Diagnosis Of Virus Research Articles

Advancements in LAMP-Based Diagnostics: Emerging Techniques and Applications in Viral Detection with a Focus on Herpesviruses in Transplant Patient Management

Loop-mediated isothermal amplification (LAMP) is a highly effective molecular diagnostic technique, particularly advantageous for point-of-care (POC) settings. In recent years, LAMP has expanded to include various adaptations such as DARQ-LAMP, QUASR, FLOS-LAMP, displacement probes and molecular beacons. These methods enable multiplex detection of multiple targets in a single reaction, enhancing cost-effectiveness and diagnostic efficiency. Consequently, LAMP has gained significant traction in diagnosing diverse viruses, notably during the COVID-19 pandemic. However, its application for detecting Herpesviridae remains relatively unexplored. This group of viruses is of particular interest due to their latency and potential reactivation, crucial for immunocompromised patients, including organ and hematopoietic stem cell transplant recipients. This review highlights recent advancements in LAMP for virus diagnosis and explores current research trends and future prospects, emphasizing the detection challenges posed by Herpesviridae.

Wheat Germ Agglutinin-Modified "Three-in-One" Multifunctional Probe Driven Broad-Spectrum and Flexible Immunochromatographic Diagnosis of viruses With High Sensitivity.

The conventional lateral flow assay (LFA) fails to the demands for the accurate screening of viruses as a result of its low sensitivity of colorimetric signal output and poor universality limited by antibody pairs. Here, a magnetically assisted dual-signal output LFA platform is developed for the ultrasensitive, universal, and flexible detection of viruses. A "three-in-one" multifunctional probe (MAuDQD) is prepared using a 180nm Fe3O4 core to load numerous Au nanoparticles (NPs) and two layers of QDs, which can substantially improve the sensitivity of LFA through coupling with the effects of magnetic enrichment and colorimetric/fluorescent enhancement. Wheat germ agglutinin (WGA)-modified MAuDQD attained the broad-spectrum capture viral membrane proteins and the colorimetric/fluorescent dual-mode detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and monkeypox virus (MPXV) on the LFA strip. In the colorimetric mode, the target viruses detected directly, with the visual sensitivity reaching 0.1-0.5ngmL-1 and the fluorescent mode supported quantitative analysis of SARS-CoV-2/MPXV with limits of detection decreasing to pgmL-1 level. Practicability of the MAuDQD@WGA-LFA is verified through the detection of 33 real clinical samples, showing the proposed assay has a great potential to become a sensitive, accurate, and universal tool for on-site monitoring of viral infections.

Toward Universal Health Coverage: What Socioeconomic and Clinical Factors Influence Health Insurance Coverage and Restrictions in Access to Viral Hepatitis Services in Nasarawa State, Nigeria?

Background: Viral hepatitis B and C (HBV and HCV) pose significant public health concern in Nigeria, where access to healthcare and treatment affordability are limited. This study investigated sociodemographic and clinical predictors of health insurance coverage and access to care among patients with HBV and HCV in Nasarawa State, Nigeria. Methods: A cross-sectional facility-based study was conducted at two secondary hospitals in Nasarawa State, Nigeria. Participants included patients diagnosed with HBV, HCV, or both who were ≥18 years old. Data were collected using a structured questionnaire covering sociodemographic and clinical information, health insurance details, and economic impact. Binary logistic regression was used to analyze the relationship between sociodemographic/clinical factors and health insurance status. Results: Out of 303 participants, 68% had health insurance, which mostly covered hepatitis screening and vaccination. Significant predictors of health insurance coverage included being aged 36-40 years (adjusted odds ratio [aOR]: 11.01, 95% confidence interval [CI]: 2.38-50.89, p = 0.002), having post-secondary education (aOR: 25.2, 95% CI: 9.67-65.68, p < 0.001), being employed (aOR: 27.83, 95% CI: 8.85-87.58, p < 0.001), and being HIV-positive (aOR: 4.06, 95% CI: 1.55-10.61, p = 0.004). Nearly all those insured (99%) faced restrictions in insurance coverage for viral hepatitis services. Conclusions: This study reveals that while health insurance coverage is relatively high among viral hepatitis patients in Nasarawa State, significant restrictions hinder access to comprehensive services, especially for vulnerable groups like younger adults, the unemployed, and PLHIV. Key factors influencing coverage include age, education, employment, and HIV status. Expanding benefit packages to include viral hepatitis diagnosis and treatment, raising awareness about viral hepatitis as part of insurance strategy, improving access for underserved populations, and integrating hepatitis services into existing HIV programs with strong policy implementation monitoring frameworks are crucial to advancing universal health coverage and meeting the WHO's 2030 elimination goals.

First report of lily mottle virus naturally infecting lily (Lilium asiatica) in Texas, USA.

Lily (Lilium asiatica) is an important plant grown for its range of flower colors and heavy scent. In March 2024, potyvirus-like symptoms consisting of light-yellow mottling and mosaic were noticed on 12/20 lily plants in a private property in Weslaco, Hidalgo County, Texas. Two symptomatic plants (WTX1 and WTX2) were sampled randomly for virus diagnosis. The leaf extracts of both samples were negative for the potyvirus group using Agdia's Poty ImmunoStrip® (Agdia, Inc., Elkhart, IN, USA). However, rub-inoculation of the extracts onto healthy Nicotiana benthamiana and Vigna unguiculata plants (n=4, each) induced mild mottle symptoms on the systemic leaves of both herbaceous test plants 20 to 28 days post inoculation, indicating the presence of a mechanically transmissible agent in the samples. No virus-like symptoms were observed on the mock-inoculated plants (n=1, each) of both species. To test for suspected potyvirus infection, 2-µg of total nucleic acid extracts (Dellaporta et al. 1983) from WTX1 and WTX2 were used for complimentary DNA (cDNA) synthesis with Oligo(dT) primer and the PrimeScript 1st strand cDNA synthesis kit (Takara Bio, USA). One microliter aliquot of each cDNA served as template in 12.5-µl conventional PCR reaction volumes with 5 U Taq polymerase (Roche Diagnostics, Indianapolis, IN), and two pairs of degenerate primers targeting the partial cylindrical inclusion (CI) gene and the helper component protease (HC-Pro) of potyviruses (Ha et al. 2008). The expected ~700-bp DNA product of each gene target was amplified from both samples. The amplicons were excised, gel eluted (Zymoclean™ Gel DNA Recovery kit) and cloned individually into the pJET1.2/Blunt vector (Life Technologies). Recombinant plasmids from two transformed Escherichia coli cells per cloned DNA insert were Sanger sequenced. BLASTn analysis of each gene-specific nucleotide (nt) sequence fragment revealed their identities (83 to 92 % nt) as lily mottle virus (LMoV; genus Potyvirus) at 93 to 98% query coverage. In pairwise comparison, the obtained sequences of LMoV isolates from TX specific to the CI (GenBank accession nos. PQ037260-61) and the HC-Pro (PQ037262-63) shared ~99% nt and 100% amino acid (aa) identities with each other and ~91-92% nt and 98-100% aa identities with the closest isolate, Bate5 (JN127341) from Australia. Based on these results, a pair of LMoV-specific primers (LM_v109-F: 5'-GGCCAGTAATGTGCACAAGC-3' and LM_c527-R: 5'-TCGCTGTAGCTAGCGACGTAC-3') was newly designed to target the partial CI gene, internal to the 700-bp fragment obtained above with the generic primers. The primer pair was used to screen each of the mechanically inoculated test plants by RT-PCR as previously described above. The expected 438-bp fragment of the LMoV CI gene was amplified from all the inoculated plants of both N. benthamiana and V. unguiculata; the results were confirmed by Sanger sequencing as described above. The mock-inoculated plant of each experimental host plant tested negative for LMoV. LMoV is a quarantine pest and was previously reported in the U.S. (Brierley and Smith, 1944) and other lily-producing parts of the world, such as the Netherlands, China, Korea, and Brazil. To our knowledge, this is the first confirmed report of the virus in Texas, thus expanding its geographical range. Testing of lily foundation stocks before propagation is essential to prevent further spread of LMoV via planting material.

Meningitis after COVID-19 vaccination, a systematic review of case reports and case series

IntroductionVaccination is considered as one of the most promising strategies to overcome the COVID-19 pandemic. However, it could be associated with rare but serious complications. In the present study, we aimed to review the clinical course and etiology of post COVID-19 vaccination meningitis.MethodsAfter a systematic search in PubMed, Scopus, and Web of Sciences online databases as well as Google Scholar, documents were screened and qualified. Then data extraction was performed and the most frequent underlying agent of meningitis was found based on the reported cases.ResultsOverall, 35 cases of post COVID-19 vaccination meningitis from 33 articles were included in the review. Among them, 12 cases had proven viral diagnosis and 23 of them were reported to be vaccine-induced. The most frequent viral pathogen among the cases was VZV. The most prevalent symptom was headache, and the most common time of appearance symptoms was one week after vaccination.ConclusionOverall, our study suggested meningitis as a critical but not devastating complication of COVID-19 vaccination. Almost all patients responded well to common agents used to manage viral or vaccine-induced meningitis. It is recommended to monitor patients with a history of chickenpox after COVID-19 vaccination regarding the development of meningitis.

Respiratory virus behavior: Results of laboratory-based epidemiological surveillance.

Respiratory viruses have clinical and epidemiological importance. With the COVID-19 pandemic, interest has focused on SARS-CoV-2, but as a result, the number of samples available for the differential diagnosis of other respiratory viruses has increased. Cross-sectional study. To describe the epidemiological behavior of respiratory viruses based on a laboratory-based epidemiological surveillance system using data from 2017 to 2023. Univariate, bivariate and multivariate analyses of data from a laboratory database of respiratory viruses detected by multiplex RT‒qPCR were performed. A total of 4,632 samples with positive results for at least 1 respiratory virus, not including influenza or SARS-CoV-2, were analyzed. The most common virus detected was respiratory syncytial virus in 1,467 (26.3%) samples, followed by rhinovirus in 1,384 (24.8%) samples. Most of the samples were from children under 5 years of age. The age-adjusted odds ratio (OR) of death for patients infected with parainfluenza virus 4 was 4.1 (95% confidence interval [95% CI] 2.0-8.2). Respiratory syncytial virus and rhinovirus had the highest frequency and proportion of coinfections, whereas parainfluenza virus 4 was associated with an increased risk of death.

Molecular diagnosis of human papilloma virus (HPV) genotypes in women with genital warts in Mosul / Iraq

Molecular diagnosis of human papilloma virus (HPV) genotypes in women with genital warts in Mosul / Iraq

Dually-amplified electrochemical aptasensor based on the self-linking AuPt nanoflowers for ultrasensitive determination of hemagglutinin

BackgroundInfluenza virus can spread from person to person and cause epidemics. Therefore, rapid and sensitive diagnosis of virus is essential in controlling influenza outbreaks. Conventional virus diagnostic techniques are time-consuming, labor-intensive and requires large instruments. In this work, a sandwich electrochemical assay by a pair of aptamers was developed for ultrasensitive determination of hemagglutinin (HA) protein, which is one of the two surface glycoproteins of influenza A (H1N1) virus, using dual signal amplification techniques. ResultsHA was captured and magnetically separated by Fe3O4@SiO2–NH2@Au attached to aptamer 1 (Apt1), creating a sandwich structure with AuPt nanoflowers (AuPtNFs) connected to aptamer 2 (Apt2). Herein, AuPtNFs could catalyze H2O2/hydroquinone (HQ) to generate 1,4-benzoquinone (BQ), and achieved amplification of electrochemical signal detection through differential pulse voltammetry (DPV). The constructed aptasensor expressed a wide linear range (10 pg/mL-100 ng/mL) with limit of detection (LOD) of 2.4 pg/mL. Moreover, a novel strategy for dual signal amplification was developed to further enhance sensitivity. The innovative electrochemical aptasensor could achieve secondary amplification of the detection signal with LOD of 0.3 pg/mL and linear concentration range from 0.5 pg/mL to 100 ng/mL. The secondary amplification could be achieved only through the self-linking process, which allowed for the retention of numerous AuPtNFs by simple complementary base pairing to connect more AuPtNFs onto the above-mentioned sandwich structure. SignificanceOverall, the constructed aptasensor exhibited favorable sensitivity and accuracy, indicating the potential expanded application for the clinical detection of numerous viruses.

Intelligent Analysis of Avian Influenza Virus Biomarkers Based on Chemiluminescence Resonance Energy Transfer and DNA Logic Analysis.

A one-step logical analysis of multiple targets remains challenging. Herein, we report a one-pot and intelligent DNA logical analysis platform for the diagnosis of avian influenza virus (AIV) biomarkers based on chemiluminescence resonance energy transfer (CRET) and logic operations. On the surface of Lum/PEI/CaCO3 microparticles, the excited state of luminol underwent CRET with fluorescein isothiocyanate or rhodamine B isothiocyanate, producing three well-separated light emissions at 425, 530, and 590 nm, respectively. Taking advantage of the close distance between fluorophores aligned by the catalytic hairpin assembly reaction, the CRET efficiency was greatly enhanced (53.1%). H1N1, H7N9, and H5N1 were detected with limits of detection values as low as 15, 34, and 58 pM, respectively. Three-input logic circuits were simultaneously conducted on the surface of Lum/PEI/CaCO3 microparticles, enabling the rapid and accurate discrimination of multiple AIV biomarkers in one solution. In terms of peak positions and the normalized value of the total peak intensity, three biomarkers can be simultaneously discriminated without any other complex operations. In summary, the CRET-based multiple analytical assay was developed as an intelligent biosensor for identifying AIV biomarkers, having promising application prospects in the field of multiple analysis and precise disease diagnosis.

Evaluating metagenomics and targeted approaches for diagnosis and surveillance of viruses

BackgroundMetagenomics is a powerful approach for the detection of unknown and novel pathogens. Workflows based on Illumina short-read sequencing are becoming established in diagnostic laboratories. However, high sequencing depth requirements, long turnaround times, and limited sensitivity hinder broader adoption. We investigated whether we could overcome these limitations using protocols based on untargeted sequencing with Oxford Nanopore Technologies (ONT), which offers real-time data acquisition and analysis, or a targeted panel approach, which allows the selective sequencing of known pathogens and could improve sensitivity.MethodsWe evaluated detection of viruses with readily available untargeted metagenomic workflows using Illumina and ONT, and an Illumina-based enrichment approach using the Twist Bioscience Comprehensive Viral Research Panel (CVRP), which targets 3153 viruses. We tested samples consisting of a dilution series of a six-virus mock community in a human DNA/RNA background, designed to resemble clinical specimens with low microbial abundance and high host content. Protocols were designed to retain the host transcriptome, since this could help confirm the absence of infectious agents. We further compared the performance of commonly used taxonomic classifiers.ResultsCapture with the Twist CVRP increased sensitivity by at least 10–100-fold over untargeted sequencing, making it suitable for the detection of low viral loads (60 genome copies per ml (gc/ml)), but additional methods may be needed in a diagnostic setting to detect untargeted organisms. While untargeted ONT had good sensitivity at high viral loads (60,000 gc/ml), at lower viral loads (600–6000 gc/ml), longer and more costly sequencing runs would be required to achieve sensitivities comparable to the untargeted Illumina protocol. Untargeted ONT provided better specificity than untargeted Illumina sequencing. However, the application of robust thresholds standardized results between taxonomic classifiers. Host gene expression analysis is optimal with untargeted Illumina sequencing but possible with both the CVRP and ONT.ConclusionsMetagenomics has the potential to become standard-of-care in diagnostics and is a powerful tool for the discovery of emerging pathogens. Untargeted Illumina and ONT metagenomics and capture with the Twist CVRP have different advantages with respect to sensitivity, specificity, turnaround time and cost, and the optimal method will depend on the clinical context.

Early diagnosis of Chikungunya virus utilizing square core photonic crystal fiber (SC-PCF) with extremely high relative sensitivity

Chikungunya virus (CHIKV) poses a significant public health threat due to its capacity to cause widespread and debilitating outbreaks. The virus is responsible for CHIKV fever, a disease characterized by severe joint pain, sudden onset of fever, headache, muscle pain, and rash. The virus has been reported in various regions globally, with outbreaks occurring in parts of Africa, Asia, the Americas, and the Indian subcontinent. Consequently, the scientific community expends substantial efforts in developing dependable, rapid, highly sensitive, and cost-effective techniques in order to identify the CHIKV virus. In this study, an innovative biomedical sensor using photonic crystal fiber technology enables precise detection of the CHIKV virus through uric acid, normal and infected plasma, red blood cells, and platelets in the blood. The introduced sensor identifies those kinds with extremely increased relative sensitivity and minimal losses in contrast to alternative photonic crystal fiber-based biosensors. The introduced sensor showcases a minimal confinement loss of 2.25 × 10− 13 cm− 1, a relative sensitivity of 99.37%, an effective area of 1.36 × 105 µm2, with a minimal effective material loss of 0.001966 cm–1, a numerical aperture of 0.1874, and low dispersion of 0.06. Also, the demonstrated sensor is able to function within the terahertz spectrum, covering a substantial span from 0.8 to 2.6 THz. Furthermore, an extensive comparison analysis is performed between the showcased sensor and related literature on photonic crystal fibers to verify the reliability and effectiveness of the introduced structure.

Выявление патогенов картофеля с использованием различных методов диагностики

Abstract. Potato diseases have far reaching implications for the agricultural industry as they not only reduce productivity and quality of potato crop but also negatively affect the livelihood of farmers. The purpose of the studies detection and identification of potato phytopathogens by visual assessment, real time polymerase chain reaction (PCR) and molecular genetic screening for phytopathogen resistance genes. Methods. Visual evaluation of each potato variety for major fungal, viral and bacterial diseases was carried out during the period of full sprouting, at plant height of 15–20 cm and in the phase of full flowering. The percentage of plants affected by diseases in relation to the total number of inspected plants was calculated. Diagnosis of resistance of potato samples to diseases was carried out on the basis of PCR. DNA markers of phytopathogen resistance genes YES3-3A, RYSC3, Ry186, TG 689, Gro1-4-1, Gpa2-2, PVX were used for molecular screening of potato. Infection of samples by PCR-RV (real-time) was determined using reagent kits of Syntol LLC Potato Virus X and Potato Virus Y, Potato spindle tuber viroid-PB, Clavibacter michiganensis subsp. sepedonicus-PB, Dickeya spp-PB. Results. According to the results of visual evaluation, the absence of symptoms of wrinkle mosaic in 20% of hybrids, mottle mosaic in 40%, mosaic leaf curl in 96 %, leaf curl in 72 hybrids, black leg in 100%, phytophthorosis in 88% of hybrids, alternaria in 84 %, rhizoctoniosis in 96 % of hybrids were observed. According to the results of PCR-RV analysis in 21 samples detected virus Y. The scientific novelty consists in the diagnosis of potato viruses using traditional visual assessment with the use of molecular markers that allow to identify correlation relationship between trhis methods.

Validation of a direct multiplex real-time reverse transcription PCR assay for rapid detection of African swine fever virus using swine field samples in Vietnam

ObjectiveThis study validates a direct multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assay which was previously established for enabling rapid and simultaneous detection of African swine fever (ASF) virus (ASFV) and classical swine fever virus. The assay eliminates the need for viral nucleic acid purification using a buffer system for crude extraction and an impurity-tolerant enzyme. However, the assay had not yet been validated using field samples of ASFV-infected pigs. Therefore, to address this gap, we tested 101 samples collected from pigs in Vietnam during 2018 and 2021 for validation.ResultsThe rRT-PCR assay demonstrated a diagnostic sensitivity of 98.8% and a specificity of 100%. Remarkably, crude samples yielded results comparable to those of purified samples, indicating the feasibility of using crude samples without compromising accuracy in ASFV detection. Our findings emphasize the effectiveness of the rRT-PCR assay for the prompt and accurate diagnosis of both swine fever viruses, which is essential for effective disease prevention and control in swine populations.

Multilocular subcutaneous bacillary angiomatosis as a primary manifestation of AIDS

AbstractA 34‐year‐old male patient presented with a clinical picture of multilocular subcutaneous skin nodules in addition to marked lymphadenopathy and general physical deterioration. A comprehensive diagnostic workup including serology, skin biopsy and imaging studies led to the initial diagnosis of human immunodeficiency virus (HIV) infection in AIDS stage with rare multilocular subcutaneous bacillary angiomatosis (BA) caused by Bartonella henselae. BA describes a process of neovascularisation of the skin or of internal organs (particularly the liver and spleen) and was first described in HIV‐positive patients by Stoler et al. in 1983. Both cutaneous and systemic symptoms are variable. There is no standardized treatment. The patient was started on antibiotic therapy with doxycycline, which was subsequently augmented with rifampicin. As the patient's general condition deteriorated and lymphocytopenia aggravated, he was transferred to an internal medicine ward for further treatment and subsequently commenced on antiretroviral therapy. This case corroborates numerous aspects of the cases described in the literature yet differs from them in that subcutaneous lesions are uncommon, particularly when infected with Bartonella henselae, illustrating the clinical spectrum of BA. Furthermore, it emphasises the significance of prompt and thorough diagnosis encompassing HIV serology in instances of skin lesions, accompanied by systemic signs and evidence of immunosuppression.

A novel high-performance rapid screening test for the detection of total HTLV-I and HTLV-II antibodies in HTLV-I/II infected patients

Rapid diagnosis of human T-cell lymphotropic virus (HTLV) type-I and -II infections are essential for timely and cost-effective disease interventions. MP Diagnostics ASSURE HTLV-I/II Rapid Test was developed for the rapid detection of anti-HTLV-I/II antibodies in patients’ serum, plasma, and whole blood specimens. ASSURE HTLV-I/II Rapid Test employed MP Biomedicals’ proprietary HTLV-I/II Trifusion recombinant antigen conjugated with gold nanoparticles and HTLV-I / HTLV-II recombinant antigens immobilized on the nitrocellulose membrane to detect total HTLV-I and HTLV-II antibodies. The overall performance of the ASSURE HTLV-I/II Rapid Test was found to be 99.42% sensitivity (95% Confidence Interval, 98.32–99.88%) and 100% specificity (95% Confidence Interval, 99.58–100.00%) in the tested clinical samples, including a total of 518 HTLV-I/II positive specimens (396 HTLV-I infection, 97 HTLV-II infection and 25 HTLV-I/II dual infection) and 872 HTLV negative clinical specimens consisting of 691 healthy donor samples, 116 potentially cross-reactive samples, and 65 samples with interfering substances. The ASSURE HTLV-I/II Rapid Test can effectively be deployed as a screening tool in any prevalence studies, blood banks or organ transplant centres.

Prevalence and Seasonal Patterns of 16 Common Viral Respiratory Pathogens during the COVID-19 Pandemic in Gauteng Province, South Africa, 2020-2021.

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The COVID-19 pandemic resulted in widespread morbidity and mortality, but generally, the diagnosis of other respiratory viruses was limited. This study aimed to assess the prevalence of other respiratory viruses during the 2020/2021 pandemic among patients of all ages who accessed care at public healthcare facilities in Gauteng Province, South Africa. Laboratory diagnosis for respiratory viruses, with or without SARS-CoV-2, was conducted via multiplex real-time polymerase chain reactions using respiratory specimens. A total of 1776 patients were included from 1 April 2020 to 31 March 2021, of which 766 (43.1%) were positive for respiratory viruses other than SARS-CoV-2. RV (368/1776; 20.7%) was the most prevalent, followed by RSV (304/1776; 17.1%), AdV (112/1776; 6.3%) and EV (105/1776; 5.9%). hCoV-OC43 (39/1776; 2.2%) was the most prevalent common coronavirus. SARS-CoV-2 co-infections were detected in 4.8% (24/500) of patients. Only 27.1% (482/1776) of patients were admitted to high-care or intensive care units. A decrease in respiratory virus detections was observed, except for RSV, EV and hCoV-OC43. RSV prevalence increased in 2021, while influenza A/B viruses remained undetected.

Viral Co-Infection Diagnosis in Cervical Samples Using Next Generation Sequencing Technology

Viral Co-Infection Diagnosis in Cervical Samples Using Next Generation Sequencing Technology

Increased production of orthoflavivirus single-round infectious particles produced in mammalian cells at a suboptimal culture temperature of 28°C

In the employment of serodiagnostic methods for the detection of orthoflavivirus infections, neutralization tests are known to be more accurate than measurements of antibody binding properties employing enzyme-linked immunosorbent assays. However, neutralization tests require infectious virus and laboratories with an appropriate level of biosafety. Single-round infectious particles (SRIPs), which encode a reporter gene instead of the viral structural protein genes, are replication incompetent and represent a safe and reliable alternative to the diagnosis of pathogenic viruses in neutralization tests. The orthoflavivirus SRIPs are produced by co-transfection of plasmids expressing virus-like particles and replicons into mammalian cell lines preferably with high transfection efficacy, such as HEK293T cells. However, certain orthoflavivirus SRIPs have limitations in their efficient expression at 37°C, which is the optimal temperature for mammalian cell growth, resulting in insufficient yields for neutralization tests. Here, we demonstrate that the production of orthoflavivirus SRIPs increases at the lower temperature of 28°C compared to 37°C. Moreover, infections with 28°C-cultured SRIPs in microneutralization tests were specifically inhibited in the presence of serum from mice infected with homologous viruses, suggesting that these SRIPs preserved their neutralizing epitopes for antibodies. Our method to produce high titer SRIPs is anticipated to promote efficient and safe SRIPs neutralization tests as a general serodiagnostic method for detecting virus-specific neutralizing antibodies against orthoflaviviruses.

Missed Opportunities for HIV Diagnosis and Their Clinical Repercussions in the Portuguese Population-A Cohort Study.

Late human immunodeficiency virus (HIV) diagnosis has been associated with missed opportunities for earlier diagnosis. We conducted a retrospective, longitudinal, single-centre cohort study evaluating these missed opportunities and their clinical repercussions in adults with a new HIV diagnosis or who were drug-naïve, who attended our Infectious Diseases Department between 2018 and 2023. We assessed missed opportunities in the two years prior to diagnosis or after the last negative HIV test. We compared clinical and laboratorial data from individuals with and without missed opportunities. The primary outcome considered was AIDS-defining conditions at diagnosis. Among the 436 included individuals, 27.1% experienced at least one missed opportunity. Those with missed opportunities were more likely to be female (p = 0.007), older at their first consultation (p < 0.001), born in Africa (p < 0.001) and in countries with a high HIV prevalence (p < 0.001), and have heterosexual transmission (p < 0.001). The adjusted analysis showed that missed opportunities were significantly associated with AIDS-defining conditions at diagnosis (OR 3.23, CI 95% [1.62-6.46], p < 0.001). These findings highlight the impact of missed opportunities on HIV severity, underscoring the need for more targeted interventions to reduce them.

Quantifying the long-term effects of measles infection—a retrospective cohort study

ObjectivesTo assess whether measles infection has an impact on the rate of non-measles infectious diseases over an extended period. MethodsThis retrospective matched cohort study included 532 measles-diagnosed patients who were exactly matched with 2128 individuals without a previous measles diagnosis. Adjusted OR for any all-cause infectious diagnosis and any viral infection diagnosis ≤2 years after measles diagnosis between the measles and control groups was obtained from a conditional logistic regression model. The Cox proportional hazards model was used to estimate the hazard ratio. ResultsPrevious measles virus (MeV) exposure was associated with an increased risk for all-cause non-measles infectious disease diagnosis (OR: 1.83, 95% CI: 1.26–2.64, p 0.001), with 492 diagnoses in the MeV-exposed group and 1868 diagnoses in the control group. Additionally, previous MeV exposure was linked to a higher risk of viral infection diagnosis (OR: 1.23, 95% CI: 1.01–1.59, p < 0.05), with 302 viral infection diagnoses in the MeV-exposed group and 1107 diagnoses in the control group. The hazard ratio for viral diagnosis in the MeV-exposed group compared with the control group was 1.54 (95% CI: 1.18–2.02, p < 0.001). DiscussionIndividuals diagnosed with measles had a moderately increased risk of being diagnosed with all-cause non-measles infectious disease or viral infection. This observational individual-level study supports previous ecological and individual population-level studies.