Africa-specific human genetic variation near CHD1L associates with HIV-1 load.

HIV-1 remains a global health crisis1, highlighting the need to identify new targets for therapies. Here, given the disproportionate HIV-1 burden and marked human genome diversity in Africa2, we assessed the genetic determinants of control of set-point viral load in 3,879 people of African ancestries living with HIV-1 participating in the international collaboration for the genomics of HIV3. We identify a previously undescribed association signal on chromosome 1 where the peak variant associates with an approximately 0.3 log10-transformed copies per ml lower set-point viral load per minor allele copy and is specific to populations of African descent. The top associated variant is intergenic and lies between a long intergenic non-coding RNA (LINC00624) and the coding gene CHD1L, which encodes a helicase that is involved in DNA repair4. Infection assays in iPS cell-derived macrophages and other immortalized cell lines showed increased HIV-1 replication in CHD1L-knockdown and CHD1L-knockout cells. We provide evidence from population genetic studies that Africa-specific genetic variation near CHD1L associates with HIV replication in vivo. Although experimental studies suggest that CHD1L is able to limit HIV infection in some cell types in vitro, further investigation is required to understand the mechanisms underlying our observations, including any potential indirect effects of CHD1L on HIV spread in vivo that our cell-based assays cannot recapitulate.

Determinants of health-related quality of life in people with Human Immunodeficiency Virus, failing first-line treatment in Africa.

BACKGROUND: Antiretroviral treatment improves health related quality of life (HRQoL) of people with human immunodeficiency virus (PWH). However, one third initiating first-line treatment experience virological failure and the determinants of HRQoL in this key population are unknown. Our study aims to identify determinants of among PWH failing antiretroviral treatment in sub-Saharan Africa. METHODS: We analysed data from a cohort of PWH having virological failure (> 1,000 copies/mL) on first-line ART in South Africa and Uganda. We measured HRQoL using the EuroQOL EQ-5D-3L and used a two-part regression model to obtain by-country analyses for South Africa and Uganda. The first part identifies risk factors that were associated with the likelihood of participants reporting perfect health (utility = 1) versus non-perfect health (utility < 1). The second part identifies risk factors that were associated with the EQ-5 L-3L utility scores for participants reporting non-perfect health. We performed sensitivity analyses to compare the results between the two-part model using tobit models and ordinary least squares regression. RESULTS: In both countries, males were more likely to report perfect health and participants with at least one comorbidity were less likely to report perfect health. In South Africa, participants with side effects and in Uganda those with opportunistic infections were also less likely to report perfect health. In Uganda, participants with 100% ART adherence were more likely to report perfect health. In South Africa, high HIV viral load, experiencing ART side effects, and the presence of opportunistic infections were each associated with lower HRQoL, whereas participants with 100% ART adherence reported higher HRQoL. In Uganda participants with lower CD4 count had lower HRQoL. CONCLUSION: Markers of advanced disease (opportunistic infection, high viral load, low CD4), side effects, comorbidities and lack of ART adherence negatively impacted HRQoL for PWH experiencing virological failure. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02787499.

Affordable drug resistance genotyping of HIV-1 reverse transcriptase, protease and integrase genes, for resource limited settings.

BACKGROUND: As use of dolutegravir (DTG) becomes more common in resource limited settings (RLS), the demand for integrase resistance testing is increasing. Affordable methods for genotyping all relevant HIV-1 pol genes (i.e., protease (PR), reverse transcriptase (RT) and integrase (IN)) are required to guide choice of future antiretroviral therapy (ART). We designed an in-house HIV-1 drug resistance (HIVDR) genotyping method that is affordable and suitable for use in RLS. METHODS: We obtained remnant plasma samples from CAPRISA 103 study and amplified HIV-1 PR, RT and IN genes, using an innovative PCR assay. We validated the assay using remnant plasma samples from an external quality assessment (EQA) programme. We genotyped samples by Sanger sequencing and assessed HIVDR mutations using the Stanford HIV drug resistance database. We compared drug resistance mutations with previous genotypes and calculated method cost-estimates. RESULTS: From 96 samples processed, we obtained sequence data for 78 (81%), of which 75 (96%) had a least one HIVDR mutation, with no major-IN mutations observed. Only one sample had an E157Q INSTI-accessory mutation. When compared to previous genotypes, 18/78 (23%) had at least one discordant mutation, but only 2/78 (3%) resulted in different phenotypic predictions that could affect choice of subsequent regimen. All CAPRISA 103 study sequences were HIV-1C as confirmed by phylogenetic analysis. Of the 7 EQA samples, 4 were HIV-1C, 2 were HIV-1D, and 1 was HIV-1A. Genotypic resistance data generated using the IDR method were 100% concordant with EQA panel results. Overall genotyping cost per sample was estimated at ~ US$43-$US49, with a processing time of ~ 2 working days. CONCLUSIONS: We successfully designed an in-house HIVDR method that is suitable for genotyping HIV-1 PR, RT and IN genes, at an affordable cost and shorter turnaround time. This HIVDR genotyping method accommodates changes in ART regimens and will help to guide HIV-1 treatment decisions in RLS.

Comparing effectiveness of first-line antiretroviral therapy between peri-urban and rural clinics in KwaZulu-Natal, South Africa.

OBJECTIVES: Viral suppression (VS) is the hallmark of successful antiretroviral therapy (ART) programmes. We sought to compare clinic retention, virological outcomes, drug resistance and mortality between peri-urban and rural settings in South Africa after first-line ART. METHODS: Beginning in July 2014, 1000 (500 peri-urban and 500 rural) ART-naïve patients with HIV were enrolled and managed according to local standard of care. Clinic retention, virological suppression, virological failure (VF), genotypic drug resistance and mortality were assessed. The definition of VS was a viral load ≤1000 copies/ml. Time to event analyses were stratified by site, median age and gender. Kaplan-Meier curves were calculated and graphed with log-rank modelling to compare curves. RESULTS: Based on 2741 patient-years of follow-up, retention and mortality did not differ between sites. Among all 1000 participants, 47%, 84% and 91% had achieved VS by 6, 12 and 24 months, respectively, which was observed earlier in the peri-urban site. At both sites, men aged < 32 years had the highest proportion of VF (15.5%), while women aged > 32 years had the lowest, at 7.1% (p = 0.018). Among 55 genotypes, 42 (76.4%) had at one or more resistance mutations, which did not differ by site. K103N (59%) and M184V (52%) were the most common mutations, followed by V106M and K65R (31% each). Overall, death was infrequent (< 4%). CONCLUSIONS: No significant differences in treatment outcomes between peri-urban and rural clinics were observed. In both settings, young men were especially susceptible to clinic attrition and VF. More effective adherence support for this important demographic group is needed to achieve UNAIDS targets.

Who's slipping through the cracks? A comprehensive individual, clinical and health system characterization of people with virological failure on first-line HIV treatment in Uganda and South Africa.

OBJECTIVES: HIV virological failure remains a major threat to programme success in sub-Saharan Africa. While HIV drug resistance (HIVDR) and inadequate adherence are the main drivers of virological failure, the individual, clinical and health system characteristics that lead to poor outcomes are not well understood. The objective of this paper is to identify those characteristics among people failing first-line antiretroviral therapy (ART). METHODS: We enrolled a cohort of adults in HIV care experiencing virological failure on first-line ART at five sites and used standard statistical methods to characterize them with a focus on three domains: individual/demographic, clinical, and health system, and compared each by country of enrolment. RESULTS: Of 840 participants, 51% were women, the median duration on ART was 3.2 years [interquartile range (IQR) 1.1, 6.4 years] and the median CD4 cell count prior to failure was 281 cells/µL (IQR 121, 457 cells/µL). More than half of participants [53%; 95% confidence interval (CI) 49-56%] stated that they had > 90% adherence and 75% (95% CI 72-77%) took their ART on time all or most of the time. Conversely, the vast majority (90%; 95% CI 86-92%) with a completed genotypic drug resistance test had any HIV drug resistance. This population had high health system use, reporting a median of 3 (IQR 2.6) health care visits and a median of 1 (IQR 1.1) hospitalization in the preceding 6 months. CONCLUSIONS: Patients failing first-line ART in sub-Saharan Africa generally report high rates of adherence to ART, have extremely high rates of HIV drug resistance and utilize significant health care resources. Health systems interventions to promptly detect and manage treatment failure will be a prerequisite to establishing control of the HIV epidemic.

HIV infection and anaemia do not affect HbA1c for the detection of diabetes in black South Africans: Evidence from the Durban Diabetes Study.

OBJECTIVE: South Africa has a high burden of HIV infection and anaemia. These conditions may cause HbA1c to over- or underestimate glycaemia; however, this has not been comprehensively investigated in African populations. We assessed the association of anaemia, HIV infection and antiretroviral therapy (ART) with HbA1c , and implications for the detection and diagnosis of diabetes, in a black South African population. RESEARCH DESIGN AND METHODS: In this population-based cross-sectional study in eThekwini municipality (Durban), South Africa, we assessed HbA1c and conducted oral glucose tolerance tests (OGTTs), HIV diagnostic tests and full blood count measurements among 1067 participants without a history of diabetes diagnosis. Linear regression was used to examine differences in HbA1c by anaemia (comparator: no anaemia), or HIV and ART (comparator: no HIV) status. HbA1c -based diabetes prevalence was compared with OGTT-based prevalence among individuals with anaemia and with untreated and ART-treated HIV. RESULTS: In adjusted analyses, normocytic and microcytic anaemia were associated with higher HbA1c compared with no anaemia, whereas macrocytic anaemia and ART-treated HIV were associated with lower HbA1c compared with no anaemia and no HIV, respectively. However, magnitudes of association were small (range: ß  = -3.4 mmol/mol or -0.31%, p < 0.001 [macrocytic anaemia] to ß = 2.1 mmol/mol or 0.19%, p < 0.001 [microcytic anaemia]). There was no significant difference in diabetes prevalence based on HbA1c or OGTT among individuals with anaemia (2.9% vs. 3.3%, p = 0.69), untreated HIV (1.6% vs. 1.6% p = 1.00) or ART-treated HIV (2.9% vs. 1.2%, p = 0.08). CONCLUSIONS: Our results suggest that anaemia and HIV status appear unlikely to materially affect the utility of HbA1c for diabetes detection and diagnosis in this population. Further studies are needed to examine these associations in sub-Saharan African populations.

Acquired HIV drug resistance and virologic monitoring in a HIV hyper-endemic setting in KwaZulu-Natal Province, South Africa.

BACKGROUND: Introduction of tenofovir (TDF) plus lamivudine (3TC) and dolutegravir (DTG) in first- and second-line HIV treatment regimens in South Africa warrants characterization of acquired HIV-1 drug resistance (ADR) mutations that could impact DTG-based antiretroviral therapy (ART). In this study, we sought to determine prevalence of ADR mutations and their potential impact on susceptibility to drugs used in combination with DTG among HIV-positive adults (≥ 18 years) accessing routine care at a selected ART facility in KwaZulu-Natal, South Africa. METHODS: We enrolled adult participants in a cross-sectional study between May and September 2019. Eligible participants had a most recent documented viral load (VL) ≥ 1000 copies/mL after at least 6 months on ART. We genotyped HIV-1 reverse transcriptase and protease genes by Sanger sequencing and assessed ADR. We characterized the effect of ADR mutations on the predicted susceptibility to drugs used in combination with DTG. RESULTS: From 143 participants enrolled, we obtained sequence data for 115 (80%), and 92.2% (95% CI 85.7-96.4) had ADR. The proportion with ADR was similar for participants on first-line ART (65/70, 92.9%, 95% CI 84.1-97.6) and those on second-line ART (40/44, 90.9%, 95% CI 78.3-97.5), and was present for the single participant on third-line ART. Approximately 89% (62/70) of those on first-line ART had dual class NRTI and NNRTI resistance and only six (13.6%) of those on second-line ART had major PI mutations. Most participants (82%) with first-line viraemia maintained susceptibility to Zidovudine (AZT), and the majority of them had lost susceptibility to TDF (71%) and 3TC (84%). Approximately two in every five TDF-treated individuals had thymidine analogue mutations (TAMs). CONCLUSIONS: Susceptibility to AZT among most participants with first-line viraemia suggests that a new second-line regimen of AZT + 3TC + DTG could be effective. However, atypical occurrence of TAMs in TDF-treated individuals suggests a less effective AZT + 3TC + DTG regimen in a subpopulation of patients. As most patients with first-line viraemia had at least low-level resistance to TDF and 3TC, identifying viraemia before switch to TDF + 3TC + DTG is important to avoid DTG functional monotherapy. These findings highlight a need for close monitoring of outcomes on new standardized treatment regimens.

Social Mixing and Clinical Features Linked With Transmission in a Network of Extensively Drug-resistant Tuberculosis Cases in KwaZulu-Natal, South Africa.

BACKGROUND: Tuberculosis (TB) is the leading infectious cause of death globally, and drug-resistant TB strains pose a serious threat to controlling the global TB epidemic. The clinical features, locations, and social factors driving transmission in settings with high incidences of drug-resistant TB are poorly understood. METHODS: We measured a network of genomic links using Mycobacterium tuberculosis whole-genome sequences. RESULTS: Patients with 2-3 months of cough or who spent time in urban locations were more likely to be linked in the network, while patients with sputum smear-positive disease were less likely to be linked than those with smear-negative disease. Associations persisted using different thresholds to define genomic links and irrespective of assumptions about the direction of transmission. CONCLUSIONS: Identifying factors that lead to many transmissions, including contact with urban areas, can suggest settings instrumental in transmission and indicate optimal locations and groups to target with interventions.

Modeling Missing Cases and Transmission Links in Networks of Extensively Drug-Resistant Tuberculosis in KwaZulu-Natal, South Africa.

Patterns of transmission of drug-resistant tuberculosis (TB) remain poorly understood, despite over half a million incident cases worldwide in 2017. Modeling TB transmission networks can provide insight into drivers of transmission, but incomplete sampling of TB cases can pose challenges for inference from individual epidemiologic and molecular data. We assessed the effect of missing cases on a transmission network inferred from Mycobacterium tuberculosis sequencing data on extensively drug-resistant TB cases in KwaZulu-Natal, South Africa, diagnosed in 2011-2014. We tested scenarios in which cases were missing at random, missing differentially by clinical characteristics, or missing differentially by transmission (i.e., cases with many links were under- or oversampled). Under the assumption that cases were missing randomly, the mean number of transmissions per case in the complete network needed to be larger than 20, far higher than expected, to reproduce the observed network. Instead, the most likely scenario involved undersampling of high-transmitting cases, and models provided evidence for super-spreading. To our knowledge, this is the first analysis to have assessed support for different mechanisms of missingness in a TB transmission study, but our results are subject to the distributional assumptions of the network models we used. Transmission studies should consider the potential biases introduced by incomplete sampling and identify host, pathogen, or environmental factors driving super-spreading.

Transmission of Extensively Drug-Resistant Tuberculosis in South Africa.

BACKGROUND: Drug-resistant tuberculosis threatens recent gains in the treatment of tuberculosis and human immunodeficiency virus (HIV) infection worldwide. A widespread epidemic of extensively drug-resistant (XDR) tuberculosis is occurring in South Africa, where cases have increased substantially since 2002. The factors driving this rapid increase have not been fully elucidated, but such knowledge is needed to guide public health interventions. METHODS: We conducted a prospective study involving 404 participants in KwaZulu-Natal Province, South Africa, with a diagnosis of XDR tuberculosis between 2011 and 2014. Interviews and medical-record reviews were used to elicit information on the participants' history of tuberculosis and HIV infection, hospitalizations, and social networks. Mycobacterium tuberculosis isolates underwent insertion sequence (IS)6110 restriction-fragment-length polymorphism analysis, targeted gene sequencing, and whole-genome sequencing. We used clinical and genotypic case definitions to calculate the proportion of cases of XDR tuberculosis that were due to inadequate treatment of multidrug-resistant (MDR) tuberculosis (i.e., acquired resistance) versus those that were due to transmission (i.e., transmitted resistance). We used social-network analysis to identify community and hospital locations of transmission. RESULTS: Of the 404 participants, 311 (77%) had HIV infection; the median CD4+ count was 340 cells per cubic millimeter (interquartile range, 117 to 431). A total of 280 participants (69%) had never received treatment for MDR tuberculosis. Genotypic analysis in 386 participants revealed that 323 (84%) belonged to 1 of 31 clusters. Clusters ranged from 2 to 14 participants, except for 1 large cluster of 212 participants (55%) with a LAM4/KZN strain. Person-to-person or hospital-based epidemiologic links were identified in 123 of 404 participants (30%). CONCLUSIONS: The majority of cases of XDR tuberculosis in KwaZulu-Natal, South Africa, an area with a high tuberculosis burden, were probably due to transmission rather than to inadequate treatment of MDR tuberculosis. These data suggest that control of the epidemic of drug-resistant tuberculosis requires an increased focus on interrupting transmission. (Funded by the National Institute of Allergy and Infectious Diseases and others.).

Impact of pretreatment low-abundance HIV-1 drug-resistant variants on virological failure among HIV-1/TB-co-infected individuals.

OBJECTIVES: To determine the impact of pretreatment low-abundance HIV-1 drug-resistant variants (LA-DRVs) on virological failure (VF) among HIV-1/TB-co-infected individuals treated with NNRTI first-line ART. METHODS: We conducted a case-control study of 170 adults with HIV-1/TB co-infection. Cases had at least one viral load (VL) ≥1000 RNA copies/mL after ≥6 months on NNRTI-based ART, and controls had sustained VLs <1000 copies/mL. We sequenced plasma viruses by Sanger and MiSeq next-generation sequencing (NGS). We assessed drug resistance mutations (DRMs) using the Stanford drug resistance database, and analysed NGS data for DRMs at ≥20%, 10%, 5% and 2% thresholds. We assessed the effect of pretreatment drug resistance (PDR) on VF. RESULTS: We analysed sequences from 45 cases and 125 controls. Overall prevalence of PDR detected at a ≥20% threshold was 4.7% (8/170) and was higher in cases than in controls (8.9% versus 3.2%), P = 0.210. Participants with PDR at ≥20% had almost 4-fold higher odds of VF (adjusted OR 3.7, 95% CI 0.8-18.3) compared with those without, P = 0.104. PDR prevalence increased to 18.2% (31/170) when LA-DRVs at ≥2% were included. Participants with pretreatment LA-DRVs only had 1.6-fold higher odds of VF (adjusted OR 1.6, 95% CI 0.6-4.3) compared with those without, P = 0.398. CONCLUSIONS: Pretreatment DRMs and LA-DRVs increased the odds of developing VF on NNRTI-based ART, although without statistical significance. NGS increased detection of DRMs but provided no additional benefit in identifying participants at risk of VF at lower thresholds. More studies assessing mutation thresholds predictive of VF are required to inform use of NGS in treatment decisions.

Congenital Rubella Syndrome Surveillance in South Africa Using a Sentinel Site Approach: A Cross-sectional Study.

BACKGROUND: Congenital rubella syndrome (CRS) includes disorders associated with intrauterine rubella infection. Incidence of CRS is higher in countries with no rubella-containing vaccines (RCV) in their immunization schedules. In the World Health Organization African region, RCVs are being introduced as part of the 2012-2020 global measles and rubella strategic plan. This study aimed to describe the epidemiology of confirmed CRS in South Africa prior to introduction of RCVs in the immunization schedule. METHODS: This was a descriptive study with 28 sentinel sites reporting laboratory-confirmed CRS cases in all 9 provinces of South Africa. In the retrospective phase (2010 to 2014), CRS cases were retrieved from medical records, and in the prospective phase (2015 to 2017) clinicians at study sites reported CRS cases monthly. RESULTS: There were 42 confirmed CRS cases in the retrospective phase and 53 confirmed CRS cases in the prospective phase. Most frequently reported birth defects were congenital heart disease and cataracts. The median age of mothers of CRS cases was 21 years in the retrospective phase (range: 11 to 38 years) and 22 years in the prospective phase (range: 15 to 38 years). CONCLUSION: Baseline data on laboratory-confirmed CRS will enable planning and monitoring of RCV implementation in the South African Expanded Programme on Immunization program. Ninety-eight percent of mothers of infants with CRS were young women 14-30 years old, indicating a potential immunity gap in this age group for consideration during introduction of RCV.

Parvovirus B19 in South African blood donors.

BACKGROUND: Parvovirus B19 (PVB19) is transmitted via transfusion of blood and blood products. PVB19 is resistant to viral inactivation methods, which poses a threat to blood safety. We investigated the prevalence of PVB19 antibodies and DNA in healthy blood donors from the South African National Blood Bank Service to evaluate the necessity of PVB19 DNA testing. STUDY DESIGN AND METHOD: A retrospective analysis of 1500 residual plasma specimens from healthy blood donors from the SANBS repository were screened in mini-pools of 20 for PVB19 DNA using a quantitative polymerase chain reaction (PCR). Positive pools were resolved by individual viral load testing and screened for PVB19 immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies to correlate viral loads with serological status. PVB19 IgG prevalence was determined by testing 90 randomly selected specimens from the 1500 plasma specimens. RESULTS: The prevalence of PVB19 IgG, IgM and IgG, and DNA was 62.2%, 0.06%, and 0.9%, respectively. Fourteen of the 1500 blood donor specimens received, had detectable PVB19 viral loads. Nine of the fourteen donors with detectable viral loads were PVB19 IgG seropositive. The PVB19 viral loads ranged from 1.81 to 5.32 log IU/mL. Four of the fourteen viraemic donors had a viraemia >10 4 IU/mL. CONCLUSION: We have demonstrated a low prevalence of PVB19 DNA in SANBS blood donors. The predominance of low-level viraemia and the presence of PVB19 antibodies, suggests that the risk of transfusion transmission of PVB19 among SANBS donors may be relatively low.

Spatial Patterns of Extensively Drug-Resistant Tuberculosis Transmission in KwaZulu-Natal, South Africa.

Background: Transmission is driving the global drug-resistant tuberculosis (TB) epidemic; nearly three-quarters of drug-resistant TB cases are attributable to transmission. Geographic patterns of disease incidence, combined with information on probable transmission links, can define the spatial scale of transmission and generate hypotheses about factors driving transmission patterns. Methods: We combined whole-genome sequencing data with home Global Positioning System coordinates from 344 participants with extensively drug-resistant (XDR) TB in KwaZulu-Natal, South Africa, diagnosed from 2011 to 2014. We aimed to determine if genomically linked (difference of ≤5 single-nucleotide polymorphisms) cases lived close to one another, which would suggest a role for local community settings in transmission. Results: One hundred eighty-two study participants were genomically linked, comprising 1084 case-pairs. The median distance between case-pairs' homes was 108 km (interquartile range, 64-162 km). Between-district, as compared to within-district, links accounted for the majority (912/1084 [84%]) of genomic links. Half (526 [49%]) of genomic links involved a case from Durban, the urban center of KwaZulu-Natal. Conclusions: The high proportions of between-district links with Durban provide insight into possible drivers of province-wide XDR-TB transmission, including urban-rural migration. Further research should focus on characterizing the contribution of these drivers to overall XDR-TB transmission in KwaZulu-Natal to inform design of targeted strategies to curb the drug-resistant TB epidemic.

Improved Survival and Cure Rates With Concurrent Treatment for Multidrug-Resistant Tuberculosis-Human Immunodeficiency Virus Coinfection in South Africa.

Background: Mortality in multidrug-resistant (MDR) tuberculosis-human immunodeficiency virus (HIV) coinfection has historically been high, but most studies predated the availability of antiretroviral therapy (ART). We prospectively compared survival and treatment outcomes in MDR tuberculosis-HIV-coinfected patients on ART to those in patients with MDR tuberculosis alone. Methods: This observational study enrolled culture-confirmed MDR tuberculosis patients with and without HIV in South Africa between 2011 and 2013. Participants received standardized MDR tuberculosis and HIV regimens and were followed monthly for treatment response, adverse events, and adherence. The primary outcome was survival. Results: Among 206 participants, 150 were HIV infected, 131 (64%) were female, and the median age was 33 years (interquartile range [IQR], 26-41). Of the 191 participants with a final MDR tuberculosis outcome, 130 (73%) were cured or completed treatment, which did not differ by HIV status (P = .50). After 2 years, CD4 count increased a median of 140 cells/mm3 (P = .005), and 64% had an undetectable HIV viral load. HIV-infected and HIV-uninfected participants had high rates of survival (86% and 94%, respectively; P = .34). The strongest risk factor for mortality was having a CD4 count ≤100 cells/mm3 (adjusted hazards ratio, 15.6; 95% confidence interval, 4.4-55.6). Conclusions: Survival and treatment outcomes among MDR tuberculosis-HIV individuals receiving concurrent ART approached those of HIV-uninfected patients. The greatest risk of death was among HIV-infected individuals with CD4 counts ≤100 cells/mm3. These findings provide critical evidence to support concurrent treatment of MDR tuberculosis and HIV.

Extensively drug-resistant tuberculosis in South Africa: genomic evidence supporting transmission in communities.

Despite evidence that transmission is driving an extensively drug-resistant TB (XDR-TB) epidemic, our understanding of where and between whom transmission occurs is limited. We sought to determine whether there was genomic evidence of transmission between individuals without an epidemiologic connection.We conducted a prospective study of XDR-TB patients in KwaZulu-Natal, South Africa, during the 2011-2014 period. We collected sociodemographic and clinical data, and identified epidemiologic links based on person-to-person or hospital-based connections. We performed whole-genome sequencing (WGS) on the Mycobacterium tuberculosis isolates and determined pairwise single nucleotide polymorphism (SNP) differences.Among 404 participants, 123 (30%) had person-to-person or hospital-based links, leaving 281 (70%) epidemiologically unlinked. The median SNP difference between participants with person-to-person and hospital-based links was 10 (interquartile range (IQR) 8-24) and 16 (IQR 10-23), respectively. The median SNP difference between unlinked participants and their closest genomic link was 5 (IQR 3-9) and half of unlinked participants were within 7 SNPs of at least five participants.The majority of epidemiologically-unlinked XDR-TB patients had low pairwise SNP differences with at least one other participant, consistent with transmission. These data suggest that much of transmission may result from casual contact in community settings between individuals not known to one another.

pncA Gene Mutations Associated with Pyrazinamide Resistance in Drug-Resistant Tuberculosis, South Africa and Georgia.

Although pyrazinamide is commonly used for tuberculosis treatment, drug-susceptibility testing is not routinely available. We found polymorphisms in the pncA gene for 70% of multidrug-resistant and 96% of extensively drug-resistant Mycobacterium tuberculosis isolates from South Africa and Georgia. Assessment of pyrazinamide susceptibility may be prudent before using it in regimens for drug-resistant tuberculosis.

Rates of virological suppression and drug resistance in adult HIV-1-positive patients attending primary healthcare facilities in KwaZulu-Natal, South Africa.

BACKGROUND: KwaZulu-Natal (KZN) Province in South Africa has the highest HIV disease burden in the country, with an estimated population prevalence of 24.7%. A pilot sentinel surveillance project was undertaken in KZN to classify the proportion of adult patients failing first-line ART and to describe the patterns of drug resistance mutations (DRMs) in patients with virological failure (VF). METHODS: Cross-sectional surveillance of acquired HIV drug resistance was conducted in 15 sentinel ART clinics between August and November 2013. Two population groups were surveyed: on ART for 12-15 months (Cohort A) or 24-36 months (Cohort B). Plasma specimens with viral load ≥1000 copies/mL were defined as VF and genotyped for DRMs. RESULTS: A total of 1299 adults were included in the analysis. The prevalence of VF was 4.0% (95% CI 1.8-8.8) among 540 adults in Cohort A and 7.7% (95% CI 4.4-13.0) of 759 adults in Cohort B. Treatment with efavirenz was more likely to suppress viral load in Cohort A (P = 0.005). Independent predictors of VF for Cohort B included male gender, advanced WHO stage at ART initiation and treatment with stavudine or zidovudine compared with tenofovir. DRMs were detected in 89% of 123 specimens with VF, including M184I/V, K103N/S, K65N/R, V106A/M and Y181C. CONCLUSIONS: VF in adults in KZN was <8% up to 3 years post-ART initiation but was associated with a high frequency of DRMs. These data identify key groups for intensified adherence counselling and highlight the need to optimize first-line regimens to maintain viral suppression.

A post-partum single-dose TDF/FTC tail does not prevent the selection of NNRTI resistance in women receiving pre-partum ZDV and intrapartum single-dose nevirapine to prevent mother-to- child HIV-1 transmission.

Although the rates of vertical transmission of HIV in the developing world have improved to around 3% in countries like South Africa, resistance to antiretrovirals (ARV) used in Prevention of Mother-to-Child transmission (pMTCT) strategies may thwart such outcomes and affect the efficacy of future ARV regimens in mothers and children. This study conducted in Durban, South Africa, between 2010 and 2013 found a high rate of nevirapine (NVP) resistance among women receiving Zidovudine (AZT) from 14 weeks gestation, single dose nevirapine (sd NVP) at the onset of labor and a single dose of coformulated Tenofovir/Emtricitabine (TDF/FTC) postpartum. Using Sanger sequencing, high and intermediate levels of nevirapine (NVP) resistance were detected in 15/44 (34%) and in 1/44 (2%) of women tested, respectively. Most subjects selected the K103N mutation (22% (10/45) of all patients and 66% (10/15) of those with high-level NVP resistance). Such rate of NVP resistance is comparable to studies where only sd NVP was used. In conclusion, a post-partum single-dose TDF/FTC tail does not prevent the selection of NNRTI resistance in women receiving pre-partum ZDV and intrapartum sd NVP to prevent mother-to-child HIV-1 transmission.