Detection of K103N in Ugandan women after repeated exposure to single dose nevirapine.

OBJECTIVES: Use of single dose nevirapine (SD NVP) for prevention of HIV-1 mother-to-child transmission (pMTCT) is associated with selection of K103N-containing HIV variants. Repeat use of SD NVP for pMTCT may influence emergence and persistence of NVP-resistant variants. DESIGN: K103N-containing variants were studied in 48 Ugandan women who received SD NVP in the HIVNET 012 trial, and were re-exposed to SD NVP in one (n = 44) or two (n = 4) subsequent pregnancies during a 5-year follow-up study. METHODS: Samples were analyzed using the LigAmp assay (assay cutoff: 0.5% K103N). RESULTS: Among 44 women who were re-exposed to SD NVP in one subsequent pregnancy, 37.8% had K103N detected within 1 year of SD-NVP re-exposure. Detection of K103N was independently associated with detection of K103N 6-8 weeks after the first SD NVP exposure and with pre-NVP viral load. The portion of women with undetectable K103N by 2 years after SD NVP administration was similar after first versus second use of SD NVP for pMTCT. K103N was undetectable in 93.2% of evaluable women by 3 years of re-exposure. Only two of four women who received SD NVP in two pregnancies during the follow-up study had K103N detected after the last SD NVP exposure. CONCLUSIONS: K103N was detected in some women within 1 year of SD NVP re-exposure, but faded from detection in most women by 3 years after re-exposure. Detection of K103N by 1 year after SD NVP re-exposure was associated with prior selection of K103N-containing variants and with pre-NVP viral load.

Sensitivity of the ViroSeq HIV-1 genotyping system for detection of the K103N resistance mutation in HIV-1 subtypes A, C, and D.

The US Food and Drug Administration-cleared ViroSeq HIV-1 Genotyping System (ViroSeq) and other population sequencing-based human immunodeficiency virus type 1 (HIV-1) genotyping methods detect antiretroviral drug resistance mutations present in the major viral population of a test sample. These assays also detect some mutations in viral variants that are present as mixtures. We compared detection of the K103N nevirapine resistance mutation using ViroSeq and a sensitive, quantitative point mutation assay, LigAmp. The LigAmp assay measured the percentage of K103N-containing variants in the viral population (percentage of K103N). We analyzed 305 samples with HIV-1 subtypes A, C, and D collected from African women after nevirapine administration. ViroSeq detected K103N in 100% of samples with >20% K103N, 77.8% of samples with 10 to 20% K103N, 71.4% of samples with 5 to 10% K103N, and 16.9% of samples with 1 to 5% K103N. The sensitivity of ViroSeq for detection of K103N was similar for subtypes A, C, and D. These data indicate that the ViroSeq system reliably detects the K103N mutation at levels above 20% and frequently detects the mutation at lower levels. Further studies are needed to compare the sensitivity of different assays for detection of HIV-1 drug resistance mutations and to determine the clinical relevance of HIV-1 minority variants.

Analysis of insertions and deletions in the gag p6 region of diverse HIV type 1 strains.

Sequence variation in the gag p6 region in subtype B HIV-1 has been associated with changes in viral replication capacity and antiretroviral drug susceptibility. We examined sequence variation in the HIV-1 gag p6 region using plasma samples from 22 individuals with non-subtype B HIV-1 infection [subtypes A, C, D, F, and G, and circulating recombinant forms (CRFs) CRF01-AE and CRF02_AG]. An additional 105 gag sequences from the Los Alamos National Laboratory database were also analyzed. Extensive length variation was observed in the p6 gag region. Specific patterns of insertions and deletions were observed in different subtypes and CRFs, and no two subtypes or CRFs had the same general pattern. PTAP duplications were more common in subtype C than other strains (3 of 14 in subtype C vs. 2 of 113 in other strains, p = 0.004), and KQE duplications were seen only in subtype B. Further studies are needed to determine whether such genotypic differences influence viral replication capacity, antiretroviral drug susceptibility, or other phenotypic properties of these strains.

Cell phone utilization among foreign-born Latinos: a promising tool for dissemination of health and HIV information.

Latinos in the US are disproportionately affected by HIV and are at risk for late presentation to care. Between June 2011 and January 2012, we conducted a cross-sectional survey of 209 Baltimore Latinos at community-based venues to evaluate the feasibility of using information communication technology-based interventions to improve access to HIV testing and education within the Spanish-speaking community in Baltimore. Participants had a median age of 33 years interquartile range (IQR) (IQR 28-42), 51.7 % were male, and 95.7 % were foreign-born. Approximately two-thirds (63.2 %) had been in the US less than 10 years and 70.1 % had been previously tested for HIV. Cell phone (92.3 %) and text messaging (74.2 %) was used more than Internet (52.2 %) or e-mail (42.8 %) (p < 0.01). In multivariate analysis, older age and lower education were associated with less utilization of Internet, e-mail and text messaging, but not cell phones. Interest was high for receiving health education (73.1 %), HIV education (70.2 %), and test results (68.8 %) via text messaging. Innovative cell phone-based communication interventions have the potential to link Latino migrants to HIV prevention, testing and treatment services.

A novel educational strategy targeting health care workers in underserved communities in Central America to integrate HIV into primary medical care.

BACKGROUND: Current educational strategies to integrate HIV care into primary medical care in Central America have traditionally targeted managers or higher-level officials, rather than local health care workers (HCWs). We developed a complementary online and on-site interactive training program to reach local HCWs at the primary care level in underserved communities. METHODS: The training program targeted physicians, nurses, and community HCWs with limited access to traditional onsite training in Panama, Nicaragua, Dominican Republic, and Guatemala. The curriculum focused on principles of HIV care and health systems using a tutor-supported blended educational approach of an 8-week online component, a weeklong on-site problem-solving workshop, and individualized project-based interventions. RESULTS: Of 258 initially active participants, 225 (225/258=87.2%) successfully completed the online component and the top 200 were invited to the on-site workshop. Of those, 170 (170/200=85%) attended the on-site workshop. In total, 142 completed all three components, including the project phase. Quantitative and qualitative evaluation instruments included knowledge assessments, reflexive essays, and acceptability surveys. The mean pre and post-essay scores demonstrating understanding of social determinants, health system organization, and integration of HIV services were 70% and 87.5%, respectively, with an increase in knowledge of 17.2% (p<0.001). The mean pre- and post-test scores evaluating clinical knowledge were 70.9% and 90.3%, respectively, with an increase in knowledge of 19.4% (p<0.001). A survey of Likert scale and open-ended questions demonstrated overwhelming participant satisfaction with course content, structure, and effectiveness in improving their HIV-related knowledge and skills. CONCLUSION: This innovative curriculum utilized technology to target HCWs with limited access to educational resources. Participants benefited from technical skills acquired through the process, and could continue working within their underserved communities while participating in the online component and then implement interventions that successfully converted theoretical knowledge to action to improve integration of HIV care into primary care.

Nevirapine resistance in women and infants after first versus repeated use of single-dose nevirapine for prevention of HIV-1 vertical transmission.

Single-dose (SD) nevirapine (NVP) significantly reduces mother-to-child transmission of human immunodeficiency virus (HIV). We analyzed NVP resistance after receipt of SD NVP in 57 previously SD NVP-naive women, in 34 SD NVP-experienced women, and in 17 HIV-infected infants. The proportion of women infected with variants with resistance mutations, the types of mutations detected, and the frequency and level of K103N were similar in the two groups of women at 6 weeks and 6 months post partum. NVP resistance was detected in a similar proportion of infants born to SD NVP-naive versus SD NVP-experienced women. Repeated use of SD NVP to prevent HIV transmission does not appear to influence NVP resistance.

Persistence of K103N-containing HIV-1 variants after single-dose nevirapine for prevention of HIV-1 mother-to-child transmission.

K103N-containing human immunodeficiency virus (HIV)-1 variants are selected in some women who receive single-dose (SD) nevirapine (NVP) for prevention of HIV-1 mother-infant transmission. We examined the persistence of K103N in women who received SD NVP prophylaxis. K103N was detected using the LigAmp assay (assay cutoff, 0.5% K103N). K103N was detected at 6-8 weeks in 60 (41.7%) of 144 women. Fading (lack of detection) of K103N was documented in 16 women by 2 years, 43 women by 3 years, and 55 women by 4 and 5 years. Slower fading was independently associated with HIV-1 subtype (D>A) and higher pre-NVP viral load.

Quantitative analysis of HIV-1 variants with the K103N resistance mutation after single-dose nevirapine in women with HIV-1 subtypes A, C, and D.

INTRODUCTION: We used a sensitive point mutation assay, LigAmp, to detect and quantify K103N-containing variants in African women who received single-dose nevirapine (NVP) to prevent mother-to-child HIV-1 transmission. METHODS: Plasma for testing was collected 6 to 8 weeks postpartum from 301 women (144 subtype A, 63 subtype C, and 94 subtype D). RESULTS: The portion of women with 0.5% or more K103N-containing variants was lowest for subtype A (60/144, 41.7%) and highest for subtype C (44/63, 69.8%; P < 0.0001). K103N was rarely detected in pre-NVP samples. In a multivariate model, K103N detection was associated with HIV-1 subtype (C > A), after adjusting for log10 delivery viral load, the number of days between NVP dosing and sample collection, age, and parity. Among women with K103N detected: (1) the median %K103N was lower for subtype A (2.2%) than C (11.7%, P = 0.0001) or D (5.5%, P = 0.04), and (2) in a multivariate linear model, higher log10 (%K103N) was associated with HIV subtype (C > A, P = 0.0001; D > A, P = 0.01; and C vs D, no difference), but not other factors. CONCLUSIONS: After administration of single-dose NVP, K103N was detected more frequently and at higher levels in women with subtypes C and D than A. Further studies are needed to evaluate the clinical significance of NVP-resistant variants in this setting.

Sensitive drug-resistance assays reveal long-term persistence of HIV-1 variants with the K103N nevirapine (NVP) resistance mutation in some women and infants after the administration of single-dose NVP: HIVNET 012.

BACKGROUND: The HIV Network for Prevention Trials (HIVNET) 012 trial showed that NVP resistance (NVPR) emerged in some women and children after the administration of single-dose nevirapine (SD-NVP). We tested whether K103N-containing human immunodeficiency virus (HIV)-1 variants persisted in women and infants 1 year or more after the administration of SD-NVP. METHODS: We analyzed samples from 9 women and 5 infants in HIVNET 012 who had NVPR 6-8 weeks after the administration of SD-NVP. Samples were analyzed with the ViroSeq system and with 2 sensitive resistance assays, LigAmp and TyHRT. RESULTS: ViroSeq detected the K103N mutation in 8 of 9 women and in 2 of 5 infants. LigAmp detected the K103N mutation at low levels in 8 of 9 women and in 4 of 5 infants. K103N was not detected by ViroSeq 12-24 months after the administration of SD-NVP but was detected by LigAmp in 3 of 9 women and in 1 of 5 infants. K103N was also detected in those samples by use of the TyHRT assay. CONCLUSIONS: K103N-containing variants persist in some women and infants for 1 year or more after the administration of SD-NVP. Sensitive resistance assays may provide new insight into the impact of antiretroviral drug exposure on HIV-1 evolution.