scholarly journals Dealing with pre-exposure prophylaxis-associated condom migration: changing the paradigm for men who have sex with men

Sexual Health ◽  
2017 ◽  
Vol 14 (1) ◽  
pp. 106 ◽  
Author(s):  
Richard A. Crosby

The behavioural aspects of pre-exposure prophylaxis (PrEP) are challenging, particularly the issue of condom migration. Three vital questions are: (1) at the population-level, will condom migration lead to increases in non-viral sexually transmissible infections?; (2) how can clinic-based counselling best promote the dual use of condoms and PrEP?; and (3) in future PrEP trials, what are the ‘best practices’ that should be used to avoid type 1 and type 2 errors that arise without accounting for condom use behaviours? This communication piece addresses each question and suggests the risk of a ‘PrEP only’ focus to widening health disparities.

Sexual Health ◽  
2016 ◽  
Vol 13 (2) ◽  
pp. 196 ◽  
Author(s):  
Priya Loomba ◽  
Vickie Knight ◽  
Anna McNulty

Background This study aimed to describe oropharyngeal chlamydia (OCT) in gay and bisexually active men (GBM) attending a large urban sexual health clinic in Sydney and determine what proportion of cases would be missed if screening was not routine. Methods: Retrospective data were extracted for all GBM with a positive OCT result between 1 October 2012 and 31 April 2014. The control group consisted of patients who had a negative OCT result on their first visit during the study period, and each patient was only counted once. Results: A total of 74 of 2920 GBM (0.03, 95% CI: 0.02–0.03) were diagnosed with OCT. The 2920 GBM had a total of 11 226 OCT tests performed, demonstrating OCT test positivity of 0.006 (95% CI: 0.005–0.008). A total of 62 sexually transmissible infections (STIs) were diagnosed at other sites: 34 rectal chlamydia (CT), 12 throat gonorrohea (GC), 7 urine CT, 7 rectal GC, 1 infectious syphilis and 1 non-gonoccal urethritis (NGU) case. Of the 74 OCT cases, 56 (0.76, 95% CI: 0.64–0.85) were treated with Azithromycin; 51 (69%) as part of standard treatment for their STI co-infection (34 rectal CT, 12 throat GC, 7 urine CT, 7 rectal GC, 1 NGU case) and a further five (7%) were treated as contacts. The remaining 18 people (0.24, 95% CI: 0.15–0.36) would not have been treated unless they were tested specifically for OCT. Conclusion: Overall, two-thirds of the OCT cases received appropriate treatment and only a small number of cases would have been missed had routine screening not been performed. With an extremely low overall test positivity of 0.6%, screening for OCT at our service adds little to population level health control.


2020 ◽  
Author(s):  
Linwei Wang ◽  
Nasheed Moqueet ◽  
Anna Simkin ◽  
Jesse Knight ◽  
Huiting Ma ◽  
...  

ABSTRACTBackgroundHIV pre-exposure prophylaxis (PrEP) may change serosorting patterns. We examined the influence of serosorting on the population-level HIV transmission impact of PrEP, and how impact could change if PrEP users stopped serosorting.MethodsWe developed a compartmental HIV transmission model parameterized with bio-behavioural and HIV surveillance data among men who have sex with men in Canada. We separately fit the model with serosorting and without serosorting (random partner-selection proportional to availability by HIV-status (sero-proportionate)), and reproduced stable HIV epidemics (2013-2018) with HIV-prevalence 10.3%-24.8%, undiagnosed fraction 4.9%-15.8%, and treatment coverage 82.5%-88.4%. We simulated PrEP-intervention reaching stable coverage by year-1 and compared absolute difference in relative HIV-incidence reduction 10-year post-intervention (PrEP-impact) between: models with serosorting vs. sero-proportionate mixing; and scenarios in which PrEP users stopped vs. continued serosorting. We examined sensitivity of results to PrEP-effectiveness (44%-99%) and coverage (10%-50%).FindingsModels with serosorting predicted a larger PrEP-impact compared with models with sero-proportionate mixing under all PrEP-effectiveness and coverage assumptions (median (inter-quartile-range): 8.1%(5.5%-11.6%)). PrEP users” stopping serosorting reduced PrEP-impact compared with when PrEP users continued serosorting: reductions in PrEP-impact were minimal (2.1%(1.4%-3.4%)) under high PrEP-effectiveness (86%-99%); however, could be considerable (10.9%(8.2%-14.1%)) under low PrEP effectiveness (44%) and high coverage (30%-50%).InterpretationModels assuming sero-proportionate mixing may underestimate population-level HIV-incidence reductions due to PrEP. PrEP-mediated changes in serosorting could lead to programmatically-important reductions in PrEP-impact under low PrEP-effectiveness (e.g. poor adherence/retention). Our findings suggest the need to monitor sexual mixing patterns to inform PrEP implementation and evaluation.FundingCanadian Institutes of Health ResearchRESEARCH IN CONTEXTEvidence before this studyWe searched PubMed for full-text journal articles published between Jan 1, 2010, and Dec 31, 2017, using the MeSH terms “pre-exposure prophylaxis (PrEP)” and “homosexuality, male” and using key words (“pre-exposure prophylaxis” or “preexposure prophylaxis” or “PrEP”) and (“men who have sex with men” or “MSM”) in titles and abstracts. Search results (520 records) were reviewed to identify publications which examined the population-level HIV transmission impact or population-level cost-effectiveness of PrEP in high-income settings. We identified a total of 18 modelling studies of PrEP impact among men who have sex with men (MSM) and four studies were based on the same model with minor variations (thus only the most recent one was included). Among the 15 unique models of PrEP impact, three included serosorting. A total of nine models have assessed the individual-level behaviour change among those on PrEP and its influence on the transmission impact of PrEP. Specifically, the models examined increases in number of partners and reductions in condom use. Most models predicted that realistic increases in partner number or decreases in condom use would not fully offset, but could weaken, PrEP”s impact on reducing HIV transmission. We did not identify any study that examined the influence of serosorting patterns on the estimated transmission impact of PrEP at the population-level, or what could happen to HIV incidence if the use of PrEP changes serosorting patterns.Added value of this studyWe used a mathematical model of HIV transmission to estimate the influence of serosorting and PrEP-mediated changes in serosorting on the transmission impact of PrEP at the population-level among MSM. We found the impact of PrEP was higher under epidemics with serosorting, compared with comparable epidemics simulated assuming sero-proportionate mixing. Under epidemics with serosorting, when PrEP users stopped serosorting (while other men continue to serosort among themselves) we found a reduced PrEP impact compared with scenarios when PrEP users continued to serosort. The magnitude of reduction in PrEP impact was minimal if PrEP-effectiveness was high; however, could be programmatically-meaningful in the context of low PrEP-effectiveness (e.g., poor adherence or retention) and high PrEP coverage. To our knowledge, our study is the first to directly examine the influence of serosorting and PrEP-mediated changes in serosorting on the transmission impact of PrEP and its underlying mechanism.Implications of all the available evidenceOur findings suggest that models which do not consider baseline patterns of serosorting among MSM could potentially underestimate PrEP impact. In addition to monitoring individual-level behavioural change such as condom use, our findings highlight the need to monitor population-level sexual mixing patterns and their changes over time among MSM in the design and evaluation of PrEP implementation.


Author(s):  
Mark Harrison

This chapter describes types of errors as applied to Emergency Medicine, and in particular the Primary FRCEM examination. The chapter outlines the key details of type 1 errors and type 2 errors. This chapter is laid out exactly following the RCEM syllabus, to allow easy reference and consolidation of learning.


2020 ◽  
Vol 42 (5) ◽  
pp. 1041-1076
Author(s):  
Jeong-eun Kim ◽  
Yejin Cho ◽  
Youngsun Cho ◽  
Yeonjung Hong ◽  
Seohyun Kim ◽  
...  

AbstractThis study examines the effects of asymmetrical mappings of L2 sounds to L1 sounds on real-time processing of L2 phonology. L1-Korean participants completed a self-paced listening (SPL) task paired with a picture verification (PV) task, in which an English sentence was presented word by word along with a picture that matched or mismatched the sentence. In the critical region, an L2 vowel was deliberately replaced with the wrong vowel for two types of English vowel pairs: Type 1: English vowel pairs showing a one-to-one mapping to Korean counterparts (e.g., English: /i/ and /æ/ to Korean /i/ and /æ/, respectively); and Type 2: English vowel pairs showing a two-to-one mapping to a Korean counterpart (e.g., English /i/ and /ɪ/ to Korean /i/). We analyzed response times (RTs) and PV accuracy. Longer RTs were observed for Type 1 errors than Type 2 errors, indicating lower sensitivity to L2 vowels with two-to-one mapping to an L1 vowel. Also, PV accuracy was lower for the sentences containing Type 2 errors. These results suggest that asymmetrical L2-L1 sound mapping can affect learners’ processing of L2 phonological knowledge, which in turn can negatively affect their comprehension.


Sexual Health ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 56 ◽  
Author(s):  
Laia Fina ◽  
Amy L. Phillips ◽  
Adam T. Jones ◽  
Zoë M. Couzens ◽  
Rachel Drayton ◽  
...  

Background Pre-exposure prophylaxis (PrEP) was introduced in Sexual Health Services of the Welsh National Health Service (NHS Wales) in July 2017 as a 3-year pilot service. Methods: Data were collected through the pre-existing Sexual Health in Wales Surveillance System, to which codes were added to capture PrEP eligibility, outcome of offer of PrEP, reasons for declining and adherence. Eligibility categories were defined based on nationally agreed criteria: men who have sex with men (MSM) and transgender people at high risk of HIV acquisition; partners of HIV-positive individuals not known to be virally suppressed; and heterosexuals reporting condomless intercourse with a HIV-positive individual not known to be virally suppressed. Results: During the first 6 months, 516 people were eligible, 96% of which were MSM. Overall, 57% of those eligible (296/516) started PrEP. Reasons for declining PrEP were given by 88 (56%) of 157 people; 50 (57%) of whom did not believe themselves to be at risk. Of the available adherence assessments, 89% considered that all risk episodes had been covered. Persistence at 3 months was assessed for 141 people, of which 93 (66%) were still using PrEP. There were no HIV diagnoses in people taking PrEP during the first 6 months. Twenty-nine people were diagnosed with 37 episodes of sexually transmissible infections (STIs) while on PrEP. STI incidence was 105.7 per 100 person-years. Conclusions: The early trend indicates that implementation of PrEP is progressing as planned, and the service has been utilised by clients. This analysis can help refine implementation, inform planning and research around uptake, use and effect in Wales and internationally.


Sexual Health ◽  
2016 ◽  
Vol 13 (6) ◽  
pp. 555 ◽  
Author(s):  
Jason J. Ong ◽  
Andre Landika ◽  
Christopher K. Fairley ◽  
Catriona Bradshaw ◽  
Marcus Chen ◽  
...  

Background Non-occupational post-exposure prophylaxis (NPEP) is available to people with a potential risk for HIV exposure within the preceding 72 h. We sought to determine if men who have sex with men (MSM) and receive NPEP had a significantly different risk profile (before the preceding 72 h) from MSM not receiving NPEP. If this is the case, NPEP consultations may act as a cue for also discussing pre-exposure prophylaxis. Methods: We conducted a retrospective analysis to compare the demographic characteristics, sexual practices and clinical diagnoses of MSM who were NPEP users and those who were non-NPEP users attending Melbourne Sexual Health Centre from January 2008 to December 2014. Univariate and multivariate logistic regression models were used to examine the association between NPEP use and risk practices. Generalised estimating equations were used to adjust for within-individual correlations related to multiple visits of the same individual. Results: Of the 40 395 MSM consultations included in the study, 1776 consultations (4%) were related to NPEP prescription. NPEP prescribing was associated with ever having injected drugs (adjusted odds ratio (AOR) 1.8, 95% confidence interval (CI): 1.4–2.3), sex with males only (AOR 1.9, 95% CI: 1.6–2.3), more than three male partners in the past 3 months (AOR 1.5, 95% CI: 1.4–1.7) and inconsistent condom use with these partners within the past 3 months (AOR 2.1, 95% CI: 1.9–2.4). Sex workers (AOR 0.6, 95% CI: 0.3–0.9), and men reporting sex overseas within the past 12 months (AOR 0.7, 95% CI: 0.6–0.8) were less likely to receive NPEP. MSM who used NPEP were more likely to test positive for any sexually transmissible infection (AOR 1.2, 95% CI: 1.0–1.4). Conclusions: MSM receiving NPEP generally had a higher risk profile than MSM not requesting NPEP, indicating that NPEP was used by MSM at higher risk for HIV. Therefore, consultations for NPEP may be an opportune time for also discussing pre-exposure prophylaxis for HIV.


2012 ◽  
Vol 69 (4) ◽  
pp. 784-796 ◽  
Author(s):  
Robert C. Bailey ◽  
Garry Scrimgeour ◽  
David Coté ◽  
Dan Kehler ◽  
Simon Linke ◽  
...  

The effects on benthic macroinvertebrate communities of simulated degradation of streams enabled evaluation of the effects of starting condition, type of degradation, and biota descriptor on the type 1 and type 2 error rates of bioassessment. Benthic macroinvertebrate communities from five reference streams in the Fraser River basin (British Columbia, Canada) were used as the starting conditions of replicated simulations of the effects of suspended sediments in three temporal patterns (none, one-time severe, constant moderate). The dynamics of the simulated stream communities and the type 1 and type 2 errors associated with bioassessments, as described by (i) taxon richness, (ii) EPT (Ephemeroptera, Plecoptera, Trichoptera) richness, (iii) proportion of EPT individuals in the community, (iv) difference in composition from the median reference community (MCDist), (v) Simpson’s diversity, and (vi) Simpson’s equitability, depended on the combination of starting condition, simpact treatment, and the biota descriptor. To reduce type 1 and type 2 errors in bioassessments using the reference condition approach, bioassessment programs should include (i) matching of test and expected reference communities and refinement of the definition of reference condition and (ii) several biota descriptors that include measures of richness, tolerance, and community composition.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Umang Barvalia ◽  
Barkha Amlani ◽  
Ram Pathak

Amiodarone is an iodine-based, potent antiarrhythmic drug bearing a structural resemblance to thyroxine (T4). It is known to produce thyroid abnormalities ranging from abnormal thyroid function testing to overt hypothyroidism or hyperthyroidism. These adverse effects may occur in patients with or without preexisting thyroid disease. Amiodarone-induced thyrotoxicosis (AIT) is a clinically recognized condition commonly due to iodine-induced excessive synthesis of thyroid, also known as type 1 AIT. In rare instances, AIT is caused by amiodarone-induced inflammation of thyroid tissue, resulting in release of preformed thyroid hormones and a hyperthyroid state, known as type 2 AIT. Distinguishing between the two states is important, as both conditions have different treatment implications; however, a mixed presentation is not uncommon, posing diagnostic and treatment challenges. We describe a case of a patient with amiodarone-induced type 2 hyperthyroidism and review the current literature on the best practices for diagnostic and treatment approaches.


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