Acute hepatitis B outbreak in a nursing home for the disabled in Türkiye.

Background: Although hepatitis B is vaccine-preventable, it remains a significant health problem. To the best of our knowledge, this is the first hepatitis B outbreak report from Türkiye. Aims: To investigate the cause of hepatitis B outbreak in a nursing home for the disabled and make recommendations for prevention. Methods: An outbreak of acute hepatitis B was declared in a nursing home for the disabled following the admission of 3 patients from the home in a hospital. Collaborative response was initiated with the Provincial Health Directorate through the Public Health Infectious Diseases Department. We began tracking the infection and monitoring active cases. Audits and controls were carried out to determine the source, establish protection and control measures, and prevent further transmission. Results: Six of the 65 nursing home residents were diagnosed with acute hepatitis B. Four of them had diabetes and their blood glucose levels were monitored for at least 12 months. Two of the patients had received dental treatment in the last 6 months. The frequency of both variables, which may be an indication of the transmission route, was statistically significantly greater in the acute hepatitis B group. All the patients who could be sequenced were identified as genotype D. While 3 patients recovered fully, 2 were diagnosed with chronic hepatitis B and one died due to fulminant hepatitis. Conclusion: Standard routine immunization should be implemented as a preventive measure for acute hepatitis B. Frequent supervision and training on hygiene practices and safety precautions should be conducted for care staff working in collective residential facilities.

Molecular Epidemiology of HIV-1 Subtypes and Primary Antiretroviral Resistance Profiles in Northern Cyprus: First Data Series.

The distribution of human immunodeficiency virus-1 (HIV-1) subtypes indicates difference from region to region and in risk groups acquiring the disease worldwide. Although subtype C is more in terms of total cases, subtype B is dominant in certain regions, especially in western and central Europe. Molecular epidemiological studies are essential for the control, effective treatment, and understanding in transmission routes of HIV-1 infection. This study aims to determine the molecular epidemiology and antiretroviral drug resistance profiles of HIV-1 in northern Cyprus. The study involved 71 naive HIV-positive patients diagnosed in northern Cyprus between 2016 and 2022. HIV-1 subtypes and circulating recombinant forms (CRFs) were identified by phylogenetic analysis (neighbor-joining method) of pol gene sequences. Drug resistance mutations were analyzed using the World Health Organization (WHO) lists of mutations for surveillance. The Stanford University HIVdb program was used to interpret drug resistance mutations. In our study, 40 of 71 samples were successfully sequenced. Subtype B of HIV-1 was dominant with a rate of 52.5%, followed by CRF02_AG (20%) and G (7.5%) subtypes. The rate of subtype B (71.4%) in northern Cyprus was significantly higher than in the other country of origin (p = .028). Antiretroviral drug resistance was found in 15% of the sequenced serum samples. Nucleoside/nucleotide reverse transcriptase inhibitor (NRTI), non-nucleoside nucleotide reverse transcriptase inhibitor (NNRTI), and protease inhibitor (PI) resistance rates were 10% (4/40), 7.5% (3/40), and 2.5% (1/40), respectively. According to the results, it is noteworthy that the dominant subtype circulating in northern Cyprus is the B subtype, and CRFs were detected at a higher rate than expected.

Molecular Epidemiology of SARS-CoV-2 Omicron Sub-Lineages Isolated from Turkish Patients Infected with COVID-19.

Early detection and characterization of new variants and their impacts enable improved genomic surveillance. This study aims to evaluate the subvariant distribution of Omicron strains isolated from Turkish cases to determine the rate of antiviral resistance of RdRp and 3CLpro inhibitors. The Stanford University Coronavirus Antiviral & Resistance Database online tool was used for variant analyses of the strains uploaded to GISAID as Omicron (n = 20.959) between January 2021 and February,2023. Out of 288 different Omicron subvariants, B.1, BA.1, BA.2, BA.4, BE.1, BF.1, BM.1, BN.1, BQ.1, CK.1, CL.1, and XBB.1 were the main determined subvariants, and BA.1 (34.7%), BA.2 (30.8%), and BA.5 (23.6%) were reported most frequently. RdRp and 3CLPro-related resistance mutations were determined in n = 150, 0.72% sequences, while the rates of resistance against RdRp and 3CLpro inhibitors were reported at 0.1% and 0.6%, respectively. Mutations that were previously associated with a reduced susceptibility to remdesivir, nirmatrelvir/r, and ensitrelvir were most frequently detected in BA.2 (51.3%). The mutations detected at the highest rate were A449A/D/G/V (10.5%), T21I (10%), and L50L/F/I/V (6%). Our findings suggest that continuous monitoring of variants, due to the diversity of Omicron lineages, is necessary for global risk assessment. Although drug-resistant mutations do not pose a threat, the tracking of drug mutations will be necessary due to variant heterogenicity.

In Silico Evaluation of SARS-CoV-2 K417N, L452R, and E484K Detection Assays Against Omicron Variants.

The study's objective was to assess whether the performance of the DIAGNOVITAL SARS-CoV-2 Mutation Detection Assays is affected by Omicron mutations. In silico evaluation of 67,717 Variant of Concern, Variant of Interest sequences and 6,612 sequences of the Omicron variants involving BA1., BA2., BA3 sub-lineages downloaded from the GISAID database by 17 December 2021, were performed. The sequences were aligned according to the reference genome MN908947.3 using MAFFT multiple sequence alignment software version 7. Our findings showed that among 6,612 Omicron, 41 Spike gene mutations with a frequency of ≥70% were identified. Some of the Omicron mutations (R408S, N440K, G446S, Q493S, Q498R) could affect the diagnostic performance of K417N, L452R, and E484K assays against the Omicron sub-lineages. However, L452R and K417N mutation tests allow differentiation of the Delta and Omicron variants mutation profile. The COVID-19 pandemic lasted longer than expected, and the rapid modification of diagnostic kits seems necessary to combat the pandemic.

Evaluation of lateral flow and ELISA techniques for detecting IgG and IgM antibodies in COVID-19 cases in Türkiye.

Background: Antibody testing can complement molecular assays for detecting COVID-19. Aims: We evaluated the concurrence between lateral flow assay and enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Methods: The study was conducted at Kocaeli University, Türkiye. We used a lateral flow assay and ELISA to test serum samples from COVID-19 cases, confirmed by polymerase chain reaction assays (study group) and pre-pandemic stored serum samples (control group). We used Deming regression to evaluate the antibody measurements. Results: The study group included 100 COVID-19 cases, and the control group included pre-pandemic samples from 156 individuals. The lateral flow assay detected immunoglobulin M (IgM) and G (IgG) antibodies in 35 and 37 study group samples. ELISA detected IgM nucleocapsid (N) antibodies in 18 samples, and IgG (N) and IgG spike 1 (S1) antibodies in 31 and 29 samples, respectively. None of the techniques detected antibodies in the control samples. Strong correlations were found between lateral flow IgG (N+ receptor-binding domain + S1) and ELISA IgG (S) (r = 0.93, P < 0.01) and ELISA IgG (N) (r = 0.81, P < 0.01). Weaker correlations were seen between ELISA IgG S and IgG N (r = 0.79, P < 0.01) and lateral flow assay and ELISA IgM (N) (r = 0.70, P < 0.01). Conclusion: Lateral flow assay and ELISA techniques gave consistent results for IgG/IgM antibody measurements towards spike and nucleocapsid proteins, suggesting that both methods can be used to detect COVID-19 where access to molecular test kits is difficult.

Dynamics of Rilpivirine Resistance-Associated Mutation: E138 in Reverse Transcriptase among Antiretroviral-Naive HIV-1-Infected Individuals in Turkey.

Rilpivirine, one of the non-nucleoside reverse transcriptase inhibitors class anti-HIV agents, is used as an alternative drug to treat HIV-1-positive individuals according to current antiretroviral therapy (ART) guidelines. Mutation in the position E138 in HIV-1 reverse transcriptase (RT) leads to resistance to rilpivirine, alone reducing its susceptibility two to threefolds. The main aim of this study was to determine the dynamics of E138 mutation in the RT domain of the HIV-1 pol gene; in 6398 newly diagnosed and treatment-naive individuals in Turkey from 2013 to 2021. Rilpivirine-associated mutations were found among 424 (6.6%) out of 6398. Individuals with the E138 mutation had significantly higher HIV-1 RNA load than individuals without the E138 mutation (p = .044). The E138 mutation was mainly observed in the B subtype (40%) of HIV-1 compared to the non-B subtypes (26.9%) and the circulating recombinant forms (33.1%) (p < .001). Most E138 mutations were E138A (80%), followed by E138G (16.5%). This study uncovered the dynamics of rilpivirine-associated mutations over a long period and a large patient population. Before administering ART regimens consisting of rilpivirine, resistance monitoring is highly recommended for effective patient management in the treatment-of naive HIV-1-infected individuals.

Investigation of Brucella canis and Brucella abortus Seropositivity by In-House Rapid Slide Agglutination Test and In-House ELISA in Northern Cyprus.

The incidence of Brucella canis (B. canis) in humans is unknown in Northern Cyprus. In this study, we investigated the prevalence of B. canis and Brucella abortus (B. abortus) infection in human sera and evaluated the results obtained by agglutination-based techniques using standardized antigens made from B. canis comparatively. All of the subjects were negative in terms of Rose-Bengal plate test. Undiluted serum samples were initially screened by rapid slide agglutination test (RSAT), and those which were found positive were retested in the dilution of 1/25-1/200. Confirmation of the positive results was performed by using 2-mercaptoethanol standard agglutination test (SAT). The test antigen was prepared from the less mucoid M (-) variant of B. canis, and 1/1,048 titered dog antiserum was used as positive control. In 225 serum samples, 3.6% (8/225) was positive by B. canis M (-) RSAT, 4.4 % (10/225) was positive by B. canis M (-) indirect enzyme-linked immunosorbent assay (iELISA). 5.3% (12/225) was positive by B. abortus S99 RSAT and 9.8% (22/225) was positive by B. abortus S99 iELISA. Nine samples were positive by both B. abortus S99 RSAT and B. abortus S99 iELISA. Seven samples were positive by both B. canis M (-) RSAT and B. canis M (-) iELISA. One patient was positive by all methods. It is important to evaluate patient samples with RSAT and iELISA. Until the notification system gives better results to the Ministry of Health, in order to reach the real data for Northern Cyprus, multicenter prevalence determination studies should be done for future.

Fuzzy-Based PROMETHEE Method for Performance Ranking of SARS-CoV-2 IgM Antibody Tests.

Antibody tests, widely used as a complementary approach to reverse transcriptase-polymerase chain reaction testing in identifying COVID-19 cases, are used to measure antibodies developed for COVID-19. This study aimed to evaluate the different parameters of the FDA-authorized SARS-CoV-2 IgM antibody tests and to rank them according to their performance levels. In the study, we involved 27 antibody tests, and the analyzes were performed using the fuzzy preference ranking organization method for the enrichment evaluation model, a multi-criteria decision-making model. While criteria such as analytical sensitivity, specificity, positive predictive value, and negative predictive value were evaluated in the study, the ranking was reported by determining the importance levels of the criteria. According to our evaluation, Innovita 2019-nCoV Ab Test (colloidal gold) was at the top of the ranking. While Cellex qSARS-CoV-2 IgG/IgM Rapid Test and Assure COVID-19 IgG/IgM Rapid Tester ranked second and third on the list, the InBios-SCoV 2 Detect Ig M ELISA Rapid Test Kit was determined as the least preferable. The fuzzy preference ranking organization method for enrichment evaluation, which has been applied to many fields, can help decision-makers choose the appropriate antibody test for managing COVID-19 in controlling the global pandemic.

Investigation of SARS-CoV-2 Variants and Their Effect on SARS-CoV-2 Monoclonal Antibodies, Convalescent and Vaccine Plasma by a Novel Web Tool.

(1) Background: SARS-CoV-2 variants possess specific mutations throughout their genome; however, the effect of these mutations on pathogenesis is little known. The study aimed to identify SARS-CoV-2 variants and their susceptibility rate against monoclonal antibodies, convalescent, and vaccine plasma. (2) Methods: Strains isolated from COVID-19 cases in Turkey in April and September 2021 were involved. Illuma Nextera XT was processed for NGS, followed by virtual phenotyping (Coronavirus Antiviral and Resistance Database (CoV-RDB) by Stanford University). (3) Results: Among 211 strains, 79% were SARS-CoV-2 variants. B.1.1.7 (Alpha) was the most dominant, followed by B.1.617.2 (Delta), B.1.351 (Beta), and B.1.525 (Eta). Alpha and Delta were less susceptible to Etesevimab-Sotrovimab and Bamlanivimab-Etesevimab, respectively. Reduced efficacy was observed for convalescent plasma in Beta and Delta; AstraZeneca, Comirnaty plus AstraZeneca in Alpha; Comirnaty, Moderna, Novovax in Beta; Comirnaty in Delta. (4) Conclusion: CoV-RDB analysis is an efficient, rapid, and helpful web tool for SARS-CoV-2 variant detection and susceptibility analysis.

Circulating Dynamics of SARS-CoV-2 Variants between April 2021 and February 2022 in Turkey.

The diagnosis of new variants and monitoring their potential effects on diagnosis, therapeutics, and vaccines by genomic sequencing is essential to manage global public crises. In the current study, spike-genome next-generation sequencing was generated from 492 SARS-CoV-2 isolates to evaluate the mutations in Turkey from April 2021 to February 2022. The variant analysis was performed using (Coronavirus Antiviral and Resistance Database (CoV-RDB) by Stanford University). We revealed that the lineages Alpha (B.1.1.7), Beta (B.1.351), Delta (B.1.617.2), Eta (B.1.525), variant of interest (VOI), lota (B.1.526), Zeta (P.2), Omicron (B.1.1.529), and Omicron BA.1 (B.1.1.529.1) were in the circulation in Turkey during the given period. The most common lineages were B.1.1.7, B.1.617.2, B.1.1.529, and B.1.1.529.1 SARS-CoV-2 variant circulation in Turkey seems highly heterogenetic; however, quite similar to the global epidemiologic analysis. The existence of globally circulating variants in the same chronological order in Turkey can be a guide for precautions, treatment, and vaccine options to be taken in the future.

CCR5-Δ32 gene variant frequency in the Nigerian and Zimbabwean populations living in North Cyprus.

Background: The cystine-cystine chemokine receptor 5 (CCR5) is the primary HIV co-receptor involved in the viral entry process into human cells. The 32 bp deletion variant within the CCR5 gene (CCR5-Δ32) plays a very important role in viral recognition and progression of AIDS. Objective: The current study was aimed at evaluating the CCR5-Δ32 gene variation frequency in Nigerian and Zimbabwean populations residing in Northern Cyprus. Methods: A total number of 211 subjects (103 Nigerians and 108 Zimbabweans) were analyzed. Nigerian population was further analyzed with respect to the three major ethnicities: Igbo, Hausa, and Yoruba. Polymerase Chain Reaction was used to determine the CCR5-Δ32 gene variant status. Results: All studied subjects from both sampling groups were homozygous for the CCR5 wild type gene (CCR5-wt), meaning neither heterozygous nor homozygous genotypes of CCR5-Δ32 gene variant were observed. Conclusion: This study observed the absence of CCR5-Δ32 deletion gene in the Nigeria and Zimbabwean populations living in Northern Cyprus. These populations lack the genetic advantage over HIV infection and may also show a rapid progression towards AIDS. Additionally, these populations could impact the local gene frequency as these two populations interact more and more.

Analysis of ACE2 and TMPRSS2 coding variants as a risk factor for SARS-CoV-2 from 946 whole-exome sequencing data in the Turkish population.

Heterogeneity in symptoms associated with COVID-19 in infected patients remains unclear. ACE2 and TMPRSS2 gene variants are considered possible risk factors for COVID-19. In this study, a retrospective comparative genome analysis of the ACE2 and TMPRSS2 variants from 946 whole-exome sequencing data was conducted. Allele frequencies of all variants were calculated and filtered to remove variants with allele frequencies lower than 0.003 and to prioritize functional coding variants. The majority of detected variants were intronic, only two ACE2 and three TMPRSS2 nonsynonymous variants were detected in the analyzed cohort. The main ACE2 variants that putatively have a protective or susceptibility effect on SARS-CoV-2 have not yet been determined in the Turkish population. The Turkish genetic makeup likely lacks any ACE2 variant that increases susceptibility to SARS-CoV-2 infection. TMPRSS2 rs75603675 and rs12329760 variants that were previously defined as common variants that have different allele frequencies among populations and may have a role in SARS-CoV-2 attachment to host cells were determined in the population. Overall, these data will contribute to the formation of a national variation database and may also contribute to further studies of ACE2 and TMPRSS2 in the Turkish population and differences in SARS-CoV-2 infection among other populations.

Detection of SARS-CoV-2 N501Y mutation among SARS-CoV-2 variants of concern circulating in Northern Cyprus.

Aim: SARS-CoV-2 variants of concern (VOCs) carry signature mutations particularly in the spike protein. Most VOCs lineages that carry N501Y substitution have been reported to evade viral diagnostic tests and have impact on vaccine effectiveness. Therefore, monitoring the circulating variants represents a major requirement for a public health response worldwide. We aimed to investigate the prevalence of N501Y bearing SARS-CoV-2 samples in Northern Cyprus. Materials & methods: Reverse transcription quantitative PCR technique was used to identify N501Y mutation from 658 samples. Results: Our results indicate that the proportion of N501Y-bearing lineages increased significantly from January through May 2021 (45.2-75.5%) in the region. Conclusion: These results indicate that VOCs are dominant lineages in the country and highlight an alarming situation which require strict governmental measures to minimize COVID-19 morbidity and mortality.

Characteristics of hepatitis C virus resistance in an international cohort after a decade of direct-acting antivirals.

Background & Aims: Direct-acting antiviral (DAA) regimens provide a cure in >95% of patients with chronic HCV infection. However, in some patients in whom therapy fails, resistance-associated substitutions (RASs) can develop, limiting retreatment options and risking onward resistant virus transmission. In this study, we evaluated RAS prevalence and distribution, including novel NS5A RASs and clinical factors associated with RAS selection, among patients who experienced DAA treatment failure. Methods: SHARED is an international consortium of clinicians and scientists studying HCV drug resistance. HCV sequence linked metadata from 3,355 patients were collected from 22 countries. NS3, NS5A, and NS5B RASs in virologic failures, including novel NS5A substitutions, were examined. Associations of clinical and demographic characteristics with RAS selection were investigated. Results: The frequency of RASs increased from its natural prevalence following DAA exposure: 37% to 60% in NS3, 29% to 80% in NS5A, 15% to 22% in NS5B for sofosbuvir, and 24% to 37% in NS5B for dasabuvir. Among 730 virologic failures, most were treated with first-generation DAAs, 94% had drug resistance in ≥1 DAA class: 31% single-class resistance, 42% dual-class resistance (predominantly against protease and NS5A inhibitors), and 21% triple-class resistance. Distinct patterns containing ≥2 highly resistant RASs were common. New potential NS5A RASs and adaptive changes were identified in genotypes 1a, 3, and 4. Following DAA failure, RAS selection was more frequent in older people with cirrhosis and those infected with genotypes 1b and 4. Conclusions: Drug resistance in HCV is frequent after DAA treatment failure. Previously unrecognized substitutions continue to emerge and remain uncharacterized. Lay summary: Although direct-acting antiviral medications effectively cure hepatitis C in most patients, sometimes treatment selects for resistant viruses, causing antiviral drugs to be either ineffective or only partially effective. Multidrug resistance is common in patients for whom DAA treatment fails. Older patients and patients with advanced liver diseases are more likely to select drug-resistant viruses. Collective efforts from international communities and governments are needed to develop an optimal approach to managing drug resistance and preventing the transmission of resistant viruses.

The pediatric asymptomatic SARS-CoV-2 IgG seropositivity in the Turkish Republic of Northern Cyprus.

BACKGROUND: While children were initially thought to have serious contributions to the coronavirus disease 2019 (COVID-19) transmission, recent studies suggest otherwise. However, the possible effect of asymptomatic pediatric spread still has not yet received enough attention. The aim of our study was to estimate asymptomatic infection rates among children in the Turkish Republic of Northern Cyprus, by using pediatric patients admitted to a university hospital without any COVID-19-associated symptoms. METHODS: Blood samples collected from 80 pediatric patients with no symptoms and history of COVID-19 infection, who were admitted to a university hospital between September 2020 and January 2021, were included in the retrospective study. Isolated serum samples were tested by Dia.Pro SARS-CoV-2 IgG ELISA assays. RESULTS: The patient group included 40 (50%) male and 40 (50%) female patients. The average age of children was 7.6 ± 4.0 years, with min-max ages ranging from 2 to 15 years. Among the 80 patients tested, only one (1.3%) was detected positive by the Dia.Pro IgG ELISA kit. CONCLUSIONS: The asymptomatic seropositivity reported in our study suggests the use of randomly performed serologic tests to monitor SARS-CoV-2 infection among the pediatric population in schools that would contribute to the public health fight against COVID-19.

Integrase Strand Transfer Inhibitor (INSTI) Genotypic Resistance Analysis in Treatment-Naive, INSTI Free Antiretroviral-Experienced and INSTI-Experienced Turkish Patients Infected with HIV-1.

BACKGROUND AND OBJECTIVE: Integrase strand transfer inhibitors (INSTIs) are currently the standard of practice for first-line HIV therapy for most patients. We evaluated the mutations associated with INSTI resistance in naive HIV-1 infected patients and treated them with antiretrovirals (ART). METHODS: The study, conducted in the 2018 - 2020 period, included 50 ART-naïve patients, 69 INSTI free ART-experienced patients, and 82 INSTI-experienced patients. INSTI resistance mutations were interpreted using the Stanford University HIVdb Program algorithm. RESULTS: INSTI resistance was not detected in ART naïve patients. At least one INSTI resistance mutation was detected in 10% of the INSTI-free patients and 29% of the INSTI-treated patients. Major INSTI-mutations E138K, Y143R, S147G, Q148R, N155H, and E157Q were found in raltegravir. Additional mutations, E92Q, E138K, G140A, S147G, and Q148R were found in elvitegravir; E192Q, E138K/T, G140A/S, S147G, Q148H/R, N155H, E157Q were found in dolutegravir (DTG) experienced patients. According to all drug classes, drug resistance mutation prevalences were determined at the rate of 60%, 46%, and 46% in the RAL, EVG, and DTG groups, respectively. CONCLUSION: Our findings provide data for treatment and resistance management of INSTIs and may provide feedback for INSTIs resistance surveillance consensus-building efforts. In viral rebound under INSTI treatment, INSTI-resistant mutations follow typical INSTI resistance pathways and high resistance rates. INSTI resistance genotypic analysis should be considered before any DTG-based regimes can be initiated in the future, and reduced DTG susceptibility should be carefully monitored and investigated.

Positive Anti-HIV ELISA Results in Pregnancy: Is It Reliable?

BACKGROUND: Human immunodeficiency virus (HIV) can be transmitted from mothers to their babies during pregnancy, delivery through vaginal fluids or breastfeeding. As false positivity anti-HIV results due to pregnancy could be detected and no relevant study have been reported in Northern Cyprus so far, we aimed to estimate the false anti-HIV positivity rate in pregnant women. METHODS: A total of 11.977 women admitted to Near East University Hospital between 2015 and 2018 were involved. The fourth generation anti-HIV-1/2 ELISA test was carried out by chemiluminescence enzyme immunoassay. Positive results were confirmed by real-time polymerase chain reaction (rt-PCR). SPSS (Statistical Package for the Social Sciences) Demo Ver 22 program was used for statistical analysis and significance (p<0.05) was measured by Person Chi-Square and Fisher's Exact tests. RESULTS: Anti-HIV-1/2 ELISA test was positive in 7 (0.3%) of pregnant and 11 (0.1%) of non-pregnant women. HIV RNA was not detected in any pregnant however, was detected in 2 (0.02%) of non pregnant. S/Co titer of pregnant and non pregnant who have positive anti-HIV-test without viral load was x̄=2.68±1.64 (1.34-5.20) and x̄=8.63±7.68 (1.56-20.98) respectively. False positivity was significantly higher in pregnants compared to non-pregnants (p=0.033). CONCLUSION: False positivity can be encountered during pregnancy therefore, positive anti-HIV-1/2 ELISA results should be confirmed with molecular techniques before initiating antiretroviral treatment.

Variant analysis of SARS-CoV-2 strains with phylogenetic analysis and the Coronavirus Antiviral and Resistance Database.

Aims: This study determined SARS-CoV-2 variations by phylogenetic and virtual phenotyping analyses. Materials & methods: Strains isolated from 143 COVID-19 cases in Turkey in April 2021 were assessed. Illumina NexteraXT library preparation kits were processed for next-generation ]sequencing. Phylogenetic (neighbor-joining method) and virtual phenotyping analyses (Coronavirus Antiviral and Resistance Database [CoV-RDB] by Stanford University) were used for variant analysis. Results: B.1.1.7-1/2 (n = 103, 72%), B.1.351 (n = 5, 3%) and B.1.525 (n = 1, 1%) were identified among 109 SARS-CoV-2 variations by phylogenetic analysis and B.1.1.7 (n = 95, 66%), B.1.351 (n = 5, 4%), B.1.617 (n = 4, 3%), B.1.525 (n = 2, 1.4%), B.1.526-1 (n = 1, 0.6%) and missense mutations (n = 15, 10%) were reported by CoV-RDB. The two methods were 85% compatible and B.1.1.7 (alpha) was the most frequent SARS-CoV-2 variation in Turkey in April 2021. Conclusion: The Stanford CoV-RDB analysis method appears useful for SARS-CoV-2 lineage surveillance.

Variable Proportions of Phylogenetic Clustering and Low Levels of Antiviral Drug Resistance among the Major HBV Sub-Genotypes in the Middle East and North Africa.

Hepatitis B virus (HBV) infection remains a major public health threat in the Middle East and North Africa (MENA). Phylogenetic analysis of HBV can be helpful to study the putative transmission links and patterns of inter-country spread of the virus. The objectives of the current study were to analyze the HBV genotype/sub-genotype (SGT) distribution, reverse transcriptase (RT), and surface (S) gene mutations and to investigate the domestic transmission of HBV in the MENA. All HBV molecular sequences collected in the MENA were retrieved from GenBank as of 30 April 2021. Determination of genotypes/SGT, RT, and S mutations were based on the Geno2pheno (hbv) 2.0 online tool. For the most prevalent HBV SGTs, maximum likelihood phylogenetic analysis was conducted to identify the putative phylogenetic clusters, with approximate Shimodaira-Hasegawa-like likelihood ratio test values ≥ 0.90, and genetic distance cut-off values ≤ 0.025 substitutions/site as implemented in Cluster Picker. The total number of HBV sequences used for genotype/SGT determination was 4352 that represented a total of 20 MENA countries, with a majority from Iran (n = 2103, 48.3%), Saudi Arabia (n = 503, 11.6%), Tunisia (n = 395, 9.1%), and Turkey (n = 267, 6.1%). Genotype D dominated infections in the MENA (86.6%), followed by genotype A (4.1%), with SGT D1 as the most common in 14 MENA countries and SGT D7 dominance in the Maghreb. The highest prevalence of antiviral drug resistance was observed against lamivudine (4.5%) and telbivudine (4.3%). The proportion of domestic phylogenetic clustering was the highest for SGT D7 (61.9%), followed by SGT D2 (28.2%) and genotype E (25.7%). The largest fraction of domestic clusters with evidence of inter-country spread within the MENA was seen in SGT D7 (81.3%). Small networks (containing 3-14 sequences) dominated among domestic phylogenetic clusters. Specific patterns of HBV genetic diversity were seen in the MENA with SGT D1 dominance in the Levant, Iran, and Turkey; SGT D7 dominance in the Maghreb; and extensive diversity in Saudi Arabia and Egypt. A low prevalence of lamivudine, telbivudine, and entecavir drug resistance was observed in the region, with almost an absence of resistance to tenofovir and adefovir. Variable proportions of phylogenetic clustering indicated prominent domestic transmission of SGT D7 (particularly in the Maghreb) and relatively high levels of virus mobility in SGT D1.

Genetic characterisation of antibiotic resistance transposons Tn6608 and Tn6609 isolated from clinical Pseudomonas strains in Cyprus.

OBJECTIVES: Antibiotic therapy for Pseudomonas infections is becoming increasingly difficult. In this study, the transposons from two multidrug-resistant (MDR) clinical Pseudomonas strains containing related transposons responsible for giving rise to resistance determinants were characterised. METHODS: Two MDR clinical Pseudomonas isolates were obtained from a medical facility in Cyprus. The strains were identified as Pseudomonas putida C54 and Pseudomonas aeruginosa C69. DNA was extracted from both strains and was sequenced. Transposons were identified, annotated and compared with DNA sequences in GenBank. RESULTS: Two related nested transposons, here named Tn6608 (from P. putida C54) and Tn6609 (from P. aeruginosa C69), were characterised. The transposons are built on an ancestral Tn1403 base element (here named Tn1403A) that contains only the transposition module (tnpA and tnpR) and the associated cargo gene module (orfA, orfB, orfC and orfD) flanked by a 38-bp inverted repeat. The nested transposons identified in this study have evolved via acquisition of multiple transposons, adding multiple resistance genes to an ancestral transposon that originally lacked any resistance determinants. CONCLUSION: Transposons related to Tn6608 and Tn6609 have evolved and are globally disseminated. Of particular interest is that most of these nested transposons are located within the same site in a genomic island, providing alternative avenues for dissemination.