Humoral Immune Responses following COVID-19 Vaccinations among Adults in Tanzania

COVID-19 vaccination remains to be the most important intervention in the fight against the pandemic. The immunity among the vaccinated population and its durability can significantly vary due to various factors. This study investigated the humoral immune responses among individuals who received any of the COVID-19 vaccines approved for use in Tanzania. A total of 1048 randomly selected adults who received COVID-19 vaccines at different time points were enrolled and humoral immune responses (IR) were tested at baseline and three months later (960, 91.6%). The level of SARS-CoV-2 anti-spike/receptor binding domain (RBD) IgG, anti-nucleocapsid IgG, and IgM antibodies were determined using a commercially available chemiluminescent microparticle immunoassay. Descriptive data analysis was performed using STATA version 18 and R. At baseline, serum IgG against anti-spike/RBD was detected in 1010/1048 (96.4%) participants (95%CI: 94.9-97.5) and 98.3% (95%CI: 97.3-99) three months later. The IgG against the SARS-CoV-2 nucleocapsid proteins were detected in 40.8% and 45.3% of participants at baseline and follow-up, respectively. The proportion of seroconverters following vaccination and mean titers of anti-spike/RBD antibodies were significantly more among those who had past SARS-CoV-2 infection than in those with no evidence of past infection, (p < 0.001). Only 0.5% of those who had detectable anti-spike/RBD antibodies at baseline were negative after three months of follow-up and 1.5% had breakthrough infections. The majority of participants (99.5%) had detectable anti-spike/RBD antibodies beyond 6 months post-vaccination. The proportion of Tanzanians who mounted humoral IR following COVID-19 vaccination was very high. Seroconversions, as well as the mean titers and durability of humoral IR, were significantly enhanced by exposure to natural SARS-CoV-2 infection. In view of the limited availability of COVID-19 vaccines as well as challenges to completing subsequent doses, booster doses could only be suggested to high-risk groups.

Impact of differentiated service delivery models on retention in HIV care and viral suppression among people living with HIV in sub-Saharan Africa: A systematic review and meta-analysis of randomised controlled trials

Differentiated service delivery (DSD) models, such as adherence clubs (ACs), are client-centred approaches where clinically stable people living with HIV (PLHIV) meet to receive various services, including psychosocial support, brief symptoms screening, and refills of antiretroviral medications, among others. We conducted a review to assess the impact of DSD models, including ACs, on sustaining retention in care (RC) and achieving viral suppression (VS) among PLHIV in sub-Saharan Africa. The review protocol was registered in PROSPERO (CRD42023418988). We searched the literature from PubMed, Scopus, Web of Science, Embase and Google Scholar from their inception through May 2023. Eligible randomised controlled trials of adherence clubs were reviewed to assess impact on retention and viral suppression. Random effect models were used to estimate the risk ratios (RR) and 95% confidence intervals (CI). The literature search yielded a total of 1596 records of which 16 randomised clinical trials were determined to be eligible. The trials were conducted in diverse populations among adults and children with a total of 13,886 participants. The RR between any DSD models and standard of care (SoC) was 1.09 (95% CI: 1.08-1.11, I2 : 0%, p: <0.96) and 1.01 (95% CI: 1.00-1.02, I2 : 0%, p: <0.85) for RC and VS, respectively. The RR between ACs and SoC was 1.01 (95% CI: 0.96-1.07, I2 : 84%, p: <0.01) and 1.02 (95% CI: 0.98-1.07, I2 : 77%, p: <0.01) for RC and VS, respectively. DSD models, including ACs, show comparable effectiveness to SoC in maintaining care and achieving viral suppression for stable PLHIV. To maximise adoption, an implementation science approach is crucial for designing effective strategies and overcoming challenges.

The role of community pharmacies in early detection of suspected COVID-19 cases in 2020: lessons from Dar es Salaam, Tanzania

Tanzania reported its first COVID-19 case on 16 March 2020. We conducted event-based surveillance of COVID-19 suspect cases among pharmacy clients presenting with respiratory symptoms and influenza-like illness to increase early and rapid detection of COVID-19 cases and mitigate transmission. We conveniently sampled 103 pharmacies from Dar es Salaam, the epicentre for the COVID-19 pandemic in Tanzania at the time. Between 23 April 2020 and 18 May 2020, 67% of the pharmacies (69/103) reported an observed increase in the number of clients presenting with respiratory symptoms and influenza-like illness compared with the 1 month before the COVID-19 outbreak. In the 1-month surveillance period, the participating pharmacies recorded 75 alerts of COVID-19 suspect cases and referred all suspected COVID-19 cases to rapid response teams for additional symptomatic screening and SARS-CoV-2 testing. A key implementation challenge was that some clients identified as COVID-19 suspected cases were hesitant to provide follow-up information for linkage to rapid response teams. Addressing concerns among drug dispensers in the participating pharmacies and informing them of the benefits of the surveillance activity were important implementation components. Our approach demonstrates the overall feasibility of rapidly implementing an event-based surveillance system for an emerging health threat through an existing network of pharmacies within the community. The approach and tools used in this surveillance activity could be adapted in similar settings to detect and generate alerts of disease outbreaks in the community that other surveillance systems may otherwise miss.

Personal experiences following acquiring HIV infection while volunteering in Phase I/II HIV vaccine trials: A qualitative study from Tanzania

BACKGROUND

Participation in HIV vaccine trials is an essential step towards development of an effective preventive vaccine. A Phase I/II HIV vaccine trial enrolls volunteers at low risk of acquiring HIV infection, however a few may still become infected. Understanding the experiences of volunteers who acquired HIV infection while participating in such trials is essential for future research. Here, we describe experiences of HIV infected volunteers in Phase I/II HIV vaccine trials conducted in urban Tanzania.

MATERIALS AND METHODS

We used a case study design. In-depth interviews were conducted with four participants who became HIV infected during long follow-up visits after completion of vaccination schedules in a Phase I/II trial. Between 3 and 8 years after HIV positive diagnosis, each participant was interviewed at three time points within a two-year interval so as to allow for accumulation of experiences and cross-checking the emerging constructs. Data was analyzed using a qualitative data analysis framework.

RESULTS

Analysis revealed that participation in HIV vaccine trials involves balancing controversies and the spirit of informed decision. The participants declared that they did not acquire HIV from the experimental vaccine. Disclosure of HIV status within the family was gender specific. Men were hesitant to disclose their HIV status to their sexual partners fearing for the consequences. Women's attempt to disclose their HIV status yielded negative reactions from the sexual partners. The acquired knowledge from the HIV vaccine research enabled the participants to cope with the uncertainties and their health status.

CONCLUSIONS

The knowledge acquired during the Phase I/II HIV vaccine trial appears to be an essential resource to cope with uncertainties post research. The HIV vaccine trial implementers need to understand the challenges the volunteers may confront after the trial while coping with their health status. Longitudinal studies are essential to trace the effects of uncertainties to the individual participants.

Compliance to infection prevention and control interventions for slowing down COVID-19 in early phase of disease transmission in Dar es Salaam, Tanzania

Introduction

on 16^th March 2020, Tanzania announced its first COVID-19 case. The country had already developed a 72-hour response plan and had enacted three compulsory infection prevention and control interventions. Here, we describe public compliance to Infection Prevention and Control (IPC) public health measures in Dar es Salaam during the early COVID-19 response and testing of the feasibility of an observational method.

Methods

a cross sectional study was conducted between April and May 2020 in Dar es Salaam City. At that time, Dar es Salaam was the epi centre of the epidemic. Respondents were randomly selected from defined population strata (high, medium and low). Data were collected using a structured questionnaire and through observations.

Results

a total of 390 subjects were interviewed, response rate was 388 (99.5%). Mean age of the respondents was 34.8 years and 168 (43.1%) had primary level education. Out of the 388 respondents, 384 (98.9%) reported to have heard about COVID-19 public health and social measures, 90.0% had heard from the television and 84.6% from the radio. Covering coughs and sneezes using a handkerchief was the most common behaviour observed among 320 (82.5%) respondents; followed by hand washing hygiene practice, 312 (80.4%) and wearing face masks, 240 (61.9%). Approximately 215 (55.4%) adhered to physical distancing guidance. Age and gender were associated with compliance to IPC measures (both, p<0.05).

Conclusion

compliance to public health measures during the early phase of COVID-19 pandemic in this urban setting was encouraging. As the pandemic continues, it is critical to ensure compliance is sustained and capitalize on risk communication via television and radio.

Evaluation of a New Field Epidemiology Training Program Intermediate Course to Strengthen Public Health Workforce Capacity in Tanzania

OBJECTIVES

Sub-Saharan Africa faces a shortage of skilled epidemiologists to prevent, detect, and respond to health threats. Tanzania has implemented one of the first Centers for Disease Control and Prevention Field Epidemiology Training Program (FETP) Intermediate courses in Africa. This course aims to strengthen health workforce capacity in surveillance system assessment, outbreak investigation, and evaluation, prioritizing HIV control. We conducted an outcome evaluation of this new course.

METHODS

We used a pre/post evaluation design using data from 4 cohorts of trainees who took the FETP Intermediate course from 2017 to 2020. We conducted knowledge assessments before and after each cohort and combined those results. Outcomes included knowledge and self-rated competency and trends in integrated disease surveillance and response (IDSR) data. We collected data through tests, field assignments, exit interviews, and data audits. We compared the mean change in pre-/posttest scores using linear regression and 95% CIs. We used content analysis to summarize exit interviews.

RESULTS

Fifty-three FETP trainees from 10 regions enrolled in the FETP Intermediate course, and 52 (99.0%) completed the course. We found substantial increases in mean knowledge (44.0 to 68.0 points) and self-rated competency (4.14 to 4.43) scores before and after the course. Trainees evaluated 52 surveillance systems and 52 district HIV care programs, and 39 (75.0%) trainees participated in outbreak investigations. From before to after cohort 1, timeliness and completeness of IDSR reports increased from 4.2% to 52.1% and from 27.4% to 76.5%, respectively. Course strengths were quality of instruction, individualized mentoring, and practical skills gained. Challenges were mentor availability, limited time for data analysis practice, and balancing work and field assignments.

CONCLUSIONS

The Tanzania FETP Intermediate course substantially improved trainee knowledge and helped to improve local data quality and reporting. This course is a promising model to strengthen subnational capacity to prevent, detect, and respond to public health threats in Africa.

"I did not plan to have a baby. This is the outcome of our work": a qualitative study exploring unintended pregnancy among female sex workers

BACKGROUND

High number of unintended pregnancies-often leading to induced abortions-are reported among female sex workers (FSWs), highlighting a major unmet need for contraception. To better understand barriers to contraceptive use, we explored FSW's pregnancy perceptions and experiences of unintended pregnancy. We hypothesized that sex work exacerbates barriers to contraceptive use and that FSW's pregnancy perceptions and experiences of unintended pregnancy influence future commitment to contraceptive use.

METHODS

We conducted in-depth interviews with 11 FSWs (January-June 2019) in Dar es Salaam, Tanzania. We purposively sampled FSWs with a positive pregnancy test from those participating in a HIV vaccine preparedness cohort. We used open ended questions to explore how FSWs make decisions when facing barriers to contraceptive use, dealing with unintended pregnancy and adhering to contraceptive use after experiencing unintended pregnancy. All interviews were conducted in Kiswahili, audio-recorded, transcribed and translated into English. Grounded theory approach was used to analyse transcripts. Open and selective coding was performed using Nvivo software.

RESULTS

FSWs reported that sex work impedes good contraceptive behaviour because sex workers felt unable to negotiate consistent condom use, avoided health services due to stigma, missed monthly contraceptive supplies because of inconvenient clinic operating hours or skipped contraceptive pills when intoxicated after taking alcohol. FSWs who perceived pregnancy to be a burden terminated the pregnancy because of fear of loss of income during pregnancy or child rearing expenses in case child support was not assured by their partners. FSWs who perceived pregnancy to be a blessing decided to keep the pregnancy because they desired motherhood and hoped that children would bring prosperity. Family planning counselling and availability of contraceptives during postpartum care influenced the initiation of contraception among FSWs. Financial hardships related to childrearing or painful abortion experiences influenced FSWs' commitment to good contraceptive practices.

CONCLUSION

Our results demonstrate that FSWs face barriers to initiating and adhering to contraceptive use because of sex work stigma, inability to negotiate condoms and failure to access medical services at their convenience. Our findings underscore the need to integrate contraceptive services with HIV programs serving FSWs in their areas of work.

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.

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.

Addressing the workforce capacity for public health surveillance through field epidemiology and laboratory training program: the need for balanced enhanced skill mix and distribution, a case study from Tanzania

Introduction

Skill mix refers to the range of professional development and competencies, skills and experiences of staff within a particular working environment that link with specific outcome while responding to client needs. A balanced skill-mix and distribution of core human resources is important to strengthen decision-making process and rapid responses. We analysed graduates´ information of the Tanzania Field Epidemiology and Laboratory Training Program (TFELTP) between 2008-2016, distribution of skill-mix and the surveillance workforce-gaps within regions.

Methods

Trainees´ data of nine cohorts enrolled between 2008 and 2016 were extracted from the program database. Distribution by sex, region and cadres/profession was carried out. An indicator to determine enhanced-skill mix was established based on the presence of a clinician, nurse, laboratory scientist and environmental health officer. A complete enhanced skill-mix was considered when all four were available and have received FELTP training.

Results

The TFELTP has trained 113 trainees (male=71.7%), originated from 17 regions of Tanzania Mainland (65.4% of all) and Zanzibar. Clinicians (34.5%) and laboratory scientists (38.1%) accounted for the most recruits, however, the former were widely spread in regions (83% vs. 56%). Environmental health officers (17.7%) were available in 39% of regions. The nursing profession, predominantly lacking (6.2%) was available in 22% of regions. Only two regions (11.7%) among 17 covered by TFELTP presented complete skill-mix, representing 7.7% of Tanzanian regions. Seven regions (41%) had an average of one trainee.

Conclusion

The TFELTP is yet to reach the required skill-mix in many regions within the country. The slow fill-rate for competent and key workforce cadres might impede effective response. Strategies to increase program awareness at subnational levels is needed to improve performance of surveillance and response system in Tanzania.

Skin disorders among children living in orphanage centres in Dar es Salaam, Tanzania

Background

Skin conditions contribute significantly to the global burden of diseases and are among the leading causes of non-fatal disease burden. Children living in orphanage centres are vulnerable to several conditions including dermatological disorders, and there is limited data on the burden of these conditions among orphans in Tanzania. This study was carried out to determine the pattern of dermatological conditions and contributing factors among orphans in Dar es Salaam, Tanzania.

Methodology

A cross-sectional study was conducted among 420 children aged less than 18 years from 12 orphanage centres in Dar es Salaam. Guided interviews using structured questionnaires were carried out to obtain socio-demographic and clinical data from participants. Clinical examination was performed for each participant and whenever indicated skin scrapings and biopsy were obtained.

Results

Four hundred and twenty participants were recruited out of which 281 (66.9%) were male, mean and median ages of participants were 11 ± 3.7 and 12 years, respectively. Two hundred and twenty-five (53.6%) participants were aged between 6 and12 years. Proportion of children with dermatological manifestations among participants was 57.4%. Two hundred and ninety-six diagnoses were made comprising of 192 (64.9%) infections and 104 (35.1%) non-infectious conditions. Tinea capitis was the commonest infection while acne vulgaris was the most common non-infectious condition. Proportionately more male children were affected as compared to female ones, p = 0.006.

Conclusion

Skin conditions are common among children living in orphanage centres in Dar es Salaam. Infectious conditions were predominant conditions and male children were more affected than female children. Reducing crowding and improving hygienic practices in these centres will be important in reducing the burden of these conditions.

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.

Perception of potential harm and benefits of HIV vaccine trial participation: A qualitative study from urban Tanzania

BACKGROUND

The development of an effective preventive HIV vaccine is the best-known option to halt incident HIV infections. Participants in HIV vaccine trials may possess expectations shaped by existing socio-cultural contexts that are important to understand to allow for improved trial design. Here, we describe post-phase I/II HIV vaccine trial perceptions within participating communities in Dar es Salaam, Tanzania.

MATERIALS AND METHODS

This descriptive qualitative study was conducted in May 2016. We conducted eight focus group discussions, each consisting of 5 to 12 participants. Four groups comprised of the past phase I/II HIV vaccine trial participants and four groups involved those who did not participate. We used a thematic analysis approach.

RESULTS

Ongoing concerns existed among non-vaccine trial participants who believed that those who participated in HIV vaccine trials were infected with HIV. Limited post-HIV vaccine trial result dissemination, the pre-existing negative beliefs about vaccines, and experiences from other previous medical experiments fueled these concerns. The participants anticipated that broader dissemination of facts regarding HIV vaccine trials using media, former volunteers, and flyers would reduce the reported concerns. In contrast, some participants embraced the benefits gained through participating in HIV vaccine trials. HIV vaccine trial participants appreciated trial interventions, such as health status check-ups, knowledge acquisition, and facilitation of access to medical services. They envisioned mutual benefits in the form of community protection and capacity building among the local scientists.

CONCLUSIONS

The future conduct of HIV vaccine trials in Tanzania requires wider community dissemination of information and post-trial feedback to alleviate concerns among the participating communities. Interventions such as medical services may represent essential incentives to the HIV vaccine trial volunteers. In future HIV vaccine trials, it is crucial to boost individual and perceived mutual benefits.

Envelope-Specific Recognition Patterns of HIV Vaccine-Induced IgG Antibodies Are Linked to Immunogen Structure and Sequence

Background: A better understanding of the parameters influencing vaccine-induced IgG recognition of individual antigenic regions and their variants within the HIV Envelope protein (Env) can help to improve design of preventive HIV vaccines.

Methods: Env-specific IgG responses were mapped in samples of the UKHVC003 Standard Group (UK003SG, n = 11 from UK) and TaMoVac01 (TMV01, n = 17 from Tanzania) HIV vaccine trials. Both trials consisted of three immunizations with DNA, followed by two boosts with recombinant Modified Vaccinia Virus Ankara (MVA), either mediating secretion of gp120 (UK003SG) or the presentation of cell membrane bound gp150 envelopes (TMV01) from infected cells, and an additional two boosts with 5 μg of CN54gp140 protein adjuvanted with glucopyranosyl lipid adjuvant (GLA). Env immunogen sequences in UK003SG were solely based on the clade C isolate CN54, whereas in TMV01 these were based on clades A, C, B, and CRF01AE. The peptide microarray included 8 globally representative Env sequences, CN54gp140 and the MVA-encoded Env immunogens from both trials, as well as additional peptide variants for hot spots of immune recognition.

Results: After the second MVA boost, UK003SG vaccinees almost exclusively targeted linear, non-glycosylated antigenic regions located in the inter-gp120 interface. In contrast, TMV01 recipients most strongly targeted the V2 region and an immunodominant region in gp41. The V3 region was frequently targeted in both trials, with a higher recognition magnitude for diverse antigenic variants observed in the UK003SG (p < 0.0001). After boosting with CN54gp140/GLA, the overall response magnitude increased with a more comparable recognition pattern of antigenic regions and variants between the two trials. Recognition of most immunodominant regions within gp120 remained significantly stronger in UK003SG, whereas V2-region recognition was not boosted in either group.

Conclusions: IgG recognition of linear antigenic Env regions differed between the two trials particularly after the second MVA boost. Structural features of the MVA-encoded immunogens, such as secreted, monomeric gp120 vs. membrane-anchored, functional gp150, and differences in prime-boost immunogen sequence variability most probably contributed to these differences. Prime-boosting with multivalent Env immunogens during TMV01 did not improve variant cross-recognition of immunodominant peptide variants in the V3 region.

Pre- and post-natal macronutrient supplementation for HIV-positive women in Tanzania: Effects on infant birth weight and HIV transmission

OBJECTIVE

To determine if a protein-calorie supplement (PCS) plus a micronutrient supplement (MNS) improves outcomes for HIV-infected lactating women and their infants.

DESIGN

Randomized, controlled trial.

SETTING

Dar es Salaam, Tanzania.

SUBJECTS, PARTICIPANTS

Pregnant HIV-infected women enrolled in PMTCT programs who intended to breastfeed for 6 months.

INTERVENTION

Randomization 1:1 to administration of a PCS plus MNS versus MNS alone among 96 eligible women beginning in the third trimester and continuing for 6 months of breast-feeding.

MAIN OUTCOME MEASURE(S)

Primary: infant weight at 3 months. Secondary: maternal BMI at 6 months.

RESULTS

PCS resulted in significant increases in daily energy intake compared to MNS at all time points (range of differences: +388-719 Kcal); and increases in daily protein intake (range of differences: +22-33 gm). Infant birth weight (excluding twins) was higher in the PCS than MNS groups: 3.30 kg vs 3.04 kg (p = 0.04). Infant weight at 3 months did not differ between PCS and MNS groups: 5.63 kg vs 5.99 kg (p = 0.07). Maternal BMI at 6 months did not differ between PCS and MNS groups: 24.3 vs 23.8 kg/m2 (p = 0.68). HIV transmission occurred in 0 infants in the PCS group vs 4 in the MNS group (p = 0.03).

CONCLUSIONS

In comparison to MNS the PCS + MNS intervention was well tolerated, increased maternal energy and protein intake, and increased infant birth weight, but not weight at 3 months or maternal BMI at 6 months. Reduced infant HIV transmission in the PCS + MNS group was observed.

TRIAL REGISTRATION

Clinical Trials.Gov NCT01461863.

Outbreak of an acute aflatoxicosis in Tanzania during 2016

In June 2016, an outbreak of an unknown disease was reported to affect clusters of families in two regions of the central part of Tanzania. A rapid epidemiological survey was conducted in the affected villages, with a detailed house-to-house survey in selected households. A total of 68 cases occurred between 14 May and 14 November 2016, of which 20 died, making a case fatality rate of 30%. Over 50% of the cases were below the age of 15 years. The cases presented with jaundice (n=60), abdominal pain (n=59), vomiting (n=56), diarrhoea (n=34) and ascites (n=32). The responsible food item appeared to be home grown maize. The rate ratio indicated that the occurrence of illnesses was associated with ingestion of food contaminated with high levels of aflatoxins (contamination range: 10-51,100 μg/kg and 2.4-285 μg/kg for case and control households, respectively). Serum aflatoxin biomarker indicated that cases were more likely to have higher than 1000 pg/mg aflatoxin-albumin adduct level in their sera compared to controls (Odds Ratio = 13.5; 95% confidence intervals = 1.5-165.3; range of aflatoxin-albumin adduct level = 36- 32,800 pg/mg for cases and 10-4020 pg/mg for controls). Beside aflatoxins, maize samples were also contaminated with high levels of fumonisins (range of contamination; 945-12,630 μg/kg) with 8 of 10 samples analysed from case households co-contaminated with both toxins at levels above the maximum limit of 5 or 10 μg/kg set for AFB1 or total aflatoxins and 2,000 μg/kg for fumonisins. Clinical presentation and high levels of aflatoxin in food samples coupled with high levels of serum aflatoxin-albumin adducts among the cases support the causal role of aflatoxins.

Gender aspects on HIV prevention efforts and participation in HIV vaccine trials among Police officers in Dar es Salaam, Tanzania

Background

For more than three decades, Human Immunodeficiency Virus (HIV) infection and Acquired Immune Deficiency Syndrome (AIDS) continue to dominate the health agenda. In sub-Saharan African countries, women are at more risk of contracting HIV and AIDS compared with men due to biological, social, economic, socio-economic and cultural factors. Women in the uniformed services may be more vulnerable to HIV/AIDS because of their work context, mobility, age and other factors that expose them to a higher risk of infection than women in the general population. This article describes gender dimensions, motives and challenges towards HIV prevention amongst Police officers (POs) in Dar es Salaam, Tanzania.

Methods

This was a descriptive qualitative study conducted at Police stations in Dar es Salaam, Tanzania. Fifteen in-depth interviews were conducted on POs; seven men, and eight women. Content analysis approach was used to analyze data.

Results

Participants’ self-descriptions shed light on gender differences in relation to self -perceptions, job contexts, sexual relationships and HIV prevention. Both men and women perceived themselves as role models, and believed that the surrounding community perceived the same. Safe sexual behavior appeared crucial to avoid undesirable health outcomes. Risky sexual practices were considered avoidable. Under unavoidable sexual temptations, women in particular would be keen to avoid risky sexual practices. Some participants expressed positive views towards condoms use during extra-marital sexual relationships, while others had negative opinions. Early phases of HIV vaccine trials appeared to gain support from sexual partners. However, condom use during phase I/II HIV vaccine trials was deemed as difficult. Support from the spouse was reported to influence condom use outside the wedlock. However, religious beliefs, socio-cultural issues and individual reasons were perceived as difficulties to promote condoms use.

Conclusions

These findings increase understanding of gender differences and context specific efforts towards HIV prevention. Individuals’ assertiveness against risky sexual practices and the intention to participate in HIV vaccine trials to develop an effective vaccine are worth noting. Nevertheless, uncertainties towards condoms use underscore the importance of condoms’ marketing particularly in extra marital sexual relationships and during early HIV vaccine trials.

Neuropsychiatric manifestations among HIV-1 infected African patients receiving efavirenz-based cART with or without tuberculosis treatment containing rifampicin

Purpose

Efavirenz-based combination antiretroviral therapy (cART) is associated with neuropsychiatric adverse events. We investigated the time to onset, duration, clinical implications, impact of pharmacogenetic variations, and anti-tuberculosis co-treatment on efavirenz-associated neuropsychiatric manifestations.

Methods

Prospective cohort study of cART naïve HIV patients with or without tuberculosis (HIV-TB) co-infection treated with efavirenz-based cART. Rifampicin-based anti-tuberculosis therapy was initiated 4 weeks prior to efavirenz-based cART in HIV-TB patients. Data on demographic, clinical, laboratory, and a 29-item questionnaire on neuropsychiatric manifestations were collected for 16 weeks after cART initiation. Genotyping for CYP2B6, CYP3A5, SLCO1B1, and ABCB1 and quantification of efavirenz plasma concentration were done on the 4th and 16th week.

Results

Data from 458 patients (243 HIV-only and 215 HIV-TB) were analyzed. Overall incidence of neuropsychiatric manifestations was 57.6% being higher in HIV-only (66.7%) compared to HIV-TB patients (47.4%) (p < 0.01). HIV-only patients were more symptomatic, with proportionately higher grades of manifestations compared to HIV-TB patients. Median time to manifestations was 1 week after cART initiation in HIV-only and 6 weeks after anti-TB (i.e., 2 weeks after cART initiation) in HIV-TB patients. HIV-only patients had significantly higher efavirenz plasma concentrations at 4 weeks after cART compared to HIV-TB patients. No association of sex or genotype was seen in relation to neuropsychiatric manifestations. Risk for neuropsychiatric manifestations was three times more in HIV-only patients compared to HIV-TB (p < 0.01).

Conclusions

Incidence of neuropsychiatric manifestations during early initiation of efavirenz-based cART is high in Tanzanian HIV patients. Risk of neuropsychiatric manifestations is lower in HIV patients co-treated with rifampicin containing anti-TB compared to those treated with efavirenz-based cART only.

Electronic supplementary material

The online version of this article (10.1007/s00228-018-2499-0) contains supplementary material, which is available to authorized users.

Developing a multisectoral National Action Plan for Health Security (NAPHS) to implement the International Health Regulations (IHR 2005) in Tanzania

The Ebola outbreak in West Africa precipitated a renewed momentum to ensure global health security through the expedited and full implementation of the International Health Regulations (IHR) (2005) in all WHO member states. The updated IHR (2005) Monitoring and Evaluation Framework was shared with Member States in 2015 with one mandatory component, that is, States Parties annual reporting to the World Health Assembly (WHA) on compliance and three voluntary components: Joint External Evaluation (JEE), After Action Reviews and Simulation Exercises. In February 2016, Tanzania, was the first country globally to volunteer to do a JEE and the first to use the recommendations for priority actions from the JEE to develop a National Action Plan for Health Security (NAPHS) by February 2017. The JEE demonstrated that within the majority of the 47 indicators within the 19 technical areas, Tanzania had either 'limited capacity' or 'developed capacity'. None had 'sustainable capacity'. With JEE recommendations for priority actions, recommendations from other relevant assessments and complementary objectives, Tanzania developed the NAPHS through a nationwide consultative and participatory process. The 5-year cost estimate came out to approximately US$86.6 million (22 million for prevent, 50 million for detect, 4.8 million for respond and 9.2 million for other IHR hazards and points of entry). However, with the inclusion of vaccines for zoonotic diseases in animals increases the cost sevenfold. The importance of strong country ownership and committed leadership were identified as instrumental for the development of operationally focused NAPHS that are aligned with broader national plans across multiple sectors. Key lessons learnt by Tanzania can help guide and encourage other countries to translate their JEE priority actions into a realistic costed NAPHS for funding and implementation for IHR (2005).

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.

Cost-Effectiveness of isoniazid preventive therapy among HIV-infected patients clinicaly screened for latent tuberculosis infection in Dar es Salaam, Tanzania: A prospective Cohort study

Background

One of the reasons why Isoniazid preventive therapy (IPT) for Tuberculosis (TB) is not widely used in low income countries is concerns on cost of excluding active TB. We analyzed the cost-effectiveness of IPT provision in Tanzania having ruled out active TB by a symptom-based screening tool.

Methods

Data on IPT cost-effectiveness was prospectively collected from an observational cohort study of 1283 HIV-infected patients on IPT and 1281 controls; followed up for 24 months. The time horizon for the analysis was 2 years. Number of TB cases prevented and deaths averted were used for effectiveness. A micro costing approach was used from a provider perspective. Cost was estimated on the basis of clinical records, market price or interviews with medical staff. We annualized the cost at a discount of 3%. A univariate sensitivity analysis was done. Results are presented in US$ at an average annual exchange rate for the year 2012 which was Tanzania shillings 1562.4 for 1 US $.

Results

The number of TB cases prevented was 420/100,000 persons receiving IPT. The number of deaths averted was 979/100,000 persons receiving IPT. Incremental cost due to IPT provision was US$ 170,490. The incremental cost effective ratio was US $ 405.93 per TB case prevented and US $ 174.15 per death averted. These costs were less than 3 times the 768 US $ Gross Domestic Product (GDP) per capita for Tanzania in the year 2014, making IPT provision after ruling out active TB by the symptom-based screening tool cost-effective. The results were robust to changes in laboratory and radiological tests but not to changes in recurrent, personnel, medication and utility costs.

Conclusion

IPT should be given to HIV-infected patients who screen negative to symptom-based TB screening questionnaire. Its cost-effectiveness supports government policy to integrate IPT to HIV/AIDS care and treatment in the country, given the availability of budget and the capacity of health facilities.

Boosting with Subtype C CN54rgp140 Protein Adjuvanted with Glucopyranosyl Lipid Adjuvant after Priming with HIV-DNA and HIV-MVA Is Safe and Enhances Immune Responses: A Phase I Trial

Background

A vaccine against HIV is widely considered the most effective and sustainable way of reducing new infections. We evaluated the safety and impact of boosting with subtype C CN54rgp140 envelope protein adjuvanted in glucopyranosyl lipid adjuvant (GLA-AF) in Tanzanian volunteers previously given three immunizations with HIV-DNA followed by two immunizations with recombinant modified vaccinia virus Ankara (HIV-MVA).

Methods

Forty volunteers (35 vaccinees and five placebo recipients) were given two CN54rgp140/GLA-AF immunizations 30–71 weeks after the last HIV-MVA vaccination. These immunizations were delivered intramuscularly four weeks apart.

Results

The vaccine was safe and well tolerated except for one episode of asymptomatic hypoglycaemia that was classified as severe adverse event. Two weeks after the second HIV-MVA vaccination 34 (97%) of the 35 previously vaccinated developed Env-specific binding antibodies, and 79% and 84% displayed IFN-γ ELISpot responses to Gag and Env, respectively. Binding antibodies to subtype C Env (included in HIV-DNA and protein boost), subtype B Env (included only in HIV-DNA) and CRF01_AE Env (included only in HIV-MVA) were significantly boosted by the CN54rgp140/GLA-AF immunizations. Functional antibodies detected using an infectious molecular clone virus/peripheral blood mononuclear cell neutralization assay, a pseudovirus/TZM-bl neutralization assay or by assays for antibody-dependent cellular cytotoxicity (ADCC) were not significantly boosted. In contrast, T-cell proliferative responses to subtype B MN antigen and IFN-γ ELISpot responses to Env peptides were significantly enhanced. Four volunteers not primed with HIV-DNA and HIV-MVA before the CN54rgp140/GLA-AF immunizations mounted an antibody response, while cell-mediated responses were rare. After the two Env subtype C protein immunizations, a trend towards higher median subtype C Env binding antibody titers was found in vaccinees who had received HIV-DNA and HIV-MVA prior to the two Env protein immunizations as compared to unprimed vaccinees (p = 0.07).

Conclusion

We report excellent tolerability, enhanced binding antibody responses and Env-specific cell-mediated immune responses but no ADCC antibody increase after two immunizations with a subtype C rgp140 protein adjuvanted in GLA-AF in healthy volunteers previously immunized with HIV-DNA and HIV-MVA.

Trial Registration

International Clinical Trials Registry PACTR2010050002122368

Motivations to participate in a Phase I/II HIV vaccine trial: A descriptive study from Dar es Salaam, Tanzania

Background

The search for an efficacious HIV vaccine is a global priority. To date only one HIV vaccine trial (RV144) has shown modest efficacy in a phase III trial. With existing different HIV-1 subtypes and frequent mutations, multiple trials are needed from different geographical sites particularly in sub-Saharan Africa where most HIV infections occur. Thus, motivations to participate in HIV vaccine trials among Tanzanians need to be assessed. This paper describes the motives of Police Officers who showed great interest to volunteer in HIVIS-03 in Dar es Salaam, Tanzania.

Methods

A descriptive cross-sectional study was conducted among Police Officers who showed interest to participate in the HIVIS-03, a phase I/II HIV vaccine trial in Dar es Salaam. Prior to detailed training sessions about HIV vaccine trials, the potential participants narrated their individual motives to participate in the trial on a piece of paper. Descriptive analysis using content approach and frequency distributions were performed.

Results

Of the 265 respondents, 242 (91.3 %) provided their socio-demographic characteristics as well as reasons that would make them take part in the proposed trial. Majority, (39.7 %), cited altruism as the main motive. Women were more likely to volunteer due to altruism compared to men (P < 0.01). Researchers’ explanations about HIV/AIDS vaccine studies motivated 15.3 %. More men (19.6 %) than women (1.7 %) were motivated to volunteer due to researchers’ explanations (P < 0.001). Also, compared to other groups, those unmarried and educated up to secondary level of education were motivated to volunteer due to researchers’ explanation (P < 0.05). Other reasons were: desire to become a role model (18.6 %); to get knowledge for educating others (14.0 %); to cooperate with researchers in developing an HIV vaccine (9.5 %); to get protection against HIV infection (7.0 %), and severity of the disease within families (6.2 %). These results were supported by testimonies from both men and women.

Conclusions

Participation in an HIV vaccine trial in a Tanzanian context is likely to be influenced by altruism and comprehensive education about the trial. Gender differences, marital status and education level need to be considered to enhance participation in future HIV vaccine trials.

Key considerations in scaling up male circumcision in Tanzania: views of the urban residents in Tanzania

Male circumcision (MC) reduces the risk of sexually transmitted infections (STI) including HIV. The WHO and UNAIDS recommend male circumcision as an additional intervention to prevent HIV infection. Tanzania is embarking on activities to scale up safe male circumcision for HIV prevention and other related health benefits. In line with this, it is crucial to assess views of the population using specific groups. This paper describes perceptions on male circumcision and strategies of enhancing uptake of male circumcision in urban Tanzania using members of the police force. This cross sectional survey was conducted among members of the police force in Dar es Salaam Tanzania from January 2010 to July 2010. The police officer serves as a source of the clinical trial participants in on-going phase I/II HIV vaccine trials. Three hundred and thirteen (313) police officers responded to a self-administered questionnaire that comprised of socio-demographic characteristics, reasons for not circumcising, perceptions regarding circumcision, methods of enhancing male circumcision, communication means and barriers to promote circumcision. This was followed by a physical examination to determine male circumcision status. The prevalence of circumcision was 96%. Most (69%) reported to have been circumcised in the hospital. The reported barriers to male circumcision among adults and children were: anticipation of pain, cost, fear to lose body parts, and lack of advice for adult's circumcision. Sensitization of parents who take children to the reproductive and child health services was recommended by most respondents as the appropriate strategy to promote male circumcision. The least recommended strategy was for the women to sensitize men. Use of radio programs and including male circumcision issues in school curricula as means of enhancing community sensitization regarding male circumcision were also highly recommended. Other recommendations include use of public media, seminars at work and issuance of circumcision regulations by health authorities. In conclusion, the present study reveals male circumcision was common in a selected urban population. There are various barriers and channels of communication regarding male circumcision. In view of scaling male circumcision in Tanzania, use of radio messages, inclusion of male circumcision in the school curricula and sensitization at the reproductive and child health clinics are likely to promote early medical male circumcision.

Factors associated with, and echocardiographic findings of heart failure among HIV infected patients at a tertiary health care facility in Dar es Salaam, Tanzania

Cardiovascular diseases, including heart failure are a known complication of Human Immunodeficiency Virus (HIV) infection globally. The objective of this study was to describe factors associated with, and echocardiographic findings of heart failure among HIV infected patients at a tertiary health care facility in Dar es Salaam, Tanzania. Clinical, laboratory and echocardiographic assessment was performed in all HIV-infected patients presenting with cardiac complaints at the medical department, Muhimbili National Hospital between September 2009 and April 2010. HF was diagnosed clinically and confirmed by echocardiography. Of the 102 HIV-infected patients with cardiac complaints 50 (49%) were in HF. Commonest causes of HF were hypertensive heart disease, pulmonary hypertension and dilated cardiomyopathy. In multivariate analysis male gender (OR 4.03), low education (OR 4.91), previous history of tuberculosis (OR 3.01), and low haemoglobin (OR 0.83), were independently associated with the diagnosis of HF (p<0.05 for all). In conclusion, heart failure is common in HIV-infected patients with cardiac complaints, and is associated with both modifiable and non-modifiable factors.

Acceptability and adherence to Isoniazid preventive therapy in HIV-infected patients clinically screened for latent tuberculosis in Dar es Salaam, Tanzania

Background

Proper adherence to isoniazid preventive therapy (IPT) may depend upon the results of tuberculosis (TB) screening test and patients’ understanding of their risk of developing active TB. We conducted a study to assess the acceptability, adherence and completion profile of IPT among HIV-infected patients who were clinically screened for latent TB Infection (LTBI).

Methods

A multicenter observational study was conducted in Dar es Salaam, Tanzania between February 2012 and March 2014. HIV-infected patients 10 years or older were clinically screened using a validated symptom-based screening tool to rule out active TB. Patients found to have no symptoms in the screening tool were given 300 mg of isoniazid (INH) daily for 6 months. Patients were followed up monthly at the National and Municipal hospital HIV clinics for INH refill and assessment of treatment adherence. Adherence was defined as consumption of 90 % or more of the monthly prescription of INH.

Results

All 1303 invited patients agreed to participate in the study. Of 1303 invited HIV-infected patients, 1283 (98.5 %) were recruited into the study. Twenty eight (2.2 %) did not complete treatment. Those who did not complete the treatment were exclusively adults aged 18 years or older, p = 0.302. The overall mean (±SD) adherence was 98.9 % (±2.9). Adherence level among children aged <18 years (92.2 %) was significantly lower than adherence level among patients aged 18–29 years (98.3 %), 30–49 years (98.8 %) and ≥ 50 years (98.5), p-value = 0.011. Sex, occupation, socio-economic status, duration of HIV infection, being on antiretroviral drugs (ARV) and duration of ARV use were not associated with adherence.

Conclusion

IPT is highly accepted by HIV infected patients. Patients demonstrated high level of adherence to IPT. The level of adherence among children was slightly lower than that among adults. IPT non-completers were exclusively adults. Children might need adult supervision in taking IPT.

Potent functional antibody responses elicited by HIV-I DNA priming and boosting with heterologous HIV-1 recombinant MVA in healthy Tanzanian adults

Vaccine-induced HIV antibodies were evaluated in serum samples collected from healthy Tanzanian volunteers participating in a phase I/II placebo-controlled double blind trial using multi-clade, multigene HIV-DNA priming and recombinant modified vaccinia Ankara (HIV-MVA) virus boosting (HIVIS03). The HIV-DNA vaccine contained plasmids expressing HIV-1 gp160 subtypes A, B, C, Rev B, Gag A, B and RTmut B, and the recombinant HIV-MVA boost expressed CRF01_AE HIV-1 Env subtype E and Gag-Pol subtype A. While no neutralizing antibodies were detected using pseudoviruses in the TZM-bl cell assay, this prime-boost vaccination induced neutralizing antibodies in 83% of HIVIS03 vaccinees when a peripheral blood mononuclear cell (PBMC) assay using luciferase reporter-infectious molecular clones (LucR-IMC) was employed. The serum neutralizing activity was significantly (but not completely) reduced upon depletion of natural killer (NK) cells from PBMC (p=0.006), indicating a role for antibody-mediated Fcγ-receptor function. High levels of antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies against CRF01_AE and/or subtype B were subsequently demonstrated in 97% of the sera of vaccinees. The magnitude of ADCC-mediating antibodies against CM235 CRF01_AE IMC-infected cells correlated with neutralizing antibodies against CM235 in the IMC/PBMC assay. In conclusion, HIV-DNA priming, followed by two HIV-MVA boosts elicited potent ADCC responses in a high proportion of Tanzanian vaccinees. Our findings highlight the potential of HIV-DNA prime HIV-MVA boost vaccines for induction of functional antibody responses and suggest this vaccine regimen and ADCC studies as potentially important new avenues in HIV vaccine development.

Pharmacokinetic and pharmacogenomic modelling of the CYP3A activity marker 4β-hydroxycholesterol during efavirenz treatment and efavirenz/rifampicin co-treatment

OBJECTIVES

To assess the effect of the major efavirenz metabolizing enzyme (CYP2B6) genotype and the effects of rifampicin co-treatment on induction of CYP3A by efavirenz.

PATIENTS AND METHODS

Two study arms (arm 1, n = 41 and arm 2, n = 21) were recruited into this study. In arm 1, cholesterol and 4β-hydroxycholesterol were measured in HIV treatment-naive patients at baseline and then at 4 and 16 weeks after initiation of efavirenz-based antiretroviral therapy. In arm 2, cholesterol and 4β-hydroxycholesterol were measured among patients taking efavirenz during rifampicin-based tuberculosis (TB) treatment (efavirenz/rifampicin) just before completion of TB treatment and then serially following completion of TB treatment (efavirenz alone). Non-linear mixed-effect modelling was performed.

RESULTS

A one-compartment, enzyme turnover model described 4β-hydroxycholesterol kinetics adequately. Efavirenz treatment in arm 1 resulted in 1.74 (relative standard error = 15%), 3.3 (relative standard error = 33.1%) and 4.0 (relative standard error = 37.1%) average fold induction of CYP3A for extensive (CYP2B6*1/*1), intermediate (CYP2B6*1/*6) and slow (CYP2B6*6/*6) efavirenz metabolizers, respectively. The rate constant of 4β-hydroxycholesterol formation [mean (95% CI)] just before completion of TB treatment [efavirenz/rifampicin co-treatment, 7.40 × 10(-7) h(-1) (5.5 × 10(-7)-1.0 × 10(-6))] was significantly higher than that calculated 8 weeks after completion [efavirenz alone, 4.50 × 10(-7) h(-1) (4.40 × 10(-7)-4.52 × 10(-7))]. The CYP3A induction dropped to 62% of its maximum by week 8 of completion.

CONCLUSIONS

Our results indicate that efavirenz induction of CYP3A is influenced by CYP2B6 genetic polymorphisms and that efavirenz/rifampicin co-treatment results in higher induction than efavirenz alone.

Experiences of social harm and changes in sexual practices among volunteers who had completed a phase I/II HIV vaccine trial employing HIV-1 DNA priming and HIV-1 MVA boosting in Dar es Salaam, Tanzania

Background

Volunteers in phase I/II HIV vaccine trials are assumed to be at low risk of acquiring HIV infection and are expected to have normal lives in the community. However, during participation in the trials, volunteers may encounter social harm and changes in their sexual behaviours. The current study aimed to study persistence of social harm and changes in sexual practices over time among phase I/II HIV vaccine immunogenicity (HIVIS03) trial volunteers in Dar es Salaam, Tanzania.

Methods and Results

A descriptive prospective cohort study was conducted among 33 out of 60 volunteers of HIVIS03 trial in Dar es Salaam, Tanzania, who had received three HIV-1 DNA injections boosted with two HIV-1 MVA doses. A structured interview was administered to collect data. Analysis was carried out using SPSS and McNemars’ chi-square (χ2) was used to test the association within-subjects. Participants reported experiencing negative comments from their colleagues about the trial; but such comments were less severe during the second follow up visits (χ2 = 8.72; P<0.001). Most of the comments were associated with discrimination (χ2 = 26.72; P<0.001), stigma (χ2 = 6.06; P<0.05), and mistrust towards the HIV vaccine trial (χ2 = 4.9; P<0.05). Having a regular sexual partner other than spouse or cohabitant declined over the two follow-up periods (χ2 = 4.45; P<0.05).

Conclusion

Participants in the phase I/II HIV vaccine trial were likely to face negative comments from relatives and colleagues after the end of the trial, but those comments decreased over time. In this study, the inherent sexual practice of having extra sexual partners other than spouse declined over time. Therefore, prolonged counselling and support appears important to minimize risky sexual behaviour among volunteers after participation in HIV Vaccine trials.

Factors that influence the willingness of young adults in Dar es Salaam, Tanzania, to participate in phase I/II HIV vaccine trials

Background

HIV/AIDS continues to destroy the lives of young people especially in low-income countries. The inclusion of youths in HIV vaccine trials is of utmost importance in obtaining an effective vaccine that is acceptable to them.

Objective

To characterize the willingness of young adults in Tanzania to participate in an HIV vaccine trial and the factors that influence this willingness.

Design

Four hundred and fifty young adults who visited a youth-friendly Infectious Diseases Clinic (IDC) from February 2012 to September 2012 completed a self-administered questionnaire concerning sociodemographic information, their knowledge about and perception of HIV vaccine studies, and the availability of social support.

Results

Of our participants, 50.6% expressed willingness to participate in HIV vaccine trials, and this willingness was positively correlated with having some knowledge about HIV vaccine studies (AOR, 2.2; 95% CI: 1.4–3.4), a positive perception toward such studies (AOR, 2.3; 95% CI: 1.5–3.6), having a relationship with someone who could help them make a decision (AOR, 2.5; 95% CI: 1.3–4.9), and age at the time of sexual debut (AOR, 2.6; 95% CI 1.0–6.7) for 15- to 19-year-olds and (AOR, 2.7; 95% CI 1.0–7.1) for older participants.

Conclusions

The participants exhibited a moderate willingness to participate in HIV vaccine trials, which was associated with a positive perception of and some knowledge about such trials, having a relationship with someone who might influence their decision as well as age at time of sexual debut. More efforts should be made to inform the youths about specific HIV vaccine trials and related matters, as well as to engage significant others in the decision-making process.

Experiences on recruitment and retention of volunteers in the first HIV vaccine trial in Dar es Salam, Tanzania - the phase I/II HIVIS 03 trial

Background

Eventual control of HIV/AIDS is believed to be ultimately dependent on a safe, effective and affordable vaccine. Participation of sub-Saharan Africa in the conduct of HIV trials is crucial as this region still experiences high HIV incidences. We describe the experience of recruiting and retaining volunteers in the first HIV vaccine trial (HIVIS03) in Tanzania.

Methods

In this trial enrolled volunteers from amongst Police Officers (POs) in Dar es Salaam were primed with HIV-1 DNA vaccine at months 0, 1 and 3; and boosted with HIV-1 MVA vaccine at months 9 and 21. A stepwise education provision/sensitization approach was employed to eventual recruitment. Having identified a “core” group of POs keen on HIV prevention activities, those interested to participate in the vaccine trial were invited for a first screening session that comprised of provision of detailed study information and medical evaluation. In the second screening session results of the initial assessment were provided and those eligible were assessed for willingness to participate (WTP). Those willing were consented and eventually randomized into the trial having met the eligibility criteria. Voluntary participation was emphasized throughout.

Results

Out of 408 POs who formed the core group, 364 (89.0%) attended the educational sessions. 263 out of 364 (72.2%) indicated willingness to participate in the HIV vaccine trial. 98% of those indicating WTP attended the pre-screening workshops. 220 (85.0%) indicated willingness to undergo first screening and 177 POs attended for initial screenings, of whom 162 (91.5%) underwent both clinical and laboratory screenings. 119 volunteers (73.5%) were eligible for the study. 79 were randomized into the trial, while 19 did not turn up, the major reason being partner/family advice. 60 volunteers including 15 females were recruited during a one-year period. All participated in the planned progress updates workshops. Retention into the schedule was: 98% for the 3 DNA/placebo vaccinations, while it was 83% and 73% for the first and second MVA/placebo vaccinations respectively.

Conclusion

In this first HIV vaccine trial in Tanzania, we successfully recruited the volunteers and there was no significant loss to follow up. Close contact and updates on study progress facilitated the observed retention rates.

Trial registration numbers

ISRCTN90053831 ISRNCT01132976 and ATMR2009040001075080

Nutritional status of HIV-infected women with tuberculosis in Dar es Salaam, Tanzania

SETTING

Tuberculosis (TB) treatment clinics in Dar es Salaam, Tanzania.

OBJECTIVE

To quantify anthropometrics and intake of en-ergy and protein among human immunodeficiency virus (HIV) positive women with TB.

DESIGN

HIV-positive women with newly diagnosed TB were assessed on their anthropometric characteristics and dietary intake. Energy and protein intake were determined using Tanzania food composition tables and compared with standard recommendations. Patients were re-evaluated after 4-6 months of anti-tuberculosis treatment.

RESULTS

Among 43 women, the baseline median CD4 count was 209 cells/µl (range 8-721); 19 (44%) had a CD4 count of <200; 20 (47%) were on antiretroviral therapy. Body mass index was <18.5 kg/m(2) in 25 (58%); the median food insecurity score was 6. The median level of kcal/day was 1693 (range 1290-2633) compared to an estimated need of 2658; the median deficit was 875 kcal (range -65-1278). The median level of protein/day was 42 g (range 27-67) compared to 77 g estimated need; the median protein deficit was 35 g (range 10-50). The median weight gain among 29 patients after 4-6 months was 6 kg.

CONCLUSION

HIV-positive women with TB have substantial 24-h deficits in energy and protein intake, report significant food insecurity and gain minimal weight on anti-tuberculosis treatment. Enhanced dietary education together with daily supplementation of 1000 kcal with 40 g protein may be required.

A qualitative study of perceived risk for HIV transmission among police officers in Dar es Salaam, Tanzania

Background

Understanding people’s views about HIV transmission by investigating a specific population may help to design effective HIV prevention strategies. In addition, knowing the inherent sexual practices of such a population, as well as the risky circumstances that may facilitate HIV transmission, is crucial for the said strategies to become effective. In this article, we report how police officers in Dar es Salaam, Tanzania, perceived the problem of HIV and AIDS in their local context, particularly in relation to unsafe sexual practices. The study was done with the view to recommending ways by which HIV transmission could be minimised within the police force.

Methods

The study was conducted among members of the police force in Dar es Salaam, Tanzania. Eight focus group discussions (FGDs) were conducted, with a total of 66 participants who were mixed in terms of age, gender, and marital status. Some of these were caregivers to patients with AIDS. Data were analysed using the interpretive description approach.

Results

The participants believed that both individual sexual behaviour and work-related circumstances were sources of HIV infection. They also admitted that they were being tempted to engage in risky sexual practices because of the institutional rules that prohibit officers from getting married during their training and for three years after. Nevertheless, as members of the Police Force, they stressed the fact that the risky sexual behaviour that exposes them to HIV is not limited to the force; it is rather a common problem that is faced by the general population. However, they complained, the nature of their job exposes them to road accident victims, subjecting them further to possible infection, especially when they have to handle these road accident casualties without proper protective gear.

Conclusion

Individual sexual behaviour and job-related circumstances are worth investigating if proper advice is to be given to the police regarding HIV prevention strategies. In order to improve the lives of these police officers, there is a need to review the existing institutional rules and practices to accommodate individual sexual needs. In addition, improving their working environment may minimize the risk of HIV transmission from handling casualties in emergency situations.

Declining HIV-1 prevalence and incidence among Police Officers - a potential cohort for HIV vaccine trials, in Dar es Salaam, Tanzania

Background

A safe effective and affordable HIV vaccine is the most cost effective way to prevent HIV infection worldwide. Current studies of HIV prevalence and incidence are needed to determine potentially suitable cohorts for vaccine studies. The prevalence and incidence of HIV-1 infection among the police in Dar es Salaam in 1996 were 13.8% and 19.6/1000 PYAR respectively. This study aimed at determining the current prevalence and incidence of HIV in a police cohort 10 years after a similar study was conducted.

Methods

Police officers in Dar es Salaam, Tanzania were prospectively enrolled into the study from 2005 and followed-up in an incidence study three years later. HIV infection was determined by two sequential enzyme linked immunosorbent assays (ELISAs) in the prevalence study and discordant results between two ELISAs were resolved by a Western blot assay. Rapid HIV assays (SD Bioline and Determine) were used for the incidence study.

Results

A total of 1,240 police participated in the HIV prevalence study from August 2005 to November 2008. Of these, 1101 joined the study from August 2005-September 2007 and an additional 139 were recruited between October 2007 to November 2008 while conducting the incidence study. A total of 726 (70%) out of the 1043 eligible police participated in the incidence study.

The overall HIV-1 prevalence was 65/1240 (5.2%). Females had a non-statistically significant higher prevalence of HIV infection compared to males 19/253, (7.5%) vs. 46/987 (4.7%) respectively (p = 0.07). The overall incidence of HIV-1 was 8.4 per 1000 PYAR (95% CI 4.68-14.03), and by gender was 8.8 and 6.9 per 1000 PYAR, among males and females respectively, (p = 0.82).

Conclusions

The HIV prevalence and incidence among the studied police has declined over the past 10 years, and therefore this cohort is better suited for phase I/II HIV vaccine studies than for efficacy trials.

Greater preexisting interferon γ responses to mycobacterial antigens and lower bacillary load during HIV-associated tuberculosis

The role of preexisting interferon (IFN) γ responses in controlling bacillary burden in human immunodeficiency virus (HIV)-associated tuberculosis is not known. Among BCG-immunized HIV-infected adults who developed tuberculosis in a phase III trial of an investigational tuberculosis vaccine, greater baseline IFN-γ responses to early secretory antigenic target 6 and Mycobacterium tuberculosis whole-cell lysate were associated with reduced bacillary burden on sputum smear grade, days to culture positivity on agar, and sputum culture grade during subsequent tuberculosis. This association was most consistent among recipients of the investigational vaccine. When HIV-associated tuberculosis develops, greater preexisting IFN-γ responses to mycobacterial antigens are associated with reduced tuberculosis bacillary burden. ClinicalTrials.gov Identifier. NCT0052195.

Recurrent tuberculosis risk among HIV-infected adults in Tanzania with prior active tuberculosis

BACKGROUND

Active tuberculosis is common among human immunodeficiency virus (HIV)-infected persons living in tuberculosis-endemic areas, but the hazard of subsequent tuberculosis disease has not been quantified in a single prospective cohort.

METHODS

Among HIV-infected, BCG-immunized adults with CD4 counts ≥200 cells/μL who received placebo in the DarDar tuberculosis vaccine trial in Tanzania, we compared the prospective risk of active tuberculosis between subjects who did and who did not report prior active tuberculosis. All subjects with a positive tuberculin skin test without prior active tuberculosis were offered isoniazid preventive treatment. Definite or probable tuberculosis was diagnosed during active follow-up using rigorous published criteria.

RESULTS

We diagnosed 52 cases of definite and 92 cases of definite/probable tuberculosis among 979 subjects during a median follow-up of 3.2 years. Among the 80 subjects who reported prior active tuberculosis, 11 (13.8%) subsequently developed definite tuberculosis and 17 (21.3%) developed definite/probable tuberculosis, compared with 41 (4.6%) and 75 (8.3%), respectively, of 899 subjects without prior active tuberculosis (definite tuberculosis risk ratio [RR], 3.01; 95% confidence interval [CI], 1.61-5.63, P < .001; definite/probable tuberculosis RR, 2.55; 95% CI, 1.59-4.09, P < .001). In a Cox regression model adjusting for age, CD4 count, and isoniazid receipt, subjects with prior active tuberculosis had substantially greater hazard of subsequent definite tuberculosis (hazard radio [HR], 3.69; 95% CI, 1.79-7.63, P < .001) and definite/probable tuberculosis (HR, 2.78; 95% CI, 1.58-4.87, P < .001).

CONCLUSIONS

Compared to subjects without prior tuberculosis, the hazard of active tuberculosis is increased 3-fold among HIV-infected adults with prior active tuberculosis. Clinical Trials Registration. NCT0052195.

The perceptions on male circumcision as a preventive measure against HIV infection and considerations in scaling up of the services: a qualitative study among police officers in Dar es Salaam, Tanzania

Background

In recent randomized controlled trials, male circumcision has been proven to complement the available biomedical interventions in decreasing HIV transmission from infected women to uninfected men. Consequently, Tanzania is striving to scale-up safe medical male circumcision to reduce HIV transmission. However, there is a need to investigate the perceptions of male circumcision in Tanzania using specific populations. The purpose of the present study was to assess the perceptions of male circumcision in a cohort of police officers that also served as a source of volunteers for a phase I/II HIV vaccine (HIVIS-03) trial in Dar es Salaam, Tanzania.

Methods

In-depth interviews with 24 men and 10 women were conducted. Content analysis informed by the socio-ecological model was used to analyze the data.

Results

Informants perceived male circumcision as a health-promoting practice that may prevent HIV transmission and other sexually transmitted infections. They reported male circumcision promotes sexual pleasure, confidence and hygiene or sexual cleanliness. They added that it is a religious ritual and a cultural practice that enhances the recognition of manhood in the community. However, informants were concerned about the cost involved in male circumcision and cleanliness of instruments used in medical and traditional male circumcision. They also expressed confusion about the shame of undergoing circumcision at an advanced age and pain that could emanate after circumcision. The participants advocated for health policies that promote medical male circumcision at childhood, specifically along with the vaccination program.

Conclusions

The perceived benefit of male circumcision as a preventive strategy to HIV and other sexually transmitted infections is important. However, there is a need to ensure that male circumcision is conducted under hygienic conditions. Integrating male circumcision service in the routine childhood vaccination program may increase its coverage at early childhood. The findings from this investigation provide contextual understanding that may assist in scaling-up male circumcision in Tanzania.

Liver enzyme abnormalities and associated risk factors in HIV patients on efavirenz-based HAART with or without tuberculosis co-infection in Tanzania

Objectives

To investigate the timing, incidence, clinical presentation, pharmacokinetics and pharmacogenetic predictors for antiretroviral and anti-tuberculosis drug induced liver injury (DILI) in HIV patients with or without TB co-infection.

Methods and Findings

A total of 473 treatment naïve HIV patients (253 HIV only and 220 with HIV-TB co-infection) were enrolled prospectively. Plasma efavirenz concentration and CYP2B6*6, CYP3A5*3, *6 and *7, ABCB1 3435C/T and SLCO1B1 genotypes were determined. Demographic, clinical and laboratory data were collected at baseline and up to 48 weeks of antiretroviral therapy. DILI case definition was according to Council for International Organizations of Medical Sciences (CIOMS). Incidence of DILI and identification of predictors was evaluated using Cox Proportional Hazards Model. The overall incidence of DILI was 7.8% (8.3 per 1000 person-week), being non-significantly higher among patients receiving concomitant anti-TB and HAART (10.0%, 10.7per 1000 person-week) than those receiving HAART alone (5.9%, 6.3 per 1000 person-week). Frequency of CYP2B6*6 allele (p = 0.03) and CYP2B6*6/*6 genotype (p = 0.06) was significantly higher in patients with DILI than those without. Multivariate cox regression model indicated that CYP2B6*6/*6 genotype and anti-HCV IgG antibody positive as significant predictors of DILI. Median time to DILI was 2 weeks after HAART initiation and no DILI onset was observed after 12 weeks. No severe DILI was seen and the gain in CD4 was similar in patients with or without DILI.

Conclusions

Antiretroviral and anti-tuberculosis DILI does occur in our setting, presenting early following HAART initiation. DILI seen is mild, transient and may not require treatment interruption. There is good tolerance to HAART and anti-TB with similar immunological outcomes. Genetic make-up mainly CYP2B6 genotype influences the development of efavirenz based HAART liver injury in Tanzanians.

New vaccines for the prevention of tuberculosis in human immunodeficiency virus infection

The prevention of human immunodeficiency virus (HIV) associated tuberculosis (TB) remains challenging. Several vaccines against TB have advanced to clinical trials in patients with HIV infection. The DarDar Trial, a large, randomized, placebo-controlled efficacy trial conducted in Tanzania, has demonstrated that a multiple dose series of an inactivated whole cell mycobacterial vaccine is safe in HIV and can prevent HIV-associated TB in patients with childhood bacille Calmette-Guérin vaccination and CD4 counts of ≥200 cells/mm(3). These developments offer promise that in the not too distant future immunization with an effective vaccine against TB can be added to other strategies for the prevention of HIV-associated TB. This expanded approach is referred to as the Five 'I's': intensified case finding, infection control, isoniazid preventive therapy (IPT), initiation of antiretroviral therapy (ART), and immunization against TB. We encourage additional studies of new TB vaccines in HIV, and propose a strategy to reduce the risk of TB by integrating IPT, ART and immunization into routine HIV care. At the time of HIV diagnosis, patients with CD4 counts of ≥200 cells/mm(3) could receive immunization, IPT and, as appropriate, ART. In patients presenting with lower CD4 counts or already on ART, immunization could be initiated at CD4 counts of ≥200 cells/mm(3) to add to the protection afforded by IPT and ART.