Last data update: May 06, 2024. (Total: 46732 publications since 2009)
Records 1-30 (of 94 Records) |
Query Trace: Mock P[original query] |
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Strengthening Bordetella pertussis genomic surveillance by direct sequencing of residual positive specimens
Peng Y , Williams MM , Xiaoli L , Simon A , Fueston H , Tondella ML , Weigand MR . J Clin Microbiol 2024 e0165323 Whole-genome sequencing (WGS) of microbial pathogens recovered from patients with infectious disease facilitates high-resolution strain characterization and molecular epidemiology. However, increasing reliance on culture-independent methods to diagnose infectious diseases has resulted in few isolates available for WGS. Here, we report a novel culture-independent approach to genome characterization of Bordetella pertussis, the causative agent of pertussis and a paradigm for insufficient genomic surveillance due to limited culture of clinical isolates. Sequencing libraries constructed directly from residual pertussis-positive diagnostic nasopharyngeal specimens were hybridized with biotinylated RNA "baits" targeting B. pertussis fragments within complex mixtures that contained high concentrations of host and microbial background DNA. Recovery of B. pertussis genome sequence data was evaluated with mock and pooled negative clinical specimens spiked with reducing concentrations of either purified DNA or inactivated cells. Targeted enrichment increased the yield of B. pertussis sequencing reads up to 90% while simultaneously decreasing host reads to less than 10%. Filtered sequencing reads provided sufficient genome coverage to perform characterization via whole-genome single nucleotide polymorphisms and whole-genome multilocus sequencing typing. Moreover, these data were concordant with sequenced isolates recovered from the same specimens such that phylogenetic reconstructions from either consistently clustered the same putatively linked cases. The optimized protocol is suitable for nasopharyngeal specimens with diagnostic IS481 Ct < 35 and >10 ng DNA. Routine implementation of these methods could strengthen surveillance and study of pertussis resurgence by capturing additional cases with genomic characterization. |
A comparative analysis of potential aerosol exposure in a wide-body aircraft cabin using tracer gas and fluorescent particles
Mahmoud S , Bennett J , Jones B , Hosni M . Int J Vent 2023 We compare two aerosol surrogate tracers in aircraft cabins for breathing and coughing sources: tracer gas collected in the ACER Boeing 767 mock-up and fluorescent particles collected in an actual Boeing 767 aircraft by the US Transportation Command (TRANSCOM). Each source was located individually in window and middle seats. Exposure generally decreased with source distance. A window seat breathing source resulted in good agreement between datasets for exposure (as percent of release) for the TRANSCOM hangar-AFT testing mode, which corresponds to the 11-row cabin ACER laboratory space. Average tracer gas exposure for a middle seat breathing source was higher in the ACER study than the fluorescent particle tracer exposure in the TRANSCOM study. Using a coughing source in a window seat, the exposure for the TRANSCOM data was higher within the first two rows from the source before decreasing to and tracking with the ACER levels, until increasing after about 5 m away. A similar trend was recorded for a middle seat coughing source with higher overall exposure for the TRANSCOM data. Sources of exposure variation between the studies include particle deposition. This work helps optimize aerosol dispersion research in aircraft cabins and provides some validation to the existing studies. © This work was authored as part of the Contributor’s official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law. |
Consensus pregnancy-related criteria for suicide and unintentional overdoses using a Delphi process
Smid MC , Vaughn P , Nowicki CC , Goodman DA , Zaharatos J , Campbell KA . Arch Womens Ment Health 2023 Suicide and unintentional overdose are leading manners of preventable death during and within a year of pregnancy. Recently, the Utah Maternal Mortality Review Committee (MMRC) developed 10 criteria to guide pregnancy-related classification of these deaths. Our objective was to (1) evaluate if consensus could be reached across experts in maternal mortality review when applying criteria to the determination of pregnancy-relatedness in mock MMRC case evaluation and (2) assess how additional case information shifted participants' determination of pregnancy-relatedness in these mock cases. We used a modified Delphi process to evaluate criteria for pregnancy-related suicides and unintentional overdose. The study team developed base case scenarios to reflect the 10 proposed criteria. Base scenarios varied in timing of death (prenatal or delivery, early postpartum (<6 months), late postpartum (6-12 months)) and level of additional information available (e.g., informant interviews, social media posts). Consensus in favor of a criterion was met when ≥75% of participants identified a case as pregnancy-related in at least 1 scenario. Fifty-eight participants, representing 48 MMRCs, reviewed scenarios. Of 10 proposed criteria, 8 reached consensus. Overall, participants classified 19.4% of base case scenarios as pregnancy-related, which increased to 56.8% with additional information. Pregnancy-related classification changed across timing of death and with availability of additional information (prenatal or delivery 27.7% versus 84.6%; early postpartum 30.0% versus 58.3%; late postpartum 0.0% versus 25.0%, respectively). We identified consensus supporting the application of 8 standardized criteria in MMRC determinations of pregnancy-relatedness among suicide and unintentional overdose deaths. |
Escaping the Fate of Sisyphus: Assessing Resistome Hybridization Baits for Antimicrobial Resistance Gene Capture (preprint)
Beaudry MS , Thomas JC , Baptista RP , Sullivan AH , Norfolk W , Devault A , Enk J , Kieran TJ , Rhodes OEJr , Perry KA , Rose LJ , Bayona-Vásquez NJ , Oladeinde A , Lipp EK , Sanchez S , Glenn TC . bioRxiv 2021 2021.07.20.452950 Finding, characterizing, and monitoring reservoirs for antimicrobial resistance (AMR) is vital to protecting public health. Hybridization capture baits are an accurate, sensitive, and cost-effective technique used to enrich and characterize DNA sequences of interest, including antimicrobial resistance genes (ARGs), in complex environmental samples. We demonstrate the continued utility of a set of 19,933 hybridization capture baits designed from the Comprehensive Antibiotic Resistance Database (CARD)v1.1.2 and Pathogenicity Island Database (PAIDB)v2.0, targeting 3,565 unique nucleotide sequences that confer resistance. We demonstrate the efficiency of our bait set on a custom-made resistance mock community and complex environmental samples to increase the proportion of on-target reads as much as >200-fold. However, keeping pace with newly discovered ARGs poses a challenge when studying AMR, because novel ARGs are continually being identified and would not be included in bait sets designed prior to discovery. We provide imperative information on how our bait set performs against CARDv3.3.1, as well as a generalizable approach for deciding when and how to update hybridization capture bait sets. This research encapsulates the full life cycle of baits for hybridization capture of the resistome from design and validation (both in silico and in vitro) to utilization and forecasting updates and retirement.Originality-Significance Statement This work is applicable to a wide range of research. It helps to define conditions under which hybridization capture is useful regarding not only antimicrobial resistance specifically, but also more generally how to assess the ongoing utility of existing bait sets - giving objective criteria for when and by what strategies baits should be updated. We also provide a method for quantifying and comparing antimicrobial resistance genes (ARGs) similar to what is used for RNAseq experiments. This approach improves comparison of ARGs across environments. Thus, the work provides an improved foundation for ARG future studies, while cutting across traditional areas of microbiology and extending beyond.Competing Interest StatementThe EHS DNA lab provides oligonucleotide aliquots and library preparation services at cost, including some oligonucleotides and services used in this manuscript (baddna.uga.edu). JE and AD were employed by, and thereby have financial interest in, Daicel Arbor Biosciences, who provided the in-solution capture reagents used in this work. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. |
Porcine fungal mock community analyses: Implications for mycobiome investigations
Arfken AM , Frey JF , Carrillo NI , Dike NI , Onyeachonamm O , Rivera DN , Davies CP , Summers KL . Front Cell Infect Microbiol 2023 13 928353 INTRODUCTION: The gut microbiome is an integral partner in host health and plays a role in immune development, altered nutrition, and pathogen prevention. The mycobiome (fungal microbiome) is considered part of the rare biosphere but is still a critical component in health. Next generation sequencing has improved our understanding of fungi in the gut, but methodological challenges remain. Biases are introduced during DNA isolation, primer design and choice, polymerase selection, sequencing platform selection, and data analyses, as fungal reference databases are often incomplete or contain erroneous sequences. METHODS: Here, we compared the accuracy of taxonomic identifications and abundances from mycobiome analyses which vary among three commonly selected target gene regions (18S, ITS1, or ITS2) and the reference database (UNITE - ITS1, ITS2 and SILVA - 18S). We analyze multiple communities including individual fungal isolates, a mixed mock community created from five common fungal isolates found in weanling piglet feces, a purchased commercial fungal mock community, and piglet fecal samples. In addition, we calculated gene copy numbers for the 18S, ITS1, and ITS2 regions of each of the five isolates from the piglet fecal mock community to determine whether copy number affects abundance estimates. Finally, we determined the abundance of taxa from several iterations of our in-house fecal community to assess the effects of community composition on taxon abundance. RESULTS: Overall, no marker-database combination consistently outperformed the others. Internal transcribed space markers were slightly superior to 18S in the identification of species in tested communities, but Lichtheimia corymbifera, a common member of piglet gut communities, was not amplified by ITS1 and ITS2 primers. Thus, ITS based abundance estimates of taxa in piglet mock communities were skewed while 18S marker profiles were more accurate. Kazachstania slooffiae displayed the most stable copy numbers (83-85) while L. corymbifera displayed significant variability (90-144) across gene regions. DISCUSSION: This study underscores the importance of preliminary studies to assess primer combinations and database choice for the mycobiome sample of interest and raises questions regarding the validity of fungal abundance estimates. |
Efficacy of Do-It-Yourself air filtration units in reducing exposure to simulated respiratory aerosols
Derk RC , Coyle JP , Lindsley WG , Blachere FM , Lemons AR , Service SK , Martin SB Jr , Mead KR , Fotta SA , Reynolds JS , McKinney WG , Sinsel EW , Beezhold DH , Noti JD . Build Environ 2023 229 109920 Many respiratory diseases, including COVID-19, can be spread by aerosols expelled by infected people when they cough, talk, sing, or exhale. Exposure to these aerosols indoors can be reduced by portable air filtration units (air cleaners). Homemade or Do-It-Yourself (DIY) air filtration units are a popular alternative to commercially produced devices, but performance data is limited. Our study used a speaker-audience model to examine the efficacy of two popular types of DIY air filtration units, the Corsi-Rosenthal cube and a modified Ford air filtration unit, in reducing exposure to simulated respiratory aerosols within a mock classroom. Experiments were conducted using four breathing simulators at different locations in the room, one acting as the respiratory aerosol source and three as recipients. Optical particle spectrometers monitored simulated respiratory aerosol particles (0.3-3 μm) as they dispersed throughout the room. Using two DIY cubes (in the front and back of the room) increased the air change rate as much as 12.4 over room ventilation, depending on filter thickness and fan airflow. Using multiple linear regression, each unit increase of air change reduced exposure by 10%. Increasing the number of filters, filter thickness, and fan airflow significantly enhanced the air change rate, which resulted in exposure reductions of up to 73%. Our results show DIY air filtration units can be an effective means of reducing aerosol exposure. However, they also show performance of DIY units can vary considerably depending upon their design, construction, and positioning, and users should be mindful of these limitations. |
What Can We Learn about the Bias of Microbiome Studies from Analyzing Data from Mock Communities?
Li M , Tyx RE , Rivera AJ , Zhao N , Satten GA . Genes (Basel) 2022 13 (10) It is known that data from both 16S and shotgun metagenomics studies are subject to biases that cause the observed relative abundances of taxa to differ from their true values. Model community analyses, in which the relative abundances of all taxa in the sample are known by construction, seem to offer the hope that these biases can be measured. However, it is unclear whether the bias we measure in a mock community analysis is the same as we measure in a sample in which taxa are spiked in at known relative abundance, or if the biases we measure in spike-in samples is the same as the bias we would measure in a real (e.g., biological) sample. Here, we consider these questions in the context of 16S rRNA measurements on three sets of samples: the commercially available Zymo cells model community; the Zymo model community mixed with Swedish Snus, a smokeless tobacco product that is virtually bacteria-free; and a set of commercially available smokeless tobacco products. Each set of samples was subject to four different extraction protocols. The goal of our analysis is to determine whether the patterns of bias observed in each set of samples are the same, i.e., can we learn about the bias in the commercially available smokeless tobacco products by studying the Zymo cells model community? |
ROCker Models for Reliable Detection and Typing of Short-Read Sequences Carrying β-Lactamase Genes.
Zhang SY , Suttner B , Rodriguez RLm , Orellana LH , Conrad RE , Liu F , Rowell JL , Webb HE , Williams-Newkirk AJ , Huang A , Konstantinidis KT . mSystems 2022 7 (3) e0128121 Identification of genes encoding β-lactamases (BLs) from short-read sequences remains challenging due to the high frequency of shared amino acid functional domains and motifs in proteins encoded by BL genes and related non-BL gene sequences. Divergent BL homologs can be frequently missed during similarity searches, which has important practical consequences for monitoring antibiotic resistance. To address this limitation, we built ROCker models that targeted broad classes (e.g., class A, B, C, and D) and individual families (e.g., TEM) of BLs and challenged them with mock 150-bp- and 250-bp-read data sets of known composition. ROCker identifies most-discriminant bit score thresholds in sliding windows along the sequence of the target protein sequence and hence can account for nondiscriminative domains shared by unrelated proteins. BL ROCker models showed a 0% false-positive rate (FPR), a 0% to 4% false-negative rate (FNR), and an up-to-50-fold-higher F1 score [2 × precision × recall/(precision + recall)] compared to alternative methods, such as similarity searches using BLASTx with various e-value thresholds and BL hidden Markov models, or tools like DeepARG, ShortBRED, and AMRFinder. The ROCker models and the underlying protein sequence reference data sets and phylogenetic trees for read placement are freely available through http://enve-omics.ce.gatech.edu/data/rocker-bla. Application of these BL ROCker models to metagenomics, metatranscriptomics, and high-throughput PCR gene amplicon data should facilitate the reliable detection and quantification of BL variants encoded by environmental or clinical isolates and microbiomes and more accurate assessment of the associated public health risk, compared to the current practice. IMPORTANCE Resistance genes encoding β-lactamases (BLs) confer resistance to the widely prescribed antibiotic class β-lactams. Therefore, it is important to assess the prevalence of BL genes in clinical or environmental samples for monitoring the spreading of these genes into pathogens and estimating public health risk. However, detecting BLs in short-read sequence data is technically challenging. Our ROCker model-based bioinformatics approach showcases the reliable detection and typing of BLs in complex data sets and thus contributes toward solving an important problem in antibiotic resistance surveillance. The ROCker models developed substantially expand the toolbox for monitoring antibiotic resistance in clinical or environmental settings. |
Transactional sex, HIV and health among young cisgender men and transgender women who have sex with men in Thailand
Weir BW , Dun C , Wirtz AL , Mon SHH , Qaragholi N , Chemnasiri T , Pattanasin S , Wukwicha W , Varangrat A , DunneEF , Holtz TH , Janyam S , Jin H , Linjongrat D , Mock PA , Thigpen MC , Rooney JF , Sullivan PS , Hickey AC , Sirivongrangson P , Beyrer C , Poonkasetwattana M . Ann Epidemiol 2022 72 1-8 PURPOSE: To examine how recent sex work is identified and the HIV risk factors and service needs among Thai cisgender men who have sex with men (MSM) and transgender women (TGW) who exchange sex. METHODS: MSM and TGW in Bangkok and Pattaya who exchanged sex in the last year (n= 890) were recruited through social media, outreach, and word-of-mouth. Recent sex exchange was based on the primary question, "in the last 30 days, have you sold or traded sex"; secondary questions (regarding income source and client encounters) were also investigated. RESULTS: Overall, 436 (48%) participants engaged in sex work in the last 30 days; among those, 270 (62%) reported exchanging sex by the primary question, and 160 (37%) based on secondary questions only. Recent sex exchange was associated with gonorrhea, syphilis, discussing PrEP with others, and using condoms, alcohol, methamphetamine, amyl nitrate, and Viagra®. Exchanging sex based on secondary questions only was associated with being in a relationship, social media recruitment, less recent anal intercourse, and not discussing PrEP. CONCLUSIONS: Thai MSM and TGW who exchange sex need regular access to HIV/STI prevention, testing, and treatment services, and multiple approaches to assessing sex work will help identify and serve this diverse and dynamic population. |
HIV prevalence and incidence among men who have sex with men and transgender women in Bangkok, 2014-2018: Outcomes of a consensus development initiative
van Griensven F , Phanuphak N , Manopaiboon C , Dunne EF , Colby DJ , Chaiphosri P , Ramautarsing R , Mock PA , Guadamuz TE , Rangsin R , Benjamaneepairoj K , Na Nakorn P , Vannakit R , de Lind van Wijngaarden JW , Avery M , Mills S . PLoS One 2022 17 (1) e0262694 To reach its goal of ending AIDS by 2030, Thailand has adopted antiretroviral treatment as prevention and HIV pre-exposure prophylaxis for men who have sex with men (MSM) and transgender women (TGW) as its core HIV control strategy. However, in the absence of reliable epidemiologic indicators, the impact of these policies on the course of the HIV epidemic in these groups remains unknown. To help answer this question, we formulated an HIV epidemic consensus initiative for Bangkok, Thailand, to analyze epidemiologic and program data and reach agreement between experts and stakeholders on the evolving state of the HIV epidemic among MSM and TGW. A customized Delphi process was used to consult and consolidate viewpoints of experts and stakeholders. Experts presented and discussed HIV prevalence and incidence data from recent and ongoing studies among MSM and TGW in Bangkok (2014 to 2018) during a meeting with stakeholders representing government, donors, and civil society. Agreement about the course of the HIV epidemic among MSM and TGW was attained by voting consensus. Based on presented data, meeting participants agreed that HIV prevalence and incidence had decreased among Bangkok MSM from 2014 to 2018. Despite these declines, HIV prevalence and incidence were found to remain high. This was particularly the case among younger MSM. Participants agreed that there was no evidence for a decrease in HIV prevalence and incidence among Bangkok TGW. Introduction of antiretroviral treatment as prevention and HIV pre-exposure prophylaxis may have contributed to these declines. However, HIV prevalence and incidence remained high, and no signs of a decrease were reported among Bangkok TGW. At the current rate of new HIV infections in MSM and TGW, Thailand will not reach its goal of ending AIDS by 2030. This HIV consensus initiative may serve as a model for building agreement and advocacy on epidemiologic and program data and their implications for a large metropolitan city. |
West nile virus vaccination protects against usutu virus disease in mice
Salgado R , Hawks SA , Frere F , Vázquez A , Huang CYH , Duggal NK . Viruses 2021 13 (12) West Nile virus (WNV) and Usutu virus (USUV) are mosquito‐borne flaviviruses that can cause neuroinvasive disease in humans. WNV and USUV circulate in both Africa and Europe and are closely related. Due to antigenic similarity, WNV‐specific antibodies and USUV‐specific antibodies have the potential to bind heterologous viruses; however, it is unclear whether this interaction may offer protection against infection. To investigate how prior WNV exposure would influ-ence USUV infection, we used an attenuated WNV vaccine that contains the surface proteins of WNV in the backbone of a dengue virus 2 vaccine strain and protects against WNV disease. We hypothesized that vaccination with this attenuated WNV vaccine would protect against USUV in-fection. Neutralizing responses against WNV and USUV were measured in vitro using sera following vaccination. Sera from vaccinated CD‐1 and Ifnar1−/− mice cross‐neutralized with WNV and USUV. All mice were then subsequently challenged with an African or European USUV strain. In CD‐1 mice, there was no difference in USUV titers between vaccinated and mock‐vaccinated mice. However, in the Ifnar1−/− model, vaccinated mice had significantly higher survival rates and significantly lower USUV viremia compared to mock‐vaccinated mice. Our results indicate that exposure to an attenuated form of WNV protects against severe USUV disease in mice and elicits a neutralizing response to both WNV and USUV. Future studies will investigate the immune mechanisms responsible for the protection against USUV infection induced by WNV vaccination, providing critical insight that will be essential for USUV and WNV vaccine development. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. |
Escaping the fate of Sisyphus: assessing resistome hybridization baits for antimicrobial resistance gene capture.
Beaudry MS , Thomas JC , Baptista RP , Sullivan AH , Norfolk W , Devault A , Enk J , Kieran TJ , Rhodes OEJr , Perry-Dow KA , Rose LJ , Bayona-Vásquez NJ , Oladeinde A , Lipp EK , Sanchez S , Glenn TC . Environ Microbiol 2021 23 (12) 7523-7537 Finding, characterizing and monitoring reservoirs for antimicrobial resistance (AMR) is vital to protecting public health. Hybridization capture baits are an accurate, sensitive and cost-effective technique used to enrich and characterize DNA sequences of interest, including antimicrobial resistance genes (ARGs), in complex environmental samples. We demonstrate the continued utility of a set of 19 933 hybridization capture baits designed from the Comprehensive Antibiotic Resistance Database (CARD)v1.1.2 and Pathogenicity Island Database (PAIDB)v2.0, targeting 3565 unique nucleotide sequences that confer resistance. We demonstrate the efficiency of our bait set on a custom-made resistance mock community and complex environmental samples to increase the proportion of on-target reads as much as >200-fold. However, keeping pace with newly discovered ARGs poses a challenge when studying AMR, because novel ARGs are continually being identified and would not be included in bait sets designed prior to discovery. We provide imperative information on how our bait set performs against CARDv3.3.1, as well as a generalizable approach for deciding when and how to update hybridization capture bait sets. This research encapsulates the full life cycle of baits for hybridization capture of the resistome from design and validation (both in silico and in vitro) to utilization and forecasting updates and retirement. |
HIV and syphilis prevalence among transgender women and men who have sex with men, Silom Community Clinic, Bangkok, Thailand, 2017-2019
Pattanasin S , Griensven FV , Mock PA , Sukwicha W , Kongpechsatit O , Krasan C , O'Connor S , Hickey AC , Ungsedhapand C , Woodring JV , Connor S , Chitwarakorn A , Dunne EF . AIDS Care 2021 34 (10) 1-9 We assessed HIV and syphilis infection among MSM and TGW attending Silom Community Clinic from 2017 to 2019. Walk-in and referral clients completed a registration application including a question on gender identity. We compared the prevalence of HIV, syphilis, and HIV and syphilis coinfection among TGW and MSM. In a total of 1050 clients, 276 (26.3%) were TGW and 774 (74.7%) were MSM. Among TGW clients, HIV prevalence was 29.8%, syphilis prevalence was 38.4%, and coinfection prevalence was 18.5%. Comparing prevalence among TGW to MSM, the adjusted prevalence ratio (aPR) for HIV was 1.8 (95% CI:1.4-2.3), for syphilis was 1.2 (95% CI:1.0-1.4), and for HIV and syphilis coinfection was 2.1 (95% CI:1.4-2.9). The prevalence of syphilis was higher than HIV among TGW, with a PR of 1.3 (95% CI:1.1-1.6), and among MSM, with a PR of 1.4 (95% CI:1.2-1.7). TGW age 15-21 years had an HIV prevalence of 16.9% and syphilis prevalence of 30.8%. After adjusting for age, referral, and sexual behaviors, TGW remain significantly associated with HIV and syphilis prevalence. There is a substantial burden of HIV and HIV/syphilis co-infection among TGW. HIV/STI prevention are needed for TGW, including linkage to HIV care. |
Enhancing U.S. local, state, and federal preparedness through simulated interactive tabletop exercises of a mock antibiotic-resistant gonorrhea outbreak, 2018-2019
Schlanger K , Black JM , Smith M , Ridpath A , Crause C , Holderman JL , Henderson K , Hardrick H , Pham CD , Howard G , Kirkcaldy RD . Sex Transm Dis 2021 48 S174-S179 BACKGROUND: Responding effectively to outbreaks of antibiotic-resistant gonorrhea (ARGC) in the future will likely prove challenging. Tabletop exercises (TTXs) may assist local, state, and federal public health officials evaluate existing ARGC outbreak response plans, strengthen preparedness and response effectiveness, and identify critical gaps to address prior to an outbreak. METHODS: In 2018-2019, CDC collaborated with state partners to develop and implement TTXs to simulate a public health emergency involving an ARGC outbreak. Prior to the TTXs, two state-local health department pairs developed ARGC outbreak response plans. During each one-day exercise (in Indiana and Illinois), participants discussed roles, clinical management, public health response, and communication based on pre-developed response plans. Observers identified outbreak response strengths and gaps, and participants completed feedback forms. RESULTS: Forty-one (Illinois) and 48 people (Indiana) participated in each TTX, including: STD clinical staff, laboratorians, public health infectious disease program staff, and CDC observers. Strengths and gaps varied by jurisdiction, but identified gaps included: (1) local access to gonorrhea culture and timely antimicrobial susceptibility testing (AST), (2) protocols for clinical management of suspected treatment failures, (3) communication plans, and (4) clarity regarding state and local responsibilities. CDC observers identified opportunities to provide national-level technical assistance, foster local AST, and develop further response guidance. TTX summary reports were used to guide modifications to local response plans to address gaps. CONCLUSIONS: The TTXs allowed participants to practice responding to a simulated public health emergency and may have enhanced local response capacity. CDC made TTX implementation materials publicly available. |
A real-time multiplex PCR assay for detection of the causative agents of rat bite fever, Streptobacillus moniliformis and zoonoticStreptobacillus species.
Kelly AJ , Ivey ML , Gulvik CA , Humrighouse BW , McQuiston JR . Diagn Microbiol Infect Dis 2021 100 (2) 115335 Rat bite fever (RBF) caused by Streptobacillus moniliformis has been described as a diagnostic challenge. While it has a favorable prognosis with treatment, timely diagnosis is hindered by the lack of culture-free identification methods. Here we present a multiplex real-time PCR assay that detects the zoonotic Streptobacillus spp. as well as differentiate the primary causative agent of RBF, Streptobacillus moniliformis. The performance of this assay was evaluated using mock clinical specimens for blood, serum, and urine. Analytical sensitivity was determined to be 3-4 genome equivalents (GE)/µl for the zoonotic Streptobacillus spp. target, and 1-2 GE/µl for the S. moniliformis specific target. The assay correctly detected only the intended targets with no cross-reactivity identified. The pathogen was detected in all spiked matrices and not detected in the negative non-spiked specimens. This rapid diagnostic assay may permit quicker diagnosis of RBF patients. |
Performance evaluation of fungal DNA PCR amplification from formalin-fixed paraffin-embedded tissue for diagnosis; experience of a tertiary reference laboratory.
Lysen C , Silva-Flannery L , Zaki SR , Gary JM , Lockhart SR . Mycoses 2021 64 (6) 603-611 BACKGROUND: Diagnosis of invasive fungal infections from formalin-fixed paraffin-embedded (FFPE) tissues by PCR amplification is a developing technology. One of the difficulties of establishing a validated protocol for this testing is that the gold standard, culture, is much less sensitive than the test being validated. OBJECTIVES: To validate FFPE PCR as a refence laboratory identification methodology in the absence of abundant gold standard specimens. METHODS: In this validation, PCR from FFPE tissue was compared to other diagnostic methods for genus/species identification. Four different groups of correlative data from FFPE tissues were used to validate this procedure. Thirteen specimens had culture or serology results and FFPE PCR results, 49 specimens had both immunohistochemistry (IHC) identification and FFPE PCR results, 118 specimens had histological evidence of fungal elements, 64 of which also had FFPE PCR results, and 36 fungal mock tissues or fungal negative tissues were used. RESULTS: The sensitivity determined from the tissues with positive fungal histopathology was 54%. The specificity of the cases for which there were both culture and FFPE PCR results was 100%. For the correlation with IHC, the specificity was 98%. For the mock tissues and fungal-negative tissues the calculated analytical sensitivity was 94%, specificity was 95% and accuracy was 94%. CONCLUSIONS: By uniquely combining various data sources this study provides a comprehensive framework for how validation can be achieved in the absence of a gold standard and outlines the excellent performance of PCR from FFPE tissue, despite relatively the low sensitivity when compared to histopathology. |
HIV incidence among men who have sex with men and transgender women in four provinces in Thailand
Kritsanavarin U , Bloss E , Manopaiboon C , Khawcharoenporn T , Harnlakon P , Vasanti-Uppapokakorn M , Kitwattanachai P , Naprasert S , Phiphatthananon T , Visavakum P , Jetsawang B , Mock PA . Int J STD AIDS 2020 31 (12) 1154-1160 The HIV epidemic in Thailand is concentrated in key populations, with the highest rates in men who have sex with men (MSM) and transgender women (TG). Previous studies of HIV incidence in these groups have been limited mostly to Bangkok. We measured HIV incidence in MSM and TG in four provinces and evaluated factors associated with incident infections to inform public health prevention efforts. An analysis was conducted using data collected during a prospective observational cohort study during April 2015-May 2018 in outpatient clinics in five hospitals across four provinces in Thailand. MSM and TG aged ≥18 years, who were not known to be HIV-infected, and who reported anal intercourse with a male or TG without a condom in the past six months were enrolled. Participants were followed-up every 6 months for 18 months with questionnaires and HIV testing. A total of 40 HIV seroconversions occurred during follow-up, resulting in an HIV incidence of 3.5 per 100 person-years (95% CI 2.5, 4.8). Multivariate analyses indicated that identifying as gay (adjusted hazard ratio [AHR] 4.9; 95% CI 1.7-14.2), having receptive anal sex in the past six months (AHR 3.6; 95% CI 1.4-9.5), using alcohol (AHR 3.3; 95% CI 1.3-8.3), and taking alkyl nitrites (AHR 4.4; 95% CI 1.7-11.2) in the past six months were all independently associated with HIV infection. Overall this study found a lower HIV incidence in the highest risk population in Thailand compared with similar studies in Bangkok. Accelerated prevention efforts are needed to make the goal of 'zero new infections' possible in Thailand. |
Amylin, Abeta42, and amyloid in VZV vasculopathy cerebrospinal fluid and infected vascular cells
Bubak AN , Beseler C , Como CN , Coughlan CM , Johnson NR , Hassell JE , Burnet AM , Mescher T , Schmid DS , Coleman C , Mahalingam R , Cohrs RJ , Boyd TD , Potter H , Shilleh AH , Russ HA , Nagel MA . J Infect Dis 2020 223 (7) 1284-1294 BACKGROUND: VZV vasculopathy is characterized by persistent arterial inflammation leading to stroke. Studies show that VZV induces amyloid formation that may aggravate vasculitis. Thus, we determined if VZV central nervous system (CNS) infection produces amyloid. METHODS: Aβ peptides, amylin, and amyloid were measured in CSF from 16 VZV vasculopathy subjects and 36 stroke controls. To determine if infection induced amyloid deposition, mock- and VZV-infected quiescent primary human perineurial cells (qHPNCs), present in vasculature, were analyzed for intracellular amyloidogenic transcripts/proteins and amyloid. Supernatants were assayed for amyloidogenic peptides and ability to induce amyloid formation. To determine amylin's function during infection, amylin was knocked down with siRNA and viral cDNA quantitated. RESULTS: Compared to controls, VZV vasculopathy CSF had increased amyloid that positively correlated with amylin and anti-VZV antibody levels; Aβ40 was reduced and Aβ42 unchanged. Intracellular amylin, Aβ42, and amyloid were seen only in VZV-infected qHPNCs. VZV-infected supernatant formed amyloid fibrils following addition of amyloidogenic peptides. Amylin knockdown decreased viral cDNA. CONCLUSIONS: VZV infection increased levels of amyloidogenic peptides and amyloid in CSF and qHPNCs, indicating that VZV-induced amyloid deposition may contribute to persistent arterial inflammation in VZV vasculopathy. In addition, we identified a novel proviral function of amylin. |
Recent declines in HIV infections at Silom Community Clinic Bangkok, Thailand corresponding to HIV prevention scale up: an open cohort assessment 2005-2018
Pattanasin S , van Griensven F , Mock PA , Sukwicha W , Winaitham S , Satumay K , O'Connor S , Hickey AC , Siraprapasiri T , Woodring JV , Sirivongrangson P , Holtz TH , Dunne EF . Int J Infect Dis 2020 99 131-137 OBJECTIVES: We assessed HIV-1 infection among men who have sex with men (MSM) attending Silom Community Clinic (SCC) in Bangkok, Thailand from 2005-2018. Since 2014, Thailand increased implementation of HIV prevention strategies including pre-exposure prophylaxis and Treatment as Prevention. METHODS: MSM attending SCC were tested for HIV using rapid tests. We assessed trends in HIV prevalence, incidence and compared incidence before and after 2014. RESULTS: From 2005-2018, 14,034 clients attended SCC for HIV testing. The HIV prevalence increased from 19.2% in 2005-2006 to 34.0% in 2010, remained stable until 2016 and decreased to 17.2% in 2018 (p < 0.0001). The HIV incidence was 4.1 per 100 person-years (PY), with an inverted U-shape trend and a peak in 2009 (p < 0.0001). Incidence among young MSM aged 13-21 years remained high at 10.0 per 100 PY. Among those aged 22-29 years, lower incidence was found from Q 3 2016, with a relative risk reduction of 46.2% (p <0.001); and a similar reduction among those aged >/= 30 years from Q4 2014, corresponding to scale up of HIV prevention strategies. CONCLUSION: We find a decline in HIV infection among MSM. However, incidence remained high among young MSM. |
Estimating the impact of HIV combination prevention in men who have sex with men, the Bangkok MSM Cohort Study, Thailand
Pattanasin S , Cadwell BL , Smith DK , Sukwicha W , Mock PA , Wimonsate W , Ungsedhapand C , Sirivongrangson P , Dunne EF , Thigpen MC . Int J STD AIDS 2020 31 (7) 637-641 In Thailand, pre-exposure prophylaxis (PrEP) is recommended for human immunodeficiency virus (HIV) prevention among at-risk men who have sex with men (MSM). We modeled the impact of PrEP and condom use as independent and combined interventions on the estimated number of HIV infections among a hypothetical population of 10,000 MSM in Bangkok, Thailand. Our model demonstrated a 92% (95% confidence interval 89.7, 94.2) reduction in HIV infections among Thai MSM who took daily PrEP and self-reported using condoms correctly and consistently (100% condom use). Increased use of PrEP and condoms likely would have a substantial impact on the HIV epidemic in Thailand. |
Repeat symptomatic Neisseria gonorrhoeae infections among men who have sex with men in Bangkok, Thailand, 2006-2016
Pattanasin S , Holtz TH , Ungsedhapand C , Tongtoyai J , Chonwattana W , Sukwicha W , Sirivongrangson P , Mock PA , Chitwarakorn A , Dunne EF . Int J STD AIDS 2020 31 (6) 533-540 We analyzed the incidence and predictors of symptomatic repeat Neisseria gonorrhoeae (NG) infection among men who have sex with men (MSM) enrolled in the Bangkok MSM Cohort Study. Thai MSM aged ≥18 years were enrolled during 2006–2010 and followed every four months. At baseline, participants were screened for rectal and urethral NG and Chlamydia trachomatis (CT) infections using nucleic acid amplification testing (NAAT), rectal and pharyngeal NG by culture, and pharyngeal CT by NAAT. During follow-up, symptomatic participants were tested for NG infection by NAAT and Gram stain of rectal or urethral specimens. Among 1464 participants without NG infection at the baseline visit and having at least one follow-up visit, 11.2% (164/1464) developed symptomatic NG infection, for a total of 251 infections. Symptomatic repeat NG infection occurred in 28.0% (46/164) of participants. The incidence rate was 3.9 cases per 100 person-years. Baseline predictors of repeat symptomatic NG were as follows: unknown human immunodeficiency virus (HIV) status despite history of HIV testing, previous sexually transmitted infection diagnosis by physician, insertive-only anal intercourse without a condom, amyl nitrate use at baseline, CT infection at baseline, age 18–24 years, and being a student; HIV infection at baseline or during the study period was also associated with repeat symptomatic NG infection. © The Author(s) 2020. |
Testing the effectiveness and cost-effectiveness of a combination HIV prevention intervention among young cisgender men who have sex with men and transgender women who sell or exchange sex in Thailand: Protocol for the Combination Prevention Effectiveness Study
Wirtz AL , Weir BW , Mon SHH , Sirivongrangson P , Chemnasiri T , Dunne EF , Varangrat A , Hickey AC , Decker MR , Baral S , Okanurak K , Sullivan P , Valencia R , Thigpen MC , Holtz TH , Mock PA , Cadwell B , Adeyeye A , Rooney JF , Beyrer C . JMIR Res Protoc 2020 9 (1) e15354 BACKGROUND: Pre-exposure prophylaxis (PrEP) is highly effective in the prevention of HIV acquisition, particularly for men who have sex with men (MSM). Questions remain on the benefits of PrEP and implementation strategies for those at occupational risk of HIV acquisition in sex work, as well as on methods to support adherence among young people who initiate PrEP. OBJECTIVE: The Combination Prevention Effectiveness study for young cisgender MSM and transgender women (TGW) aims to assess the effectiveness and cost-effectiveness of a combination intervention among HIV-uninfected young MSM and TGW engaged in sex work in Thailand. METHODS: This open-label, nonrandomized assessment compares the relative effectiveness of a combination prevention intervention with and without daily oral emtricitabine and tenofovir disoproxil fumarate (Truvada) PrEP with SMS-based adherence support. HIV-uninfected young MSM and TGW aged 18 to 26 years in Bangkok and Pattaya who self-report selling/exchanging sex at least once in the previous 12 months are recruited by convenience sampling and peer referral and are eligible regardless of their intent to initiate PrEP. At baseline, participants complete a standard assessment for PrEP eligibility and may initiate PrEP then or at any time during study participation. All participants complete a survey and HIV testing at baseline and every 3 months. Participants who initiate PrEP complete monthly pill pickups and may opt-in to SMS reminders. All participants are sent brief weekly SMS surveys to assess behavior with additional adherence questions for those who initiated PrEP. Adherence is defined as use of 4 or more pills within the last 7 days. The analytic plan uses a person-time approach to assess HIV incidence, comparing participant time on oral PrEP to participant time off oral PrEP for 12 to 24 months of follow-up, using a propensity score to control for confounders. Enrollment is based on the goal of observing 620 person-years (PY) on PrEP and 620 PY off PrEP. RESULTS: As of February 2019, 445 participants (417 MSM and 28 TGW) have contributed approximately 168 PY with 95% (73/77) retention at 12 months. 74.2% (330/445) of enrolled participants initiated PrEP at baseline, contributing to 134 PY of PrEP adherence, 1 PY nonadherence, and 33 PY PrEP nonuse/noninitiation. Some social harms, predominantly related to unintentional participant disclosure of PrEP use and peer stigmatization of PrEP and HIV, have been identified. CONCLUSIONS: The majority of cisgender MSM and TGW who exchange sex and participate in this study are interested in PrEP, report taking sufficient PrEP, and stay on PrEP, though additional efforts are needed to address community misinformation and stigma. This novel multilevel, open-label study design and person-time approach will allow evaluation of the effectiveness and cost-effectiveness of combination prevention intervention in the contexts of both organized sex work and exchanged sex. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/15354. |
Assessing costs of a hypertension management program: An application of the HEARTS costing tool in a program planning workshop in Thailand
Husain MJ , Allaire BT , Hutchinson B , Ketgudee L , Srisuthisak S , Yueayai K , Pisitpayat N , Nugent R , Datta BK , Joseph KT , Kostova D . J Clin Hypertens (Greenwich) 2019 22 (1) 111-117 The HEARTS technical package, a part of the Global Hearts Initiative to improve cardiovascular health globally, is a strategic approach for cardiovascular disease prevention and control at the primary care level. To support the evaluation of costs associated with HEARTS program components, a costing tool was developed to evaluate the incremental cost of program implementation. This report documents an application of the HEARTS costing tool during a costing workshop prior to the initiation of a HEARTS pilot program in Thailand's Phothong District, 2019-2020. During the workshop, a mock exercise was conducted to estimate the expected costs of the pilot study. The workshop application of the tool underscored its applicability to the HEARTS program planning process by identifying cost drivers associated with individual program elements. It further illustrated that by supporting disaggregation of costs into fixed and variable categories, the tool can inform the scalability of pilot projects to larger populations. Lessons learned during the initial development and application of the costing tool can inform future HEARTS evaluation efforts. |
Alterations in blood chemistry levels associated with Nipah virus disease in the Syrian hamster model
Genzer SC , Welch SR , Scholte FEM , Harmon JR , Coleman-McCray JD , Lo MK , Montgomery JM , Nichol ST , Spiropoulou CF , Spengler JR . J Infect Dis 2019 221 S454-S459 Nipah virus ([NiV] family Paramyxoviridae, genus Henipavirus) infection can cause severe respiratory and neurological disease in humans. The pathophysiology of disease is not fully understood, and it may vary by presentation and clinical course. In this study, we investigate changes in blood chemistry in NiV-infected Syrian hamsters that survived or succumbed to disease. Increased sodium and magnesium and decreased albumin and lactate levels were detected in animals euthanized with severe clinical disease compared with mock-infected controls. When subjects were grouped by clinical syndrome, additional trends were discernable, highlighting changes associated with either respiratory or neurological disease. |
Partnerships involved in public health testing for Zika virus in Florida, 2016
Heberlein-Larson L , Gillis LD , Morrison A , Scott B , Cook M , Cannons A , Quaye E , White S , Cone M , Mock V , Schiffer J , Lonsway D , Petway M , Otis A , Stanek D , Hamilton J , Crowe S . Public Health Rep 2019 134 43s-52s The emergence of Zika virus in the Americas in 2015 and its association with birth defects and other adverse health outcomes triggered an unprecedented public health response and a demand for testing. In 2016, when Florida exceeded state public health laboratory capacity for diagnostic testing, the state formed partnerships with federal and commercial laboratories. Eighty-two percent of the testing (n = 33 802 of 41 008 specimens) by the laboratory partners, including Florida's Bureau of Public Health Laboratories (BPHL; n = 13 074), a commercial laboratory (n = 19 214), and the Centers for Disease Control and Prevention (CDC; n = 1514), occurred from July through November 2016, encompassing the peak period of local transmission. These partnerships allowed BPHL to maintain acceptable test turnaround times of 1 to 4 days for nucleic acid testing and 3 to 7 days for serologic testing. Lessons learned from this response to inform future outbreaks included the need for early planning to establish outside partnerships, adding specimen triage strategies to surge plans, and integrating state and CDC information systems. |
HIV-1 genetic diversity to estimate time of infection and infer adherence to pre-exposure prophylaxis.
Council OD , Ruone S , Mock PA , Khalil G , Martin A , Curlin ME , McNicholl JM , Heneine W , Leelawiwat W , Choopanya K , Vanichseni S , Cherdtrakulkiat T , Anekvorapong R , Martin M , Garcia-Lerma JG . AIDS 2019 33 (15) 2299-2307 OBJECTIVE: To estimate time of HIV infection in participants from the Bangkok Tenofovir Study (BTS) with daily oral tenofovir disoproxil fumarate (TDF) for pre-exposure prophylaxis (PrEP) and relate infection with adherence patterns. DESIGN: We used the diversity structure of the virus population at the first RNA-positive sample to estimate the date of infection, and mapped these estimates to medication diaries obtained under daily directly observed therapy (DOT). METHODS: HIV genetic diversity was investigated in all 17 PrEP breakthrough infections and in 16 placebo recipients. We generated 10 to 25 HIV env sequences from each participant by single genome amplification, and calculated time since infection (and 95% confidence interval) using Poisson models of early virus evolution. Study medication diaries obtained under daily DOT were then used to compute the number of missed TDF doses at the approximate date of infection. RESULTS: Fifteen of the 17 PrEP breakthrough infections were successfully amplified. Of these, 13 were initiated by a single genetic variant and generated reliable estimates of time since infection (median=47 [IQR=35] days). Eleven of these 13 were under daily DOT at the estimated time of infection. Analysis of medication diaries in these 11 participants showed 100% adherence in five, 90-95% adherence in two, 55% adherence in one, and non-adherence in three. CONCLUSIONS: We estimated time of infection in participants from BTS and found several infections when high levels of adherence to TDF were reported. Our results suggest that the biological efficacy of daily TDF against parenteral HIV exposure is not 100%. |
HIV-1 genetic diversity to estimate time of infection and infer adherence to preexposure prophylaxis.
Council OD , Ruone S , Mock PA , Khalil G , Martin A , Curlin ME , McNicholl JM , Heneine W , Leelawiwat W , Choopanya K , Vanichseni S , Cherdtrakulkiat T , Anekvorapong R , Martin M , Garcia-Lerma JG . AIDS 2019 33 (15) 2299-2307 OBJECTIVE: To estimate time of HIV infection in participants from the Bangkok Tenofovir Study (BTS) with daily oral tenofovir disoproxil fumarate (TDF) for pre-exposure prophylaxis (PrEP) and relate infection with adherence patterns. DESIGN: We used the diversity structure of the virus population at the first RNA-positive sample to estimate the date of infection, and mapped these estimates to medication diaries obtained under daily directly observed therapy (DOT). METHODS: HIV genetic diversity was investigated in all 17 PrEP breakthrough infections and in 16 placebo recipients. We generated 10 to 25 HIV env sequences from each participant by single genome amplification, and calculated time since infection (and 95% confidence interval) using Poisson models of early virus evolution. Study medication diaries obtained under daily DOT were then used to compute the number of missed TDF doses at the approximate date of infection. RESULTS: Fifteen of the 17 PrEP breakthrough infections were successfully amplified. Of these, 13 were initiated by a single genetic variant and generated reliable estimates of time since infection (median=47 [IQR=35] days). Eleven of these 13 were under daily DOT at the estimated time of infection. Analysis of medication diaries in these 11 participants showed 100% adherence in five, 90-95% adherence in two, 55% adherence in one, and non-adherence in three. CONCLUSIONS: We estimated time of infection in participants from BTS and found several infections when high levels of adherence to TDF were reported. Our results suggest that the biological efficacy of daily TDF against parenteral HIV exposure is not 100%. |
HPTN 067/ADAPT: Correlates of sex-related pre-exposure prophylaxis adherence, thai men who have sex with men, and transgender women, 2012-2013
Holtz TH , Chitwarakorn A , Hughes JP , Curlin ME , Varangrat A , Li M , Amico KR , Mock PA , Grant RM . J Acquir Immune Defic Syndr 2019 82 (2) e18-e26 BACKGROUND: We identified correlates of sex-related pre-exposure prophylaxis (PrEP) adherence in HPTN067/ADAPT, a phase 2, open-label feasibility study of daily and nondaily regimens of emtricitabine/tenofovir disoproxil fumarate (FTC/TDF)-based PrEP, among Thai men who have sex with men (MSM), and transgender women (TGW), Bangkok. METHODS: Participants were randomly assigned to one of three self-administered dosing regimens for 24 weeks: daily, time-driven, or event-driven. Demographic and behavioral information was obtained at screening. Pill-container opening was recorded with electronic dose monitoring, and self-reported information on PrEP use, sex events, and substance use was obtained during weekly interviews to confirm dose data. Sex-related PrEP adherence was calculated as the proportion of sex events covered by PrEP use (at least one tablet taken within 4 days before sex and at least one tablet taken within 24 hours after sex) to total sex events. We used multivariate modeling with sex event as the unit of analysis to evaluate correlates associated with sex-related PrEP adherence. RESULTS: Among 178 MSM and TGW, sex-related PrEP adherence was similar in the daily and time-driven arms (P = 0.79), both significantly greater than the event-driven arm (P = 0.02 compared to daily). Sex-related PrEP adherence by those reporting stimulant use (74.2%) was similar to those reporting other nonalcohol drug use (76.3%, P = 0.80), but lower than those reporting no substance use (84.6%, P = 0.04). In a multivariable model, randomization to the event-driven arm, a higher prestudy number of reported sex events, and use of stimulant drugs were associated with significantly lower sex-related PrEP adherence. CONCLUSION: Adherence was influenced by treatment schedule and adversely affected by nonalcoholic substance use. Regardless of these factors, Thai MSM and TGW maintained high adherence levels to oral PrEP dosing regimens and coverage of sexual exposures. |
HIV incidence and risk behaviours of people who inject drugs in Bangkok, 19952012
Martin M , Vanichseni S , Sangkum U , Mock PA , Leethochawalit M , Chiamwongpaet S , Pitisuttithum P , Kaewkungwal J , van Griensven F , McNicholl JM , Tappero JW , Mastro TD , Kittimunkong S , Choopanya K . EClinicalMedicine 2019 9 44-51 Background: Three consecutive prospective studies were conducted among people who inject drugs (PWID) from May 1995 through June 2012 in Bangkok, Thailand. We examined data from these studies to evaluate HIV incidence and explore trends in risk behaviours. Methods: We used data from a 1995–1998 cohort study, a 1999–2004 HIV vaccine trial, and a 2005–2012 HIV pre-exposure prophylaxis (PrEP) study to examine per-quarter trends in HIV incidence, using a restricted cubic spline function for time in a Poisson regression. We also examined temporal trends in HIV-associated risk behaviours. Findings: HIV incidence declined from 5.7 per 100 person-years during the cohort study, to 2.7 per 100 person-years in the vaccine trial, to 0.7 per 100 person-years among PrEP study placebo recipients. Incidence peaked at 12.1 per 100 person-years in 1996 and declined to < 1.0% during 2005–2012. Reports of injecting drugs and sharing needles also declined from the cohort study to the PrEP study (p < 0.0001). Heroin was the most common drug injected during the cohort study and the vaccine trial, but stimulants (e.g., methamphetamine) and sedatives (e.g., midazolam) were injected more often during the PrEP study. Interpretation: HIV incidence among PWID declined during 2005–2012. Several factors likely contributed to the decline, including decreases in the frequency of injecting and sharing, improved access to HIV testing and antiretroviral therapy, and the use of PrEP. Expanding access to effective HIV prevention tools can hasten control of the HIV epidemic among PWID. Funding: The Bangkok Metropolitan Administration and U.S. Centers for Disease Control and Prevention, Division of HIV/AIDS Prevention. |
Hepatitis C virus infection among people who inject drugs in Bangkok, Thailand, 2005-2010.
Martin M , Vanichseni S , Leelawiwat W , Anekvorapong R , Raengsakulrach B , Cherdtrakulkiat T , Sangkum U , Mock PA , Leethochawalit M , Chiamwongpaet S , McNicholl JM , Kittimunkong S , Curlin ME , Choopanya K . WHO South East Asia J Public Health 2019 8 (1) 50-55 Background: Approximately 1% of adults in Thailand are infected with hepatitis C virus (HCV). New direct-acting antiviral agents achieve sustained virologic responses in >95% of HCV-infected patients and are becoming available in countries around the world. To prepare for new HCV treatment options in Thailand, this study characterized HCV infections among people who inject drugs (PWID) in Bangkok. Methods: The Bangkok Tenofovir Study (BTS) was a pre-exposure prophylaxis trial conducted among PWID, 2005-2013. Blood specimens were randomly selected from PWID screened for the BTS, to test for anti-HCV antibody and HCV RNA. The HVR1 region was amplified by polymerase chain reaction, using multiplex primer sets with unique identifier sequences; amplification products were pooled in sets of 25; and consensus sequencing was performed to characterize individual HCV genotypes. Results: The median age of 3679 participants tested for anti-HCV antibody was 31 years, 3016 (82.0%) were male and 447 (12.2%) were HIV infected. The prevalence of anti-HCV antibody was 44.3%. The adjusted odds of testing positive for anti-HCV antibody were higher in men (adjusted odds ratio [aOR] 3.2, 95% confidence interval [CI] 2.4-4.3), those aged 40 years or older (aOR 2.7, 95% CI 2.1-3.5), those who had more than a primary school education (aOR 1.7, 95% CI 1.4-2.1), and those who tested HIV positive (aOR 5.2, 95% CI 3.7-7.4). HCV RNA was detected in 644 (81.3%) of the 792 anti-HCV antibody-positive specimens, yielding an HCV RNA-positive prevalence of 36.0% (95% CI 33.8-38.2). Among a random sample of 249 of the 644 specimens, 218 could be characterized, and the most common HCV subtypes were 1a (30.3%), 1b (12.8%), 3a (35.8%), 3b (6.9%) and 6n (8.7%). Conclusion: The prevalence of anti-HCV antibody among PWID was 44.3% and more than one third (36.0%) were HCV RNA positive. Genotypes 1, 3 and 6 accounted for all typable infections. As the government of Thailand considers introduction of direct-acting antiviral medications for people with hepatitis C, it will be important to ensure that the medications target these subtypes. |
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