Outer membrane vesicles generated by an exogenous bacteriophage lysin and protection against Acinetobacter baumannii infection.

BACKGROUND: The outer membrane vesicles (OMVs) produced by Gram-negative bacteria can modulate the immune system and have great potentials for bacterial vaccine development. RESULTS: A highly active Acinetobacter baumannii phage lysin, LysP53, can stimulate the production of OMVs after interacting with A. baumannii, Escherichia coli, and Salmonella. The OMVs prepared by the lysin (LOMVs) from A. baumannii showed better homogeneity, higher protein yield, lower endotoxin content, and lower cytotoxicity compared to the naturally produced OMVs (nOMVs). The LOMVs contain a significantly higher number of cytoplasmic and cytoplasmic membrane proteins but a smaller number of periplasmic and extracellular proteins compared to nOMVs. Intramuscular immunization with either LOMVs or nOMVs three times provided robust protection against A. baumannii infections in both pneumonia and bacteremia mouse models. Intranasal immunization offered good protection in the pneumonia model but weaker protection (20-40%) in the bacteremia model. However, with a single immunization, LOMVs demonstrated better protection than the nOMVs in the pneumonia mouse model. CONCLUSIONS: The novel lysin approach provides a superior choice compared to current methods for OMV production, especially for vaccine development.

The serodiagnositic value of Chlamydia trachomatis antigens in antibody detection using luciferase immunosorbent assay.

Introduction: Among the different antigens used in the detection of anti-Chlamydia trachomatis antibodies, significant differences in sensitivity and specificity have been observed. Further evaluation of C. trachomatis antigens in antibody detection is urgently needed for the development and application of C. trachomatis serologic assays. Methods: Chlamydia trachomatis antigens Pgp3, TmeA, InaC, and HSP60 were selected and used in luciferase immunosorbent assay (LISA). The detection results obtained from well-defined C. trachomatis positive and negative samples were compared with the commercial C. trachomatis ELISA (Mikrogen) for performance evaluation. Results: Pgp3, TmeA, InaC, and HSP60-based LISA showed sensitivity of 92.8, 88.8, 90.4, and 94.4%, and specificity of 99.2, 99.2, 99.2, and 92%, respectively. ROC analysis indicated that Pgp3-based LISA showed similar performance to Mikrogen ELISA (AUC 0.986 vs. 0.993, p = 0.207). Furthermore, four C. trachomatis antigens achieved strong diagnostic efficiency, i.e., positive likelihood ratios [+LR] ≥ 10 in C. trachomatis-infected women and negative likelihood ratios [-LR] ≤ 0.1 in C. trachomatis negative low exposure risk children, but only Pgp3 and TmeA showed strong diagnostic value in general adults. In addition, Pgp3, TmeA, and InaC, but not HSP60, achieved high performance, i.e., both positive predictive value (PPV) and negative predictive value (NPV) ≥ 90.9%, and showed no significant cross-reactivity with anti-Chlamydiapneumoniae. Conclusion: Three C. trachomatis species-specific antigens Pgp3, TmeA, and InaC show superior performance in the detection of anti-C. trachomatis antibody, indicating the potential to be used in developing C. trachomatis serologic tests.

Butorphanol inhibits androgen biosynthesis and metabolism in rat immature Leydig cells in vitro.

Butorphanol is a synthetic opioid analgesic medication that is primarily used for the management of pain. Butorphanol may have an inhibitory effect on androgen biosynthesis and metabolism in rat immature Leydig cells. The objective of this study was to investigate the influence of butorphanol on androgen secretion by rat Leydig cells isolated from the 35-day-old male rats. Rat Leydig cells were cultured with 0.5-50 µM butorphanol for 3 h in vitro. Butorphanol at 5 and 50 µM significantly inhibited androgen secretion in immature Leydig cells. At 50 µM, butorphanol also blocked the effects of luteinizing hormone (LH) and 8bromo-cAMP-stimulated androgen secretion and 22R-hydroxycholesterol- and pregnenolone-mediated androgen production. Further analysis of the results showed that butorphanol downregulated the expression of genes involved in androgen production, including Lhcgr (LH receptor), Cyp11a1 (cholesterol side-chain cleavage enzyme), Srd5a1 (5α-reductase 1), and Akr1c14 (3α-hydroxysteroid dehydrogenase). Additionally, butorphanol directly inhibited HSD3B1 (3ß-hydroxysteroid dehydrogenase 1) and SRD5A1 activity. In conclusion, butorphanol may have side effects of inhibiting androgen biosynthesis and metabolism in Leydig cells.

LysP53 activity against Salmonella and its application in decontamination of Salmonella on fresh romaine lettuce.

Salmonella is a zoonotic pathogen that is commonly associated with foodborne disease outbreaks. This study found that a newly identified Gram-negative lysin LysP53 had good activity against a wide range of Salmonella, including Salmonella Newington, Salmonella Typhimurium, and Salmonella Dublin. Without the help of an outer membrane permeabilizer, 4 µM LysP53 could reduce 97.6% of planktonic Salmonella Enteritidis and 90% of the bacteria in biofilms. Moreover, LysP53 was highly thermostable because it maintained >90% activity even after exposure to temperatures up to 95 °C. Although high concentrations of salts could reduce the activity, LysP53 was found safe for oral gavage of mice without affecting body weights and cytokines in sera and able to reduce 90% of Salmonella Enteritidis loads on fresh romaine lettuce after 30 min of treatment. Because of its good activity against a wide range of bacteria, thermal stability, safe for oral administration, LysP53 could be used as a biocontrol agent for reducing bacterial loads in fresh vegetable food. KEY POINTS: • Lysin LysP53 has high bactericidal activity against Salmonella. • LysP53 is thermostable even at high temperature of up to 95 °C. • LysP53 can be used for topical decontamination of Salmonella on vegetables.

Validity of patients' online reviews at direct-to-consumer teleconsultation platforms: a protocol for a cross-sectional study using unannounced standardised patients.

INTRODUCTION: As direct-to-consumer teleconsultation (hereafter referred to as 'teleconsultation') has gained popularity, an increasing number of patients have been leaving online reviews of their teleconsultation experiences. These reviews can help guide patients in identifying doctors for teleconsultation. However, few studies have examined the validity of online reviews in assessing the quality of teleconsultation against a gold standard. Therefore, we aim to use unannounced standardised patients (USPs) to validate online reviews in assessing both the technical and patient-centred quality of teleconsultations. We hypothesise that online review results will be more consistent with the patient-centred quality, rather than the technical quality, as assessed by the USPs. METHODS AND ANALYSIS: In this cross-sectional study, USPs representing 11 common primary care conditions will randomly visit 253 physicians via the three largest teleconsultation platforms in China. Each physician will receive a text-based and a voice/video-based USP visit, resulting in a total of 506 USP visits. The USP will complete a quality checklist to assess the proportion of clinical practice guideline-recommended items during teleconsultation. After each visit, the USP will also complete the Patient Perception of Patient-Centeredness Rating. The USP-assessed results will be compared with online review results using the intraclass correlation coefficient (ICC). If ICC >0.4 (p<0.05), we will assume reasonable concordance between the USP-assessed quality and online reviews. Furthermore, we will use correlation analysis, Lin's Coordinated Correlation Coefficient and Kappa as supplementary analyses. ETHICS AND DISSEMINATION: This study has received approval from the Institutional Review Board of Southern Medical University (#Southern Medical Audit (2022) No. 013). Results will be actively disseminated through print and social media, and USP tools will be made available for other researchers. TRIAL REGISTRATION: The study has been registered at the China Clinical Trials Registry (ChiCTR2200062975).

Effectiveness of chlamydia Test and Treat strategy in preventing adverse pregnancy outcomes: protocol for a randomized controlled trial.

Introduction: Chlamydia trachomatis is one of the most common bacterial sexually transmitted infections worldwide, and is associated with an increased risk of adverse pregnancy outcomes. However, whether providing chlamydia screening and treatment during the first trimester of pregnancy could reduce adverse pregnancy outcomes is still not clear. This study reports a randomized controlled trial (RCT) protocol to evaluate the effectiveness of chlamydia Test and Treat during early pregnancy in preventing adverse pregnancy outcomes in China. Methods and analysis: This trial is a multi-center two-arm RCT targeting 7,500 pregnant women in early pregnancy (6-20 weeks). The inclusion criteria included: 18-39 years old, on their first antenatal visit, in the first trimester, and plan to deliver in the study cities. Following a block randomization procedure, every block of twenty women will be randomly assigned in a 1:1 ratio into two arms: (1) a Test and Treat arm in which women receive free chlamydia testing immediately after enrollment and people tested as chlamydia positive will receive standardized treatment and partner treatment; (2) a control arm in which women receive regular prenatal care without receiving testing during the pregnancy period, but collect urine samples and test them after delivery or indicating a chlamydia-related complication during pregnancy happens. The primary outcome is a composite of eight adverse events rate at delivery between two arms, including stillbirth, infant death, spontaneous abortion, preterm labor, low birth weight, premature rupture of membranes, postpartum endometritis, and ectopic pregnancy. Secondary outcomes include the cost-effectiveness of the intervention, the proportion of people tested with chlamydia infection, the proportion of tested-positive patients that received treatment, and the proportion of people who were cured 1 month after the treatment initiation. Urine specimens will be collected and tested for chlamydia by using Nucleic Acid Amplification Test. Data will be analyzed according to the intention-to-treat principle. Discussion: This trial will test the hypothesis that early testing and treating of chlamydia can reduce the risk for adverse pregnancy outcomes and may help in developing chlamydia screening guidelines in China and other countries with a similar prevalence of chlamydia infection. Trial registration: Chinese Clinical Trials Registry, ChiCTR2000031549. Registered on April 4, 2020.

Synthesis of 3,4,5-trisubstituted phenols via Rh(III)-catalyzed alkenyl C-H activation assisted by phosphonium cations.

An efficient method for the construction of various 3,4,5-trisubstituted phenol derivatives has been achieved via the Rh(III)-catalyzed coupling of phosphonium cations with internal alkynes. This protocol shows good substrate compatibility, as an array of structurally and electronically diverse phosphonium compounds react efficiently with up to 87% yield.

Rh(III)-catalyzed [4 + 1] cyclization of aryl substituted pyrazoles with cyclopropanols via C-H activation.

A rhodium-catalyzed formal [4 + 1]-cyclization reaction of aryl substituted pyrazoles with cyclopropanols via C-H bond activation/cyclization processes to selectively construct a series of carbonyl functionalized pyrazolo[5,1-a]isoindoles is described. The reaction features good functional group compatibility and a broad substrate scope with respect to both cyclization components with up to 84% yields. Mechanistic studies indicated that the C-H cleavage might be the rate-determining step in this transformation.

A Molecular Engineering Strategy for Achieving Blue Phosphorescent Carbon Dots with Outstanding Efficiency above 50.

Highly efficient emission has been a long-lasting pursuit for carbon dots (CDs) owing to their enormous potential in optoelectronic applications. Nevertheless, their room-temperature phosphorescence (RTP) performance still largely lags behind their outstanding fluorescence emission, especially in the blue spectral region. Herein, high-efficiency blue RTP CDs have been designed and constructed via a simple molecular engineering strategy, enabling CDs with an unprecedented phosphorescence quantum efficiency of to 50.17% and a long lifetime of 2.03 s. This treating route facilitates the formation of high-density (n, π*) configurations in the CD π-π conjugate system through the introduction of abundant functional groups, which can evoke a strong spin-orbit coupling and further promote the intersystem crossing from singlet to triplet excited states and radiative recombination from triplet excited states to ground state. With blue phosphorescent CDs as triplet donors, green, red, and white afterglow composites are successfully fabricated via effective phosphorescence Förster resonance energy transfer. Importantly, the color temperature of the white afterglow emission can be widely and facilely tuned from cool white to pure white and warm white. Moreover, advanced information encryption, light illumination, and afterglow/dynamic visual display have been demonstrated when using these multicolor-emitting CD-based afterglow systems.

Carbon Dots Mediated In Situ Confined Growth of Bi Clusters on g-C3 N4 Nanomeshes for Boosting Plasma-Assisted Photoreduction of CO2.

Synthesis of high-efficiency, cost-effective, and stable photocatalysts has long been a priority for sustainable photocatalytic CO2 reduction reactions (CRR), given its importance in achieving carbon neutrality goals under the new development philosophy. Fundamentally, the sluggish interface charge transportation and poor selectivity of products remain a challenge in the CRR progress. Herein, this work unveils a synergistic effect between high-density monodispersed Bi/carbon dots (CDs) and ultrathin graphite phase carbon nitride (g-C3 N4 ) nanomeshes for plasma-assisted photocatalytic CRR. The optimal g-C3 N4 /Bi/CDs heterojunction displays a high selectivity of 98% for CO production with a yield up to 22.7 µmol g-1 without any sacrificial agent. The in situ confined growth of plasmonic Bi clusters favors the production of more hot carriers and improves the conductivity of g-C3 N4 . Meanwhile, a built-in electric field driving force modulates the directional injection photogenerated holes from plasmonic Bi clusters and g-C3 N4 photosensitive units to adjacent CDs reservoirs, thus promoting the rapid separation and oriented transfer in the CRR process. This work sheds light on the mechanism of plasma-assisted photocatalytic CRR and provides a pathway for designing highly efficient plasma-involved photocatalysts.

Thermosensitive Hydrogel Wound Dressing Loaded with Bacteriophage Lysin LysP53.

Wound infections are prone to attacks from infectious pathogens, including multidrug resistant bacteria that render conventional antimicrobials ineffective. Recently, lysins have been proposed as alternatives to conventional antimicrobials to tackle the menace of multidrug resistance pathogens. The coupling of lysins with a material that will cover the wound may prove beneficial in both protecting and treating wound infections. Hence, in this study, a Gram-negative lysin, LysP53, was coupled with a thermosensitive hydrogel, poloxamer P407, and its efficacy to treat wound infection was tested. In vitro, the addition of LysP53 to the poloxamer did not affect its thermosensitive characteristics, nor did it affect the hydrogel structure. Moreover, the lysin hydrogel could hydrolyze the peptidoglycan, demonstrating that it may have bactericidal activity. Up to 10.4% of LysP53 was released from the hydrogel gradually within 24 h, which led to a 4-log reduction of stationary phase Acinetobacter baumannii. Lastly, the lysin hydrogel was found safe with no cytotoxic effects observed in cells. Ex vivo, LysP53 hydrogel could inhibit bacterial growth on a pig skin decolonization model, with 3-log differences compared to non-treated groups. Overall, our results suggest that lysin-loaded hydrogels may provide a novel solution to treat wound infections caused by resistant bacteria.

Chlamydia infection, PID, and infertility: further evidence from a case-control study in China.

BACKGROUND: Chlamydia trachomatis infection and pelvic inflammatory disease (PID) are well-known risk factors for female infertility. But there is limited evidence from China. This study aimed to further explore the associations between previous/current chlamydial infection, PID, and infertility in China. METHODS: We performed a 1:2 matched case-control study with two control groups: pregnant controls and non-pregnant controls in China in 2019. Women diagnosed with infertility were selected as cases (n = 255). Controls were selected based on the following criteria: Pregnant women who were documented in the selected hospitals were chosen as Pregnant controls (n = 510), and people who sought health care in Obstetric/Gynecologic clinics, Family Planning clinics, Dermatology and STD Department or Urological department were selected as Non-pregnant controls (n = 510). Infertility induced by male factors and people who used antibiotics in the vagina within two weeks were excluded. The first-stream specimen of urine samples was tested for chlamydia by nucleic acid amplification testing (NAAT). Conditional logistic regression was used to estimate the association. RESULTS: The prevalence of previous chlamydial infection and PID were significantly higher in cases (2.4%, 17.3%) than in controls (Non-pregnancy: 0.4%, 3.0%; Pregnancy: 0.4%, 9.0%). The current chlamydial infection rates were 5.9%, 7.3%, and 7.1% in infertile, pregnant, and non-pregnant women, respectively. After adjusting for confounders, PID largely elevated the risk of infertility (using non-pregnant controls: adjusted OR = 2.57, 95% CI 1.51, 4.39; using pregnant controls: adjusted OR = 6.83, 95% CI 3.47, 13.43). And the positive association between PID and tubal infertility was more obvious for both groups. For current chlamydial infection, none of the odds ratios were significant at the 0.05 level, while small sample size limited the evaluation of an association between prior chlamydial infection with infertility. CONCLUSIONS: Previous PID was indicated to largely increase the risk of infertility, especially tubal infertility. And there should be continuing emphasis on highly sensitive and specific biomarker for prior chlamydial infection.

Online sex-seeking among Chinese heterosexual men who seek care in sexually transmitted infections clinics: a cross-sectional study.

BACKGROUND: The Internet has become an important virtual venue for men who have sex with men to seek sexual partners, with a high potential threat to spread sexually transmitted infections (STIs). However, the online sex-seeking use and its risk causing STIs spread remain unclear among heterosexual men. We conducted a cross-sectional study to investigate the use of online sex-seeking venues and the related risky sex activities (e.g. condomless sex, quick sex) in STIs clinics in Guangdong, China. METHODS: These STIs clinics were involved in the Guangdong governmental sentinel network and we recruited heterosexual men (age > = 18) between March and August 2018. Multivariable logistic regression models were used to identify the factors associated with online sex-seeking use and risky sex activities with online sex partners. RESULTS: 191 of 2,154 participants (8.9%) ever sought sex online. Among users,16.8% met their partners in-person within 24 h, 31.4% engaged in condomless sex with their last online partner. Online sex-seeking was positively associated with a) Ever been diagnosed with STIs (aOR = 3.0, 95%CI:2.0-4.6), and b) Had casual sex in the last three months (aOR = 3.3, 95%CI 2.4-4.6). Condomless sex with the last online partner was negatively associated with the correct answer of "Having only one partner can reduce the risk to infect HIV" (aOR = 0.3, 95%CI:0.1-0.8). CONCLUSION: In China, online sex-seeking and its related risky sexual activities are not rare among heterosexual men. Future prevention strategies to reduce STIs incidence should especially target heterosexual men engaging in online sex-seeking.

One-Step Reverse Transcription Droplet Digital PCR Protocols for SARS-CoV-2 Detection and Quantification.

Droplet digital polymerase chain reaction (ddPCR) is a third generation of PCR that was recently developed to overcome the limitation of direct quantification observed in real-time quantification PCR (qPCR). Recent studies have shown that ddPCR is more sensitive than the gold standard reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) in detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) samples. In combination with multiplexing, multiple RT-ddPCR assays can be developed to directly quantify different SARS-CoV-2 nucleic acid targets within a single sample, significantly saving on cost and time. Since ddPCR is tolerant to a number of inhibitors unlike qPCR, it can be used to detect and quantify samples from complex environments like wastewater. Here we present three one-step RT-ddPCR protocols on how to develop simplex (one target), duplex (two targets), and triplex probe mix (three targets) assays for SARS-CoV-2 detection and quantification. The assays can be used for diagnosis or other research-related SARS-CoV-2 applications.

Rhodium(III)-Catalyzed Sequential Cyclization of N-Boc Hydrazones with Propargylic Monofluoroalkynes via C-H Activation/C-F Cleavage for the Synthesis of Spiro[cyclobutane-1,9'-indeno[1,2-a]indenes].

An effective rhodium(III) catalysis for the construction of valuable tetracyclic compounds is described herein. This domino process involving the C-H activation/[3 + 2] annulation/intramolecular Friedel-Crafts reaction sequences of simple and readily available N-Boc hydrazones and propargylic monofluoroalkynes afforded fused tetracyclic spiro[cyclobutane-1,9'-indeno[1,2-a]indenes] in moderate to good yields, featuring three C-C bond formation. Moreover, control experiments indicated that the C-H activation might be involved in the rate-determining step.

Potential occupational exposure of parents to endocrine disrupting chemicals, adverse birth outcomes, and the modification effects of multi-vitamins supplement and infant sex.

BACKGROUND: Maternal occupational exposure to endocrine disrupting chemicals (EDCs) may have adverse effect on birth outcomes. However, little is known about paternal EDCs exposure and the combined effect of parental exposure on birth outcomes. OBJECTIVES: To assess the effects of both maternal and paternal occupational EDCs exposure on adverse birth outcomes, and further explore if multi-vitamins supplement and infant sex modify the association. METHODS: We conducted a prospective cohort study of 5421 mother-father-newborn groups in Guangzhou, China. A questionnaire informed by a job exposure matrix (JEM) was applied to collect parental occupational EDCs exposure based on the type of work performed. We used logistic regression to estimate association between parental EDCs exposure and birth outcomes (including preterm birth (PTB), low birth weight (LBW), birth defects and congenital heart defects (CHD)). Stratified analyses and Cochran Q tests were performed to assess the modifying effect of maternal multi-vitamins supplement use and infant sex. RESULTS: Compared with mothers unexposed, we found that mothers those exposed to EDCs were associated with increased odds of birth defects (aOR=1.70, 95% confidence interval (CI): 1.10-2.62), especially for those exposed for > 1.5 years (aOR= 3.00, 95% CIs: 1.78-5.03), or those with directly occupational exposed to EDCs (aOR= 2.94, 95% CIs: 1.72-5.04). Maternal exposure for > 1.5 years and direct exposure increased the risk of CHD, with aORs of 2.47 (1.21-5.02) and 2.79 (1.37-5.69), respectively. Stronger adverse effects were also observed when mothers and fathers were both exposed to EDCs. Paternal occupational EDCs exposure and exposure ≤ 1.5 years was associated with increased odds of LBW, with aORs of 2.14 (1.63-2.79) and 1.54 (1.10-2.15), respectively. When stratified by multi-vitamins supplement and infant sex, we observed slightly stronger effects for maternal exposure on birth defects/CHD as well as paternal EDCs exposure on PTB and LBW, among those without multi-vitamins supplement and among male babies, although the modification effects were not significant. CONCLUSION: Maternal exposure to EDCs was associated with greater odds of birth defects and CHD, while paternal exposure was mainly associated with greater odds of LBW. These effects tend to be stronger among mothers without multi-vitamins supplement and among male babies.

Intrinsic Antimicrobial Peptide Facilitates a New Broad-Spectrum Lysin LysP53 to Kill Acinetobacter baumannii In Vitro and in a Mouse Burn Infection Model.

Antimicrobial resistance-related infections of Gram-negative pathogens pose a huge threat to global public health. Lysins, peptidoglycan hydrolases from bacteriophages, are expected as an alternative weapon against drug-resistant bacteria. In the present study, we report a new lysin LysP53 from Acinetobacter baumannii phage 53. Bioinformatic analysis revealed that LysP53 contains a positively charged N-terminal region and a putative peptidase catalytic domain. In vitro biochemical experiments showed that LysP53 is active against multiple antibiotic-resistant Gram-negative bacteria, including A. baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, with a reduction of 5 logs in viable A. baumannii number after exposure to 100 µg/mL LysP53 for 1 h. Further studies showed that LysP53 contains a functional antimicrobial peptide, i.e., N-terminal 33 aa, with a comparable spectrum of activity to LysP53. In an A. baumannii-associated mouse model of burn infection, a single dose of 14 µg/mouse LysP53 (57.6 µM) showed higher decolonization efficacy than 4 µg/mouse minocycline- (874 µM; p < 0.05) and buffer-treated groups (p <0.001), leading to a bacterial reduction of 3 logs. Our findings collectively establish that LysP53 could be a promising candidate in the treatment of topical infections caused by multiple Gram-negative pathogens.

Prevalence of Chlamydia trachomatis Among Pregnant Women, Gynecology Clinic Attendees, and Subfertile Women in Guangdong, China: A Cross-sectional Survey.

BACKGROUND: Chlamydia trachomatis (CT) is a major cause of infertility and adverse birth outcomes, but its epidemiology among childbearing-age women remains unclear in China. This study investigated the prevalence of CT and associated factors among Chinese women aged 16-44 years who were either (1) pregnant, (2) attending gynecology clinics, or (3) subfertile. METHODS: We conducted a cross-sectional survey and recruited participants from obstetrics, gynecology, and infertility clinics in Guangdong between March and December 2019. We collected information on individuals' sociodemographic characteristics, previous medical conditions, and sexual behaviors. First-pass urine and cervical swabs were tested using nucleic acid amplification testing. We calculated the prevalence in each population and subgroup by age, education, and age at first sex. Multivariable binomial regression models were used to identify factors associated with CT. RESULTS: We recruited 881 pregnant women, 595 gynecology clinic attendees, and 254 subfertile women. The prevalence of CT was 6.7% (95% CI, 5.2%-8.5%), 8.2% (95% CI, 6.2%-10.7%), and 5.9% (95% CI, 3.5%-9.3%) for the above 3 populations, respectively. The subgroup-specific prevalence was highest among those who first had sex before age 25 years and older pregnant women (>35 years). The proportion of asymptomatic CT was 84.8%, 40.0%, and 60.0% among pregnant women, gynecology clinic attendees, and subfertile women, respectively. Age at first sex (<25 years), multipara, and ever having more than 1 partner increased the risk of CT. CONCLUSIONS: Childbearing-age women in China have a high prevalence of CT. As most women with CT were asymptomatic, more optimal prevention strategies are urgently needed in China.