About

Dr. Paul C. Adamson is an Infectious Diseases physician and an Assistant Clinical Professor of Medicine in the Division of Infectious Diseases at the David Geffen School of Medicine at UCLA. He sees patients at the UCLA CARE Center, where he specializes in the treatment and prevention of HIV and other sexually transmitted infections (STIs). His research focuses on improving the diagnosis and treatment of STIs in global health settings, with an emphasis on antibiotic-resistant gonorrhea. Additionally, he participates in various COVID-19 related research and advocacy projects. Dr. Adamson received his medical degree from the UC San Francisco School of Medicine and completed his internship and residency training in Internal Medicine at Yale – New Haven Hospital/Yale University School of Medicine. He completed fellowship training in Infectious Diseases at UCLA. His academic background also includes undergraduate and Master’s degrees in Public Health from UC Berkeley. Outside of his professional work, he enjoys running, trying new restaurants, and baking sourdough bread. He is a member of several professional organizations, including the Infectious Diseases Society of America, the American Sexually Transmitted Diseases Association, and the American Board of Internal Medicine.

Research topics

• Medicine
• Artificial Intelligence
• Machine Learning
• Computer Science
• Algorithm
• Virology
• Internal medicine
• Intensive care medicine
• Immunology
• Environmental health
• Psychiatry
• Gynecology
• Biology
• Microbiology
• Pathology

Selected publications

• Clinical characteristics and symptoms associated with <i>Mycoplasma genitalium</i> infections among heterosexual men in Hanoi, Vietnam

  Sexually Transmitted Infections · 2025-02-10 · 3 citations

  articleOpen accessSenior author

  Background Mycoplasma genitalium (MG) is a critical pathogen of sexually transmitted infections (STIs) in men, associated with high antibiotic resistance. Understanding the clinical characteristics of MG infections can improve testing and treatment guidelines. Aims To investigate the clinical features and characteristics of asymptomatic, acute and chronic MG infections in heterosexual males. Methods From January 2018 to September 2023, men diagnosed with urethral STIs using multiplex real-time PCR were enrolled into this cross-sectional study. Testing indications included males with urethritis, suspected STIs and asymptomatic screening. Based on clinical symptoms, participants were classified as acute, chronic or asymptomatic groups. An electronic-based survey was administered to assess demographic, behavioural and clinical information. Univariate and multivariate logistic regression were performed to assess for factors associated with the presence of symptoms. Result Among the 2102 men who have sex with women and were tested for STI, 879 records met the eligibility criteria for further analysis; MG was detected in 14.6% of the 2102 cases. Most patients presented with acute urethral symptoms (75.6%). Among men infected with MG, mono-infection accounted for 52.8%, while Chlamydia trachomatis and Neisseria gonorrhoeae co-infections occurred in 39.3% and 21.3%, respectively. Co-infections were more prevalent among acute urethritis compared with chronic urethritis or asymptomatic groups. Multivariable analysis revealed associations between chronic symptoms with absence of urethral discharge (aOR 0.31; 95% CI 0.2 to 0.47), previous antibiotic use (aOR 6.83; 95% CI 4.47 to 10.4), marriage (aOR 1.66; 95% CI 1.09 to 2.51) and history of STIs (aOR 2.08; 95% CI 1.24 to 3.49). Conclusion Our study revealed a 14.6% prevalence of MG among individuals tested for STIs. Most patients presented with acute urethral symptoms, while chronic symptoms were associated with marriage, antibiotic use history and previous STIs. Routine MG screening of asymptomatic patients is not recommended, but improved access to diagnostics and further research is needed for clinical practice in low-resource settings.

  PublisherOA PDFDOI

• Doxycycline prophylaxis for bacterial sexually transmitted infection prevention in Vietnam: awareness, attitudes and willingness to use among men who have sex with men using HIV-PrEP

  Sexually Transmitted Infections · 2025-02-06 · 2 citations

  articleOpen access

  OBJECTIVES: Doxycycline prophylaxis shows promise for bacterial sexually transmitted infection (STI) prevention, but data primarily come from high-income countries. This study assessed awareness, willingness and factors associated with willingness to use doxycycline for bacterial STI prevention among men who have sex with men (MSM) using HIV pre-exposure prophylaxis (HIV-PrEP) in Vietnam. METHODS: Between 25 January and 4 February 2024, a cross-sectional study recruited males aged ≥18 years who reported having sex with men in the past 12 months from 11 HIV-PrEP clinics in Hanoi and Ho Chi Minh City. Self-administered surveys were conducted, and multivariable logistic regression was applied to identify factors associated with willingness to use doxycycline prophylaxis. RESULTS: Among 350 participants, the median age was 25 (IQR 21-30), and 10.6% self-reported a bacterial STI diagnosis in the past 12 months. In the previous 6 months, the median number of sex partners was 2 (IQR 1-4), 53.1% reported condomless anal sex. Awareness of doxycycline was low (20.2%; 65/322); however, 75.4% (264/350) expressed willingness to use it, with 63.6% (168/264) preferring doxyPrEP. Participants who disclosed HIV-PrEP use to all sex partners (adjusted OR (aOR) 4.17; 95% CI 1.84, 9.46) and those with higher perceived STI risk (aOR 1.12; 95% CI 1.03, 1.22) were more likely to report willingness to use doxycycline prophylaxis. Concerns about daily medication (aOR 0.43; 95% CI 0.24, 0.81) and fear of judgement from peers (aOR 0.41; 95% CI 0.21, 0.81) were associated with lower willingness. CONCLUSIONS: Knowledge of doxycycline prophylaxis among MSM on HIV-PrEP in Vietnam was low. However, most expressed willingness to use it, with two-thirds preferring doxyPrEP. Findings highlight the need to disseminate information on doxycycline prophylaxis for bacterial STI prevention, monitoring the usage and evaluating comparative effectiveness of doxyPEP and doxyPrEP to guide implementation efforts in Vietnam.

  PublisherOA PDFDOI

• Variability of antimicrobial susceptibility of commensal Neisseria species supports its use as a marker of excessive antimicrobial consumption – reflections from the results of a four-country study

  International Journal of Infectious Diseases · 2025-03-07 · 2 citations

  articleOpen access

  This perspective explores the utility of commensal Neisseria species as an early warning sign of excessive antimicrobial consumption. Little is known as to how the prevalence and antimicrobial susceptibility of various commensal Neisseria species varies between populations around the world. We compared the prevalence and antimicrobial susceptibilities of oral commensal Neisseria species in the general population and cohorts of men who have sex with men (MSM) in four countries with available data - Belgium, Italy, Japan and Vietnam. In individuals where Neisseria spp. were detected, N. subflava was present in 70-100% of individuals in the different studies. The N. subflava azithromycin and ciprofloxacin minimum inhibitory concentrations (MICs) were higher in the MSM than in the general population. The MICs of all Neisseria spp. were very similar in the general populations of Belgium and Italy. For all Neisseria spp., azithromycin and ceftriaxone MICs were higher, whereas ciprofloxacin MICs were lower in Belgium and Italy than in Japan. The higher azithromycin and ciprofloxacin MICs observed in the cohorts of MSM compared to the general population and the higher ciprofloxacin MICs in Japan compared to Belgium and Italy are commensurate with the most commonly antimicrobial prescribed in these populations. Our results support using commensal Neisseria species as an early warning system of excessive antimicrobial consumption.

  PublisherOA PDFDOI

• Routine testing for chlamydia and gonorrhea in an HIV preexposure prophylaxis program in Hanoi, Vietnam: implications for low- and middle-income countries

  AIDS · 2025-04-03 · 2 citations

  article1st authorCorresponding

  OBJECTIVES: To assess the prevalence, anatomical distribution, and correlates of Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections within an HIV preexposure prophylaxis (PrEP) program in Hanoi, Vietnam. DESIGN: Cross-sectional, observational study. METHODS: Between January and December 2022, HIV PrEP program clients who were male at birth, ≥16 years old, reported ≥1 male sex partner in the prior 12 months, were enrolled. A questionnaire collected sociodemographics, sexual behaviors, and clinical data. CT/NG testing was performed on self-collected urine, rectal, and pharyngeal specimens. Multivariate logistic regression was used to identify factors associated with infections. RESULTS: Among 529 participants, the prevalence of CT or NG was 28.9% (153/529). The prevalence of NG was 14.4% (76/529) and highest for pharyngeal infections (11.7%; 62/528), while for CT, the prevalence was 20.4% (108/529) and highest for rectal infections (15.0%; 74/493). Symptoms in the prior week were reported by 45.8% (70/153) of those with CT or NG infections. Among asymptomatic participants, there was a low prevalence of urethral CT (3.1%; 14/457) and NG (0.9%; 4/457). Condomless anal sex [adjusted odds ratio (aOR) = 1.98; 95% confidence interval (CI): 1.27, 3.09] and sexualized drug use in the prior 6 months (aOR = 1.71; 95% CI: 1.09, 2.69) were associated with CT/NG infections. CONCLUSIONS: The study found a high prevalence of CT/NG infections, particularly pharyngeal and rectal infections, within an HIV PrEP program in Hanoi, Vietnam. The findings suggest testing for urethral infections among asymptomatic individuals is of limited value. Further research is needed for STI prevention strategies and updated guidelines for CT/NG screening in HIV PrEP programs in low- and middle-income countries.

  PublisherDOI

• High Prevalence of Ceftriaxone-Resistant <i>Neisseria gonorrhoeae</i> in Hanoi, Vietnam, 2023–2024

  The Journal of Infectious Diseases · 2025-02-10 · 23 citations

  articleOpen accessSenior author

  Ceftriaxone resistance in Neisseria gonorrhoeae is an escalating global health concern, threatening the efficacy of empiric treatment. In the Asia-Pacific region, a rapid surge in ceftriaxone resistance has been observed, primarily associated with the penA-60.001 allele. This study, conducted in Hanoi, Vietnam between 2023 and 2024, analyzed 352 N. gonorrhoeae isolates and found a 27% prevalence of ceftriaxone resistance. Whole-genome sequencing identified that resistance was predominantly driven by the mosaic penA-237.001 allele, with a smaller contribution from penA-60.001. The high prevalence of resistance and the emergence of new alleles underscore the urgent threat to ceftriaxone as an empiric treatment option.

  PublisherDOI

• Impact of changing pre‐exposure prophylaxis regimens on retention among men who have sex with men in Hanoi, Vietnam (2020−2023): a cohort study

  Journal of the International AIDS Society · 2025-07-01 · 1 citations

  articleOpen access

  INTRODUCTION: We examined the association of pre-exposure prophylaxis (PrEP) programme retention with the use of daily, event-driven (ED) or regimen switching reported during follow-up at any point prior to discontinuation among men who have sex with men (MSM) in Hanoi, Vietnam. METHODS: Between April 2020 and February 2023, we collected data from PrEP clients at Hanoi Medical University Sexual Health Promotion clinic who were prescribed either ED or daily PrEP at the initial visit; at subsequent visits, clients reported the regimen used since the prior visit. We defined three categories of PrEP use: ED-PrEP exclusively, daily PrEP exclusively and switching regimens. The primary outcome was time to discontinuation in the PrEP programme during the study period, defined as missing a scheduled visit by > 30 days. We performed survival analysis using Kaplan-Meier curves. RESULTS: In total, 2107 people were included: 61.1% (n = 1288) reported exclusive use of daily PrEP, 10.4% (n = 220) reported exclusive use of ED-PrEP and 28.4% (n = 599) reported switching PrEP regimens. Among switchers, 29.40% (n = 176) switched more than once. Furthermore, 82.5% switched from daily to ED-PrEP and 17.5% switched from ED to daily PrEP. The median time to discontinuation in the PrEP programme was 105 days (IQR: 52-182) among those reporting exclusive use of ED-PrEP, 104 days (IQR: 56-274) among those reporting exclusive use of daily PrEP and 163 days (IQR: 101-308) among those who switched. Among switchers, those who switched more than once had a median time to discontinuation in the PrEP programme of 231 days (IQR: 137-380) in comparison to 133 days (IQR: 90-274) for those who switched once. CONCLUSIONS: We provide real-world data from MSM in an HIV PrEP programme in Vietnam that those who switched had longer periods of retention during the study period. Our findings suggest that offering flexible PrEP regimen options may improve engagement and long-term adherence among this population.

  PublisherOA PDFDOI

• Field evaluation of a dual treponemal/non-treponemal point-of-care test for syphilis within an HIV pre-exposure prophylaxis programme in Hanoi, Vietnam

  Sexually Transmitted Infections · 2025-10-17

  articleOpen accessSenior authorCorresponding

  OBJECTIVES: Syphilis infections are high among men who have sex with men (MSM) on HIV pre-exposure prophylaxis (PrEP). Point-of-care (POC) testing may improve diagnosis and treatment. We performed a field evaluation of the Chembio dual path platform (DPP) Syphilis Screen and Confirm treponemal/non-treponemal POC test within an HIV PrEP programme in Hanoi, Vietnam. METHODS: From December 2023 to July 2024, males aged ≥16 years enrolled in the HIV PrEP programme who reported sex with men in the last year were enrolled. Specimens were tested using the Chembio DPP syphilis screen and confirm test and reference treponemal (Abbott Bioline or Determine) and non-treponemal (rapid plasma reagin (RPR)) tests. Positive per cent agreement (PPA), negative per cent agreement (NPA), positive predictive value (PPV), negative predictive value (NPV) and Cohen's kappa were calculated comparing the DPP versus reference tests. RESULTS: We enrolled 400 participants; median age was 26.4 years (IQR 22.5-30.4); one invalid test was excluded. The prevalence of a reactive treponemal test was 35.3% (141/399). For the DPP treponemal test, PPA was 75.2% (95% CI 67.2% to 82.2%), NPA was 96.9% (95% CI 94% to 98.7%), PPV was 93% (95% CI 86.8% to 96.4%), NPV was 87.7% (95% CI 83.4% to 91%), and Cohen's kappa was 0.75. For the DPP non-treponemal test, PPA was 36.5% (95% CI 23.6% to 51%), NPA was 99.4% (95% CI 97.9% to 99.9%), PPV was 90.5% (95% CI 71.1% to 97.4%), NPV was 91.3% (95% CI 88% to 93.7%), and Cohen's kappa was 0.48 (95% CI 0.33 to 0.61). For RPR titres ≥1:8, PPA and Cohen's kappa increased to 85.7% (95% CI 57.2% to 98.2%) and 0.67 (95% CI 0.47 to 0.81), respectively. CONCLUSIONS: Among MSM in an HIV PrEP programme with high syphilis prevalence, the DPP treponemal test performed well. While non-treponemal performance was lower, it was strong for RPR titres ≥1:8, suggesting it could aid in identifying high-titre syphilis infections more likely to be transmissible.

  PublisherOA PDFDOI

• 2647 Battle score for risk stratification in a regional trauma unit – A service evaluation

  2024-09-30

  article1st authorCorresponding

  <h3>Aims and Objectives</h3> Introduction: Chest injuries account for a high proportion of hospital admissions and delayed mortality in trauma patients. The Battle Score was derived in a UK Major Trauma Centre, externally validated in 7 UK hospitals and has been widely adopted as a risk stratification and prognostication tool for chest trauma. However validation studies among the older, frailer cohort of trauma patients who tend to be managed in Trauma Units are limited. Aims: To describe the demographics of patients admitted with chest injuries at a regional Trauma Unit in Southeast Scotland and compare complication and mortality rates with the original Battle cohort. <h3>Method and Design</h3> Retrospective analysis of discharge summaries of 131 patients admitted with chest trauma at the Victoria Hospital, NHS Fife between 2022 and 2023. <h3>Results and Conclusion</h3> Results: Median [IQR] age in the NHS Fife cohort was 76 [25] compared with 69 [28] and 57 [34] in the original derivation and validation cohorts respectively. Table 1 compares complication rates by Battle Score in the NHS Fife cohort and the original cohort. The most common complication across all Battle Scores was hospital stay ≥7 days which accounted for 48.1% of total complications. <h3>Discussion</h3> In patients with chest trauma presenting to our regional Trauma Unit the complication rate at lower Battle Scores is substantially higher than that originally reported by Battle, while the complication rate at higher Battle Scores is very similar. The population in our study is substantially older than both the derivation and validation cohorts. Complication rates in our cohort are largely driven by hospital length of stay, which may relate more to pre-existing frailty and increased care requirements after trauma. Battle Score should therefore be used with caution as a prognostic tool in our patient population, particularly at lower scores which may significantly underestimate the likelihood of prolonged hospital admission.

  PublisherDOI

• Erratum: Absence of Lymphogranuloma Venereum Among Men Who Have Sex With Men With Rectal Chlamydia trachomatis Infections Within an HIV Preexposure Prophylaxis Program in Hanoi, Vietnam

  Sexually Transmitted Diseases · 2024-12-31

  erratumSenior author
  PublisherDOI

• Tỷ lệ nhiễm Chlamydia trachomatis và Neisseria gonorrhoeae ở nam quan hệ tình dục đồng giới sử dụng liệu pháp dự phòng trước phơi nhiễm HIV tại phòng khám Sống Hạnh phúc bệnh viện Đại học Y Hà Nội năm 2022

  Tạp chí Y học Dự phòng · 2024-12-30

  article

  Nghiên cứu xác định tỷ lệ, phân bố nhiễm Chlamydia trachomatis (Ct) và/hoặc Neisseria gonorrhoeae (Ng) ở khách hàng nam sử dụng liệu pháp dự phòng trước phơi nhiễm HIV (PrEP) theo vị trí xét nghiệm và triệu chứng được báo cáo. Khách hàng PrEP tại phòng khám SHP năm 2022 được xét nghiệm Ct/Ng tại hầu họng, hậu môn, nước tiểu và tự trả lời bộ câu hỏi trực tuyến. Xét nghiệm thực hiện tại bệnh viện Bạch Mai. Nghiên cứu có 529 người tham gia là nam có quan hệ tình dục với người nam khác (MSM) trong 12 tháng qua, tuổi trung vị 25,1 (IQR: 21,7– 29,7). Tỷ lệ dương tính với Ct là 20,5%; Ng là 14,6%; Ct/Ng là 29,3%. Tỷ lệ nhiễm Ct/Ng tại niệu đạo là 6,4%, 18,0% tại trực tràng và 15,7% tại hầu họng. Hơn ½ (56,1%) trong số những người có kết quả dương tính với Ct/Ng (n = 155) không triệu chứng trong 7 ngày qua. Với người có triệu chứng, dương tính với Ct/Ng là 4,0% tại niệu đạo, 7,6% tại trực tràng, 12,9% tại hầu họng. Với người không triệu chứng, dương tính Ct/Ng là 2,5%, 10,4% và 7,8% tại niệu đạo, trực tràng và hầu họng. Tỷ lệ nhiễm Ct và/hoặc Ng ở MSM sử dụng PrEP tại Hà Nội cao. Hơn ½ ca nhiễm trùng xảy ra ở người không có triệu chứng, và tỷ lệ dương tính ở những người có triệu chứng cao hơn.

  PublisherDOI

Recent grants

• Antimicrobial resistance in Neisseria gonorrhoeae among men on PrEP in Vietnam

  NIH · $958k · 2021–2026

Frequent coauthors

• Jeffrey D. Klausner

  University of Southern California

  35 shared

• Eric Y. Lin

  University of California, Los Angeles

  15 shared

• Sung Min Ha

  University of California, Los Angeles

  13 shared

• Purnima Madhivanan

  11 shared

• Lê Minh Giang

  Hanoi Medical University

  10 shared

• Kate Button

  Cardiff University

  9 shared

• Jeffrey Klaunser

  University of California, Los Angeles

  9 shared

• Karl Krupp

  University of Arizona

  7 shared

Education

• MD, School of Medicine

  University of California San Francisco

  2015

• MPH, Epidemiology and Biostatistics

  University of California Berkeley School of Public Health

  2009

• BA, Molecular and Cell Biology

  University of California Berkeley

  2007

Awards & honors

• Infectious Disease, American Board of Internal Medicine, 202…
• Internal Medicine, American Board of Internal Medicine, 2018