High HIV-1 Diversity and Prevalence of Transmitted Drug Resistance Among Antiretroviral-Naive HIV-Infected Pregnant Women from Rio de Janeiro, Brazil

Treatment Management Challenges in Naïve and Experienced HIV-1-Infected Individuals Carrying the M184V Mutation

M184V is a single-base mutation in the YMDD domain of reverse transcriptase (RT). The M184V resistance-associated mutation (RAM) is related to virological unresponsiveness to lamivudine (3TC) and emtricitabine (FTC) and induces high-level resistance to these two antiretroviral agents. M184V is rapidly selected in the setting of non-suppressive antiretroviral therapy (ART) and accumulates in the HIV reservoir. There were continuous efforts to evaluate the impact of the M184V mutation on the treatment outcomes in people living with HIV (PLWH). Since 3TC remains an extensively used part of recommended antiretroviral combinations, M184V is commonly detected in patients with virological failure (VF). ART guidelines do not recommend the use of drugs impacted by RAMs as they have been confirmed to comprise a risk factor for VF. However, there is evidence that 3TC/FTC can remain active even in the presence of M184V. Given the potential benefits of 3TC in ART combinations, the investigation of M184V remains of high interest to clinicians and researchers, especially in certain regions with limited resources, and especially for its unusual effects. This is a review of the literature on the challenges in treating both naïve and experienced individuals carrying the M184V mutation, including virological failure, virological suppression, and resistance to ART.

Prevalence of HIV-1 infection and associated characteristics in a Brazilian indigenous population: a cross-sectional study

BACKGROUND

Despite significant progress in the areas of prevention, diagnosis, and treatment, HIV continues to result in a substantial number of fatalities on a global scale each year. Gaining insights from epidemiological data can prove instrumental in the development of health promotion strategies, particularly within vulnerable populations, such as indigenous groups. Consequently, our study aimed to investigate the prevalence of HIV infection within the indigenous population residing in the second-largest region of Brazil. Additionally, we sought to explore the subtypes of HIV-1 and detect any drug-resistance mutations present within this population.

METHODS

In this cross-sectional study, we aimed to evaluate the prevalence of HIV-1 infection and explore its associated characteristics within the indigenous population residing in the villages of Jaguapiru and Bororó, located in the Dourados area of Mato Grosso do Sul (MS), Brazil. Blood samples were collected for rapid HIV screening, serological tests, nucleic acid amplification, and HIV subtyping. Additionally, the HIV-1 viral load and CD4+ T lymphocyte count of the people living with HIV (PLHIV) were assessed at the time of recruitment and 24 weeks later.

FINDINGS

Out of the 2190 invited individuals, 1927 (88%) were included in this study. The average age of the participants was 34.2 (±13.8) years, with a majority of 74% being female. Moreover, 68.44% of the participants identified themselves as belonging to the Guarani-Kaiowa ethnic group. HIV seroprevalence was 0.93% (18/1927), and 73.22% (1411/1927) were unaware of their serological status. The prevalence of HIV-1 was higher in single indigenous people [10/617 (1.62%)], who received government benefits [14/1021 (1.37%)], had less than five years of formal education [11/685 (1.61%)], had sexual intercourse with users of injectable drugs [2/21 (9.52%)], with history of sexually transmitted infections (STIs) [10/62 (16.2%)] and incarceration [3/62 (4.84%)]. Of 18 positive samples, 44.4% (8/18) were successfully amplified, and HIV-1 subtype C was prevalent. Furthermore, we identified HIV-1 drug resistance mutations in four patients, specifically from the classes of Protease Inhibitor, Nucleoside Reverse Transcriptase Inhibitor, and Non-Nucleoside Reverse Transcriptase Inhibitor. Notably, three of these patients exhibited a high viral load even after 24 weeks of undergoing antiretroviral therapy. Out of the 18 PLHIV, 66.66% (12/18) had a viral load below 1000 copies/mL, while 50% (9/18) had a CD4+ T lymphocytes count greater than 350 cells/mL after 24 weeks of treatment.

INTERPRETATION

Despite the concerted efforts to control HIV infection, the prevalence observed in the indigenous population under study surpassed that reported in other Brazilian indigenous groups. This disparity highlights the disproportionate impact of the disease on this particular group. The detection of drug-resistance mutations further emphasizes the critical need to expand diagnostic coverage, closely monitor treatment strategies, and maintain ongoing molecular surveillance. These measures are imperative for enhancing HIV management within this vulnerable population.

FUNDING

This study was partially funded by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Apoio ao Desenvolvimento do Ensino, Ciência e Tecnologia do Estado de Mato Grosso do Sul (FUNDECT), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Secretaria do Estado de Saúde (SES) of Governo do Estado de Mato Grosso do Sul, and Universidade Federal da Grande Dourados (UFGD).

Identification of a new circulating recombinant form of human immunodeficiency virus type 1, CRF124_cpx involving subtypes A, G, H, and CRF27_cpx in Angola

Angola, located in Central Africa, has around 320,000 (270,000–380,000) people living with human immunodeficiency virus (HIV)/AIDS, equivalent to 1% of the country’s population at the end of 2021. A previous study conducted in 2012, using Angolan samples collected between 2008 and 2010 revealed a high prevalence of HIV-1 recombinants, around 42% of sequences, with 21% showing the same UH profile in partial pol region which were grouped into a monophyletic cluster with high bootstrap support. Thus, the objective of the present work was to obtain complete genomes of those sequences and characterize them, aiming at a description of a new circulating recombinant form (CRF). Whole blood from nine HIV-1 UH pol-infected individuals had their genomic DNA extracted, and nested PCR was used to amplify seven overlapping fragments targeting the full-length HIV-1 genome. The final classification was based on maximum likelihood trees, and recombination analyses were performed using a bootscan from the Simplot program. BLAST and Los Alamos Database inspections were used to search other similar H-like pol sequences. Complete genome amplification was possible for three samples, partial genomes were obtained for the other three, and only pol was available for the remaining three sequences. Bootscan analysis of the two whole-genome and three partial genome sequences retrieved from people living with HIV/AIDS (PLHIVA) without epidemiological linkage showed the same complex recombination profile involving HIV-1 subtypes A/G/H/CRF27_cpx, with a total of six recombinant breakpoints, aiming to classify a new HIV-1 CRF124_cpx. We found no other full-length HIV-1 genomes with the same mosaic profile; however, we identified 33 partial pol sequences, mainly sampled from Angola between 2001 to 2019, with the same H-like profile. Bayesian analysis of H and H-like pol sequences indicates that CRF124_cpx probably originated in Angola at mid-1970s, indicating that this CRF has been circulating in the country for a long time. In summary, our study describes a new CRF circulating principally in Angola and highlights the importance of continuing molecular surveillance studies, especially in countries with high molecular diversity of HIV.

HIV-1 Diversity and Drug Resistance in Treatment-Naïve Children and Adolescents from Rio de Janeiro, Brazil

The human immunodeficiency virus type 1 (HIV-1) can be transmitted via parenteral, sexual, or vertical exposure routes. The number of HIV-1 cases detected yearly in children and adolescents in Brazil did not decrease over the last decade, representing ~5% of total cases described in the country. In recent years, the HIV-1 diversity and the prevalence of transmitted drug resistance mutations (TDRM) are moving toward a marked increase. In this study, we retrospectively evaluated the diversity of HIV-1 subtypes and the TDRM prevalence in 135 treatment-naïve HIV-1 vertically infected children and adolescents born in between 1993 and 2012. These children were assessed in either 2001–2007 or 2008–2012 when they were 0 to 17 years old. The individuals assessed in 2001–2007 (n = 38) had median CD4+ T cell counts of 1218 cells/mm³ (IQR: 738–2.084) and median HIV-1 plasma viral load of 4.18 log10 copies/mL (IQR: 3.88–4.08). The individuals (n = 97) evaluated in 2008–2012 showed median CD4+ T cell counts of 898.5 cells/mm³ (IQR: 591.3–1.821) and median HIV-1 plasma viral load of 4.69 log10 copies/mL (IQR: 4.26–5.33). A steady decrease in the median CD4 T+ cell counts was observed with age progression, as expected. The majority HIV-1 pol sequences (87%) were classified as pure HIV-1 subtypes (77% subtype B, 9% subtype F1 and 1.5% subtype C), while 13% of sequences were classified as recombinants (CRF45_cpx, n = 4; CRF28/29_BF1, n = 2; CRF02_AG, n = 1; CRF40_BF1, n = 1, CRF99_BF1, n = 1, URF_BF1, n = 8). The overall prevalence of TDRM was 14% (19/135), conferring resistance to the nucleoside reverse transcriptase inhibitors (NRTI, 13/135–9.6%), non-nucleoside reverse transcriptase inhibitors (NNRTI, 8/135–5.9%), and protease inhibitors (PI, 2/135–1.5%). The main TDRM observed for NNRTI was the K103N (n = 8), while the mutations T215I/Y/D/E (n = 7) and M184V (n = 4) were the main TDRM for NRTI. Only two TDRM were observed for PI in one individual each (M46I and V82A). Most TDRM were found in the HIV-1 subtype B (84%) sequences. This study reveals an HIV-1 epidemic with high diversity and moderate prevalence of TDRM in the pediatric population of Rio de Janeiro, indicating the existence of possible problems in the clinical management of prophylactic therapy to prevent mother-to-child transmission and future treatment options for the affected children.

Molecular Epidemiology of HIV-1 among Prisoners in Central Brazil and Evidence of Transmission Clusters

Higher rates of human immunodeficiency virus (HIV) infection have been detected in prisoners when compared with the general population, but research into HIV molecular epidemiology and its transmission network has been lacking among them. Thus, this study aimed to verify potential HIV molecular transmission networks among prisoners. In addition, we aimed to describe the mutations related to antiretroviral resistance in these isolates. Thus, we conducted a cross-sectional survey from 2013 to 2018 in prisons in Central-Western Brazil, and the final sampling composed of 84 prisoners. Proviral DNA was extracted from each whole blood sample followed by amplification of the partial polymerase gene and sequencing. Forty-nine sequences (58.3%) were classified as subtype B, followed by C (14.3%), D, and F1 (2.4% each). A complex and dynamic HIV-1 epidemic is observed in the prisons, as 25% of the sequences were recombinant forms. We detected 15 HIV transmission clusters composed of at least two sequences, that included not only prisoners but also individuals from the general population from the same State with a variety of risk behaviors. Thirty-two percent (32.0%) of treatment-experienced prisoners had at least one drug resistance mutation (DRM), while transmitted DRMs were found in 5.9% of the prisoners. We highlight the urgent need for routine surveillance of HIV-1 infection including resistance genotypic tests considering the high disease burden, risky behaviors inside prisons, and the dynamic relationship of prisoners with the outside community.

HIV-1 molecular diversity in Brazil unveiled by 10 years of sampling by the national genotyping network

HIV-1 has diversified into several subtypes and recombinant forms that are heterogeneously spread around the world. Understanding the distribution of viral variants and their temporal dynamics can help to design vaccines and monitor changes in viral transmission patterns. Brazil has one of the largest HIV-1 epidemics in the western-world and the molecular features of the virus circulating in the country are still not completely known. Over 50,000 partial HIV-1 genomes sampled between 2008 and 2017 by the Brazilian genotyping network (RENAGENO) were analyzed. Sequences were filtered by quality, duplicate sequences per patient were removed and subtyping was performed with online tools and molecular phylogeny. Association between patients’ demographic data and subtypes were performed by calculating the relative risk in a multinomial analysis and trends in subtype prevalence were tested by Pearson correlation. HIV-1B was found to be the most prevalent subtype throughout the country except in the south, where HIV-1C prevails. An increasing trend in the proportion of HIV-1C and F1 was observed in several regions of the country, while HIV-1B tended to decrease. Men and highly educated individuals were more frequently infected by HIV-1B and non-B variants were more prevalent among women with lower education. Our results suggest that socio-demographic factors partially segregate HIV-1 diversity in Brazil while shaping viral transmission networks. Historical events could explain a preferential circulation of HIV-1B among men who have sex with men (MSM) and non-B variants among heterosexual individuals. In view of an increasing male/female ratio of AIDS cases in Brazil in the last 10–15 years, the decrease of HIV-1B prevalence is surprising and suggests a greater penetrance of non-B subtypes in MSM transmission chains.

High Detection Rate of HIV Drug Resistance Mutations among Patients Who Fail Combined Antiretroviral Therapy in Manaus, Brazil

Virologic failure may occur because of poor treatment adherence and/or viral drug resistance mutations (DRM). In Brazil, the northern region exhibits the worst epidemiological scenarios for the human immunodeficiency virus (HIV). Thus, this study is aimed at investigating the genetic diversity of HIV-1 and DRM in Manaus. The cross-sectional study included people living with HIV on combined antiretroviral therapy and who had experienced virological failure during 2018-2019. Sequencing of the protease/reverse transcriptase (PR/RT) and C2V3 of the viral envelope gp120 (Env) regions was analyzed to determine subtypes/variants of HIV-1, DRMs, and tropism. Ninety-two individuals were analyzed in the study. Approximately 72% of them were male and 74% self-declared as heterosexual. Phylogenetic inference (PR/RT-Env) showed that most sequences were B subtype, followed by BF1 or BC mosaic genomes and few F1 and C sequences. Among the variants of subtype B at PR/RT, 84.3% were pandemic (B_PAN), and 15.7% were Caribbean (B_CAR). The DRMs most frequent were M184I/V (82.9%) for nucleoside reverse transcriptase inhibitors (NRTI), K103N/S (63.4%) for nonnucleoside reverse transcriptase inhibitor (NNRTI), and V82A/L/M (7.3%) for protease inhibitors (PI). DRM analysis depicted high levels of resistance for lamivudine and efavirenz in over 82.9% of individuals; although, low (7.7%) cross-resistance to etravirine was observed. A low level of resistance to protease inhibitors was found and included patients that take atazanavir/ritonavir (16.6%) and lopinavir (11.1%), which confirms that these antiretrovirals can be used—for most individuals. The thymidine analog mutations-2 (TAM-2) resistance pathway was higher in B_CAR than in B_PAN. Similar results from other Brazilian studies regarding HIV drug resistance were observed; however, we underscore a need for additional studies regarding subtype B_CAR variants. Molecular epidemiology studies are an important tool for monitoring the prevalence of HIV drug resistance and can influence the public health policies.

Genetic Characteristics of HIV-1 CRF12_BF First Identified in Guangdong Province, China

Multiple HIV-1 genotypes were found circulating in Guangdong Province, China, as this province is located in South China and has a high frequency of international trade. In this study, we report the near full-length genome (NFLG) of CRF12_BF that was identified from a male patient in Guangzhou city, Guangdong Province; this is the first time CRF12_BF has been reported in mainland China. The NFLG was amplified, and then PCR products were sequenced by Sanger sequencing. The CRF12_BF strain was confirmed by the Basic Local Alignment Search Tool and a neighbor-joining phylogenetic tree. In addition, this CRF12_BF strain was confirmed to contain the non-nucleoside reverse transcriptase inhibitor mutation E138A associated with potential low-level resistance against efavirenz and low-level resistance against rilpivirine by the Stanford University HIV Drug Resistance Database program. The analyzed sequence data in this study will provide more information on the HIV epidemic in China.

Prevalence of pretreatment and acquired HIV-1 mutations associated with resistance to lamivudine or rilpivirine: a systematic review

BACKGROUND

Pretreatment and acquired drug resistance mutations (DRMs) can limit antiretroviral therapy effectiveness.

METHODS

We review prevalence of DRMs with resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), focusing on lamivudine and rilpivirine, from 127 articles with >100,000 individuals with HIV-1 infection.

RESULTS

Estimated global prevalence of pretreatment resistance to any NRTI was 4% and to any NNRTI was 6%. Most prevalent DRMs resistant to lamivudine or rilpivirine were at positions E138 (4%), V179 (1%) and M184 (1%). Estimated acquired DRM prevalence was 58% for any NRTIs and 67% for any NNRTIs, most frequently at positions M184 (58%) and Y181 (21%).

CONCLUSIONS

This review suggests low risk of lamivudine- or rilpivirine-resistant mutations in treatment-naive, HIV-1-infected individuals.

Genetic diversity and drug resistance of HIV-1 among infected pregnant women newly diagnosed in Luanda, Angola

Monitoring genetic diversity and drug resistance mutations (DRMs) is critical for understanding HIV epidemiology. Here, we report HIV-1 genetic diversity and DRMs in blood samples from 42 HIV-positive pregnant women naive to antiretroviral therapy (ART), in Luanda. The samples were subjected to nested-PCR, followed by sequencing of HIV-1 pol gene, targeting the protease and reverse transcriptase fragments. HIV-1 diversity was analyzed using the REGA HIV-1 subtyping tool and DRMs were identified using the Calibrated Population Resistance tool. A total of 34 sequences were obtained. The data revealed wide HIV-1 subtypes heterogeneity, with subtype C (38%, 13/34) the most frequent, followed by the subtypes F1 (18%, 6/34), A1 (9%, 3/34), G (9%, 3/34), D (6%, 2/34) and H (3%, 1/34). In addition, recombinants strains were detected, with CRF02_AG (6%, 2/34) the most frequent, followed by CRF37_cpx, F1/C, A1/G and H/G, all with 3% (1/34). A total of 6/34 (18%) of the sequences presented DRMs. The non-nucleoside reverse transcriptase inhibitors presented 15% (5/34) of resistance. Moreover, 1/34 (3%) sequence presented resistance against both non-nucleoside reverse transcriptase inhibitors and nucleoside reverse transcriptase inhibitors, simultaneously. Despite the small sample size, our results suggest the need to update currently used ART regimens. Surveillance of HIV-1 subtypes and DRMs are necessary to understand HIV epidemiology and to guide modification of ART guidelines in Angola.

Human Immunodeficiency Virus Antiretroviral Resistance and Transmission in Mother-Infant Pairs Enrolled in a Large Perinatal Study

Background

The presence of antiretroviral drug-associated resistance mutations (DRMs) may be particularly problematic in human immunodeficiency virus (HIV)-infected pregnant women as it can lead to mother-to-child transmission (MTCT) of resistant HIV strains. This study evaluated the prevalence and the effect of antiretroviral DRMs in previously untreated mother-infant pairs.

Methods

A case-control design of 1:4 (1 transmitter to 4 nontransmitters) was utilized to evaluate DRMs as a predictor of HIV MTCT in specimens obtained from mother-infant pairs. ViroSeq HIV-1 genotyping was performed on mother-infant specimens to assess for clinically relevant DRMs.

Results

One hundred forty infants acquired HIV infection; of these, 123 mother-infant pairs (88%) had specimens successfully amplified using ViroSeq and assessed for drug resistance genotyping. Additionally, 483 of 560 (86%) women who did not transmit HIV to infants also had samples evaluated for DRMs. Sixty-three of 606 (10%) women had clinically relevant DRMs; 12 (2%) had DRMs against >1 drug class. Among 123 HIV-infected infants, 13 (11%) had clinically relevant DRMs, with 3 (2%) harboring DRMs against >1 drug class. In univariate and multivariate analyses, DRMs in mothers were not associated with increased HIV MTCT (adjusted odds ratio, 0.8 [95% confidence interval, .4-1.5]). Presence of DRMs in transmitting mothers was strongly associated with DRM presence in their infants (P < .001).

Conclusions

Preexisting DRMs were common in untreated HIV-infected pregnant women, but did not increase the risk of HIV MTCT. However, if women with DRMs are not virologically suppressed, they may transmit resistant mutations, thus complicating infant management.

HIV-1 Molecular Epidemiology, Transmission Clusters and Transmitted Drug Resistance Mutations in Central Brazil

We aimed to characterize HIV-1 molecular epidemiology and transmission clusters among heterosexual (HET) and men who have sex with men (MSM) individuals, as well as transmitted drug resistance mutations (TDRM) in Central-Western Brazil. This cross-sectional survey was conducted among 190 antiretroviral naïve HIV-1 infected individuals. Proviral DNA was extracted, and nested PCR amplified partial polymerase gene (PR/RT). After sequencing, subtypes were assigned, and the sequences were analyzed for the occurrence of possible transmission networks. Calibrated Population Resistance (CPR) tool from Stanford HIV Database was used to investigate the presence of TDRM. Among 150 individuals whose samples were successfully sequenced, the most prevalent HIV-1 subtype was B, followed by recombinant forms. The occurrence of twenty transmission clusters composed by at least two sequences was verified, suggesting the existence of transmission clusters among individuals from the same or distinct sexual orientations. Intermediate level of TDRM (12%) was found in the study population, and almost half of the subjects with TDRM had more than one resistance mutation. No correlations between sexual orientation and the presence of TDRM, HIV-1 subtypes/recombinants forms were verified. Taken together, the necessity of the continuous monitoring of the TDRM to verify the importance of pre-genotyping and to delineate future strategies in primary antiretroviral therapy. Likewise, the knowledge of the HIV-1 transmission networks in Brazil would allow the implementation of effective HIV-1 prevention strategies in local settings.

HIV-1 genetic diversity and resistance to antiretroviral drugs among pregnant women in Ribeirão Preto (SP), Brazil. Cross-sectional study

BACKGROUND

Increasing genetic diversity of HIV-1 and emergence of drug-resistant mutations may reduce the efficacy of antiretroviral therapy and prophylaxis that are used to prevent mother-to-child transmission. The aim of this study was to assess the genetic diversity and prevalence of drug-resistant mutations among HIV-infected pregnant women.

DESIGN AND SETTING

Cross-sectional study at an outpatient clinic for infectious diseases within gynecology and obstetrics.

METHODS

This study evaluated the dynamics of HIV-1 subtypes and the prevalence of transmitted and acquired drug-resistant mutations among 38 HIV-infected pregnant women (20 previously exposed to antiretroviral therapy and 18 naive), in Ribeirão Preto (SP), Brazil, between 2010 and 2011. Genotyping was performed by means of molecular sequencing of the protease and reverse transcriptase regions of the HIV-1 pol gene.

RESULTS

Subtype B was identified in 84.2% of the samples, recombinant forms between B and F in 7.9%, subtype F1 in 5.3% and the recombinant form K/F in 2.6%. No mutation associated with transmitted drug resistance was detected in the samples from the naive pregnant women, whereas mutations associated with acquired drug resistance were found in 35.0% of the pregnant women previously exposed to antiretroviral therapy.

CONCLUSION

The results showed that subtype B predominated, while there was low prevalence of sequences with transmitted drug resistance.

HIV-1 Genetic Diversity in Northeastern Brazil: High Prevalence of Non-B Subtypes

The Northeastern Brazilian region has experienced a constant increase in the number of newly reported AIDS cases over the last decade, but the genetic diversity of HIV-1 strains currently disseminated in this region remains poorly explored. HIV-1 pol sequences were obtained from 140 patients followed at outpatient clinics from four Northeastern Brazilian states (Alagoas, Bahia, Ceará, and Piauí) between 2014 and 2015. Subtype B was the most prevalent HIV-1 clade (72%) detected in the Northeastern region, followed by subtypes F1 (6%), C (5%), and D (1%). The remaining strains (16%) displayed a recombinant structure and were classified as follows: BF1 (11%), BC (4%), BCF1 (1%), and CRF02_AG like (1%). The 20 HIV-1 BF1 and BC recombinant sequences detected were distributed among 11 lineages classified as follows: CRF28/29_BF like (n = 5), CRF39_BF like (n = 1), URF_BF (n = 9), and URF_BC (n = 5). Non-B subtypes were detected in all Northeastern Brazilian states, but with variable prevalence, ranging from 16% in Ceará to 55% in Alagoas. Phylogenetic analyses support that subtype D and CRF02_AG strains detected in the Northeastern region resulted from the expansion of autochthonous transmission networks, rather than from exogenous introductions from other countries. These results reveal that HIV-1 epidemic spreading in the Northeastern Brazilian region comprised by multiple subtypes and recombinant strains and the molecular epidemiologic pattern in this Brazilian region is much more complex than originally estimated.