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Applicability of TB-LAMP test for diagnosis of pulmonary TB among HIV-positive individuals
Get PDFThe loop-mediated isothermal amplification for TB (TB-LAMP) assay is more cost-effective and accessible than the Xpert® MTB/RIF assay. This study aimed to evaluate the diagnostic performance of the TB-LAMP assay in individuals with and without HIV infection. Patients aged ≥15 years presenting with symptoms of TB were included in the study. The TB-LAMP assay was performed alongside routine TB diagnostic methods, including the Xpert assay and smear microscopy, to evaluate discrepancies in test results and associated factors. A total of 903 patients were enrolled in the study. The positive percentage agreement for smear microscopy and TB-LAMP compared with the Xpert assay was respectively 54.3% (95% CI 46.6–61.8) and 76.6% (95% CI 69.9–82.6). Among HIV-positive individuals, the positive percentage agreement was 42.5% (95% CI 32.9–52.4) for smear microscopy and 68.9% (95% CI 59.1–77.5) for TB-LAMP. Factors such as age >60 years (adjusted OR 3.29, 95% CI 0.32–33.83), loss of appetite (aOR 0.30, 95% CI 0.13–0.70), and HIV-positive status (aOR 3.29, 95% CI 1.12–9.63) were associated with discrepancies between TB-LAMP and Xpert results. TB-LAMP demonstrated better agreement with the Xpert assay compared with smear microscopy in detecting TB among HIV-positive patients, suggesting that TB-LAMP could effectively replace smear microscopy.IJTLD Open, 2(1), pp.26-32; 2025journal articl
Progress and challenges in Nipah vaccine development and licensure for epidemic preparedness and response
Get PDFIntroduction: Nipah virus is a high-consequence pathogen that causes sporadic outbreaks with high mortality, and there are currently no vaccines or therapeutics available for Nipah. Vaccine development against Nipah faces challenges due to its current epidemiology with limited outbreak sizes, which impedes the feasibility of conducting vaccine efficacy trials focused on disease endpoints. Areas covered: We review the progress of Nipah vaccine candidates in human clinical trials and highlight the challenges in evaluating the vaccine efficacy due to the sporadic nature of Nipah outbreaks, given the epidemic potential of Nipah virus and its implications for pandemic preparedness. We examine the alternative regulatory pathways, including the US FDA’s Animal Rule and EMA’s conditional marketing authorization, which permit vaccine approval based on surrogate markers rather than efficacy data from the large-scale Phase-3 efficacy trials. The need for standardized immune surrogate markers is emphasized, alongside calls for international collaboration to develop such endpoints and manage stockpile strategies. Expert opinion: We recommend alignment among vaccine developers, regulators, and global health stakeholders to incentivize Nipah vaccine development and approval through alternative regulatory pathways, as well as ensuring epidemic preparedness via strategic vaccine stockpiling and response through targeted deployment strategies.Expert Review of Vaccines, 24(1), pp.183-193; 2025journal articl
Diagnostic accuracy of an antigen-based point-of-care test versus nucleic acid amplification testing for genital trichomoniasis among pregnant women attending antenatal care facilities in Zambia
Get PDFBackground: Infection with Trichomonas vaginalis (TV) is the most prevalent curable sexually transmitted infection (STI) globally and is associated with prelabour rupture of membranes, preterm delivery, and low birthweight. Pointof-care (POC) testing for TV during pregnancy may facilitate rapid antenatal case detection and treatment. This study, part of the World Health Organization’s global ProSPeRo study, aimed to evaluate the performance of OSOM® Trichomonas Rapid Test, an antigen-based POC test, against a reference nucleic acid amplifcation test (NAAT) among pregnant women in Zambia. We also assessed the operational characteristics and patient acceptability of the POC test, within the context of WHO’s target product profles for STI POC tests. Methods: We enrolled pregnant women attending four health centres in Nchelenge, Zambia, for antenatal care between 15 February and 26 May 2023. Vaginal swabs for the TV POC test and a reference NAAT (Aptima® Trichomonas vaginalis assay) were obtained. POC test results were read independently by two study staf members. Study staf flled a questionnaire on the operational characteristics of the POC test, and participants were asked about their willingness to wait for results. Results: Paired POC and reference test samples were collected from 1,015 participants. Overall, 23.0% (233/1015) tested positive for TV by NAAT, and 15.3% (155/1015) tested positive by the POC test, with three inconclusive results. The overall sensitivity and specifcity of the POC test were 66.4% (95% confdence intervals [CI] 57.7–74.1%) and 99.6% (95% CI: 98.8–99.9%), respectively. Sensitivity was higher among those with TV-associated symptoms compared to those without (83.6% versus 60.4%, relative ratio 1.39, 95% CI 1.14–1.68). Inter-rater agreement was 99.7% (Cohen’s Kappa 0.989). The study staf (n=14) found the test easy to use and interpret, with most staf (12/14) reporting results were available within 25 min. Conclusion: Overall, the TV POC test showed lower sensitivity than WHO’s 85% target, but exceeded the 99% specifcity target. Among symptomatic pregnant women, sensitivity nearly reached the WHO target. The assay was userfriendly, required minimal training, and delivered results quickly. Further studies are needed to determine the optimal antenatal settings for this technology.BMC Infectious Diseases, 24(Suppl 1), art. no. 1482; 2025journal articl
Pathological characterization of female reproductive organs prior to miscarriage induced by Zika virus infection in the pregnant common marmoset
Get PDFWhile Zika virus (ZIKV) infection in pregnant women is known to increase the risk of miscarriage and stillbirth, the mechanism by which ZIKV infection leads to the inability to continue a pregnancy is not clear. In our common marmoset models of ZIKV infection in pregnant individuals, miscarriage was observed in dams infected in the first or second trimester, and preterm delivery was observed in a dam infected in the third trimester. Serum progesterone levels were significantly lower prior to miscarriage or preterm delivery in the infected marmosets. To elucidate the pathology of the placental region just before the onset of ZIKV-induced miscarriage, we newly prepared an infected marmoset in the first trimester of pregnancy and euthanized it when the serum progesterone concentration was markedly reduced. Pathological analysis revealed significant degeneration in cells at the maternal-fetal interface, presumably trophoblasts. Cleaved-caspase was widely observed in the endometrial to placental region, and TNFα at 200 pg/mL was detected in the amniotic fluid, suggesting that apoptosis may progress in the endometrium and placenta, leading to decreased trophoblast function and miscarriage. ZIKV NS1 protein was found sporadically in the cellular degeneration area and widely in the basal layer of the endometrium. Furthermore, the viral protein was frequently detected in the follicles and corpus luteum of the ovary. The developed ZIKV infection model in pregnant marmosets would be useful not only to better understand the mechanism of ZIKV-induced miscarriage but also to analyze the effects of the viral infection on female reproductive tissues.Microbiology Spectrum, 13(4), art. no. e02282-24; 2025journal articl
異なる校種の接続の試み－スピーキング力育成への予備的考察－
Get PDFThe purpose of this preliminary study is to show that, under the current course of study, Japanese public junior high school and its prefectural high school students make no substantial and crucial progress with respect to structural complexity they create in speaking. The continuity of English learning between different schools in Japan, e.g. junior high and high schools, does not work properly for improvements in speaking ability. In order to improve the situation that the students are in, I will suggest that English education in Japanese junior high schools plays a key role.長崎大学教育開発推進機構紀要, 15, pp.31-37; 2025departmental bulletin pape
The potential of evaluating shape drawing using machine learning for predicting high autistic traits
Get PDFBackground: Children with high autistic traits often exhibit deficits in drawing, an important skill for social adaptability. Machine learning is a powerful technique for learning predictive models from movement data, so drawing processes and product characteristics can be objectively evaluated. This study aimed to assess the potential of evaluating shape drawing using machine learning to predict high autistic traits. Method: Seventy boys (5.03 ± 0.16) and 63 girls (5.06 ± 0.18) from the general population participated in the study. Participants were asked to draw shapes in the following order: equilateral triangle, inverted equilateral triangle, square, and the sun. A model for classifying participants as likely to have high autistic traits was developed using a support vector machine algorithm with a linear kernel utilizing 16 variables. A 16-inch liquid crystal display pen tablet was used to acquire data on hand-finger fine motor activity while the participants drew each shape. The X and Y coordinates of the pen tip, pen pressure, pen orientation, pen tilt, and eye movements were recorded to determine whether the participants had any problems with this skill. Eye movements were assessed using a webcam. These data and eye movements were used to identify the variables for the support vector machine model. Data and Results: For each shape, a model support vector machine was created to classify the high and low autistic trait groups, with accuracy, sensitivity, and specificity all above 85%. The specificity values across all models were 100%. In the inverted equilateral triangle model, specificity, accuracy, and sensitivity values were 100%. Conclusions: These results demonstrate the potential of assessing shape characteristics using machine learning to predict high levels of autistic traits. Future studies with a wider variety of shapes are warranted to establish further the potential efficacy of drawing skills for screening for autism spectrum conditions.PLoS ONE, 20(4), art. no. e0320770; 2025journal articl
Prevalence of chikungunya virus infection in Sabah, Malaysia during 2017–2020
Get PDFBackground: Chikungunya virus (CHIKV) is a mosquito-borne alphavirus and an emerging global health threat. Most research on CHIKV in Malaysia has primarily focused on Peninsular Malaysia, with limited data on its distribution in the endemic regions of Borneo, particularly Sabah. This study aimed to determine the prevalence of CHIKV infection in Sabah, Malaysia. Methods: A total of 130 serum samples, comprising 74 from febrile patients and 56 healthy individuals were collected between 2017 and 2018. Subsequently, 188 serum samples were obtained from febrile patients in Sabah, Malaysia during 2019–2020. All samples underwent quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) for the detection of the CHIKV genome. Additionally, serological tests were conducted to identify anti-CHIKV IgM and IgG antibodies. Serologically positive samples were further validated using neutralization assays to confirm the presence of CHIKV-specific antibodies. Results: In 2017–2018, 16 out of 130 samples (12.3%) tested positive for recent CHIKV infections based on CHIKV RT-qPCR or anti-CHIKV IgM results, while in 2019–2020, 7 out of 188 samples (3.7%) showed recent infections. Among the 16 recent CHIKV-positive cases in 2017–2018, four were asymptomatic individuals. In 2017–2018, 24 (18.4%) individuals tested positive for anti-CHIKV IgG, with 15 (11.5%) showing positive neutralization test results. In 2019–2020, 20 (10.6%) febrile patients were seropositive for anti-CHIKV IgG, with 17 (9.0%) showing CHIKV neutralization positivity. The CHIKV infection rate in Sabah was higher during 2017–2018 compared to 2019–2020. Conclusions: To the best of our knowledge, this is the first report confirming the presence of CHIKV in both patients and healthy individuals in Sabah using RT-qPCR and neutralization tests. Although the likelihood of transmission from asymptomatic individuals is low, they still present a considerable public health risk. Our results indicate that both basic scientists and clinicians should consider CHIKV when diagnosing febrile patients, and policymakers should put in place effective surveillance and control measures.Tropical Medicine and Health, 53(1), art. no. 55; 2025journal articl