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result(s) for
"Otelea, Dan"
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Ongoing measles outbreak in Romania: Clinical investigation and molecular epidemiology performed on whole genome sequences
2025
Romania is currently facing a prolonged measles outbreak. The aim of the study was to analyse the circulating human measles virus (HMV) strains by combining whole genome sequencing (WGS) with phylogenetic analysis, with a focus on the haemagglutinin gene.
We conducted an observational study in the first five months of 2024, in which 168 patients diagnosed with measles were randomly included. We have evaluated the clinical and epidemiological differences between children and adults. Screening for samples to be sequenced was performed with a commercial kit (PrimerDesign). WGS was done on Illumina MiSeq platform and phylogenetic analysis was performed with ML FastTree.
No significant epidemiological and clinical differences between patients in the two age groups were identified. WGS was successfully performed for a number of 124 HMV strains. Genotype analysis indicated all the sequences as D8, except one that was B3. Phylogenetic analysis identified two well supported clusters, suggestive for at least two local transmission networks in Romania. One large transmission network (n = 108) consisted of sequences both from adults and children. Only one sequence from outside Romania (reported in Russia in 2023) clustered within this group. Another small transmission cluster was identified (14 sequences of which 11 from patients infected in the spring of 2024 and three in 2022). A few differences between the two co-circulating viral variants/clusters were observed. The median duration of hospitalisation was 2 days longer for patients in smaller cluster compared to those in the larger one (p = 0.019). Furthermore, these two clusters presented different mutation profiles in the hemagglutinin (HA) and neuraminidase (N) genes with implications for molecular surveillance.
The current measles epidemic in Romania is driven mainly by two D8 genotype variants with different mutation profiles and slightly different severity of the disease, highlighting the usefulness of sustained molecular surveillance.
Journal Article
Novel Micro-LC-MS/MS Method for the Quantification of Tenofovir and Its Active Metabolite Tenofovir-Diphosphate in Biological Matrices for Therapeutic Drug Monitoring
2025
Background/Objectives: Sustained drug exposure is a key factor in the treatment of patients infected with human immunodeficiency virus (HIV) or hepatitis B virus (HBV) in order to achieve the intended virological response. Although influenced also by other parameters, adherence to the treatment scheme is the most important for adequate drug exposure. This can be assessed by therapeutic drug monitoring (TDM). Tenofovir (TFV) is a nucleotide analogue used in the treatment of both HIV and HBV. Although various analytical methods for the quantification of tenofovir prodrugs have been published, there is limited literature on methods for simultaneous TFV and its active metabolite, tenofovir diphosphate (TFVDP) direct determination. Methods: In this study, we describe a novel micro-liquid-chromatography-mass spectrometry (micro-LC-MS/MS) method for TDM of TFV and TFVDP in biological matrices (whole blood, plasma). The challenging separation of the high-polarity analytes was resolved on an amino stationary phase, eluted in HILIC (hydrophilic interaction liquid chromatography) mode. The sample preparation included a clean-up step with hexane for the removal of lipophilic compounds and then protein precipitation with organic solvent. Results: The achieved low limits of quantification in blood were 0.25 ng/mL for TFV, and 0.5 ng/mL for TFVDP. Linearity, accuracy (91.63–109.18%), precision (2.48–14.08), and stability were validated for whole blood matrix, meeting the guidelines performance criteria. Samples collected from treated patients were analyzed, with results being in accordance with the reported pharmacokinetics. Conclusions: The new method is adequate for analyzing samples in a clinical set-up. The measurement of both TFV and TFVDP improves clinical decision by an in-depth evaluation of long-term adherence, and together with viral load and resistance data helps guiding the treatment towards the intended virological suppression.
Journal Article
Evaluating HIV-1 Transmitted Drug Resistance and Clustering in Newly Diagnosed Patients in Romania (2019–2022)
by
Banica, Leontina
,
Patrascu, Raluca
,
Hohan, Robert
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2026
The HIV epidemic in Romania started in the late eighties with a large cohort of children nosocomially infected with subtype F1 strains, in parallel with sexual transmission. The purpose of the present study was to investigate the transmitted drug resistance (TDR), subtype distribution, and transmission clusters among persons diagnosed with HIV between 2019 and 2022 in Romania. The prototype of a person recently diagnosed with HIV in Romania is male, 20–50 years old, a late presenter, infected with F1, B, or A subtype. The rate of TDR varied over time, from 5% in 2019 to 15% in 2022. TDR affected mainly the first generation of NNRTIs and the PI class. The rate of late presentation was almost 60%, with 35% of persons qualifying as very late presenters. Subtype F1 is still preponderant in Romania, whereas other subtypes (B, A) and recombinants account for a quarter of HIV-1 new cases. Several transmission networks were identified in the study population, two of them associated with TDR in subtypes F1 and A1. The largest cluster consisted of 26 sequences, originating from Western Romania and introduced around 2007. Molecular clock analysis indicated different origin time points for different clusters, with the most recent in subtypes A1 and B, and the oldest in subtype F1. In conclusion, the HIV-1 epidemic in Romania is currently driven by sexual transmission, with MSM contribution continuously rising in recent years; there are also increases in TDR and the circulation of HIV-1 strains other than F1 (subtype B, A, recombinants).
Journal Article
Clinical and molecular epidemiology of influenza viruses from Romanian patients hospitalized during the 2019/20 season
2021
Two main mechanisms contribute to the continuous evolution of influenza viruses: accumulation of mutations in the hemagglutinin and neuraminidase genes (antigenic drift) and genetic re-assortments (antigenic shift). Epidemiological surveillance is important in identifying new genetic variants of influenza viruses with potentially increased pathogenicity and transmissibility. In order to characterize the 2019/20 influenza epidemic in Romania, 1042 respiratory samples were collected from consecutive patients hospitalized with acute respiratory infections in the National Institute for Infectious Diseases “Prof. Dr. Matei Balș”, Bucharest Romania and tested for influenza A virus, influenza B virus and respiratory syncytial virus (RSV) by real-time PCR. Out of them, 516 cases were positive for influenza, with relatively equal distribution of influenza A and B. Two patients had influenza A and B co-infection and 8 patients had influenza-RSV co-infection. The most severe cases, requiring supplemental oxygen administration or intensive care, and the most deaths were reported in patients aged 65 years and over. Subtyping showed the predominance of A(H3N2) compared to A(H1N1)pdm09 pdm09 (60.4% and 39.6% of all subtyped influenza A isolates, respectively), and the circulation of Victoria B lineage only. Influenza B started to circulate first (week 47/2019), with influenza A appearing slightly later (week 50/2019), followed by continued co-circulation of A and B viruses throughout the season. Sixty-eight samples, selected to cover the entire influenza season and all circulating viral types, were analysed by next generation sequencing (NGS). All A(H1N1)pdm09 sequences identified during this season in Romania were clustered in the 6b1.A clade (sub-clades: 6b1.A.183P -5a and 6b1.A.187A). For most A(H1N1)pdm09 sequences, the dominant epitope was Sb (p epitope = 0.25), reducing the vaccine efficacy by approximately 60%. According to phylogenetic analysis, influenza A(H3N2) strains circulating in this season belonged predominantly to clade 3C.3A, with only few sequences in clade 3C.2A1b. These 3C.2A1b sequences, two of which belonged to vaccinated patients, harbored mutations in antigenic sites leading to potential reduction of vaccine efficacy. Phylogenetic analysis of influenza B, lineage Victoria, sequences showed that the circulating strains belonged to clade V1A3. As compared to the other viral types, fewer mutations were observed in B/Victoria strains, with limited impact on vaccine efficiency based on estimations.
Journal Article
Whole genome sequencing snapshot of multi-drug resistant Klebsiella pneumoniae strains from hospitals and receiving wastewater treatment plants in Southern Romania
by
Sandulescu, Oana
,
Czobor Barbu, Ilda
,
Nita, Mihai
in
Aminoglycoside antibiotics
,
Aminoglycosides
,
Anti-Bacterial Agents - pharmacology
2020
We report on the genomic characterization of 47 multi-drug resistant, carbapenem resistant and ESBL-producing K. pneumoniae isolates from the influent (I) and effluent (E) of three wastewater treatment plants (WWTPs) and from Romanian hospital units which are discharging the wastewater in the sampled WWTPs. The K. pneumoniae whole genome sequences were analyzed for antibiotic resistance genes (ARGs), virulence genes and sequence types (STs) in order to compare their distribution in C, I and E samples. Both clinical and environmental samples harbored prevalent and widely distributed ESBL genes, i.e. blaSHV, blaOXA, blaTEM and blaCTX M. The most prevalent carbapenemase genes were blaNDM-1, blaOXA-48 and blaKPC-2. They were found in all types of isolates, while blaOXA-162, a rare blaOXA-48 variant, was found exclusively in water samples. A higher diversity of carbapenemases genes was seen in wastewater isolates. The aminoglycoside modifying enzymes (AME) genes found in all types of samples were aac(6'), ant(2'')Ia, aph(3'), aaD, aac(3) and aph(6). Quinolone resistance gene qnrS1 and the multi-drug resistance oqxA/B pump gene were found in all samples, while qnrD and qnrB were associated to aquatic isolates. The antiseptics resistance gene qacEdelta1 was found in all samples, while qacE was detected exclusively in the clinical ones. Trimethroprim-sulfamethoxazole (dfrA, sul1 and sul2), tetracyclines (tetA and tetD) and fosfomycin (fosA6, known to be located on a transpozon) resistance genes were found in all samples, while for choramphenicol and macrolides some ARGs were detected in all samples (catA1 and catB3 / mphA), while other (catA2, cmIA5 and aac(6')Ib / mphE and msrE) only in wastewater samples. The rifampin resistance genes arr2 and 3 (both carried by class I integrons) were detected only in water samples. The highly prevalent ARGs preferentially associating with aquatic versus clinical samples could ascribe potential markers for the aquatic (blaSHV-145, qacEdelta1, sul1, aadA1, aadA2) and clinical (blaOXA-1, blaSHV-106,blaTEM-150, aac(3)Iia, dfrA14, oqxA10; oqxB17,catB3, tetD) reservoirs of AR. Moreover, some ARGs (oqxA10; blaSHV-145; blaSHV-100, aac(6')Il, aph(3')VI, armA, arr2, cmlA5, blaCMY-4, mphE, msrE, oqxB13, blaOXA-10) showing decreased prevalence in influent versus effluent wastewater samples could be used as markers for the efficiency of the WWTPs in eliminating AR bacteria and ARGs. The highest number of virulence genes (75) was recorded for the I samples, while for E and C samples it was reduced to half. The most prevalent belong to three functional groups: adherence (fim genes), iron acquisition (ent, fep, fyu, irp and ybt genes) and the secretion system (omp genes). However, none of the genes associated with hypervirulent K. pneumoniae have been found. A total of 14 STs were identified. The most prevalent clones were ST101, ST219 in clinical samples and ST258, ST395 in aquatic isolates. These STs were also the most frequently associated with integrons. ST45 and ST485 were exclusively associated with I samples, ST11, ST35, ST364 with E and ST1564 with C samples. The less frequent ST17 and ST307 aquatic isolates harbored blaOXA-162, which was co-expressed in our strains with blaCTX-M-15 and blaOXA-1.
Journal Article
Subtypes, resistance and virulence platforms in extended-drug resistant Acinetobacter baumannii Romanian isolates
by
Lazăr, Veronica
,
Feng, Yu
,
Chifiriuc, Mariana Carmen
in
631/326
,
692/699/255
,
Acinetobacter baumannii
2021
Acinetobacter baumannii
has emerged worldwide as a dominant pathogen in a broad range of severe infections, raising an acute need for efficient antibacterials. This is the first report on the resistome and virulome of 33 extended drug-resistant and carbapenem-resistant
A. baumannii
(XDR CRAB) strains isolated from hospitalized and ambulatory patients in Bucharest, Romania. A total of 33 isolates were collected and analyzed using phenotypic antibiotic susceptibility and conjugation assays, PCR, whole-genome sequencing (WGS), pulsed-field gel electrophoresis (PFGE) and MultiLocus Sequence Typing (MLST). All isolates were extensively drug-resistant (XDR), being susceptible only to colistin. The carbapenem resistance was attributed by PCR mainly to
bla
OXA-24
and
bla
OXA-23
genes. PFGE followed by MLST analysis demonstrated the presence of nine pulsotypes and six sequence types. WGS of seven XDR CRAB isolates from healthcare-associated infections demonstrated the high diversity of resistance genes repertoire, as well as of mobile genetic elements, carrying ARGs for aminoglycosides, sulphonamides and macrolides. Our data will facilitate the understanding of resistance, virulence and transmission features of XDR AB isolates from Romanian patients and might be able to contribute to the implementation of appropriate infection control measures and to develop new molecules with innovative mechanisms of action, able to fight effectively against these bugs, for limiting the spread and decreasing the infection rate and mortality.
Journal Article
Drug Resistance Mutations for Surveillance of Transmitted HIV-1 Drug-Resistance: 2009 Update
by
Otelea, Dan
,
Sandstrom, Paul
,
Bennett, Diane E.
in
Anti-HIV Agents - pharmacology
,
Antiretroviral drugs
,
Criteria
2009
Programs that monitor local, national, and regional levels of transmitted HIV-1 drug resistance inform treatment guidelines and provide feedback on the success of HIV-1 treatment and prevention programs. To accurately compare transmitted drug resistance rates across geographic regions and times, the World Health Organization has recommended the adoption of a consensus genotypic definition of transmitted HIV-1 drug resistance. In January 2007, we outlined criteria for developing a list of mutations for drug-resistance surveillance and compiled a list of 80 RT and protease mutations meeting these criteria (surveillance drug resistance mutations; SDRMs). Since January 2007, several new drugs have been approved and several new drug-resistance mutations have been identified. In this paper, we follow the same procedures described previously to develop an updated list of SDRMs that are likely to be useful for ongoing and future studies of transmitted drug resistance. The updated SDRM list has 93 mutations including 34 NRTI-resistance mutations at 15 RT positions, 19 NNRTI-resistance mutations at 10 RT positions, and 40 PI-resistance mutations at 18 protease positions.
Journal Article
Age, comorbidity burden and late presentation are significant predictors of hospitalization length and acute respiratory failure in patients with influenza
2024
Influenza viruses are responsible for a high number of infections and hospitalizations every year. In this study, we aimed to identify clinical and host-specific factors that influence the duration of hospitalization and the progression to acute respiratory failure (ARF) in influenza. We performed an analysis of data from a prospective active influenza surveillance study that was conducted over five seasons (2018/19 to 2022/23). A total of 1402 patients with influenza were included in the analysis, the majority of which (64.5%) were children (under 18 years), and 9.1% were elderly. At least one chronic condition was present in 29.2% of patients, and 9.9% of patients developed ARF. The median hospital stay was 4 days (IQR: 3, 6 days). The most important predictors of prolonged hospital stay and development of ARF were extremes of age (infants and elderly), presence of chronic diseases, particularly the cumulus of at least 3 chronic diseases, and late presentation to hospital. Among the chronic diseases, chronic obstructive pulmonary disease, cardiovascular disease, cancer, diabetes, obesity, and chronic kidney disease were strongly associated with a longer duration of hospitalization and occurrence of ARF. In this context, interventions aimed at chronic disease management, promoting influenza vaccination, and improving awareness and access to health services may contribute to reducing the impact of influenza not only in Romania but globally. In addition, continued monitoring of the circulation of influenza viruses is essential to limit their spread among vulnerable populations.
Journal Article
Global Dispersal Pattern of HIV Type 1 Subtype CRF01_AE: A Genetic Trace of Human Mobility Related to Heterosexual Sexual Activities Centralized in Southeast Asia
by
Alexiev, Ivailo
,
Liitsola, Kirsi
,
Otelea, Dan
in
Asia, Southeastern
,
Cluster Analysis
,
Databases, Factual
2015
Background. Human immunodeficiency virus type 1 (HIV-1) subtype CRF01_AE originated in Africa and then passed to Thailand, where it established a major epidemic. Despite the global presence of CRF01_AE, little is known about its subsequent dispersal pattern. Methods. We assembled a global data set of 2736 CRF01_AE sequences by pooling sequences from public databases and patient-cohort studies. We estimated viral dispersal patterns, using statistical phylogeographic analysis run over bootstrap trees estimated by the maximum likelihood method. Results. We show that Thailand has been the source of viral dispersal to most areas worldwide, including 17 of 20 sampled countries in Europe. Japan, Singapore, Vietnam, and other Asian countries have played a secondary role in the viral dissemination. In contrast, China and Taiwan have mainly imported strains from neighboring Asian countries, North America, and Africa without any significant viral exportation. Discussion. The central role of Thailand in the global spread of CRF01_AE can be probably explained by the popularity of Thailand as a vacation destination characterized by sex tourism and by Thai emigration to the Western world. Our study highlights the unique case of CRF01_AE, the only globally distributed non-B clade whose global dispersal did not originate in Africa.
Journal Article
Epidemic dispersion of HIV and HCV in a population of co-infected Romanian injecting drug users
by
Banica, Leontina
,
Abagiu, Adrian
,
Nicolae, Ionelia
in
Acquired immune deficiency syndrome
,
Adult
,
AIDS
2017
Co-infections with HIV and HCV are very frequent among people who inject drugs (PWID). However, very few studies comparatively reconstructed the transmission patterns of both viruses in the same population. We have recruited 117 co-infected PWID during a recent HIV outbreak in Romania. Phylogenetic analyses were performed on HIV and HCV sequences in order to characterize and compare transmission dynamics of the two viruses. Three large HIV clusters (2 subtype F1 and one CRF14_BG) and thirteen smaller HCV transmission networks (genotypes 1a, 1b, 3a, 4a and 4d) were identified. Eighty (65%) patients were both in HIV and HCV transmission chains and 70 of those shared the same HIV and HCV cluster with at least one other patient. Molecular clock analysis indicated that all identified HIV clusters originated around 2006, while the origin of the different HCV clusters ranged between 1980 (genotype 1b) and 2011 (genotypes 3a and 4d). HCV infection preceded HIV infection in 80.3% of cases. Coincidental transmission of HIV and HCV was estimated to be rather low (19.65%) and associated with an outbreak among PWID during detention in the same penitentiary. This study has reconstructed and compared the dispersion of these two viruses in a PWID population.
Journal Article