the POCT sensitivity was 84.82% and specificity 99.63% in urine (LR + 228.68, LR- 0.15), 78.07% and 99.19% respectively on rectal site (LR + 96.23, LR-0.22), 67.79% and 99.88% respectively at pharyngeal site (LR + 554.89, LR- 0.32). 95.95% of MSM reported to be willing to wait for POCT results and no provider reported difficulties in terms of performance or interpretation of the results of the Xpert CT/NG. Conclusion Rapid turnaround time, ease of use and high acceptability make the Xpert CT/NG testing system a strategic tool for increasing testing frequency, reaching those not yet tested and offering the possibility of immediate treatment if needed. The assay showed good negative likelihood ratios and confirms its use to rule out CT/NG infections. Sensitivity varied across sites and pathogens. Periodic staff training at the testing sites should be mandatory

External quality assessment to support the WHO ProSPeRo study for the evaluation of two dual HIV/syphilis point-of-care tests in seven countries

Abstract Background Sexually transmitted infections (STIs) such as syphilis and HIV remain to be a significant public health issue worldwide. Dual rapid point-of-care tests (POCTs) have shown promise for detecting antibodies to HIV and syphilis but have not been fully evaluated in the field. Our study supported the WHO ProSPeRo study on Sexually Transmitted Infection Point-of-Care Testing (STI POCT) by providing external quality assessment (EQA) for HIV and syphilis testing in reference laboratories and their associated clinical sites in seven countries. Methods HIV/syphilis serum liquid and dried tube specimen (DTS) panels were prepared by CDC. Liquid panels were distributed to the reference laboratories for three rounds of testing using commercially and locally available laboratory-based serological tests. DTS panels were sent to the clinical testing sites for 8 rounds of POC testing using the Abbott SD BIOLINE HIV/Syphilis Duo test (hereafter referred to as SD BIOLINE) and the Chembio Dual Path Platform (DPP) HIV-Syphilis assay. EQA panels were tested at CDC using the Rapid Plasma Reagin (RPR) test and the Treponema pallidum Particle Agglutination assay (TP-PA) for syphilis antibodies. Genetic Systems HIV-1/HIV-2 Plus O EIA, Geenius HIV Supplemental Assay and the Oraquick Advance HIV test were used to detect HIV antibodies in the EQA panels. Results from the reference laboratories and POCT sites were compared to those obtained at the CDC and a percentage agreement was calculated. Results Qualitative RPR and TP-PA performed at the reference laboratories demonstrated 95.4–100% agreement with CDC results while quantitative RPR and TP-PA tests demonstrated 87.7% and 89.2% agreement, respectively. A 93.8% concordance rate was observed for qualitative HIV testing in laboratories. EQA testing at clinical sites using dual tests showed 98.7% and 99.1% agreement for detection of HIV antibodies and eight out of 10 sites had > 95.8% agreement for syphilis testing. However, two clinical sites showed only 65.0–66.7% agreement for SD BIOLINE and 84.0–86.7% for DPP, respectively, for syphilis testing. Conclusions Overall, laboratories demonstrated high EQA performance in this study. Both HIV/syphilis POCTs gave expected results in the clinic-based evaluations using DTS. However, testing errors were identified in a few testing sites suggesting the necessity for continuous training and monitoring the quality of POC testing

Quality control and external quality assessment for the independent clinic-based evaluation of point-of-care testing to detect Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis in eight countries

Abstract Background Sexually transmitted infections caused by Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Trichomonas vaginalis (TV) remain significant global health problems. The World Health Organization (WHO) has recently conducted a multi-faceted, multi-country validation study (ProSPeRo), which included an evaluation of the Xpert CT/NG and Xpert TV assays on the GeneXpert system (Cepheid, Sunnyvale, Ca., USA) in clinic-based settings across eight countries. To support the study, a training and quality management system was implemented and evaluated. Methods A comprehensive training program for the study was developed. Quality control (QC) and external quality assessment (EQA) samples were provided by an accredited quality assurance provider. QC testing was conducted at 14 point-of-care testing (POCT) clinics, while EQA samples were tested by the POCT sites and a reference laboratory supporting each clinic. Results For QC testing, concordance with the expected results for CT and NG was > 99% and rates of unsuccessful tests were  94%) for all analytes, but this cohort (which used GeneXpert systems) exhibited a high rate of unsuccessful TV tests. All but one of these unsuccessful tests was subcategorised as ‘invalid’. Conclusions The high level of concordance for QC and EQA testing confirm that the trained operators at the POC clinical sites were competent to conduct POC testing and that the training and quality systems implemented for the ProSPeRo study were effective. The quality materials used were satisfactory for CT and NG but exhibited poor performance for TV testing on the GeneXpert system. The WHO should continue to work with industry and EQA providers to provide improved materials that are reliable, stable and cost effective for quality management, as it seeks to rollout molecular-based STI POCT in non-laboratory-based settings. Trial registration Ethics approval to conduct the ProSPeRo study was granted by the WHO Ethics Review Committee