Preferential Targeting of Conserved Gag Regions after Vaccination with a Heterologous DNA Prime-Modified Vaccinia Virus Ankara Boost HIV-1 Vaccine Regimen.

Prime-boost vaccination strategies against HIV-1 often include multiple variants for a given immunogen for better coverage of the extensive viral diversity. To study the immunologic effects of this approach, we characterized breadth, phenotype, function, and specificity of Gag-specific T cells induced by a DNA-prime modified vaccinia virus Ankara (MVA)-boost vaccination strategy, which uses mismatched Gag immunogens in the TamoVac 01 phase IIa trial. Healthy Tanzanian volunteers received three injections of the DNA-SMI vaccine encoding a subtype B and AB-recombinant Gagp37 and two vaccinations with MVA-CMDR encoding subtype A Gagp55 Gag-specific T-cell responses were studied in 42 vaccinees using fresh peripheral blood mononuclear cells. After the first MVA-CMDR boost, vaccine-induced gamma interferon-positive (IFN-γ+) Gag-specific T-cell responses were dominated by CD4+ T cells (P < 0.001 compared to CD8+ T cells) that coexpressed interleukin-2 (IL-2) (66.4%) and/or tumor necrosis factor alpha (TNF-α) (63.7%). A median of 3 antigenic regions were targeted with a higher-magnitude median response to Gagp24 regions, more conserved between prime and boost, compared to those of regions within Gagp15 (not primed) and Gagp17 (less conserved; P < 0.0001 for both). Four regions within Gagp24 each were targeted by 45% to 74% of vaccinees upon restimulation with DNA-SMI-Gag matched peptides. The response rate to individual antigenic regions correlated with the sequence homology between the MVA- and DNA Gag-encoded immunogens (P = 0.04, r2 = 0.47). In summary, after the first MVA-CMDR boost, the sequence-mismatched DNA-prime MVA-boost vaccine strategy induced a Gag-specific T-cell response that was dominated by polyfunctional CD4+ T cells and that targeted multiple antigenic regions within the conserved Gagp24 protein.IMPORTANCE Genetic diversity is a major challenge for the design of vaccines against variable viruses. While including multiple variants for a given immunogen in prime-boost vaccination strategies is one approach that aims to improve coverage for global virus variants, the immunologic consequences of this strategy have been poorly defined so far. It is unclear whether inclusion of multiple variants in prime-boost vaccination strategies improves recognition of variant viruses by T cells and by which mechanisms this would be achieved, either by improved cross-recognition of multiple variants for a given antigenic region or through preferential targeting of antigenic regions more conserved between prime and boost. Engineering vaccines to induce adaptive immune responses that preferentially target conserved antigenic regions of viral vulnerability might facilitate better immune control after preventive and therapeutic vaccination for HIV and for other variable viruses.

The potential of task-shifting in scaling up services for prevention of mother-to-child transmission of HIV: a time and motion study in Dar es Salaam, Tanzania.

BACKGROUND: In many African countries, prevention of mother-to-child transmission of HIV (PMTCT) services are predominantly delivered by nurses. Although task-shifting is not yet well established, community health workers (CHWs) are often informally used as part of PMTCT delivery. According to the 2008 World Health Organization (WHO) Task-shifting Guidelines, many PMTCT tasks can be shifted from nurses to CHWs. METHODS: The aim of this time and motion study in Dar es Salaam, Tanzania, was to estimate the potential of task-shifting in PMTCT service delivery to reduce nurses' workload and health system costs. The time used by nurses to accomplish PMTCT activities during antenatal care (ANC) and postnatal care (PNC) visits was measured. These data were then used to estimate the costs that could be saved by shifting tasks from nurses to CHWs in the Tanzanian public-sector health system. RESULTS: A total of 1121 PMTCT-related tasks carried out by nurses involving 179 patients at ANC and PNC visits were observed at 26 health facilities. The average time of the first ANC visit was the longest, 54 (95% confidence interval (CI) 42-65) min, followed by the first PNC visit which took 29 (95% CI 26-32) minutes on average. ANC and PNC follow-up visits were substantially shorter, 15 (95% CI 14-17) and 13 (95% CI 11-16) minutes, respectively. During both the first and the follow-up ANC visits, 94% of nurses' time could be shifted to CHWs, while 84% spent on the first PNC visit and 100% of the time spent on the follow-up PNC visit could be task-shifted. Depending on CHW salary estimates, the cost savings due to task-shifting in PMTCT ranged from US$ 1.3 to 2.0 (first ANC visit), US$ 0.4 to 0.6 (ANC follow-up visit), US$ 0.7 to 1.0 (first PNC visit), and US$ 0.4 to 0.5 (PNC follow-up visit). CONCLUSIONS: Nurses working in PMTCT spend large proportions of their time on tasks that could be shifted to CHWs. Such task-shifting could allow nurses to spend more time on specialized PMTCT tasks and can substantially reduce the average cost per PMTCT patient.

Job satisfaction and turnover intentions among health care staff providing services for prevention of mother-to-child transmission of HIV in Dar es Salaam, Tanzania.

BACKGROUND: Option B+ for the prevention of mother-to-child transmission (PMTCT) of HIV (i.e., lifelong antiretroviral treatment for all pregnant and breastfeeding mothers living with HIV) was initiated in Tanzania in 2013. While there is evidence that this policy has benefits for the health of the mother and the child, Option B+ may also increase the workload for health care providers in resource-constrained settings, possibly leading to job dissatisfaction and unwanted workforce turnover. METHODS: From March to April 2014, a questionnaire asking about job satisfaction and turnover intentions was administered to all nurses at 36 public-sector health facilities offering antenatal and PMTCT services in Dar es Salaam, Tanzania. Multivariable logistic regression models were used to identify factors associated with job dissatisfaction and intention to quit one's job. RESULTS: Slightly over half (54%, 114/213) of the providers were dissatisfied with their current job, and 35% (74/213) intended to leave their job. Most of the providers were dissatisfied with low salaries and high workload, but satisfied with workplace harmony and being able to follow their moral values. The odds of reporting to be globally dissatisfied with one's job were high if the provider was dissatisfied with salary (adjusted odds ratio (aOR) 5.6, 95% CI 1.2-26.8), availability of protective gear (aOR 4.0, 95% CI 1.5-10.6), job description (aOR 4.3, 95% CI 1.2-14.7), and working hours (aOR 3.2, 95% CI 1.3-7.6). Perceiving clients to prefer PMTCT Option B+ reduced job dissatisfaction (aOR 0.2, 95% CI 0.1-0.8). The following factors were associated with providers' intention to leave their current job: job stability dissatisfaction (aOR 3.7, 95% CI 1.3-10.5), not being recognized by one's superior (aOR 3.6, 95% CI 1.7-7.6), and poor feedback on the overall unit performance (aOR 2.7, 95% CI 1.3-5.8). CONCLUSION: Job dissatisfaction and turnover intentions are comparatively high among nurses in Dar es Salaam's public-sector maternal care facilities. Providing reasonable salaries and working hours, clearer job descriptions, appropriate safety measures, job stability, and improved supervision and feedback will be key to retaining satisfied PMTCT providers and thus to sustain successful implementation of Option B+ in Tanzania.

Virologic and immunologic failure, drug resistance and mortality during the first 24 months postpartum among HIV-infected women initiated on antiretroviral therapy for life in the Mitra plus Study, Dar es Salaam, Tanzania.

BACKGROUND: In the Mitra plus study of prevention of mother-to-child transmission of HIV-1, which included 501 women in Dar es Salaam, Tanzania, triple antiretroviral therapy (ART) was given from late pregnancy throughout breastfeeding up to 6 months postnatally. Here we report findings in a sub-cohort of women with ≤200 CD4cells/µL at enrolment who were continued on ART for life and followed up during 24 months after delivery to determine virologic and immunologic responses, drug resistance and mortality. METHODS: Blood samples for viral load and CD4 counts testing were collected at enrolment and at 3, 6, 12 and 24 months postpartum. HIV drug resistance testing was performed at 12 months. Data analysis included descriptive statistics and multivariate analysis using Generalized Estimated Equations of 73 women with at least two postpartum assessments. The mortality analysis included 84 women who had delivered. RESULTS: The proportion of women with a viral load≥400 copies/mL was 97% (71/73) at enrolment, 16% (11/67), 22% (15/69), 61% (36/59) and 86% (48/56) at 3, 6, 12 and 24 months postpartum, respectively. The proportion of women with immunologic failure was 12% (8/69), 25% (15/60) and 41% (24/58) at 6, 12 and 24 months, respectively. At 12 months, drug resistance was demonstrated in 34% (20/59), including 12 with dual-class resistance. Self-report on drug adherence was 95% (64/68), 85% (56/66), 74% (39/53) and 65% (30/46) at 3, 6, 12 and 24 months, respectively. The mortality rate was 5.9% (95% CI 2.5-13.7%) at 24 months. The probability of virologic and immunologic failure was significantly higher among women who reported non-perfect adherence to ART at month 24 postpartum. CONCLUSIONS: Following an initial decline of viral load, virologic failure was common at 12 and 24 months postpartum among women initiated on ART for life during pregnancy because of low CD4 cell counts. A high proportion of viremic mothers also had resistance mutations. However, at 24 months follow-up, the mortality rate was still fairly low. Continuous adherence counseling and affordable means of monitoring of the virologic response are crucial for successful implementation of the WHO Option B+ guidelines to start all HIV-infected pregnant women on ART for life.

Long-term retention on antiretroviral treatment after enrolment in prevention of vertical HIV transmission services: a prospective cohort study in Dar es Salaam, Tanzania.

INTRODUCTION: To prevent vertical HIV transmission and ensure healthy mothers and children, pregnant women with HIV must remain on antiretroviral treatment (ART) for life. However, motivation to remain on ART may decline beyond the standard 2-year breastfeeding/postpartum period. We assessed attrition and retention in ART care among women with HIV up to 6 years since enrolment in vertical transmission prevention services in Dar es Salaam, Tanzania. METHODS: A prospective cohort of 22,631 pregnant women with HIV were enrolled in vertical transmission prevention services between January 2015 and December 2017 in routine healthcare settings and followed-up to July 2021. Kaplan-Meier was used to estimate time to ART attrition (died, stopped ART or was lost to follow-up [no show ≥90 days since scheduled appointment]) and the proportion retained in care. Cox proportional hazard models were used to estimate adjusted hazard ratios (aHR) of ART attrition in relation to predictors. RESULTS: Participants were followed-up to 6 years for a median of 3 years (IQR: 0.1-4). The overall ART attrition rate was 13.8 per 100 person-years (95% CI: 13.5-14.1), highest in the first year of enrolment at 27.1 (26.3-27.9), thereafter declined to 9.5 (8.9-10.1) in year 3 and 2.7 (2.1-3.5) in year 6. The proportion of women retained in care were 78%, 69%, 63%, 60%, 57% and 56% at 1, 2, 3, 4, 5 and 6 years, respectively. ART attrition was higher in young women aged <20 years (aHR 1.63, 95% CI: 1.38-1.92) as compared to 30-39 year-olds and women enrolled late in the third versus first trimester (aHR 1.29, 95% CI: 1.16-1.44). In contrast, attrition was lower in older women ≥40 years, women who initiated ART before versus during the index pregnancy and women attending higher-level health facilities. CONCLUSIONS: ART attrition among women with HIV remains highest in the first year of enrolment in vertical transmission prevention services and declines markedly following a transition to chronic HIV care. Targeted interventions to improve ART continuity among women with HIV during and beyond prevention of vertical transmission are vital to ending paediatric HIV and keeping women and children alive and healthy.

Reasons for poor adherence to antiretroviral therapy postnatally in HIV-1 infected women treated for their own health: experiences from the Mitra Plus study in Tanzania.

BACKGROUND: In a study of prevention of mother-to-child transmission of HIV (PMTCT) by triple antiretroviral therapy (ART) in Dar es Salaam, Tanzania (the Mitra Plus study), retrospective viral load testing revealed a high and increasing frequency of detectable viral load during follow-up for two years postnatally in women given continuous ART for their own health suggesting poor adherence. This study explored women's own perceived barriers to adherence to ART post-delivery so as to identify ways to facilitate better drug adherence among women in need of ART for their own health. METHODS: Semi-structured interviews were conducted with 23 of the 48 women who had detectable viral load at 24 months postnatally. Content analysis was used to analyze the data. RESULTS: Most women in the study did not acknowledge poor adherence until confronted with the viral load figures. Then, however, they revealed multiple reasons for failing to adhere. They said that their motivation to take ART decreased once they had protected their children from becoming infected and successfully weaned them. Feeling well for some, and a feeling of hopelessness for others, also decreased motivation to continue ART. The overwhelming demands of everyday life, poverty and lack of empowerment also posed significant barriers to long-term adherence. The need to keep their HIV status a secret and not let anyone see them taking the drugs was another steep barrier. CONCLUSION: Reasons for postnatal failure to adhere by mothers put on ART for life during pregnancy included lack of motivation to continue ART after weaning the child, poverty and stigma. Projects that simultaneously address stigma, poverty and women's lack of empowerment may be necessary for PMTCT and ART to reach their full potential. Our results indicate that the new WHO proposal to start all HIV-infected pregnant women on lifelong ART regardless of CD4 cell count needs to address the challenging realities of women in resource-poor contexts if it is to be successful.

Vertical HIV transmission within 18 months post partum among women on lifelong antiretroviral therapy for HIV in Dar es Salaam, Tanzania: a prospective cohort study.

BACKGROUND: The UNAIDS estimate of vertical HIV transmission in Tanzania is high (11%), despite 84% uptake of antiretroviral therapy (ART) among pregnant women with HIV. We aimed to evaluate vertical transmission and its determinants by 18 months post partum among women on lifelong ART in routine health-care settings in Tanzania. METHODS: We conducted a prospective cohort study in 226 health facitilies across Dar-es-Salaam, Tanzania. Eligible participants were pregnant women of any age with HIV, and later their infants, who enrolled in routine health-care services for the prevention of vertical transmission. We prospectively followed up mother-infant pairs at routine monthly visits until 18 months post partum and extracted data from the care and treatment clinic (CTC2) database, a national electronic database that stores patient-level HIV care and treatment clinic data. The primary outcome was time from birth to HIV diagnosis, defined as a positive infant HIV DNA PCR or antibody test from age 18 months. We used the Kaplan-Meier method to estimate cumulative risk of vertical transmission by 18 months post partum and Cox proportional hazards regression with shared frailties to account for potential clustering in health facilities to evaluate predictors of transmission. FINDINGS: Between Jan 1, 2015, and Dec 31, 2017, 22 930 pregnant women with HIV (median age 30 years, IQR 25-34) enrolled on a care programme. After excluding 9140 (39·9%) women and 539 (2·4%) infants with missing outcome data, 13 251 (59·0%) mother-infant pairs were analysed, of whom 6072 (45·8%) women were already on ART before pregnancy. By 18 months post partum, 159 (1·2%) of 13 251 infants were diagnosed with HIV, equivalent to a risk of vertical transmission of 1·4% (95% CI 1·2-1·6). In the complete case analysis, the rates of vertical transmission were higher among women who enrolled in the third trimester of pregnancy than among those who enrolled in the first trimester (adjusted hazard ratio 3·01, 95% CI 1·59-5·70; p=0·0003), among women with advanced HIV disease than among those with early-stage disease (1·89, 1·22-2·93; p=0·0046), and among women who were on a second-line ART regimen than among those on a first-line regimen (3·58, 1·08-11·82; p=0·037). By contrast, the rate of vertical transmission was lower among women who were already on ART at enrolment than among those starting ART at enrolment (0·39, 0·25-0·60; p<0·0001) as well as among women in high-volume clinics than among those in low-volume clinics (0·46 (0·24-0·90; p<0·0097). INTERPRETATION: Provision of ART for life (WHO's option B+ recommendation) has reduced the risk of vertical transmission to less than 2% among pregnant women with HIV in routine care settings in urban Tanzania. There is still a need to improve timely HIV diagnosis and ART uptake, and to optimise follow-up for the prevention of vertical transmission and the uptake of infant HIV testing. FUNDING: Swedish International Development Cooperation Agency.

Immunization with recombinant HLA classes I and II, HIV-1 gp140, and SIV p27 elicits protection against heterologous SHIV infection in rhesus macaques.

Major histocompatibility complex (MHC) molecules expressed on the surface of human immunodeficiency virus (HIV) are potential targets for neutralizing antibodies. Since MHC molecules are polymorphic, nonself MHC can also be immunogenic. We have used combinations of novel recombinant HLA class I and II and HIV/simian immunodeficiency virus (SIV) antigens, all linked to dextran, to investigate whether they can elicit protective immunity against heterologous simian/human immunodeficiency virus (SHIV) challenge in rhesus macaques. Three groups of animals were immunized with HLA (group 1, n = 8), trimeric YU2 HIV type 1 (HIV-1) gp140 and SIV p27 (HIV/SIV antigens; group 2, n = 8), or HLA plus HIV/SIV antigens (group 3, n = 8), all with Hsp70 and TiterMax Gold adjuvant. Another group (group 4, n = 6) received the same vaccine as group 3 without TiterMax Gold. Two of eight macaques in group 3 were completely protected against intravenous challenge with 18 50% animal infective doses (AID(50)) of SHIV-SF162P4/C grown in human cells expressing HLA class I and II lineages represented in the vaccine, while the remaining six macaques showed decreased viral loads compared to those in unimmunized animals. Complement-dependent neutralizing activity in serum and high levels of anti-HLA antibodies were elicited in groups 1 and 3, and both were inversely correlated with the plasma viral load at 2 weeks postchallenge. Antibody-mediated protection was strongly supported by the fact that transfer of pooled serum from the two challenged but uninfected animals protected two naïve animals against repeated low-dose challenge with the same SHIV stock. This study demonstrates that immunization with recombinant HLA in combination with HIV-1 antigens might be developed into an alternative strategy for a future AIDS vaccine.

The Prevalence, Incidence, and Risk Factors for HIV Among Female Sex Workers-A Cohort Being Prepared for a Phase IIb HIV Vaccine Trial in Dar es Salaam, Tanzania.

BACKGROUND: A cohort of female sex workers (FSWs) was established to determine HIV prevalence and incidence, and associated factors in preparation for a phase IIb HIV vaccine and pre-exposure prophylaxis trial (PrEPVacc). SETTING: A cohort of FSWs in Dar es Salaam, Tanzania. METHODS: FSWs aged 18-45 years were recruited using a respondent-driven sampling method. Social demographic data, HIV risk behavioral assessments, and blood samples for testing of HIV, syphilis, hepatitis B (HBV), and hepatitis C (HCV) infections were collected at baseline and then at 3, 6, 9, and 12 months. Poisson regressions were used to estimate the prevalence ratios for factors associated with HIV prevalence and to estimate the 12-month HIV incidence rate. RESULTS: Between October and December 2018, a total of 773 FSWs were screened for eligibility and 700 were enrolled. The baseline prevalence of HIV, syphilis, HBV, and HCV was 7.6%, 1.2%, 1.7%, and 1.0%, respectively. HIV prevalence was associated with older age, using illicit drugs, and being infected with syphilis, HBV, or HCV. Attendance at 12 months was 80% (562/700). Twenty-one FSWs seroconverted during follow-up, giving a 12-month HIV incidence rate of 3.45 per 100 person-years at risk (95% CI; 2.25-5.28/100 person-years at risk). The HIV incidence rate was higher among FSWs aged 18-24 years, FSWs who used drugs, and those diagnosed with syphilis, HBV, or HCV. CONCLUSION: The high HIV incidence rate and retention rate among FSWs enrolled into the cohort demonstrate that this population is suitable for participation in HIV prevention trials.

Effect of peer-mother interactive programme on prevention of mother-to-child HIV transmission outcomes among pregnant women on anti-retroviral treatment in routine healthcare in Dar es Salaam, Tanzania.

Peer support services are increasingly being integrated in programmes for the prevention of mother-to-child HIV transmission (PMTCT). We aimed to evaluate the effect of a peer-mother interactive programme on PMTCT outcomes among pregnant women on anti-retroviral treatment (ART) in routine healthcare in Dar es Salaam, Tanzania. Twenty-three health facilities were cluster-randomized to a peer-mother intervention and 24 to a control arm. We trained 92 ART experienced women with HIV to offer peer education, adherence and psychosocial support to women enrolling in PMTCT care at the intervention facilities. All pregnant women who enrolled in PMTCT care at the 47 facilities from 1st January 2018 to 31st December 2019 were identified and followed up to 31st July 2021. The primary outcome was time to ART attrition (no show >90 days since the scheduled appointment, excluding transfers) and any difference in one-year retention in PMTCT and ART care between intervention and control facilities. Secondary outcomes were maternal viral suppression (<400 viral copies/mL) and mother-to-child HIV transmission (MTCT) by ≥12 months post-partum. Analyses were done using Kaplan Meier and Cox regression (ART retention/attrition), generalized estimating equations (viral suppression) and random effects logistic regression (MTCT); reporting rates, proportions and 95% confidence intervals (CI). There were 1957 women in the peer-mother and 1384 in the control facilities who enrolled in routine PMTCT care during 2018-2019 and were followed for a median [interquartile range (IQR)] of 23 [10, 31] months. Women in both groups had similar median age of 30 [IQR 25, 35] years, but differed slightly with regard to proportions in the third pregnancy trimester (14% versus 19%); advanced HIV (22% versus 27%); and ART naïve (55% versus 47%). Peer-mother facilities had a significantly lower attrition rate per 1000 person months (95%CI) of 14 (13, 16) versus 18 (16, 19) and significantly higher one-year ART retention (95%CI) of 78% (76, 80) versus 74% (71, 76) in un-adjusted analyses, however in adjusted analyses the effect size was not statistically significant [adjusted hazard ratio of attrition (95%CI) = 0.85 (0.67, 1.08)]. Viral suppression (95%CI) was similar in both groups [92% (91, 93) versus 91% (90, 92)], but significantly higher among ART naïve women in peer-mother [91% (89, 92)] versus control [88% (86, 90)] facilities. MTCT (95%CI) was similar in both groups [2.2% (1.4, 3.4) versus 1.5% (0.7, 2.8)]. In conclusion, we learned that integration of peer-mother services in routine PMTCT care improved ART retention among all women and viral suppression among ART naïve women but had no significant influence on MTCT.

Health care costs associated with clinic visits for prevention of mother-to-child transmission of HIV in Dar es Salaam, Tanzania.

ABSTRACT: Early and appropriate antenatal care (ANC) is key for the effectiveness of prevention of mother-to-child transmission (PMTCT) of human immunodeficiency virus (HIV). We evaluated the importance of ANC visits and related service costs for women receiving option B+ to prevent mother-to-child transmission (MTCT) of HIV in Tanzania.A cost analysis from a health care sector perspective was conducted using routine data of 2224 pregnant women newly diagnosed with HIV who gave birth between August 2014 and May 2016 in Dar es Salaam, Tanzania. We evaluated risk of infant HIV infection at 12 weeks postnatally in relation to ANC visits (<4 vs ≥4 visits). Costs for service utilisation were estimated through empirical observations and the World Health Organisation Global Price Reporting Mechanism.Mean gestational age at first ANC visit was 22 (±7) weeks. The average number of ANC/prevention of MTCT visits among the 2224 pregnant women in our sample was 3.6 (95% confidence interval [CI] 3.6-3.7), and 57.3% made ≥4 visits. At 12 weeks postnatally, 2.7% (95% CI 2.2-3.6) of HIV exposed infants had been infected. The risk of MTCT decreased with the number of ANC visits: 4.8% (95% CI 3.6-6.4) if the mother had <4 visits, and 1.0% (95% CI 0.5-1.7) at ≥4. The adjusted MTCT rates decreased by 51% (odds ratio 0.49, 95% CI 0.31-0.77) for each additional ANC visit made. The potential cost-saving was 2.2 US$ per woman at ≥4 visits (84.8 US$) compared to <4 visits (87.0 US$), mainly due to less defaulter tracing.Most pregnant women living with HIV in Dar es Salaam initiated ANC late and >40% failed to adhere to the recommended minimum of 4 visits. Improved ANC attendance would likely lead to fewer HIV-infected infants and reduce both short and long-term health care costs due to less spending on defaulter tracing and future treatment costs for the children.

Long-term virological outcomes in women who started option B+ care during pregnancy for prevention of mother-to-child transmission of HIV in Dar es Salaam, Tanzania: a cohort study.

BACKGROUND: Option B+ marked a milestone in prevention of mother-to-child transmission (PMTCT) of HIV by recommending lifelong antiretroviral therapy (ART) for all pregnant women with HIV. Nevertheless, concerns remain regarding long-term outcomes in settings with a high HIV burden. We analysed long-term virological outcomes in women enrolled on option B+ in Tanzania. METHODS: In this prospective cohort study, we extracted data for pregnant women with HIV starting PMTCT care between Oct 1, 2014, and Sept 30, 2016, in routine health-care settings in Dar es Salaam, Tanzania, from national HIV and district health information system databases. We then excluded women who exited study sites before 6 months of ART follow-up and women who did not have a viral load test. Women were followed up until March 8, 2019. We used Poisson generalised estimating equations to examine trends in HIV viral suppression (<400 copies per mL) and virological failure (≥400 copies per mL), reporting relative risks (RRs) and 95% CIs adjusted for maternal age, gestational age, and several clinical characteristics. FINDINGS: We identified 15 586 pregnant women with HIV, of whom 10 161 were eligible for follow-up. Women were followed up for a median of 37 months (IQR 31-45) and a maximum of 53 months. The median age at PMTCT initiation was 31 years (IQR 27-35). At PMTCT enrolment, 1245 (17·0%) of 7318 women with available data were in their third trimester, 4901 (48·2%) of 10 161 women started ART at least 1 month before PMTCT enrolment, and 3380 (33·4%) of 10 131 women with available data had advanced HIV. Overall, a viral suppression rate of 88·2% (95% CI 87·8-88·7) was observed over the entire follow-up period, ranging from 85·1% (84·3-85·9) in viral load tests done at 0-11 months to 90·6% (89·7-91·4) at 36 months or longer since PMTCT enrolment. In a complete-case analysis (ie, including patients with <30% missing data; n=7306), the risk of virological failure among women who remained in HIV care decreased over time (adjusted RR 0·87 [95% CI 0·80-0·95] at 12-23 months since PMTCT enrolment; 0·65 [0·59-0·72] at 24-35 months; and 0·63 [0·55-0·71] at ≥36 months vs at 0-11 months). Younger women (aged <20 years: 1·76 [1·40-2·23] vs aged 30-39 years) and those starting PMTCT late in pregnancy (third trimester: 1·28 [1·10-1·50] vs first trimester) or with advanced HIV (1·33 [1·16-1·51] vs without advanced HIV) had increased risk of virological failure. Women who attended an antenatal care facility where more than 50% of attendees received couples HIV testing had a decreased risk of virological failure (adjusted RR 0·81 [0·65-0·99] vs <50% having couples testing). INTERPRETATION: High rates of viral suppression among women starting option B+ who remain in HIV care are sustainable, and might increase, at least up to 53 months. This rate might be further improved by addressing challenges of adolescent mothers, late presenters, and couples HIV testing at antenatal care. FUNDING: Swedish International Development Agency.

Frequent and Durable Anti-HIV Envelope VIV2 IgG Responses Induced by HIV-1 DNA Priming and HIV-MVA Boosting in Healthy Tanzanian Volunteers.

We evaluated antibody responses to the human immunodeficiency virus (HIV) envelope variable regions 1 and 2 (V1V2) in 29 vaccinees who had received three HIV-1 DNA immunizations and two HIV-modified vaccinia virus Ankara (MVA) boosts in the phase I/II HIVIS03 vaccine trial. Twenty vaccinees received a third HIV-MVA boost after three years in the HIVIS06 trial. IgG and IgG antibody subclasses to gp70V1V2 proteins of HIV-1 A244, CN54, Consensus C, and Case A2 were analysed using an enzyme-linked immunosorbent assay (ELISA). Cyclic V2 peptides of A244, Consensus C, and MN were used in a surface plasmon resonance (SPR) assay. Four weeks after the second HIV-MVA, anti-V1V2 IgG antibodies to A244 were detected in 97% of HIVIS03 vaccinees, in 75% three years later, and in 95% after the third HIV-MVA. Anti-CN54 V1V2 IgG was detectable in 48% four weeks after the second HIV-MVA. The SPR data supported the findings. The IgG response was predominantly IgG1. Four weeks after the second HIV-MVA, 85% of vaccinees had IgG1 antibodies to V1V2 A244, which persisted in 25% for three-years. IgG3 and IgG4 antibodies to V1V2 A244 were rare. In conclusion, the HIV-DNA/MVA vaccine regimen induced durable V1V2 IgG antibody responses in a high proportion of vaccinees.

Induction of Identical IgG HIV-1 Envelope Epitope Recognition Patterns After Initial HIVIS-DNA/MVA-CMDR Immunization and a Late MVA-CMDR Boost.

In the RV144 trial, to date the only HIV-1 vaccine efficacy trial demonstrating a modestly reduced risk of HIV-1 acquisition, antibody responses toward the HIV Envelope protein (Env) variable (V) 2 and V3 regions were shown to be correlated with a reduced risk of infection. These potentially protective antibody responses, in parallel with the vaccine efficacy, however, waned quickly. Dissecting vaccine-induced IgG recognition of antigenic regions and their variants within the HIV-1 Env from different vaccine trials will aid in designing future HIV-1 immunogens and vaccination schedules. We, therefore, analyzed the IgG response toward linear HIV-1 Env epitopes elicited by a multi-clade, multigene HIVIS-DNA priming, and heterologous recombinant modified vaccinia virus Ankara (MVA-CMDR) boosting regimen (HIVIS03) and assessed whether a late MVA-CMDR boost 3 years after completion of the initial vaccination schedule (HIVIS06) restored antibody responses toward these epitopes. Here we report that vaccination schedule in the HIVIS03 trial elicited IgG responses against linear epitopes within the V2 and V3 tip as well as against the gp41 immunodominant region in a high proportion of vaccinees. Antibodies against the V2 and gp41 Env regions were restricted to variants with close homology to the MVA-CMDR immunogen sequence, while V3 responses were more cross-reactive. Boosting with a late third MVA-CMDR after 3 years effectively restored waned IgG responses to linear Env epitopes and induced targeting of identical antigenic regions and variants comparable to the previous combined HIVIS-DNA/MVA-CMDR regimen. Our findings support the notion that anti-HIV-1 Env responses, associated with a reduced risk of infection in RV144, could be maintained by regular boosting with a single dose of MVA-CMDR.

Frequent Anti-V1V2 Responses Induced by HIV-DNA Followed by HIV-MVA with or without CN54rgp140/GLA-AF in Healthy African Volunteers.

Antibody responses that correlated with reduced risk of HIV acquisition in the RV144 efficacy trial were assessed in healthy African volunteers who had been primed three times with HIV-DNA (subtype A, B, C) and then randomized into two groups; group 1 was boosted twice with HIV-MVA (CRF01_AE) and group 2 with the same HIV-MVA coadministered with subtype C envelope (Env) protein (CN54rgp140/GLA-AF). The fine specificity of plasma Env-specific antibody responses was mapped after the final vaccination using linear peptide microarray technology. Binding IgG antibodies to the V1V2 loop in CRF01_AE and subtype C Env and Env-specific IgA antibodies were determined using enzyme-linked immunosorbent assay. Functional antibody-dependent cellular cytotoxicity (ADCC)-mediating antibody responses were measured using luciferase assay. Mapping of linear epitopes within HIV-1 Env demonstrated strong targeting of the V1V2, V3, and the immunodominant region in gp41 in both groups, with additional recognition of two epitopes located in the C2 and C4 regions in group 2. A high frequency of V1V2-specific binding IgG antibody responses was detected to CRF01_AE (77%) and subtype C antigens (65%). In conclusion, coadministration of CN54rgp140/GLA-AF with HIV-MVA did not increase the frequency, breadth, or magnitude of anti-V1V2 responses or ADCC-mediating antibodies induced by boosting with HIV-MVA alone.

Comparison of the performance of rapid HIV tests using samples collected for surveillance in Mozambique.

Mozambique had low HIV prevalence until the mid-1990s, but recent data indicate increasing rates. There is little information on HIV-2. Therefore, HIV seroprevalence was assessed among pregnant women and field-ready HIV diagnostic strategies were evaluated. A total of 6,930 samples collected by three health centers from 2002 to 2005 were tested on site by nurses with two simple/rapid tests, Determine HIV-1/2 (Abbott Laboratories; screening) and Uni-Gold HIV (Trinity Biotech; confirmation), which is the national HIV testing strategy. The prevalence of HIV was 14.0% (2002), 17.8% (2003), 16.5% (2004), and 20.2% (2005). A subset of 888 samples collected 2003 was sent to the Central Microbiology Laboratory, Maputo for evaluation of tests and testing strategies. The assays included for comparison were Capillus HIV-1/HIV-2 (Trinity Biotech), DoubleCheckGold HIV-1&2 (Orgenics) and Enzygnost Anti-HIV-1/2 Plus (Behringwerke, reference ELISA). Confirmation of reactive samples was done by Uni-Gold HIV and ImmunoComb II HIV-1&2 BiSpot (for HIV type differentiation). The Capillus HIV-1/ HIV-2 + ImmunoComb II HIV-1&2 BiSpot combination was the gold standard. The sensitivity of the rapid/simple screening assays (Determine HIV-1/2, DoubleCheckGold HIV-1&2) was 100% (N = 160) and their (initial) specificities were 99.6% and 99.7%, respectively. Repeated testing and combinations of assays increased the specificity. Four suspected cases of recent seroconversion were found. Together with the increasing prevalence rates, this may indicate that Mozambique is a high-incidence area, although further studies are needed to confirm this. Testing strategies for on-site screening and confirmation based on the combination of Determine HIV-1/2, Uni-Gold HIV and DoubleCheckGold HIV-1&2 are well suited for local field use.

Intradermal HIV-1 DNA Immunization Using Needle-Free Zetajet Injection Followed by HIV-Modified Vaccinia Virus Ankara Vaccination Is Safe and Immunogenic in Mozambican Young Adults: A Phase I Randomized Controlled Trial.

We assessed the safety and immunogenicity of HIV-DNA priming using Zetajet™, a needle-free device intradermally followed by intramuscular HIV-MVA boosts, in 24 healthy Mozambicans. Volunteers were randomized to receive three immunizations of 600 µg (n = 10; 2 × 0.1 ml) or 1,200 µg (n = 10; 2 × 0.2 ml) of HIV-DNA (3 mg/ml), followed by two boosts of 108 pfu HIV-MVA. Four subjects received placebo saline injections. Vaccines and injections were safe and well tolerated with no difference between the two priming groups. After three HIV-DNA immunizations, IFN-γ ELISpot responses to Gag were detected in 9/17 (53%) vaccinees, while none responded to Envelope (Env). After the first HIV-MVA, the overall response rate to Gag and/or Env increased to 14/15 (93%); 14/15 (93%) to Gag and 13/15 (87%) to Env. There were no significant differences between the immunization groups in frequency of response to Gag and Env or magnitude of Gag responses. Env responses were significantly higher in the higher dose group (median 420 vs. 157.5 SFC/million peripheral blood mononuclear cell, p = .014). HIV-specific antibodies to subtype C gp140 and subtype B gp160 were elicited in all vaccinees after the second HIV-MVA, without differences in titers between the groups. Neutralizing antibody responses were not detected. Two (13%) of 16 vaccinees, one in each of the priming groups, exhibited antibodies mediating antibody-dependent cellular cytotoxicity to CRF01_AE. In conclusion, HIV-DNA vaccine delivered intradermally in volumes of 0.1-0.2 ml using Zetajet was safe and well tolerated. Priming with the 1,200 µg dose of HIV-DNA generated higher magnitudes of ELISpot responses to Env.

Engaging community leaders to improve male partner participation in the prevention of mother-to-child transmission of HIV in Dar es Salaam, Tanzania.

BACKGROUND: Male partner participation improves uptake, retention and outcomes of prevention of mother-to-child transmission of HIV (PMTCT) services. However, in patriarchal settings few men accompany their partners to antenatal care (ANC) and PMTCT services. We explored whether community leaders can improve male partner participation in ANC and PMTCT. METHODS: We integrated initiatives to increase male partner participation in routine ANC care in six health facilities (attending about 4,500 new pregnant women per quarter) in Dar es Salaam, Tanzania in 2015/16. These initiatives were adapted from a best performing health facility, on male partner participation in ANC and PMTCT, referred to as the "best practice site". At the six purposively selected intervention sites, we sensitized and garnered commitment from healthcare providers to provide couple friendly services. We then worked with the providers to sensitize and engage community leaders to integrate and promote male partner participation initiatives in their routine community activities. We assessed change in male partner participation in ANC and PMTCT using the proportion of women testing for HIV together with their partners (i.e. couple HIV testing) by quarter. We used 203 ANC facilities (attending about 31,000 new pregnant women per quarter) in the same area as control sites. RESULTS: After one year, couple HIV testing in the six intervention sites had tripled from 11.9% at baseline to 36.0% (p<0.001) while there was very little change (from 17.7% to 18.3%) in the 203 control sites (p = 0.07). Statistically significant improvements in couple testing were observed in four of the six intervention sites (6.7% to 19.1%; 9.3% to 74.6%; 46.2% to 95.2%; and 4.7% to 15.1% respectively. p<0.001 for all sites). Two of these four sites, located in the same administrative district as the best practice site, achieved remarkably high couple HIV testing (95.2% and 74.6%). This may be attributable to the greater engagement and active participation of the community leaders in these two sites compared to the other four. CONCLUSION: Effective engagement and functional partnerships between healthcare providers and community leaders can contribute to improve male partner participation in ANC and PMTCT services. PMTCT programs should capitalize on community leaders, in addressing low male partner participation in ANC and PMTCT, in order to improve effective uptake, retention and outcomes of HIV prevention and treatment services among pregnant and breastfeeding women, their partners, infants and families.

Optimizing the immunogenicity of HIV prime-boost DNA-MVA-rgp140/GLA vaccines in a phase II randomized factorial trial design.

BACKGROUND: We evaluated the safety and immunogenicity of (i) an intradermal HIV-DNA regimen given with/without intradermal electroporation (EP) as prime and (ii) the impact of boosting with modified vaccinia virus Ankara (HIV-MVA) administered with or without subtype C CN54rgp140 envelope protein adjuvanted with Glucopyranosyl Lipid A (GLA-AF) in volunteers from Tanzania and Mozambique. METHODS: Healthy HIV-uninfected adults (N = 191) were randomized twice; first to one of three HIV-DNA intradermal priming regimens by needle-free ZetaJet device at weeks 0, 4 and 12 (Group I: 2x0.1mL [3mg/mL], Group II: 2x0.1mL [3mg/mL] plus EP, Group III: 1x0.1mL [6mg/mL] plus EP). Second the same volunteers received 108 pfu HIV-MVA twice, alone or combined with CN54rgp140/GLA-AF, intramuscularly by syringe, 16 weeks apart. Additionally, 20 volunteers received saline placebo. RESULTS: Vaccinations and electroporation did not raise safety concerns. After the last vaccination, the overall IFN-γ ELISpot response rate to either Gag or Env was 97%. Intradermal electroporation significantly increased ELISpot response rates to HIV-DNA-specific Gag (66% group I vs. 86% group II, p = 0.026), but not to the HIV-MVA vaccine-specific Gag or Env peptide pools nor the magnitude of responses. Co-administration of rgp140/GLA-AF with HIV-MVA did not impact the frequency of binding antibody responses against subtype B gp160, C gp140 or E gp120 antigens (95%, 99%, 79%, respectively), but significantly enhanced the magnitude against subtype B gp160 (2700 versus 300, p<0.001) and subtype C gp140 (24300 versus 2700, p<0.001) Env protein. At relatively low titers, neutralizing antibody responses using the TZM-bl assay were more frequent in vaccinees given adjuvanted protein boost. CONCLUSION: Intradermal electroporation increased DNA-induced Gag response rates but did not show an impact on Env-specific responses nor on the magnitude of responses. Co-administration of HIV-MVA with rgp140/GLA-AF significantly enhanced antibody responses.

Three-Year Durability of Immune Responses Induced by HIV-DNA and HIV-Modified Vaccinia Virus Ankara and Effect of a Late HIV-Modified Vaccinia Virus Ankara Boost in Tanzanian Volunteers.

We explored the duration of immune responses and the effect of a late third HIV-modified vaccinia virus Ankara (MVA) boost in HIV-DNA primed and HIV-MVA boosted Tanzanian volunteers. Twenty volunteers who had previously received three HIV-DNA and two HIV-MVA immunizations were given a third HIV-MVA immunization 3 years after the second HIV-MVA boost. At the time of the third HIV-MVA, 90% of the vaccinees had antibodies to HIV-1 subtype C gp140 (median titer 200) and 85% to subtype B gp160 (median titer 100). The majority of vaccinees had detectable antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies, 70% against CRF01_AE virus-infected cells (median titer 239) and 84% against CRF01_AE gp120-coated cells (median titer 499). A high proportion (74%) of vaccinees had IFN-γ ELISpot responses, 63% to Gag and 42% to Env, 3 years after the second HIV-MVA boost. After the third HIV-MVA, there was an increase in Env-binding antibodies and ADCC-mediating antibodies relative to the response seen at the time of the third HIV-MVA vaccination, p < .0001 and p < .05, respectively. The frequency of IFN-γ ELISpot responses increased to 95% against Gag or Env and 90% to both Gag and Env, p = .064 and p = .002, respectively. In conclusion, the HIV-DNA prime/HIV-MVA boost regimen elicited potent antibody and cellular immune responses with remarkable durability, and a third HIV-MVA immunization significantly boosted both antibody and cellular immune responses relative to the levels detected at the time of the third HIV-MVA, but not to higher levels than after the second HIV-MVA.