Impact of pretreatment low-abundance HIV-1 drug resistance on virological failure after 1 year of antiretroviral therapy in China.

OBJECTIVES: To assess the impact of pretreatment low-abundance HIV drug-resistant variants (LA-DRVs) on virological outcomes among ART-naive HIV-1-infected Chinese people who initiated ART. METHODS: A nested case-control study was conducted among HIV-1-infected individuals who had pretreatment drug resistance (PDR) genotypic results. Cases were defined as individuals with virological failure (HIV-1 RNA viral load ≥1000 copies/mL) after 1 year of ART, and controls were individuals from the same cohort whose viral load was less than 1000 copies/mL. Next-generation sequencing was used to identify low-abundance PDR mutations at detection thresholds of 10%, 2% and 1%. The mutant load was calculated by multiplying the abundance of HIV-1 drug-resistant variants by the pretreatment viral load. The impact of pretreatment low-abundance mutations on virological failure was estimated in logistic regression models. RESULTS: Participants (43 cases and 100 controls) were included in this study for the analysis. The proportion of participants with PDR was higher in cases than in controls at different detection thresholds (44.2% versus 22.0%, P = 0.007 at 10% threshold; 58.1% versus 31.0%, P = 0.002 at 2% threshold; 90.7% versus 69.0%, P = 0.006 at 1% threshold). Compared with participants without PDR, participants with ≥10% detectable PDR mutations were associated with an increased risk of virological failure (adjusted OR 8.0, 95% CI 2.4-26.3, P = 0.001). Besides this, individuals with pretreatment LA-DRVs (2%-9% abundance range) had 5-fold higher odds of virological failure (adjusted OR 5.0, 95% CI 1.3-19.6, P = 0.021). Furthermore, LA-DRVs at 2%-9% abundance resistant to NRTIs and mutants with abundance of ≥10% resistant to NNRTIs had a 4-fold and 8-fold risk of experiencing virological failure, respectively. It was also found that a mutant load of more than 1000 copies/mL was predictive of virological failure (adjusted OR 7.2, 95% CI 2.5-21.1, P = 0.0003). CONCLUSIONS: Low-abundance PDR mutations ranging from 2% to 9% of abundance can increase the risk of virological failure. Further studies are warranted to define a clinically relevant threshold of LA-DRVs and the role of NRTI LA-DRVs.

Modelling the impact of treatment adherence on the transmission of HIV drug resistance.

INTRODUCTION: A lower adherence rate (percentage of individuals taking drugs as prescribed) to ART may increase the risk of emergence and transmission of HIV drug resistance, decrease treatment efficacy, and increase mortality rate. Exploring the impact of ART adherence on the transmission of drug resistance could provide insights in controlling the HIV epidemic. METHODS: We proposed a dynamic transmission model incorporating the CD4 cell count-dependent rates of diagnosis, treatment and adherence with transmitted drug resistance (TDR) and acquired drug resistance. This model was calibrated and validated by 2008-2018 HIV/AIDS surveillance data and prevalence of TDR among newly diagnosed treatment-naive individuals from Guangxi, China, respectively. We aimed to identify the impact of adherence on drug resistance and deaths during expanding ART. RESULTS: In the base case (ART at 90% adherence and 79% coverage), we projected the cumulative total new infections, new drug-resistant infections, and HIV-related deaths between 2022 and 2050 would be 420 539, 34 751 and 321 671. Increasing coverage to 95% would reduce the above total new infections (deaths) by 18.85% (15.75%). Reducing adherence to below 57.08% (40.84%) would offset these benefits of increasing coverage to 95% in reducing infections (deaths). Every 10% decrease in adherence would need 5.07% (3.62%) increase in coverage to avoid an increase in infections (deaths). Increasing coverage to 95% with 90% (80%) adherence would increase the above drug-resistant infections by 11.66% (32.98%). CONCLUSIONS: A decrease in adherence might offset the benefits of ART expansion and exacerbate the transmission of drug resistance. Ensuring treated patients' adherence might be as important as expanding ART to untreated individuals.

HIV transmission and associated factors under the scale-up of HIV antiretroviral therapy: a population-based longitudinal molecular network study.

OBJECTIVES: To evaluate the prevention efficacy of scaling up HIV/AIDS antiretroviral therapy (ART) on HIV transmission at the population level and determine associated factors of HIV secondary transmission. METHODS: We used HIV longitudinal molecular networks to assess the genetic linkage between baseline and newly diagnosed cases. A generalized estimating equation was applied to determine the associations between demographic, clinical characteristics and HIV transmission. RESULTS: Patients on ART had a 32% lower risk of HIV transmission than those not on ART. A 36% reduction in risk was also seen if ART-patients maintained their HIV viral load lower than 50 copies/mL. A 71% lower risk occurred when patients sustained ART for at least 3 years and kept HIV viral load less than 50 copies/mL. Patients who discontinued ART had a similar HIV transmission risk as those not on ART. Patients who were older, male, non-Han, not single, retired, infected via a heterosexual route of transmission and those who possessed higher CD4 counts had a higher risk of HIV transmission. HIV-1 subtype of CRF01_AE was less transmissible than other subtypes. CONCLUSIONS: The efficacy of ART in a real-world setting was supported by this longitudinal molecular network study. Promoting adherence to ART is crucial to reduce HIV transmission.

Impact of low-level viremia with drug resistance on CD4 cell counts among people living with HIV on antiretroviral treatment in China.

BACKGROUND: Maintaining plasma HIV RNA suppression below the limit of quantification is the goal of antiretroviral therapy (ART). When viral loads (VL) remain in low-level viremia (LLV), or between 201 and 999 copies/mL, the clinical consequences are still not clear. We investigated the occurrence of LLV with drug resistance and its effect on CD4 cell counts in a large Chinese cohort. METHODS: We analysed data of 6,530 ART-experienced patients (42.1 ± 10.9 years; 37.3% female) from the China's national HIV drug resistance (HIVDR) surveillance database. Participants were followed up for 32.9 (IQR 16.7-50.5) months. LLV was defined as the occurrence of at least one viral load (VL) measurement of 50-200 copies/mL during ART. Outcomes were drug resistance associated mutations (DRAM) and CD4 cell counts levels. RESULTS: Among 6530 patients, 58.0% patients achieved VL less than 50 copies/mL, 27.8% with VL between 50 and 999 copies/mL (8.6% experienced LLV), and 14.2% had a VL ≥ 1000 copies/mL. Of 1818 patients with VL 50-999 copies/mL, 182 (10.0%) experienced HIVDR, the most common DRAM were M184I/V 28.6%, K103N 19.2%, and V181C/I/V 10.4% (multidrug resistance: 27.5%), and patients with HIVDR had a higher risk of CD4 cell counts < 200 cells/µL (AOR 3.8, 95% CI 2.6-5.5, p < 0.01) comparing with those without HIVDR. Of 925 patients with VL ≥ 1000 copies/mL, 495 (53.5%) acquired HIVDR, the most common DRAM were K103N 43.8%, M184I/V 43.2%, M41L 19.0%, D67N/G 16.4%, V181C/I/V 14.5%, G190A/S 13.9% and K101E 13.7% (multidrug resistance: 75.8%), and patients with HIVDR had a higher risk of CD4 cell counts < 200 cells/µL (AOR 5.8, 95% CI 4.6-7.4, p < 0.01) comparing with those without HIVDR. CONCLUSION: Persistent with VL 50-999 copies/mL on ART is associated with emerging DRAM for all drug classes, and patients in this setting were at increased risk of CD4 cell counts < 200 cells/µL, which suggest resistance monitoring and ART optimization be earlier considered.

Survey of pretreatment HIV drug resistance and the genetic transmission networks among HIV-positive individuals in southwestern China, 2014-2020.

BACKGROUND: Pretreatment drug resistance (PDR) can limit the effectiveness of HIV antiretroviral therapy (ART). The aim of this study was to assess the prevalence of PDR among HIV-positive individuals that initiated antiretroviral therapy in 2014-2020 in southwestern China. METHODS: Consecutive cross-sectional surveys were conducted in Qinzhou, Guangxi. We obtained blood samples from individuals who were newly diagnosed with HIV in 2014-2020. PDR and genetic networks analyses were performed by HIV-1 pol sequences using the Stanford HIV-database algorithm and HIV-TRACE, respectively. Univariate and multivariate logistic regression models were used to explore the potential factors associated with PDR. RESULTS: In total, 3236 eligible HIV-positive individuals were included. The overall prevalence of PDR was 6.0% (194/3236). The PDR frequency to NNRTI (3.3%) was much higher than that of NRTI (1.7%, p < 0.001) and PI (1.2%, p < 0.001). A multivariate logistic regression analysis revealed that PDR was significantly higher among individuals aged 18-29 (adjusted odds ratio (aOR): 1.79, 95% CI 1.28-2.50) or 30-49 (aOR: 2.82, 95% CI 1.73-4.82), and harboring CRF08_BC (aOR: 3.23, 95% CI 1.58-6.59). A total of 1429 (43.8%) sequences were linked forming transmission clusters ranging in size from 2 to 119 individuals. Twenty-two individuals in 10 clusters had the same drug resistant mutations (DRMs), mostly to NNRTIs (50%, 5/10). CONCLUSIONS: The overall prevalence of PDR was medium, numerous cases of the same DRMs among genetically linked individuals in networks further illustrated the importance of surveillance studies for mitigating PDR.

HIV drug resistance in patients in China's national HIV treatment programme who have been on first-line ART for at least 9 months.

BACKGROUND: The aim of this study was to assess trends in drug resistance and associated clinical and programmatic factors at a national level during the rapid scale up of ART. METHODS: Logistic regression was used to identify the factors associated with HIVDR. Variables associated with drug resistance in multivariable logistic regression were included in the Cochran-Armitage test for trend. RESULTS: A total of 11,976 patients were enrolled in the study. The prevalence of HIVDR among patients who received ART for 9-24 months during 2003-2008, 2009-2012, and 2013-2015 significantly decreased (15.5%, 6.3%, and 2.3%, respectively, P < 0.01). With respect to the class of antiretroviral, there were substantial increases in resistance to both non-nucleoside reverse transcriptase inhibitors (NNRTIs) and nucleoside reverse transcriptase inhibitors (NRTIs) (2003-2008, 2009-2012, and 2013-2015: 49.7%, 58.9%, and 73.0%, respectively, P < 0.01). The prevalence of DR to protease inhibitors (PIs) was low, which supported their continued use as second-line therapy in China. CONCLUSIONS: Our results provide evidence for the effectiveness of China's "Treat All" approach to guide policy makers to improve training for healthcare providers and education on ART adherence among patients.

Effects of CD4 Cell Counts and Viral Load Testing on Mortality Rates in Patients With HIV Infection Receiving Antiretroviral Treatment: An Observational Cohort Study in Rural Southwest China.

BACKGROUND: Recent studies have suggested that CD4 cell count monitoring has little added value in patients who are virologically suppressed and immunologically stable if viral load (VL) testing is routinely available. These conclusions have not been directly assessed using mortality rate as a study end point in a real-world setting. METHODS: This human immunodeficiency virus (HIV) treatment cohort study from 2008 to 2014 was conducted in Guangxi, China. We used a Cox regression model to analyze associations between the frequency of CD4 cell counts and VL testing and death. RESULTS: Compared with monitoring CD4 cell counts ≥3 times during the first year of antiretroviral therapy (ART) initiation, as currently suggested by the Chinese National Free Antiretroviral Treatment Program, monitoring them less than twice during the first year of ART was significantly associated with death; however, monitoring them twice in that year did not significantly increase mortality rates. Compared with testing VL at least once during the first year of ART, as currently suggested by the National Free Antiretroviral Treatment Program, performing no VL tests in the first year after ART initiation was significantly associated with higher mortality rates. Routine CD4 cell count monitoring did not have an impact on mortality rates among HIV-infected patients with VLs <1000 copies/mL or CD4 cell counts ≥350/µL beyond 12 months after ART initiation. CONCLUSIONS: Our study suggests that CD4 cell counts can be reduced to twice during the first year of ART and be reduced or stopped for patients who have achieved virologic suppression or immunologic stability after 12 months of treatment.

Reductions in virological failure and drug resistance in Chinese antiretroviral-treated patients due to lamivudine-based regimens, 2003-12.

BACKGROUND: China's National Free Antiretroviral Treatment Program (NFATP) has significantly scaled up and standardized treatment since 2008. Meanwhile, no study worldwide has examined on a large scale the effects of rapid ART programme scale-up on treatment outcomes in resource-limited settings. METHODS: We used China's national HIV drug resistance (HIVDR) surveillance database to determine virological failure, acquired drug resistance and poor adherence rates after 12-15 months of first-line ART. A total of 2252 patients were examined, with 1431 patients having initiated ART before 2008 and 821 since 2008. FINDINGS: Since 2008, virological failure at 12-15 months of treatment improved from 26.6% to 12.1%, and HIVDR rates also significantly decreased from 15.4% to 5.4%. However, these successes are strongly associated with the standardized use of lamivudine-based regimens in place of didanosine-based regimens. Patients who initiated lamivudine-based regimens before 2008 showed significant improvement in adherence [missed doses adjusted OR (AOR), 0.65; 95% CI, 0.45-0.96], virological failure (AOR, 0.29; 95% CI, 0.22-0.39) and HIVDR outcomes (AOR, 0.29; 95% CI, 0.20-0.42) compared with those who initiated didanosine-based regimens. Meanwhile, among only patients on lamivudine-based regimens, no significant changes were observed between those who initiated before 2008 and those who initiated since 2008. CONCLUSIONS: China's NFATP has been largely successful throughout the scale-up, with an overall reduction in virological failure and HIVDR. However, excluding the effect of lamivudine-based regimens, it remains crucial for the programme to improve patient adherence and quality of care, particularly in key vulnerable populations such as those infected through injecting drug or blood routes.

CorMut: an R/Bioconductor package for computing correlated mutations based on selection pressure.

UNLABELLED: Correlated mutations constitute a fundamental idea in evolutionary biology, and understanding correlated mutations will, in turn, facilitate an understanding of the genetic mechanisms governing evolution. CorMut is an R package designed to compute correlated mutations in the unit of codon or amino acid mutation. Three classical methods were incorporated, and the computation results can be represented as correlation mutation networks. CorMut also enables the comparison of correlated mutations between two different evolutionary conditions. AVAILABILITY AND IMPLEMENTATION: CorMut is released under the GNU General Public License within bioconductor project, and freely available at http://bioconductor.org/packages/release/bioc/html/CorMut.html.

The development of drug resistance mutations K103N Y181C and G190A in long term Nevirapine-containing antiviral therapy.

OBJECTIVE: We built a cohort study of HIV patients taking long-term first-line Antiretroviral Therapy in 2003. In this assay, we focused on the development of primary drug resistance mutations against Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI), K103N, Y181C and G190A. METHOD: The cohort study was built in Henan province, China. We used Single Genome Amplification (SGA) to analyze the frequency of K103N, Y181C and G190A in serial plasma samples of three individual patients. We also performed standard genotype HIV drug resistance assay in 204 patients of this cohort study to analyze the frequency of these mutations. RESULT: In the SGA sequences, the K103N decreased and vanished, while the frequency of Y181C and G190A increased in individual patient receiving long-term Antiretroviral Therapy (ART). In the sequences of standard genotype HIV drug resistance assay, the frequency of K103N, Y181C and G190A had the similar pattern with that in SGA sequences. Among these patients, the viral suppression were still sufficient after receiving ART for 72 months, and 78.6% (160/204) patients could have their CD4 count over than 200cells/ul. CONCLUSION: In some patients, first-line ART had the possibility to provide sufficient treatment effect for over than 72 months, but in long-term treatment, the dominant NNRTI drug resistance mutation K103N could reduced, while the proportion of variants with mutation Y181C or G190A may increased. This result was not similar with that in vitro study, which state that variant with K103N or Y181C had an equal viral fitness with wild type.

[Resistance evolutionary pathway analysis of HIV-1 CRF_07BC reverse transcriptase].

OBJECTIVE: To study resistance evolution pathway of HIV-1 CRF_BC under drug selection pressure, and compare with B subtype. METHODS: Based on the reverse transcriptase region of CRF_ 97BC HIV-1 from 588 treatment-naive and 274 treatment patients, selection pressure based method was used to select resistance-associated mutations, and Bayesian network was used to construct the resistance evolutionary pathway under antiretroviral therapy. Meanwhile, it was constructed that the resistance evolutionary pathway for B subtype with the same regimens using the data from HIV resistance database, and made a comparison with CRF_07BC. RESULTS: The major resistance mutations for CRF_07BC were identified including K103N, Q197K, V179D and Y188L. While for B subtype, the major resistance mutations include M184V, K103N,Y181C, T69N,G190A, K238T,Y188H and P225H. Much difference was observed between these two classes. However, the classical TMA1 (41L, 210W and 215Y) and TMA2 (67N, 70R and 219E/Q) pathways exist in both pathways. As different from B subtype, the predicted major drug resistance mutations for CRF_07BC did not contain TAM-related mutations, and nucleoside reverse transcriptase inhibitor-related mutations and non-nucleoside reverse transcriptase inhibitor-related mutations were mutually depending on each other. CONCLUSION: HIV-1 CRF_07BC showed distinctive resistance evolutionary pathway, the mutations K103N,Q197K,V179D and Y188L were the major resistance mutations, and different resistance evolutionary pathways were observed between HIV-1 CRF_07BC and B subtype.

Criteria for classification, nomenclature, and reference sequence selection for HIV sub-subtypes of CRF01_AE and CRF07_BC strains in China.

The available knowledge regarding classification, nomenclature, and reference sequence selection for the various sub-subtypes of circulating recombinant forms (CRFs) is inadequate to fulfill the growing demands of research focused on HIV prevention. We analyzed the spread of CRF01_AE and CRF07_BC strains, mainly in China, to complement and update the existing nomenclature and to propose a reference sequence selection criteria for sub-subtypes of CRFs.

Plasma proteomics analysis of Chinese HIV-1 infected individuals focusing on the immune and inflammatory factors afford insight into the viral control mechanism.

Background: Long-term non-progressors (LTNPs) with HIV infection can naturally control viral replication for up to a decade without antiretroviral therapy (ART), but the underlying mechanisms of this phenomenon remain elusive. Methods: To investigate the relevant immune and inflammatory factors associated with this natural control mechanism, we collected plasma samples from 16 LTNPs, 14 untreated viral progressors (VPs), 17 successfully ART-treated patients (TPs), and 16 healthy controls (HCs). The OLINK immune response panel and inflammation panel were employed to detect critical proteins, and the plasma neutralizing activity against a global panel of pseudoviruses was assessed using TZM-bl cells. Results: The combination of IL17C, IL18, DDX58, and NF2 contributed to discriminating LTNPs and VPs. IL18 and CCL25 were positively associated with CD4+ T cell counts but negatively correlated with viral load. Furthermore, CXCL9 and CXCL10 emerged as potential supplementary diagnostic markers for assessing the efficacy of antiretroviral therapy (ART). Finally, TNFRSF9 displayed positive correlations with neutralization breadth and Geometry Median Titer (GMT) despite the lack of significant differences between LTNPs and VPs. Conclusion: In summary, this study identified a set of biomarkers in HIV-infected individuals at different disease stages. These markers constitute a potential network for immune balance regulation in HIV infection, which is related to the long-term control of HIV by LTNPs. It provides important clues for further exploring the immune regulatory mechanism of HIV.

Full-Spectrum Surveillance of Pre-Treatment HIV Drug Resistance in Southeastern China.

HIV drug resistance compromises the ability of anti-retroviral therapy (ART) to suppress viral replication, resulting in treatment failure. This study investigates the prevalence of pre-treatment drug resistance (PDR) in newly diagnosed individuals in a prosperous city (Wenzhou) in Southeastern China. A cross-sectional investigation was carried out among 473 newly diagnosed ART-naive HIV-1-infected individuals between January and December 2022. The protease-reverse transcriptase (PR-RT) region and integrase (IN) region of HIV-1 were amplified by two separately nested PCRs, followed by sequencing. Drug resistance mutations (DRMs) and drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs) and integrase strand transfer inhibitors (INSTIs) were analyzed. The PDR prevalence was 6.5% [95% CI: 4.4-9.1] for any anti-retroviral drug, 0.9% [95% CI: 0.3-2.3] for NRTIs, 4.1% [95% CI: 2.5-6.5] for NNRTIs, 1.8% [95% CI: 0.8-3.6] for PIs and 0.5% [95% CI: 0.1-1.8] for INSTIs. According to the subtyping results of the PR-RT region, 11 different subtypes and 31 unique recombinant forms (URFs) were found. CRF07_BC was the dominant subtype (53.7%, 233/434), followed by CRF01_AE (25.3%, 110/434). V179D (1.6%) and K103N (1.4%) were the most predominant types of NNRTI DRMs. Q58E (1.2%) and M184V (0.7%) were the most frequent PI DRMs and NRTI DRMs, respectively. The INSTI-related DRMs Y143S (causes high-level resistance to RAL) and G163K (causes low-level resistance to EVG and RAL) were found in one patient each. Given the relatively high PDR prevalence of NNRTI (4.1%), non-NNRTI-based ART may be preferred in the future. It is recommended to include genotypic resistance testing before starting ART in regions where feasible.

HBV and HCV Co-Infection in Chinese Newly Diagnosed HIV+ Subjects in 2015 and 2023: A Cross-Sectional Study.

With shared routes of transmission, HBV and HCV co-infection are estimated to occur more in subjects with HIV. This study aimed to characterize and describe the prevalence of HBV and HCV co-infections in a cohort of newly diagnosed HIV+ subjects living in China. We conducted a cross-sectional study among newly diagnosed HIV+ subjects aged 18-100 who participated in surveys on the national HIV molecular epidemiology in 2015 and 2023. (The epidemiological table survey is located in the national database alongside serologic testing). The chi-square test was used to identify changes in infections between the studying populations in 2015 and 2023, and conditional logistic regression models were fit to identify risk factors for each co-infection. Among the 11,024 newly diagnosed HIV+ subjects who were surveyed (n = 4501 in 2015; n = 6523 in 2023), the prevalence of HBV, HCV, and HBV/HCV in 2023 was lower than that in 2015, respectively. No decrease was observed in HCV co-infection in men who had sex with men (MSM) in North China, Northeast China, and East China. Increasing recognition among those at high risk of heterosexual transmission and those with low educational backgrounds is paramount to the prevention and control of HIV/HBV/HCV infections.

Mutation covariation of HIV-1 CRF07_BC reverse transcriptase during antiretroviral therapy.

OBJECTIVES: To understand the effect of HIV-1 drug resistance mutations in the context of antiretroviral therapy (ART), we compared the prevalence of protease (PR) and reverse transcriptase (RT) mutations in HIV-1 CRF07_BC sequences from blood samples of treatment-naive and ART-treated patients. METHODS: Mutation covariation in the RT and PR of HIV-1 CRF07_BC viruses from 542 treatment-naive patients and 261 patients treated with lamivudine/zidovudine/nevirapine or lamivudine/zidovudine/efavirenz was analysed. Stratified networks were used to display the mutation covariation. RESULTS: Based on the comparison between treatment-naive and ART-treated patients, three types of featured mutations for RT and PR were initially identified: treatment-associated mutations, treatment-agonistic mutations and overlapping polymorphisms. Twelve significant covariation pairs were found between five treatment-associated mutations (K103N, M184V, Q197K, G190A and Y181C) and nine overlapping polymorphisms (A36E, D39N, Y121H, D123E, R135I, T200A, R277K, L283I and D291E). Meanwhile, three covariation pairs between three treatment-associated mutations (I132L and M184V for RT and I15V for PR) and three overlapping polymorphisms (L10I, L36M and A71V) for PR were also detected. Finally, the overlapping polymorphisms for RT and PR were both found to have significant correlations with treatment-associated mutations, indicating a possible association between polymorphisms and drug resistance. When compared with HIV-1 subtype B under the same regimens as CRF07_BC, the mutation covariations of CRF07_BC showed a distinct pattern of RT and PR mutation covariation. CONCLUSIONS: The role of polymorphisms in the development of drug resistance has been widely reported. Here, we found a significant correlation between overlapping polymorphisms for RT and PR and treatment-associated mutations, indicating that polymorphisms exert a global influence on treatment-associated mutations. Polymorphism mutations might therefore be considered before initiating ART to improve the efficacy of drug combinations.

The emergence of HIV-1 primary drug resistance genotypes among treatment-naïve men who have sex with men in high-prevalence areas in China.

The prevalence of HIV-1 infection in men who have sex with men (MSM) in China has drastically increased, and circulating strains may have acquired transmitted drug resistance (TDR). We determined TDR genotypes among antiretroviral therapy (ART)-naïve MSM in 19 provinces/cities where HIV-1 prevalence among MSM is high, and found an overall 4.9 % TDR rate. Although protease inhibitors (PI) were not in the first-line antiretroviral drug list provided through the National ART Program, 70.4 % of the detected TDR belongs to this category. Our findings confirm the urgent need for TDR surveillance in order to optimize treatment effects of the National ART Program.

HIV-1 Disease Progression and Drug Resistance Mutations among Children on First-Line Antiretroviral Therapy in Ethiopia.

Background: High rates of disease progression and HIV drug resistance (HIVDR) among adults taking highly active antiretroviral treatment (HAART) in Sub-Saharan Africa were previously documented. However, children were generally not considered despite their greater risk. Hence, this study was aimed to evaluate HIV-1 disease progression and drug resistance mutation among children on first-line antiretroviral therapy in Ethiopia. Method: A longitudinal study was conducted among 551 HIV-positive children (<15 years old) recruited between 2017 and 2019 at 40 antiretroviral treatment delivery sites in Ethiopia. Disease progression was retrospectively measured over a 12-year (2007-2019) follow-up as the progress towards immunosuppression. Two consecutive viral load (VL) tests were conducted in 6-month intervals to assess virologic failure (VF). For children with VF, HIV-1 genotyping and sequencing was performed for the pol gene region using in-house assay validated at the Chinese Center for Disease Control and Prevention, and the Stanford HIVDB v9.0 algorithm was used for identification of drug resistance mutations. The Kaplan-Meier analysis and Cox proportional hazards regression model were used to estimate the rate and predictors of disease progression, respectively. Results: The disease progression rate was 6.3 per 100 person-years-observation (95% CI = 4.21-8.53). Overall immunosuppression (CD4 count < 200 cells/mm3) during the 12-year follow-up was 11.3% (95% CI = 7.5-15.1). Immunosuppression was significantly increased as of the mean duration of 10.5 (95% CI = 10.1-10.8) years (38.2%) to 67.8% at 12 years (p < 0.001). Overall, 14.5% had resistance to at least one drug, and 6.2% had multi-drug resistance. A resistance of 67.8% was observed among children with VF. Resistance to non-nucleotide reverse transcriptase inhibitors (NNRTI) and nucleotide reverse transcriptase inhibitors (NRTI) drugs were 11.4% and 10.1%, respectively. Mutations responsible for NRTI resistance were M184V (30.1%), K65R (12.1%), and D67N (5.6%). Moreover, NNRTI-associated mutations were K103N (14.8%), Y181C (11.8%), and G190A (7.7%). Children who had a history of opportunistic infection [AHR (95% CI) = 3.4 (1.8-6.2)], vitamin D < 20 ng/mL [AHR (95% CI) = 4.5 (2.1-9.9)], drug resistance [AHR (95% CI) = 2.2 (1.4-3.6)], and VF [AHR (95% CI) = 2.82 (1.21, 3.53)] had a higher hazard of disease progression; whereas, being orphan [AOR (95% CI) = 1.8 (1.2-3.1)], history of drug substitution [(AOR (95% CI) = 4.8 (2.1-6.5), hemoglobin < 12 mg/dL [AOR (95% CI) = 1.2 (1.1-2.1)] had higher odds of developing drug resistance. Conclusions: Immunosuppression was increasing over time and drug resistance was also substantially high. Enhancing routine monitoring of viral load and HIVDR and providing a vitamin-D supplement during clinical management could help improve the immunologic outcome. Limiting HAART substitution is also crucial for children taking HAART in Ethiopia.

Substitution of gp120 C4 region compensates for V3 loss-of-fitness mutations in HIV-1 CRF01_AE co-receptor switching.

HIV-1 infection is mediated by a viral envelope subsequently binding to CD4 receptor and two main coreceptors, CCR5 (R5) for primary infection and CXCR4 (X4) in chronic infection. Switching from R5 to X4 tropism in HIV-1 infection is associated with increased viral pathogenesis and disease progression. The coreceptor switching is mainly due to variations in the V3 loop, while the mechanism needs to be further elucidated. We systematically studied the determinant for HIV-1 coreceptor switching by substitution of the genes from one R5 and one X4 pseudoviruses. The study results in successfully constructing two panels of chimeric viruses of R5 to X4 forward and X4 to R5 reverse switching. The determinants for tropism switching are the combined substitution of the V3 loop and C4 region of the HIV-1 envelope. The possible mechanism of the tropism switching includes two components, the V3 loop to enable the viral envelope binding to the newly switched coreceptor and the C4 region, to compensate for the loss of fitness caused by deleterious V3 loop mutations to maintain the overall viral viability. The combined C4 and V3 substitution showed at least an eightfold increase in replication activity compared with the pseudovirus with only V3 loop substitution. The site-directed mutations of N425R and S440-I442 with charged amino acids could especially increase viral activity. This study could facilitate HIV-1 phenotype surveillance and select right entry inhibitor, CCR5 or CXCR4 antagonists, for antiviral therapy.

Burden of hepatitis B virus and syphilis co-infections and its impact on HIV treatment outcome in Ethiopia: nationwide community-based study.

BACKGROUND: Hepatitis B virus (HBV) and syphilis have been the most common co-infections that hinder treatment outcomes and increase early mortality among people living with human immunodeficiency virus (PLHIV). In this study, we aimed to determine the burden of HBV and syphilis co-infections and its impact on treatment outcomes among PLHIV in Ethiopia. METHODS: We used data from the Ethiopian Population-based HIV Impact Assessment (EPHIA), which was a household-based national survey in 2017/2018. Human immunodeficiency virus (HIV) testing was done among 19,136 participants using the national testing algorithm and 662 participants (3.50%) were HIV positives who were further tested for viral hepatitis and syphilis co-infections using HBV surface antigen and Chembio DPP syphilis assay, respectively. Viral load, CD4 count and high-sensitivity C-reactive protein (hsCRP) were done to measure HIV treatment outcomes. Descriptive statistics were used to determine the burden of co-infections and a logistic regression model to evaluate the determinants of co-infections using STATA V17.0. RESULTS: Overall prevalence of HBV and syphilis co-infection was 5.5% and 2.2%, respectively. HBV and syphilis (double co-infection) was 5.9%. The highest prevalence of HBV co-infection was observed among 10-19 years age group (12.9%) and male participants (7.44%) while the highest syphilis co-infection was among people aged ≥50 years (3.5%) followed by age groups 40-49 (3.3%) and 10-19 years (3.2%). Syphilis co-infection was higher among males (5.2%) compared to females (1.1%). After adjusted regression analysis, HBV co-infected PLHIV had higher odds of virologic failure (AOR (95% confidence interval (CI)) = 6.3 (4.2-14.3)), immunosuppression (CD4 count < 500 cells/mm3) (AOR (95%CI) = 2.1(1.3-4.9)) and inflammation (hsCRP >10 mg/dL) (AOR (95%CI) = 9.2(4.3-14.6)). Immunosuppression was also significantly higher among syphilis co-infected PLHIV (AOR (95%CI) = 3.4 (1.3-5.2)). CONCLUSIONS: Burden of HBV and syphilis co-infections is high particularly among male and adolescent PLHIV and these co-infections hinder virologic and immunologic outcome in Ethiopia. Hence, the program shall enhance HBV and syphilis testing and treatment.