Antiviral drug resistance in herpes simplex virus 1 and 2 (HSV-1 & 2) is a significant clinical challenge, particularly in immunocompromised patients. Drug susceptibility testing (DST) aids clinical management and can be conducted through genotypic (partial genome sequencing) or phenotypic (cell culture) methods. Both have inherent limitations: genotypic DST is limited by outdated datasets lacking information on new helicase-primase inhibitors and corresponding phenotypic data as well as sparse clinical correlations. Phenotypic DST is mainly hampered by a lack of standardization and timely results.

To compile an up-to-date and comprehensive HSV drug resistance dataset encompassing all reported drug resistance-associated mutations (DRMs), polymorphisms, and viral phenotypes. To aggregate clinical conditions with available DST data.

A PubMed search identified studies (January 2016-September 2024) on DRMs associated with resistance to aciclovir, penciclovir, brivudine, foscarnet, cidofovir, amenamevir, and pritelivir. Data from a previous HSV resistance dataset (pre-2016) were also included.

In this review, we summarize novel mutations in the thymidine kinase, polymerase, and helicase-primase gene of HSV conferring resistance to antiviral drugs. Clinical information was available for 513 mutations. In 90% of these (461 cases), viral phenotype and clinical assessment were congruent. However, 10% of cases not responding to antiviral therapy showed phenotypically susceptible virus isolates. We present a framework for clinical and diagnostic management of cases with drug resistant HSV infection.

This dataset paves the way to harmonize reporting of DRMs for diagnostic labs and to accelerate genotypic DST interpretation through aggregated data. Ongoing large-scale data collection of genotypic, phenotypic, and clinical data is crucial for evidence-based management of HSV antiviral resistance and clinical guidelines.

The emergence of drug resistance in the human immunodeficiency virus (HIV) remains a formidable challenge to the long-term efficacy of antiretroviral therapy (ART). A growing body of evidence highlights the critical role of epistasis, the dependence of mutational effects on the sequence context, in shaping the fitness landscape of HIV under ART-induced selection pressure. However, the biophysical origins of the epistatic interactions involved in engendering drug-resistance mutations (DRMs) remain unclear. Are the mutational correlations "intrinsic" to the properties of the protein, or do they arise because of drug binding? We use a Potts sequence-covariation statistical energy model built on patient-derived HIV-1 protein sequences to construct computational double mutant cycles that probe pairwise epistasis for all observed mutations across the three major HIV drug-target enzymes. We find that the strongest epistatic effects occur between mutations at residue positions that frequently mutate during the course of ART, termed resistance-associated positions. To investigate the structural origins of the strongest epistatic interactions, we perform ∼100 free energy perturbation molecular dynamics simulations, revealing that the primary contribution to the pairwise epistasis between DRMs arises from cooperative effects on protein stability and folding as an intrinsic consequence of the protein mutational landscape. The results collectively reinforce a mechanism of resistance evolution whereby viruses escape drug pressure by selectively engendering mutations at "intrinsically" coupled sites, allowing them to cooperatively ameliorate fitness detriments incurred by individual DRMs.

Epistasis refers to the phenomenon where the effect of a mutation on protein structure and function is dependent on the genetic sequence background of the mutation, resulting in the combined effect of mutations being non-additive. Epistasis plays a significant role in the evolution of drug resistance in viruses such as HIV under therapeutic selection pressure. We combine a protein sequence coevolutionary model and molecular dynamics free energy simulations to identify and probe the mechanistic origins of the strongest epistatic interactions connecting HIV drug-resistance mutations. The work establishes a foundation to probe the molecular bases of epistasis and predict the evolution of resistance predicated on the knowledge of epistatic interaction networks.

Lenacapavir, a novel HIV-1 capsid inhibitor, shows promise for treating MDR HIV-1, as well as for pre-exposure prophylaxis (PrEP) in prevention of HIV infection. Its unique mechanism and lack of cross-resistance with other antiretroviral classes make lenacapavir a significant addition to HIV therapy. The clinical trials CALIBRATE and CAPELLA have demonstrated high viral suppression rates in both ART-naive individuals and individuals with MDR HIV-1. Lenacapavir-associated resistance mutations, such as M66I and Q67H, rarely seen as natural polymorphisms in lenacapavir-naive populations, are predominantly studied in subtype B HIV-1.

Our study aimed to investigate the prevalence of lenacapavir resistance-associated mutations in HIV-1 subtypes A1 and D in a cohort of individuals living with HIV-1 from southwestern Uganda.

Utilizing plasma samples from ART-naive adults living in Uganda, HIV-1 Gag p24 (capsid) sequences were analysed for lenacapavir resistance mutations.

Among 546 lenacapavir-naive participants, no major lenacapavir resistance-associated mutations were found. Minor mutations were present in 1.6% of participants, with T107A being the most common. Longitudinal data indicated the persistence of T107A for at least 3 years post-ART initiation in one participant. Phylogenetic analysis indicated individuals carrying T107A were found independently in distinct locations within the tree, suggesting that T107A might have arisen from multiple distinct base substitution events. Shannon entropy analysis showed high variability in certain capsid sites, but none overlapped with known lenacapavir resistance sites.

These findings suggest a low prevalence of naturally occurring lenacapavir resistance mutations in Uganda, supporting lenacapavir's potential efficacy in this region.

The recent pandemics of viral diseases, COVID-19/mpox (humans) and lumpy skin disease (cattle), have kept us glued to viral research. These pandemics along with the recent human metapneumovirus outbreak have exposed the urgency for early diagnosis of viral infections, vaccine development, and discovery of novel antiviral drugs and therapeutics. To support this, there is an armamentarium of virus-specific computational tools that are currently available. VITALdb (VIroinformatics Tools and ALgorithms database) is a resource of ~360 viroinformatics tools encompassing all major viruses (SARS-CoV-2, influenza virus, human immunodeficiency virus, papillomavirus, herpes simplex virus, hepatitis virus, dengue virus, Ebola virus, Zika virus, etc.) and several diverse applications [structural and functional annotation, antiviral peptides development, subspecies characterization, recognition of viral recombination, inhibitors identification, phylogenetic analysis, virus-host prediction, viral metagenomics, detection of mutation(s), primer designing, etc.]. Resources, tools, and other utilities mentioned in this article will not only facilitate further developments in the realm of viroinformatics but also provide tremendous fillip to translate fundamental knowledge into applied research. Most importantly, VITALdb is an inevitable tool for selecting the best tool(s) to carry out a desired task and hence will prove to be a vital database (VITALdb) for the scientific community. Database URL: https://compbio.iitr.ac.in/vitaldb.

The emergence of drug-resistant mutations in human immunodeficiency virus (HIV) over time presents a challenge to treatment. We describe the development of drug-resistance mutations and ART efficacy reduction in Vietnamese patients with failure of first-line ART during a 5-year period.

This is a 5-year observational cohort study with HIV viral loads of patients evaluated annually for 5 years (2017-2022) at the hospitals in Vietnam. Patients with a viral load ≥ 1000 copies/mL were subjected to identifying mutations in reverse transcriptase, protease, and integrase to evaluate HIV resistance and the efficacy of ART.

After 5 years of monitoring the HIV load of 2932 patients on ART, 75 (2.56%) patients had concurrent virological failure at all 5 years. In 2017, only 2/75 HIV strains possessed Protease Inhibitor (PI) resistance mutations, while 75/75 HIV strains had both Nucleoside Reverse Transcriptase Inhibitors (NRTIs) and Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) resistance mutations. Only four PI resistance variants were found, while 40 and 32 mutations were resistant to NRTIs and NNRTIs. After 5 years, the number of HIV PI resistance mutations had increased to 14, with 13 new mutations emerging. There were six novel mutations associated with resistance to NRTIs, NNRTIs, and the proportion of preexisting mutations increased from 1.3% to 13.3%. Furthermore, HIV sensitivity to ART decreased from 2.7% to 18.6%.

After 5 years, HIV had increased resistance mutations to PIs, NRTIs, and NNRTIs, with PI resistance mutations increasing the most rapidly, and the decrease in HIV sensitivity to PIs was higher than that to NRTIs and NNRTIs.

HIV continues to be a significant global public health concern. In 2022, an estimated 29.8 million people living with HIV received antiretroviral treatment (ART). From this, an estimated 10-15% of individuals living with HIV have drug-resistant strains of the virus. Testing for resistance to antiretroviral drugs is recommended before initiating ART. However, such services are often inaccessible due to costs and the need for complex laboratory infrastructure. The assessment of HIV drug resistance (HIVDR) relies on genotyping sequencing and algorithms to interpret genotypic resistance test results. Genotypic assays involve Sanger sequencing of the reverse transcriptase (RT), protease (PR) and integrase (IN) genes of circulating RNA in plasma to detect mutations that are known to confer drug resistance. While state-of-the-art sequencing technologies have swept the globe and enhanced our global pandemic response capabilities, they are still sparingly used for HIVDR surveillance. The scale-up of ART, especially in low- and middle-income countries, necessitates the establishment of cheap, expeditious and decentralized methods for HIVDR monitoring. Here, we outline how one low-capital next-generation sequencing platform, namely, nanopore sequencing, could augment efforts in expanding HIVDR surveillance efforts, especially in resource-limited settings. We discuss that because of its versatility, nanopore sequencing can accelerate HIVDR surveillance in conjunction with scaling up ART efforts and outline some of the challenges that need to be considered before its widespread and routine adaptation to detect drug resistance rapidly.

The presentation of HIV peptides by the human leukocyte antigen (HLA) complex to CD8+ cytotoxic T-cells (CTLs) is critical to limit viral pathogenesis. HIV can mutate to evade HLA-restricted CTL responses and resist antiretroviral drugs, raising questions about how it balances these evolutionary pressures. Here, we used a computational approach to assess how drug resistance-associated mutations (RAMs) affect the binding of HIV-1 subtype B or C peptides to the most prevalent HLA alleles in US, European, and South African populations. We predict RAMs that may be favored in certain populations and report the under-representation of Y181C in people expressing HLA-B*57:01. This finding agreed with our computational predictions when Y181C was at the major anchor site P2, suggesting the potential relevance of our approach. Overall, our findings lay out a conceptual framework to study the implications of HLA alleles on the emergence of HIV RAMs at the individual and population levels.

Dolutegravir (DTG) + lamivudine (3TC) demonstrated high rates of virologic suppression (VS) and low rates of virologic failure (VF), discontinuation, and drug resistance in randomized trials. Real-world evidence can support treatment effectiveness, safety, and tolerability in clinical practice and aid in treatment decisions.

A systematic literature review (SLR) was conducted to identify studies using DTG + 3TC (January 2013-March 2024). Studies were screened to include observational studies reporting 48- or 96-week on-treatment VS, VF, or discontinuation outcomes; proportions of individuals with each outcome at each time point were estimated using random- and common-effects models.

Of 249 SLR-identified publications, 43 reported consistently defined outcomes of interest at comparable time points, representing 1480 individuals naive to antiretroviral therapy (ART) and 12,234 individuals with prior ART experience. At weeks 48 and 96, respectively, estimated proportions (95% CIs; random-effects model) with on-treatment VS were high (naive to ART, 0.964 [0.945-0.979] and 0.902 [0.816-0.966]; prior ART, 0.966 [0.950-0.980] and 0.971 [0.946-0.990]), with low estimated proportions experiencing VF (naive to ART, 0.001 [0.000-0.013] and 0.001 [0.000-0.008]; prior ART, 0.009 [0.005-0.015] and 0.015 [0.007-0.024]) and discontinuations for any reason (naive to ART, 0.052 [0.019-0.097] and 0.130 [0.084-0.183]; prior ART, 0.067 [0.042-0.098] and 0.084 [0.047-0.130]). Across identified studies (> 44,000 unique individuals), those reporting resistance outcomes at VF/blip (regardless of emergence) detected integrase strand transfer inhibitor (INSTI) mutations in 0 of 2346 individuals naive to ART and 0.02% (4/20,060) of individuals with prior ART experience (S147G, R263K, G118R + E138K, T66A + G118R + E138K); additionally, N155H was reported in an individual using DTG + 3TC with unknown baseline ART status.

Overall treatment outcomes in real-world settings confirm the efficacy, tolerability, and high barrier to resistance seen in phase 3 trials across diverse populations, including those naive to ART or with prior ART experience.

Characterizing HIV clustering rates and their trends over time can improve understanding a local epidemic and enhance its control.

Leveraging an academic-public health partnership in Rhode Island, we explored longitudinal dynamics of statewide clustering rates among key populations from 1991 to 2023. Partial HIV-1 pol sequences were grouped by year of HIV-1 diagnosis. Molecular clusters were identified in cumulative annual phylogenies. Overall clustering rates, and clustering rates of newly diagnosed and prevalent infections, and of specific sociodemographic characteristics of key populations over time were determined. Mann-Kendall statistics were used to estimate clustering rate trends and relationships among groups.

By the end of 2023, 2630 individuals with sequences represented the statewide epidemic in Rhode Island. Overall clustering rates increased from 7% in 1991 to 46% in 2023, correlating with cumulative sequence increase. Clustering rates of newly diagnosed and prevalent infections significantly increased over time, higher in newly diagnosed individuals since the early 2000s. Increases were also observed among groups defined by gender, age, transmission risks, race, mental illness, HIV-1 subtypes, and country of birth, with some crossovers and divergence patterns over time.

Exploring dynamics of HIV clustering rates over three decades in a statewide HIV-1 epidemic expanded its characterization and provided insight into its evolving changes. These dynamics may indicate a gradual shift towards a more concentrated and localized HIV-1 epidemic, highlighting important opportunities for targeted interventions to effectively prevent new HIV transmissions.

To examine if point-of-care (POC) urine tenofovir testing-informed counseling could be used to improve virologic suppression (VS) among participants with virologic failure (VF) after ≥1 prior round of enhanced adherence counseling (EAC).

Participants were enrolled from 42 clinics across Namibia. At each monthly medication pick-up, participants completed the POC urine test and received EAC informed by this testing (EAC+). If VS was not achieved after 3 months of EAC+, up to 3 additional rounds of EAC+ were provided, with resistance testing at month (M)9.

Of 310 potentially eligible participants across 42 clinics in Namibia, we enrolled 211 participants with VF (median age 33 years, 61% female); 195 reached M3 defined as receiving EAC+ and follow-up viral load testing; 169 achieved VS within M3 (87%, P < 0.001) and 97% by M9 (181/186) compared to 40% (22/55) prior to the intervention (P < 0.001). Resistance testing was performed in five remaining participants with VF at M9, of whom 1/5 (20%) developed dolutegravir resistance.

The urine tenofovir assay when incorporated into adherence counseling has potential to be a cost-effective intervention among participants failing tenofovir-based regimens, increasing VS to 97% in those failing Tenofovir-Lamivudine-Dolutegravir. Encouraging results of this pre-post intervention will be rigorously tested in a randomized trial.

Background/Objectives: The development of HIV drug resistance to current antiretrovirals, and the antiretrovirals' inability to cure HIV, provides the need of developing novel drugs that inhibit HIV-1 subtypes and drug-resistance strains. Fungal endophytes, including Alternaria alternata, stand out for their potentially antiviral secondary metabolites. Hence, this study investigates the anti-HIV activities and mechanism of action of the A. alternata crude extract against different HIV-1 subtypes and integrase-resistant mutant strains. Methods: Cytotoxicity of the A. alternata crude extract on TZM-bl cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed. The crude extract antiviral activity against subtypes A, B, C, and D and integrase drug-resistant strain T66K and S230R was determined using a luciferase-based antiviral assay. Luciferase and p24 ELISA-based time-of-addition assays were used to determine the mechanism of action of the crude extract. Docking scores and protein ligand interactions of integrase T66K and S230R strains against the identified bioactive compounds were determined. Results: The crude extract CC50 was 300 μg/mL and not cytotoxic to the TZM-bl cell lines. In HIV-1 subtypes A, B, C, and D, the crude extract exhibited 100% inhibition and therapeutic potential. The A. alternata crude extract had strong anti-HIV-1 activity against integrase strand transfer drug-resistant strains T66K and S230R, with a 0.7265- and 0. 8751-fold increase in susceptibility. The crude extract had antiviral activity during attachment, reverse transcription, integration, and proteolysis. In silico calculations showed compounds 2,3-2H-Benzofuran-2-one, 3,3,4,6-tetramethyl-, 3-Methyl-1,4-diazabicyclo[4.3.0]nonan-2,5-dione, N-acetyl, Coumarin, 3,4-dihydro-4,5,7-trimethyl-, Cyclopropanecarboxamide, N-cycloheptyl, Pyrrolo[1,2-a]pyrazine-1,4-dione, and hexahydro-3-(2-methylpropyl)- crude extract bioactive compounds had strong docking scores and diverse binding mechanisms with integrase. Conclusions: The A. alternata crude extract demonstrates strong antiviral activity against different HIV-1 subtypes and integrase drug-resistance strains. The extract inhibited various stages of the HIV-1 life cycle. The bioactive compounds 2,3-2H-Benzofuran-2-one, 3,3,4,6-tetramethyl-, 3-Methyl-1,4-diazabicyclo[4.3.0]nonan-2,5-dione, N-acetyl, Coumarin, 3,4-dihydro-4,5,7-trimethyl-, Cyclopropanecarboxamide, N-cycloheptyl, Pyrrolo[1,2-a]pyrazine-1,4-dione, and hexahydro-3-(2-methylpropyl)- may be responsible for the antiviral activity of A. alternata.

The study assessed replicative human immunodeficiency virus-(HIV-) infection and replicative co-infections as well as molecular determinants of reduced susceptibility towards anti-retroviral therapy in a Ghanaian population of known HIV patients and a control group.

Real-time PCRs for HIV-1, HIV-2, hepatitis B virus (HBV) and hepatitis C virus (HCV) were run with serum samples from known Ghanaian HIV-patients (n = 975) and control individuals (n = 105). For 108 individuals, HIV-sequence analysis was performed.

Prevalence of replicative HIV-1 infection was 59.8% (583/975) in the known HIV-positive population and 2.9% (3/105) in the controls. Prevalences of replicative HBV-infection were comparable with 3.4% (33/975) in the HIV-positive individuals and 3.8% (4/105) in the controls. HIV-2 and HCV sequences were not recorded. Almost perfect concordance between two compared HIV-1-PCR assays was indicated by Fleiss' Kappa >0.8. Sanger sequencing indicated CRF_02AG, G and A3 as the quantitatively dominating HIV-1 subtypes, a minority of 3.4% CXCR4 tropism and high detection rates of mutations mediating reduced susceptibility towards nucleoside reverse transcriptase inhibitors (71.9%, 64/89), non-nucleoside reverse transcriptase inhibitors (95.5%, 85/89), protease inhibitors (95.9%, 93/97) and integrase inhibitors (22.4%, 22/98).

The assessment did not suggest HIV-triggered increased replication of HBV and HCV in the investigated Ghanaian population.

Islatravir (ISL) is the first-in-class nucleoside reverse transcriptase translocation inhibitor (NRTtI) with novel modes of action. Data on ISL resistance are currently limited, particularly to HIV-1 non-B subtypes. This study aimed to assess prevalent nucleos(t)ide reverse transcriptase inhibitor (NRTI)-resistant mutations in HIV-1 subtype C for their phenotypic resistance to ISL. Prevalent single and combinations of NRTI-resistant mutations were selected from a routine HIV-1 genotypic drug resistance testing database and introduced into HIV-1 subtype C-like pseudoviruses, which were then tested for ISL susceptibility. Single NRTI-resistant mutations were susceptible or showed only a low level of resistance to ISL. This included thymidine analogue mutations (TAMs, i.e., M41L, D67N, K70R, T215FY, and K219EQ) and non-TAMs (i.e., A62V, K65R, K70ET, L74IV, A114S, Y115F, and M184V). Combinations of M184V with one or more additional NRTI-resistant mutations generally displayed reduced ISL susceptibilities. This was more prominent for combinations that included M184V+TAMs, and particularly M184V+TAM-2 mutations. Combinations that included M184V+K65R did not impact significantly on ISL susceptibility. Our study suggests that ISL would be effective in treating people living with HIV (PLWH) failing tenofovir disoproxil fumarate (TDF)/lamivudine (3TC) or TDF/emtricitabine (FTC)-containing regimens, but would be less effective in PLH failing zidovudine (AZT) with 3TC or FTC-containing regimens.

A comprehensive and accessible Herpesvirus drug resistance database was designed to serve as an international reference for diagnosis and clinical studies. This database available at https://www.unilim.fr/cnr-herpesvirus/outils/codexmv/includes both resistance-related mutations and natural polymorphisms. Initially designed for human cytomegalovirus, it will be expanded to include herpes simplex and varicella-zoster viruses. Newly published mutations and new mutations reported by users or collaborating expert laboratories will be reviewed by an international committee of reference laboratories before inclusion in the database. Coupled with the Herpesvirus Sequence Analysis tool (HSA) mutation reports from NGS or Sanger sequences, it will be an open source for researchers in the field of Herpesviruses. We hope to fill this unmet need for the development and standardization of resistance genotyping.

Clinical studies have reported rising pre-treatment HIV drug resistance during antiretroviral treatment (ART) scale-up in Africa, but representative data are limited. We estimated population-level drug resistance trends during ART expansion in Uganda.

We analyzed data from the population-based open Rakai Community Cohort Study conducted at agrarian, trading, and fishing communities in southern Uganda between 2012 and 2019. Consenting participants aged 15-49 were HIV tested and completed questionnaires. Persons living with HIV (PLHIV) provided samples for viral load quantification and virus deep-sequencing. Sequence data were used to predict resistance. Population prevalence of class-specific resistance and resistance-conferring substitutions were estimated using robust log-Poisson regression.

Data from 93,622 participant-visits, including 4,702 deep-sequencing measurements, showed that the prevalence of NNRTI resistance among pre-treatment viremic PLHIV doubled between 2012 and 2017 (PR:1.98, 95%CI:1.34-2.91), rising to 9.61% (7.27-12.7%). The overall population prevalence of pre-treatment viremic NNRTI and NRTI resistance among all participants decreased during the same period, reaching 0.25% (0.18% - 0.33%) and 0.05% (0.02% - 0.10%), respectively (p-values for trend = 0.00015, 0.002), coincident with increasing treatment coverage and viral suppression. By the final survey, population prevalence of resistance contributed by treatment-experienced PLHIV exceeded that from pre-treatment PLHIV, with NNRTI resistance at 0.54% (0.44%-0.66%) and NRTI resistance at 0.42% (0.33%-0.53%). Overall, NNRTI and NRTI resistance was predominantly attributable to rtK103N and rtM184V. While 10.52% (7.97%-13.87%) and 9.95% (6.41%-15.43%) of viremic pre-treatment and treatment-experienced PLHIV harbored the inT97A mutation, no major dolutegravir resistance mutations were observed.

Despite rising NNRTI resistance among pre-treatment PLHIV, overall population prevalence of pre-treatment resistance decreased due to treatment uptake. Most NNRTI and NRTI resistance is now contributed by treatment-experienced PLHIV. The high prevalence of mutations conferring resistance to components of current first-line ART regimens among PLHIV with viremia is potentially concerning.

Doravirine (DOR) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) with efficacy against some NNRTI-resistant mutants. Although DOR resistance mutations are established for HIV-1 subtype B, it is less clear for non-B subtypes. This study investigated prevalent NNRTI resistance mutations on DOR susceptibility in HIV-1 subtype C. Prevalent drug resistance mutations were identified from a South African genotypic drug resistance testing database. Mutations, single or in combination, were introduced into replication-defective pseudoviruses and assessed for DOR susceptibility in vitro. The single V106M and Y188L mutations caused high-level resistance while others did not significantly impact DOR susceptibility. We observed an agreement between our in vitro and the Stanford HIVdb predicted susceptibilities. However, the F227L mutation was predicted to cause high-level DOR resistance but was susceptible in vitro. Combinations of mutations containing K103N, V106M or Y188L caused high-level resistance, in agreement with the predictions. These mutations are frequently observed in patients failing efavirenz- or nevirapine-based first-line regimens. However, they are also observed in those failing a protease inhibitor-based second-line regimen, as we have observed in our database. Genotypic drug resistance testing is therefore vital prior to the initiation of DOR-based treatment for those previously exposed to efavirenz or nevirapine.

The prevention and treatment of many herpesvirus associated diseases is based on the utilization of antiviral therapies, however therapeutic success is limited by the development of drug resistance. Currently no single database cataloguing resistance mutations exists, which hampers the use of sequence data for patient management. We therefore developed HerpesDRG, a drug resistance mutation database that incorporates all the known resistance genes and current treatment options, built from a systematic review of available genotype to phenotype literature. The database is released along with an R package that provides a simple approach to resistance variant annotation and clinical implication analysis from common sanger and next generation sequencing data. This represents the first openly available and community maintainable database of drug resistance mutations for the human herpesviruses (HHV), developed for the community of researchers and clinicians tackling HHV drug resistance.

The WHO currently recommends dolutegravir (DTG)-based ART for persons living with HIV infection in resource-limited-settings (RLS). To expand access to testing for HIV drug resistance (DR) to DTG in RLS, we developed probes for use in the oligonucleotide ligation assay (OLA)-Simple, a near-point of care HIV DR kit. Genotypic data from clinical trials and case reports were used to determine the mutations in HIV-1 integrase critical to identifying individuals with DTG-resistance at virologic failure of DTG-based ART. Probes to detect G118R, Q148H/K/R, N155H and R263K in HIV-1 subtypes A, B, C, D and CRF01_AE were designed using sequence alignments from the Los Alamos database and validated using 61 clinical samples of HIV-1 subtypes A, B, C, D, CRF01_AE genotyped by PacBio (n = 15) or Sanger (n = 46). Initial OLA probes failed to ligate for 16/244 (6.5%) codons (9 at G118R and 7 at Q148H/K/R). Probes revised to accommodate polymorphisms interfering with ligation at codons G118R and Q148R reduced indeterminates to 3.7% (5 at G118R and 4 at Q148H/K/R) and detected DTG-mutations with a sensitivity of 96.5% and 100% specificity. These OLA DTG resistance probes appear highly sensitive and specific across HIV-1 subtypes common in RLS with high burden of HIV infection.

The global prevalence of resistance to antiviral drugs combined with antiretroviral therapy (cART) emphasizes the need for continuous monitoring to better understand the dynamics of drug-resistant mutations to guide treatment optimization and patient management as well as check the spread of resistant viral strains. We have recently integrated next-generation sequencing (NGS) into routine HIV drug resistance (HIVDR) monitoring, with key challenges in the bioinformatic analysis and interpretation of the complex data generated, while ensuring data security and privacy for patient information. To address these challenges, here we present HIV-DRIVES (HIV Drug Resistance Identification, Variant Evaluation, and Surveillance), an NGS-HIVDR bioinformatics pipeline that has been developed and validated using Illumina short reads, FASTA, and Sanger ab1.seq files.

We developed the Healthy Families-PrEP intervention to support HIV-prevention during periconception and pregnancy. We evaluated preexposure prophylaxis (PrEP) use with three objective measures.

This single-arm intervention study enrolled women in KwaZulu-Natal, South Africa, who were HIV-uninfected, not pregnant, in a relationship with a partner with HIV or unknown-serostatus, and with pregnancy plans. PrEP was offered as part of a comprehensive HIV prevention intervention. Participants were followed for 12 months.

We evaluated periconception PrEP uptake and adherence using quarterly plasma tenofovir concentrations. We modeled factors associated with PrEP uptake and high plasma tenofovir (past day dosing). Patterns of use were analyzed using electronic pillcap data. Dried blood spots to measure intracellular tenofovir product (past 2 months dosing) were analyzed for a subset of women.

Three hundred thirty women with median age 24 (IQR: 22-27) years enrolled. Partner HIV-serostatus was unknown by 96% ( N  = 316); 60% (195) initiated PrEP. High plasma tenofovir concentrations were seen in 35, 25, 22, and 20% of samples at 3, 6, 9, and 12 months, respectively. Similar adherence was measured by pillcap and dried blood spots. In adjusted models, lower income, alcohol use, and higher HIV stigma were associated with high plasma tenofovir. Eleven HIV-seroconversions were observed (incidence rate: 4.04/100 person-years [95% confidence interval: 2.24-7.30]). None had detectable plasma tenofovir.

The Healthy Families-PrEP intervention supported women in PrEP use. We observed high interest in periconception PrEP and over one-third adhered to PrEP in the first quarter; one-fifth were adherent over a year. High HIV incidence highlights the importance of strategies to reduce HIV incidence among periconception women.

NCT03194308.

The human immunodeficiency virus type-1 epidemic in Pakistan has significantly increased over the last two decades. In Karachi, Pakistan, there is a lack of updated information on the complexity of HIV-1 genetic diversity and the burden of drug resistance mutations (DRMs) that can contribute to ART failure and poor treatment outcomes. This study aimed to determine HIV-1 genetic diversity and identify drug-resistance mutations among people living with HIV in Karachi. A total of 364 HIV-positive individuals, with a median age of 36 years, were enrolled in the study. The HIV-1 partial pol gene was successfully sequenced from 268 individuals. The sequences were used to generate phylogenetic trees to determine clade diversity and also to assess the burden of DRMs. Based on the partial pol sequences, 13 distinct HIV-1 subtypes and recombinant forms were identified. Subtype A1 was the most common clade (40%), followed by CRF02_AG (33.2%). Acquired DRMs were found in 30.6% of the ART-experienced patients, of whom 70.7%, 20.7%, and 8.5% were associated with resistance to NNRTIs, NRTIs, and PIs, respectively. Transmitted DRMs were found in 5.6% of the ART-naïve patients, of whom 93% were associated with resistance against NNRTIs and 7% to PIs. The high prevalence of DRMs in ART-experienced patients poses significant challenges to the long-term benefits and sustainability of the ART program. This study emphasizes the importance of continuous HIV molecular epidemiology and drug resistance surveillance to support evidence-based HIV prevention, precise ART, and targeted AIDS care.

Determining the appropriate computational requirements and software performance is essential for efficient genomic surveillance. The lack of standardized benchmarking complicates software selection, especially with limited resources.

We developed a containerized benchmarking pipeline to evaluate seven long-read assemblers-Canu, GoldRush, MetaFlye, Strainline, HaploDMF, iGDA, and RVHaplo-for viral haplotype reconstruction, using both simulated and experimental Oxford Nanopore sequencing data of HIV-1 and other viruses. Benchmarking was conducted on three computational systems to assess each assembler's performance, utilizing QUAST and BLASTN for quality assessment.

Our findings show that assembler choice significantly impacts assembly time, with CPU and memory usage having minimal effect. Assembler selection also influences the size of the contigs, with a minimum read length of 2,000 nucleotides required for quality assembly. A 4,000-nucleotide read length improves quality further. Canu was efficient among de novo assemblers but not suitable for multi-strain mixtures, while GoldRush produced only consensus assemblies. Strainline and MetaFlye were suitable for metagenomic sequencing data, with Strainline requiring high memory and MetaFlye operable on low-specification machines. Among reference-based assemblers, iGDA had high error rates, RVHaplo showed the best runtime and accuracy but became ineffective with similar sequences, and HaploDMF, utilizing machine learning, had fewer errors with a slightly longer runtime.

The HIV-64148 pipeline, containerized using Docker, facilitates easy deployment and offers flexibility to select from a range of assemblers to match computational systems or study requirements. This tool aids in genome assembly and provides valuable information on HIV-1 sequences, enhancing viral evolution monitoring and understanding.

HIV-1 protease inhibitors are an essential component of antiretroviral therapy. However, drug resistance is a pervasive issue motivating a persistent search for novel therapies. Recent reports found that when protease activates within the host cell's cytosol, it facilitates the pyroptotic killing of infected cells. This has led to speculation that promoting protease activation, rather than inhibiting it, could help to eradicate infected cells and potentially cure HIV-1 infection. Here, we used a nanoscale flow cytometry-based assay to characterize protease resistance mutations and polymorphisms. We quantified protease activity, viral concentration, and premature protease activation and confirmed previous findings that major resistance mutations generally destabilize the protease structure. Intriguingly, we found evidence that common polymorphisms in the hinge domain of protease can influence its susceptibility to premature activation. This suggests that viral heterogeneity could pose a considerable challenge for therapeutic strategies aimed at inducing premature protease activation in the future.

Monitoring the trends of pre-treatment drug resistance (PDR) and resistance-associated mutations (RAMs) among antiretroviral-naïve people with HIV (PWH) is important for the implementation of HIV treatment and control programmes. We analysed the trends of HIV-1 PDR after the introduction of second-generation integrase strand-transfer inhibitors (INSTIs) in 2016 in Taiwan, when single-tablet regimens of non-nucleoside reverse-transcriptase inhibitor (NNRTI-) and INSTI-based antiretroviral therapy became the preferred treatments.

In this multicentre study, we included newly diagnosed, antiretroviral-naïve PWH who underwent tests for RAMs between 2016 and 2022. Pre-treatment genotypic resistance testing was performed, along with HIV-1 subtyping and determinations of plasma HIV RNA load and CD4 lymphocyte counts. RAMs were analysed using the Stanford University HIV Drug Resistance Database and only RAMs conferring at least low-level resistance were included.

From 2016 to 2022, pre-treatment blood samples from 3001 newly diagnosed PWH, which constituted 24.3% of newly diagnosed PWH in Taiwan during the study period, were tested. Of the PWH with analysable gene sequences, the HIV-1 PDR prevalence to NNRTIs, nucleoside reverse-transcriptase inhibitors (NRTIs), first- and second-generation INSTIs and PIs was 10.0%, 2.1%, 2.5%, 0.6% and 0.4%, respectively. While the trends of PDR remained stable for NRTIs, INSTIs and PIs, there was a significantly increasing trend of PDR to NNRTIs from 6.0% in 2016% to 13.1% in 2022 (P = 0.001).

After the introduction of second-generation INSTIs in Taiwan, the trends of HIV-1 PDR to NRTIs and INSTIs remained low. Furthermore, there was no significant decrease of the prevalence of PDR toward NNRTIs between 2016 and 2022.

Treatment options are currently limited for persons with HIV-1 (PWH) who are heavily treatment-experienced and/or have multidrug-resistant HIV-1. Three agents have been approved by the U.S. Food and Drug Administration (FDA) since 2018, representing a significant advancement for this population: ibalizumab, fostemsavir, and lenacapavir. However, there is a paucity of recommendations endorsed by national and international guidelines describing the optimal use (e.g., selection and monitoring after initiation) of these novel antiretrovirals in this population. To address this gap, a modified Delphi technique was used to develop these consensus recommendations that establish a framework for initiating and managing ibalizumab, fostemsavir, or lenacapavir in PWH who are heavily treatment-experienced and/or have multidrug-resistant HIV-1. In addition, future areas of research are also identified and discussed.

Although protein sequences encode the information for folding and function, understanding their link is not an easy task. Unluckily, the prediction of how specific amino acids contribute to these features is still considerably impaired. Here, we developed a simple algorithm that finds positions in a protein sequence with potential to modulate the studied quantitative phenotypes. From a few hundred protein sequences, we perform multiple sequence alignments, obtain the per-position pairwise differences for both the sequence and the observed phenotypes, and calculate the correlation between these last two quantities. We tested our methodology with four cases: archaeal Adenylate Kinases and the organisms optimal growth temperatures, microbial rhodopsins and their maximal absorption wavelengths, mammalian myoglobins and their muscular concentration, and inhibition of HIV protease clinical isolates by two different molecules. We found from 3 to 10 positions tightly associated with those phenotypes, depending on the studied case. We showed that these correlations appear using individual positions but an improvement is achieved when the most correlated positions are jointly analyzed. Noteworthy, we performed phenotype predictions using a simple linear model that links per-position divergences and differences in the observed phenotypes. Predictions are comparable to the state-of-art methodologies which, in most of the cases, are far more complex. All of the calculations are obtained at a very low information cost since the only input needed is a multiple sequence alignment of protein sequences with their associated quantitative phenotypes. The diversity of the explored systems makes our work a valuable tool to find sequence determinants of biological activity modulation and to predict various functional features for uncharacterized members of a protein family.

Drug resistance in HIV type 1 (HIV-1) is a pervasive problem that affects the lives of millions of people worldwide. Although records of drug-resistant mutations (DRMs) have been extensively tabulated within public repositories, our understanding of the evolutionary kinetics of DRMs and how they evolve together remains limited. Epistasis, the interaction between a DRM and other residues in HIV-1 protein sequences, is key to the temporal evolution of drug resistance. We use a Potts sequence-covariation statistical-energy model of HIV-1 protein fitness under drug selection pressure, which captures epistatic interactions between all positions, combined with kinetic Monte-Carlo simulations of sequence evolutionary trajectories, to explore the acquisition of DRMs as they arise in an ensemble of drug-naive patient protein sequences. We follow the time course of 52 DRMs in the enzymes protease, RT, and integrase, the primary targets of antiretroviral therapy. The rates at which DRMs emerge are highly correlated with their observed acquisition rates reported in the literature when drug pressure is applied. This result highlights the central role of epistasis in determining the kinetics governing DRM emergence. Whereas rapidly acquired DRMs begin to accumulate as soon as drug pressure is applied, slowly acquired DRMs are contingent on accessory mutations that appear only after prolonged drug pressure. We provide a foundation for using computational methods to determine the temporal evolution of drug resistance using Potts statistical potentials, which can be used to gain mechanistic insights into drug resistance pathways in HIV-1 and other infectious agents.

People living with human immunodeficiency virus (HIV) receiving integrase strand transfer inhibitors (INSTIs) have been reported to experience virological failure in the absence of resistance mutations in integrase. To elucidate INSTI resistance mechanisms, we propagated HIV-1 in the presence of escalating concentrations of the INSTI dolutegravir. HIV-1 became resistant to dolutegravir by sequentially acquiring mutations in the envelope glycoprotein (Env) and the nucleocapsid protein. The selected Env mutations enhance the ability of the virus to spread via cell-cell transfer, thereby increasing the multiplicity of infection (MOI). While the selected Env mutations confer broad resistance to multiple classes of antiretrovirals, the fold resistance is ~2 logs higher for INSTIs than for other classes of drugs. We demonstrate that INSTIs are more readily overwhelmed by high MOI than other classes of antiretrovirals. Our findings advance the understanding of how HIV-1 can evolve resistance to antiretrovirals, including the potent INSTIs, in the absence of drug-target gene mutations.

Substitution models of evolution are necessary for diverse evolutionary analyses including phylogenetic tree and ancestral sequence reconstructions. At the protein level, empirical substitution models are traditionally used due to their simplicity, but they ignore the variability of substitution patterns among protein sites. Next, in order to improve the realism of the modeling of protein evolution, a series of structurally constrained substitution models were presented, but still they usually ignore constraints on the protein activity. Here, we present a substitution model of protein evolution with selection on both protein structure and enzymatic activity, and that can be applied to phylogenetics. In particular, the model considers the binding affinity of the enzyme-substrate complex as well as structural constraints that include the flexibility of structural flaps, hydrogen bonds, amino acids backbone radius of gyration, and solvent-accessible surface area that are quantified through molecular dynamics simulations. We applied the model to the HIV-1 protease and evaluated it by phylogenetic likelihood in comparison with the best-fitting empirical substitution model and a structurally constrained substitution model that ignores the enzymatic activity. We found that accounting for selection on the protein activity improves the fitting of the modeled functional regions with the real observations, especially in data with high molecular identity, which recommends considering constraints on the protein activity in the development of substitution models of evolution.

Our objective was to characterize longitudinal patterns of viraemia and factors associated with viral suppression in people with HIV and low-level viraemia (LLV) during antiretroviral therapy (ART).

We included people with HIV in the EuResist Integrated Database with LLV following ART initiation after 2005. LLV was defined as two or more consecutive viral load (VL) measurements of 51-199 copies/mL 30-365 days apart after >12 months of ART. Viraemia patterns were analyzed over 24 months. Factors associated with viral suppression at 12 months after LLV episodes were identified using univariable and multivariable logistic regression.

Of 25 113 people with HIV, 2474 (9.9%) had LLV. Among 1387 participants with 24 months of follow-up after LLV, 406 (29%) had persistent suppression, 669 (48%) had transient viraemic episodes, 29 (2%) had persistent LLV, and 283 (20%) had virological failure. Following LLV episodes, the proportion with detectable viraemia declined (p for trend <0.001 and 0.034, in the first and second year, respectively). At 12 months, 68% had undetectable VL, which was associated with suppression before LLV (adjusted odds ratio [aOR] 1.7; 95% confidence interval [CI] 1.2-2.4) and ART modification after LLV (aOR 1.6; 95% CI 1.0-2.4). The following factors were negatively associated with undetectable VL at 12 months: higher VL during LLV (aOR 0.57 per log10 copies/mL; 95% CI 0.37-0.89), injecting drug use (aOR 0.67; 95% CI 0.47-0.96), and regimens with protease inhibitors (aOR 0.65; 95% CI 0.49-0.87) or combined anchor drugs (aOR 0.52; 95% CI 0.32-0.85).

Most people with LLV did not experience sustained viral suppression during 24-month follow-up, supporting the association between LLV and inferior treatment outcome.

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic posed an unpreceded threat to the management of other pandemics such as human immunodeficiency virus-1 (HIV-1) in the United States. The full impact of the SARS-CoV-2 pandemic on the HIV-1 pandemic needs to be evaluated.

All individuals with newly reported HIV-1 diagnoses from NC State Laboratory of Public Health were enrolled in this prospective observational study, 2018-2021. We used a sequencing-based recency assay to identify recent HIV-1 infections and to determine the days postinfection (DPI) for each person at the time of diagnosis.

Sequencing used diagnostic serum samples from 814 individuals with new HIV-1 diagnoses spanning this 4-year period. Characteristics of individuals diagnosed in 2020 differed from those in other years. People of color diagnosed in 2021 were on average 6 months delayed in their diagnosis compared to those diagnosed in 2020. There was a trend that genetic networks were more known for individuals diagnosed in 2021. We observed no major integrase resistance mutations over the course of the study.

SARS-CoV-2 pandemic may contribute to the spread of HIV-1. Public health resources need to focus on restoring HIV-1 testing and interrupting active, ongoing, transmission.

After a decade of dolutegravir (DTG) use in various antiretroviral therapy combinations and in diverse populations globally, it is critical to identify HIV strains with reduced drug susceptibility and monitor emergent resistance in people living with HIV who experience virologic failure while on DTG-based regimens. We searched the PubMed, Embase, and Cochrane databases to identify studies that reported DTG resistance-associated mutations (RAMs) emerging under selection pressure. Our review showed that RAMs conferring resistance to DTG were rare in 2-drug and 3-drug regimens used in real-world cohorts, corroborating data from clinical trials. The potency of DTG in maintaining virologic suppression was demonstrated, even in cases of pre-existing resistance to companion drugs in the regimen. Estimates of DTG RAMs depended on the population and certain risk factors, including monotherapy, baseline resistance or lack of genotypic testing, treatment history and prior virologic failure, and suboptimal treatment adherence. The RAMs detected after virologic failure, often in heavily treatment-experienced individuals with prior exposure to integrase strand transfer inhibitors, were G118R, E138K, G140A/C/R/S, Q148H/K/R, N155H, and R263K. Overall, these data highlight the durable effectiveness and high barrier to resistance of DTG as part of combination antiretroviral therapy in a wide variety of settings.