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1.
PLoS One ; 18(7): e0288604, 2023.
Article in English | MEDLINE | ID: mdl-37459311

ABSTRACT

INTRODUCTION: Hepatitis B (HBV) prevalence remains high in Sub Saharan Africa and among some key populations such as those with continued exposure through sexual contact. We assessed the HBV status among potential participants who were screened for simulated HIV vaccine efficacy trials in Kenya and Uganda. METHODS: We conducted a cross sectional analysis of data collected from individuals who were screened in Kenya (Nairobi) and Uganda (Entebbe and Kampala). The studies followed hypothetical procedures of an HIV vaccine efficacy trial and aimed to enroll HIV negative key and vulnerable populations at elevated risk of HIV acquisition. HBV status was the main outcome categorized using Hepatitis B surface antigen (HBsAg) and total Hepatitis B core antibody (HBcAb). Baseline characteristics potentially associated with never being infected were analyzed using logistic regression. RESULTS: We screened 1,366 participants with mean age (SD) 28.7 (7.3) years. Overall, 46.6% were from Entebbe, 50.7% had secondary or higher level of education, 76.4% had informal high-risk jobs and 56.3% were male. Kampala had only female participants contributing 60.6% of females screened. Of the screened participants, 94.7% and 3.4% were negative and positive for HBsAg respectively. The prevalence on HBV infection was 3.9% among males and 2.8% among females while prevalence by site was: Entebbe (4.9%); Kampala (4.1%) and Nairobi (0.3%). The highest HBV prevalence was found among participants aged 25-29-years (5.2%), those with primary level education (4.5%), and those in informal low risk jobs (6.5%). Considering 1265 participants with complete data on HBsAg and HBcAb-Total, HBV status was never infected (67.9%), past infection (28.5%), chronic infection (3.2%) and acute infection (0.5%). Of 859 who were never infected, 685 (79.7%) were tested for anti-HBs titers of whom 60 (8.8%) had titers >10IU/L (immune due to vaccination). The odds of never being HBV infected were lower among older individuals 25-29 years (AOR 0.51; 95%CI 0.36-0.71) and ≥30 years (AOR 0.35; 95% CI 0.25-0.49). The odds were higher among participants with informal high-risk jobs from Kampala (AOR 2.21; 95% CI 1.41-3.47) and Nairobi (AOR 2.61; 95% CI 1.72-4.00) compared to those from Entebbe. CONCLUSION: HBV prevalence and immunity due to vaccination were low among HIV negative individuals who are eligible for HIV vaccine trials and prevalence varies by age, education level and main occupation. Younger individuals and those recruited from existing cohorts/ clinics have a higher likelihood of having no prior HBV infection. HIV prevention intervention trials are a platform to identify individuals that need HBV vaccination.


Subject(s)
AIDS Vaccines , HIV Infections , Hepatitis B , Humans , Male , Female , Adult , Hepatitis B Surface Antigens , Uganda/epidemiology , Kenya/epidemiology , Cross-Sectional Studies , Vaccine Efficacy , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis B/complications , Hepatitis B virus , Hepatitis B Vaccines , Hepatitis B Antibodies , Prevalence , HIV Infections/epidemiology , HIV Infections/prevention & control , HIV Infections/complications
2.
PLoS Negl Trop Dis ; 17(7): e0011089, 2023 07.
Article in English | MEDLINE | ID: mdl-37406029

ABSTRACT

Schistosomiasis is a disease caused by parasitic flatworms of the Schistosoma spp., and is increasingly recognized to alter the immune system, and the potential to respond to vaccines. The impact of endemic infections on protective immunity is critical to inform vaccination strategies globally. We assessed the influence of Schistosoma mansoni worm burden on multiple host vaccine-related immune parameters in a Ugandan fishing cohort (n = 75) given three doses of a Hepatitis B (HepB) vaccine at baseline and multiple timepoints post-vaccination. We observed distinct differences in immune responses in instances of higher worm burden, compared to low worm burden or non-infected. Concentrations of pre-vaccination serum schistosome-specific circulating anodic antigen (CAA), linked to worm burden, showed a significant bimodal distribution associated with HepB titers, which was lower in individuals with higher CAA values at month 7 post-vaccination (M7). Comparative chemokine/cytokine responses revealed significant upregulation of CCL19, CXCL9 and CCL17 known to be involved in T cell activation and recruitment, in higher CAA individuals, and CCL17 correlated negatively with HepB titers at month 12 post-vaccination. We show that HepB-specific CD4+ T cell memory responses correlated positively with HepB titers at M7. We further established that those participants with high CAA had significantly lower frequencies of circulating T follicular helper (cTfh) subpopulations pre- and post-vaccination, but higher regulatory T cells (Tregs) post-vaccination, suggesting changes in the immune microenvironment in high CAA could favor Treg recruitment and activation. Additionally, we found that changes in the levels of innate-related cytokines/chemokines CXCL10, IL-1ß, and CCL26, involved in driving T helper responses, were associated with increasing CAA concentration. This study provides further insight on pre-vaccination host responses to Schistosoma worm burden which will support our understanding of vaccine responses altered by pathogenic host immune mechanisms and memory function and explain abrogated vaccine responses in communities with endemic infections.


Subject(s)
Schistosomiasis mansoni , Animals , Schistosomiasis mansoni/epidemiology , Antigens, Helminth , Schistosoma mansoni , Cytokines , Vaccination , Immunity
3.
medRxiv ; 2023 Feb 26.
Article in English | MEDLINE | ID: mdl-36865336

ABSTRACT

The impact of endemic infections on protective immunity is critical to inform vaccination strategies. In this study, we assessed the influence of Schistosoma mansoni infection on host responses in a Ugandan fishing cohort given a Hepatitis B (HepB) vaccine. Concentrations of schistosome-specific circulating anodic antigen (CAA) pre-vaccination showed a significant bimodal distribution associated with HepB titers, which were lower in individuals with high CAA. We established that participants with high CAA had significantly lower frequencies of circulating T follicular helper (cTfh) subpopulations pre- and post-vaccination and higher regulatory T cells (Tregs) post-vaccination. Polarization towards higher frequencies of Tregs: cTfh cells can be mediated by changes in the cytokine environment favoring Treg differentiation. In fact, we observed higher levels of CCL17 and soluble IL-2R pre-vaccination (important for Treg recruitment and development), in individuals with high CAA that negatively associated with HepB titers. Additionally, alterations in pre-vaccination monocyte function correlated with HepB titers, and changes in innate-related cytokines/chemokine production were associated with increasing CAA concentration. We report, that by influencing the immune landscape, schistosomiasis has the potential to modulate immune responses to HepB vaccination. These findings highlight multiple Schistosoma -related immune associations that could explain abrogated vaccine responses in communities with endemic infections. Author Summary: Schistosomiasis drives host immune responses for optimal pathogen survival, potentially altering host responses to vaccine-related antigen. Chronic schistosomiasis and co-infection with hepatotropic viruses are common in countries where schistosomiasis is endemic. We explored the impact of Schistosoma mansoni ( S. mansoni ) infection on Hepatitis B (HepB) vaccination of individuals from a fishing community in Uganda. We demonstrate that high schistosome-specific antigen (circulating anodic antigen, CAA) concentration pre-vaccination, is associated with lower HepB antibody titers post-vaccination. We show higher pre-vaccination levels of cellular and soluble factors in instances of high CAA that are negatively associated with HepB antibody titers post-vaccination, which coincided with lower frequencies of circulating T follicular helper cell populations (cTfh), proliferating antibody secreting cells (ASCs), and higher frequencies of regulatory T cells (Tregs). We also show that monocyte function is important in HepB vaccine responses, and that high CAA is associated with alterations in the early innate cytokine/chemokine microenvironment. Our findings suggest that in individuals with high CAA and likely high worm burden, schistosomiasis creates and sustains an environment that is polarized against optimal host immune responses to the vaccine, which puts many endemic communities at risk for infection against HepB and other diseases that are preventable by vaccines.

4.
BMC Health Serv Res ; 22(1): 506, 2022 Apr 14.
Article in English | MEDLINE | ID: mdl-35421987

ABSTRACT

INTRODUCTION: Family planning knowledge is poor and use is low in Ugandan fishing communities. We compared the effectiveness of enhanced family planning (FP) education with routine counselling on FP knowledge and use. METHODS: Individuals aged 15-49 years were randomly assigned to intervention or control arm. The intervention constituted enhanced FP education based on a simplified handout extracted from the WHO FP guidance tool called, "Family planning: A global handbook for FP providers" which participants took home for additional reading. The control arm constituted FP counselling following Uganda Ministry of Health guidelines. FP knowledge score and contraceptive prevalence rate (CPR) were compared between trial arms at baseline and at 12 months. Negative binomial regression models were used to estimate the effect of the intervention on FP knowledge and use. RESULTS: Overall, 1410 participants were screened to enrol 1004 (502 per study arm, 48.5% women). Subsequently, 384 (76.5%) and 383 (76.3%) completed the 12 months' follow-up in the intervention and control arms respectively. At baseline, a median FP knowledge score of 8 and a < 70% FP knowledge score was observed for all participants with a CPR of 36.8%. At month-12, the median FP knowledge score improved in both arms, higher in the intervention arm than the control arm (46 vs 30; p < 0.001). In the intervention arm, 304 (79.2%) had a score of ≥70 compared with 21 (5.5%) in the control arm (p < 0.001). In the negative binomial regression model, the change in FP knowledge score was 47% higher in the intervention arm than in the control arm (score ratio: 1.47, 95%CI: 1. 43-1.51, p < 0.001). The change in CPR was 16% higher in the intervention arm than in the control arm (Prevalence ratio: 1.16, 95%CI: 1.01-1.34, p < 0.040). INTERPRETATION: Enhanced FP education using a simplified FP education handout was more effective in increasing FP knowledge and use compared to routine FP counselling for people living in fishing communities. Innovative FP education interventions are recommended for improving FP knowledge and optimizing uptake in remote-rural settings where literacy levels are low. TRIAL REGISTRATION: The study was registered by the Pan African Clinical Trial Registry on 03 July 2021 with a Trial Registration Number PACTR202107891858045 . "Retrospectively registered".


Subject(s)
Family Planning Services , Sex Education , Contraceptive Agents , Female , Humans , Hunting , Lakes , Male , Uganda/epidemiology
5.
BMC Public Health ; 21(1): 394, 2021 02 23.
Article in English | MEDLINE | ID: mdl-33622281

ABSTRACT

INTRODUCTION: Hepatitis B is a serious potentially fatal hepatocellular disease caused by the hepatitis B virus. In the fishing communities of Lake Victoria Uganda, the hepatitis B virus infection burden is largely unknown. This study assessed the prevalence and incidence of hepatitis B in these communities. METHODS: This was a retrospective cohort study that tested serum samples collected from 13 to 49-year-old study participants that were residing in two Ugandan Lake Victoria fishing communities of Kasenyi (a mainland) and Jaana (an island). The samples were collected between 2013 and 2015 during the conduct of an HIV epidemiological cohort study in these communities. A total of 467 twelve-month follow-up and 50 baseline visit samples of participants lost to follow-up were tested for hepatitis B serological markers to determine prevalence. To determine hepatitis B virus incidence, samples that were hepatitis B positive at the follow-up visit had their baseline samples tested to identify hepatitis B negative samples whose corresponding follow-up samples were thus incident cases. RESULTS: The baseline mean age of the 517 study participants was 31.1 (SD ± 8.4) years, 278 (53.8%) of whom were females. A total of 36 (7%) study participants had hepatitis B virus infection, 22 (61.1%) of whom were male. Jaana had a higher hepatitis B virus prevalence compared to Kasenyi (10.2% vs 4.0%). In total, 210 (40.6%) study participants had evidence of prior hepatitis B virus infection while 48.6% had never been infected or vaccinated against this disease. A total of 20 (3.9%) participants had results suggestive of prior hepatitis B vaccination. Hepatitis B incidence was 10.5 cases/100PY (95% CI: 7.09-15.53). Being above 25 years of age and staying in Jaana were significant risk factors for hepatitis B virus acquisition (AOR 1.6, 95% CI: 1.1-2.2; p < 0.01 and 1.4, 95% CI: 1.1-1.8; p < 0.01 respectively). CONCLUSION: Hepatitis B virus incidence in Lake Victoria fishing communities of Uganda is very high, particularly in the islands. Interventions to lower hepatitis B virus transmission in these communities are urgently needed.


Subject(s)
HIV Infections , Hepatitis B , Adolescent , Adult , Cohort Studies , Female , Hepatitis B/epidemiology , Humans , Incidence , Islands , Lakes , Male , Middle Aged , Prevalence , Retrospective Studies , Uganda/epidemiology , Young Adult
6.
J Family Med Prim Care ; 10(11): 3968-3975, 2021 Nov.
Article in English | MEDLINE | ID: mdl-35136754

ABSTRACT

INTRODUCTION: In Uganda, people living in fishing communities tend to engage in high-risk sexual activity which leads to unintended pregnancies that may end in abortions. Abortion has negative social, psychological, and medical impacts. We determined the frequency of abortion and its correlates among female fisher-folk along Lake Victoria in Uganda. METHODS: A cross-sectional survey was conducted among women aged 15- 49 years from Kigungu and Nsazi fishing communities. Data were collected on socio-demographic characteristics, abortion, and family planning use. Associations between abortion and participant characteristics were assessed using logistic regression models. RESULTS: Of the 713 women interviewed, 36, 5% were pregnant and 247, 34.6 % were using contraception. Majority (600, 84.2%) of those interviewed reported ever being pregnant. Approximately 45% of the pregnancies were un-intended while a third of those who had ever been pregnant (195, 32.5%) reported having aborted before. Slightly over a third (247, 34.6%) reported currently using or ever using family planning. Women aged 30+ years were more likely to abort compared to those aged 15-29 years (aOR: 2.7; 95% CI: 1.23-5.91). Women who had living children were less likely to abort compared to those who didn't have any living child (aOR: 0.06; 95% CI: 0.01 - 0.17). CONCLUSION: The rate of abortion among female fisher-folk in Uganda is substantial. Family planning use is still low and unintended pregnancies are common. Abortion risk increased with the age of the mother. Continuous behavioral change communication and optimization of family planning use are recommended to reduce abortions.

7.
BMC Public Health ; 20(1): 1642, 2020 Nov 03.
Article in English | MEDLINE | ID: mdl-33143684

ABSTRACT

BACKGROUND: Knowledge of family planning (FP) is a key determinant of contraceptive use which ultimately plays a role in attainment of good health and in conduct of clinical research. People living in fishing communities (FCs) have limited access to health services including FP and are targeted for future clinical research but their knowledge of FP and its correlates are scantily known. We determined correlates of knowledge of FP among people living in FCs of L. victoria in Uganda to inform future FP education programs in FCs. METHODS: We conducted a comparative cross-sectional survey among participants aged 15-49 years from Kigungu and Nsazi. Participants were asked if they were aware of any FP method. All those who responded in the affirmative were further asked to mention what FP methods they had heard of or knew. Those who reported knowledge of at least one FP method were asked a series of questions about FP methods and their side effects. Knowledge was categorized into good or poor knowledge based on their mean total score. Poor knowledge constituted a score below the mean while good knowledge constituted a score of more than or equal to the mean total score. To further explore attitudes and perceptions of FP, ten in-depth interviews and four focus group discussions were conducted. RESULTS: Of the 1410 screened participants, 94.5% were aware of at least one FP method. Pills and injectable hormonal methods were the most commonly known methods. Slightly over a third (38%) had good knowledge of FP. Correlates of knowledge of FP were; being female (aOR: 1.92 95% CI: 1.39-2.67), residing in Kigungu (aOR: 4.01 95% CI: 2.77-5.81), being married (aOR: 1.59 95% CI: 1.11-2.28) and currently being in a sexual relationship (aOR: 1.75 95% CI: 1.18-2.60). Concerns about safety and effectiveness of some modern FP methods exist. Misconceptions on effects of FP like sterility, cancers and foetal abnormalities were common. CONCLUSION: FP awareness among people living in FCs of L. Victoria in Uganda is high. However, good knowledge about specific methods tends to be low. Correlates of knowledge of FP include gender, residence, marital status and sexual engagement.


Subject(s)
Family Planning Services , Lakes , Adolescent , Adult , Contraception Behavior , Cross-Sectional Studies , Female , Health Knowledge, Attitudes, Practice , Humans , Middle Aged , Uganda , Young Adult
8.
J Prim Care Community Health ; 11: 2150132720943775, 2020.
Article in English | MEDLINE | ID: mdl-32698653

ABSTRACT

Introduction: Family planning (FP) is a key element in the conduct of research and is essential in managing family sizes. Although fishing communities (FCs) are targeted populations for HIV prevention research, their FP practices are poorly understood. We explored barriers and facilitators of FP use in FCs of Lake Victoria in Uganda. Methods: We employed a mixed-methods approach comprising a cross-sectional survey, in-depth interviews, and focus group discussions in 2 FCs. Multivariable logistic regression was used to analyze quantitative data and a thematic approach to generate themes from the qualitative data. Results: Up to 1410 individuals participated in the survey and 47 in the qualitative study. Just over a third (35.6%) used FP. The most commonly used methods were condoms, pills, and injectables. In Kigungu community, participants whose religion was Anglican and Muslim were more likely to use FP than Catholics (adjusted odds ratio [aOR] 1.45; 95% CI 1.05-1.99 and aOR 1.45; 95% CI 1.05-2.07, respectively). Participants were more likely to use FP if they had satisfactory FP knowledge compared to those with no satisfactory FP knowledge (aOR 1.79; 95% CI 1.23-2.61), or if they were married compared to their single counterparts (aOR 1.84; 95% CI 1.32-2.57). In both communities, participants were more likely to use FP if they had 2 or more sexual partners in the past 12 months than those with less than 2 sexual partners (aOR 1.41 95% CI 1.07-1.87 and aOR 2.60; 95% CI 1.36-4.97). Excessive bleeding and delayed fecundity; fertility desire; gender preferences of children; method stock outs and lack of FP trained personnel constituted barriers to FP use. There were also cultural influences in favor of large families. Conclusion: FP use in FCs is suboptimal. Barriers of FP use were mainly biomedical, religious, social, and cultural, which underscores a need for FP education and strengthening of FP service provision in FCs.


Subject(s)
Family Planning Services , HIV Infections , Child , Cross-Sectional Studies , Humans , Lakes , Sexual Partners , Uganda
9.
PLoS One ; 15(5): e0233151, 2020.
Article in English | MEDLINE | ID: mdl-32469893

ABSTRACT

INTRODUCTION: Intramuscular electroporation (IM/EP) is a vaccine delivery technique that improves the immunogenicity of DNA vaccines. We evaluated the acceptability and tolerability of electroporation among healthy African study participants. METHODS: Forty-five participants were administered a DNA vaccine (HIV-MAG) or placebo by electroporation at three visits occurring at four week-intervals. At the end of each visit, participants were asked to rate pain at four times: (1) when the device was placed on the skin and vaccine injected, before the electrical stimulation, (2) at the time of electrical stimulation and muscle contraction, and (3) at 10 minutes and (4) 30 minutes after the procedure was completed. For analyses, pain level was dichotomized as either "acceptable" (none/slight/uncomfortable) or "too much" (Intense, severe, and very severe) and examined over time using repeated measures models. Optional brief comments made by participants were summarized anecdotally. RESULTS: All 45 participants completed all three vaccination visits; none withdrew from the study due to the electroporation procedure. Most (76%) reported pain levels as acceptable at every time point across all vaccination visits. The majority of "unacceptable" pain was reported at the time of electrical stimulation. The majority of the participants (97%) commented that they preferred electroporation to standard injection. CONCLUSION: Repeated intramuscular electroporation for vaccine delivery was found to be acceptable and feasible among healthy African HIV vaccine trial participants. The majority of participants reported an acceptable pain level at all vaccination time points. Further investigation may be warranted into the value of EP to improve immunization outcomes. ClinicalTrials.gov NCT01496989.


Subject(s)
AIDS Vaccines/administration & dosage , Electroporation , Muscle Contraction , Muscle, Skeletal , Vaccination , Vaccines, DNA/administration & dosage , Adolescent , Adult , Double-Blind Method , Female , Humans , Male , Middle Aged
10.
Pan Afr Med J ; 37: 208, 2020.
Article in English | MEDLINE | ID: mdl-33505576

ABSTRACT

INTRODUCTION: fishing communities in Uganda are key populations for HIV, with persistently higher prevalence and incidence than the general population. METHODS: between March and August 2014, a cross sectional survey was conducted in 10 fishing communities of Lake Victoria in Uganda. Data was collected on socio-behavioural characteristics using interviewer administered questionnaires and venous blood collected for HIV testing. Prevalent HIV infections among adolescents and young people aged 13 to 24 years was estimated and the factors associated with those infections determined using multi variable logistic regression modelling. RESULTS: HIV prevalence was 10.8% among the 630 (96.5%) who provided a blood sample. Females were 3.5 times as likely to have HIV infection as males (aOR=3.52, 95% CI: 1.34-9.22). Young people aged 20-24 years were twice as likely to be HIV infected as those aged 13-19 years (aOR=1.77, 95% CI: 0.05-2.10), participants without formal education or those who had studied up to primary level were more likely to be HIV infected than those who had post primary education ((aOR=2.45, 95% CI: 1.19-5.07) or (5.29 (1.35-20.71) respectively). Reporting more than one sexual partner in the past 6 months was associated with HIV prevalent infection than those reporting no sexual partners (aOR=6.44, 95% CI: 1.27-32.83). CONCLUSION: adolescents and young people aged 13-24 years in fishing communities around Lake Victoria, Uganda, have a high HIV prevalence, with females having a three-fold higher level than males. These findings highlight-the need to improve HIV prevention among young females living in these fishing communities.


Subject(s)
HIV Infections/epidemiology , Sexual Behavior/statistics & numerical data , Sexual Partners , Adolescent , Cross-Sectional Studies , Educational Status , Female , Humans , Male , Prevalence , Sex Distribution , Surveys and Questionnaires , Uganda/epidemiology , Young Adult
11.
Trials ; 20(1): 443, 2019 Jul 19.
Article in English | MEDLINE | ID: mdl-31324206

ABSTRACT

BACKGROUND: The foreskin is the main site of HIV acquisition in a heterosexual uncircumcised man, but many men in endemic countries are reluctant to undergo penile circumcision (PC). Observational studies suggest that proinflammatory anaerobic bacteria are enriched on the uncircumcised penis, where they may enhance HIV susceptibility through increased foreskin inflammatory cytokines and the recruitment of HIV-susceptible CD4+ target cells. This trial will examine the impact of systemic and topical antimicrobials on ex vivo foreskin HIV susceptibility. METHODS/DESIGN: This randomized, open-label clinical trial will randomize 125 HIV-negative Ugandan men requesting voluntary PC to one of five arms (n = 25 each). The control group will receive immediate PC, while the four intervention groups will defer PC for 1 month and be provided in the interim with either oral tinidazole, penile topical metronidazole, topical clindamycin, or topical hydrogen peroxide. The impact of these interventions on HIV entry into foreskin-derived CD4+ T cells will be quantified ex vivo at the time of PC using a clade A, R5 tropic HIV pseudovirus assay (primary endpoint); secondary endpoints include the impact of antimicrobials on immune parameters and the microbiota of the participant's penis and of the vagina of their female partner (if applicable), assessed by multiplex enzyme-linked immunosorbent assay and 16S rRNA sequencing. DISCUSSION: There is a critical need to develop acceptable, simple, and effective means of HIV prevention in men unwilling to undergo PC. This trial will provide insight into the causative role of the foreskin microbiota on HIV susceptibility, and the impact of simple microbiota-focused clinical interventions. This may pave the way for future clinical trials using low-cost, nonsurgical intervention(s) to reduce HIV risk in uncircumcised heterosexual men. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03412071 . Retrospectively registered on 26 January 2018.


Subject(s)
Anti-Infective Agents/administration & dosage , Bacteria/drug effects , CD4-Positive T-Lymphocytes/drug effects , Clindamycin/administration & dosage , Foreskin/microbiology , HIV Infections/prevention & control , Hydrogen Peroxide/administration & dosage , Metronidazole/administration & dosage , Tinidazole/administration & dosage , Administration, Cutaneous , Administration, Oral , Anti-Infective Agents/adverse effects , Bacteria/immunology , Bacteria/pathogenicity , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/microbiology , Circumcision, Male , Clindamycin/adverse effects , Female , Foreskin/virology , HIV Infections/immunology , HIV Infections/transmission , HIV Infections/virology , Heterosexuality , Host-Pathogen Interactions , Humans , Hydrogen Peroxide/adverse effects , Male , Metronidazole/adverse effects , Randomized Controlled Trials as Topic , Time Factors , Tinidazole/adverse effects , Treatment Outcome , Uganda
12.
Am J Reprod Immunol ; 82(1): e13143, 2019 07.
Article in English | MEDLINE | ID: mdl-31081958

ABSTRACT

PROBLEM: Biological mechanisms of foreskin HIV acquisition are poorly defined. The inner foreskin is preferentially infected in explant models, so we hypothesized that this site would be enriched for HIV-susceptible CD4+ T cells and proinflammatory/chemoattractant cytokines. METHOD OF STUDY: A total of 42 HIV-uninfected Ugandan men without genital symptoms provided foreskin tissues and swabs at the time of elective penile circumcision. The immune phenotype of foreskin-derived CD4+ T cells and entry of a CCR5-tropic HIV pseudovirus was characterized, and specific cytokine levels assayed by multiplexed chemiluminescent ELISA. RESULTS: Unexpectedly, outer foreskin CD4+ T cells more frequently expressed CCR5 (median 29.2% vs 22.9%, P = 0.01) and CD69 (median 36.5% vs 15%, P < 0.01), and on a per-cell basis, HIV entry was higher. However, overall CD4+ T cell density was approximately twofold higher in the inner foreskin, and several highly susceptible T cell subsets were increased at this site, including Th17 cells (20.0% vs 14.1%, P = 0.0021). Specific pro-inflammatory cytokine levels were also higher on the inner foreskin surface (IL-17, IL-8, RANTES and IL-1ß; all P < 0.05). CONCLUSION: There was marked heterogeneity in CD4+ T cell populations and immune milieu between inner and outer foreskin tissues. Despite higher per-cell viral entry into CD4+ T cells from the outer foreskin, the higher target cell density and enriched pro-inflammatory cytokines of the inner foreskin suggest that this may be a preferential site for HIV acquisition.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Foreskin/immunology , HIV Infections/immunology , T-Lymphocyte Subsets/immunology , Adult , CD4-Positive T-Lymphocytes/virology , Cytokines/immunology , Disease Susceptibility/immunology , HEK293 Cells , Humans , Male , T-Lymphocyte Subsets/virology , Uganda , Young Adult
13.
AIDS Res Hum Retroviruses ; 35(4): 382-387, 2019 04.
Article in English | MEDLINE | ID: mdl-30560683

ABSTRACT

Uganda is among the most HIV/AIDS-afflicted countries, and many HIV-infected persons live in remote areas with poor access to health care. The success of HIV care programs relies in part on patient monitoring using CD4 T cell counts. We conducted an evaluation of the point-of-care PIMA test using BD FACSCount as a gold standard. One hundred fifty-one participants were enrolled, provided venous blood and samples tested at the point of care with the Alere PIMA™ CD4 Analyzer and the BD FACSCount in the UVRI-IAVI main laboratory. Correlation between the methods was assessed, as was the ability of the Pima Analyzer to predict values <200, <350, and ≥500 CD4 cells/mm3 when compared with BD FACSCount as the gold standard. A near-perfect positive Pearson correlation coefficient (r = 0.948; p < .0001) between the two methods was observed. The Alere PIMA Analyzer had a mean bias of -32.5 cells/mm3. The sensitivity and specificity, for PIMA to predict CD4 lymphocyte count less than 200 cells/mm3, were 71.4% and 100%, respectively; less than 350 cells/mm3 were 84.6% and 94.6%, respectively; and at CD4 count less than 500 cells/mm3 were 94.4% and 100%. The Alere Pima Analyzer provides reliable CD4 cell count measurement and is suitable for monitoring and screening eligible HIV patients in hard-to-reach settings.


Subject(s)
CD4 Lymphocyte Count/methods , Counseling , HIV Infections/diagnosis , Mass Screening/methods , Point-of-Care Systems/standards , Adult , CD4 Lymphocyte Count/instrumentation , CD4 Lymphocyte Count/standards , Female , Flow Cytometry , Humans , Lakes , Male , Mass Screening/instrumentation , Mobile Health Units , Rural Population , Sensitivity and Specificity , Uganda
14.
BMC Infect Dis ; 18(1): 591, 2018 Nov 21.
Article in English | MEDLINE | ID: mdl-30463524

ABSTRACT

BACKGROUND: High retention (follow-up) rates improve the validity and statistical power of outcomes in longitudinal studies and the effectiveness of programs with prolonged administration of interventions. We assessed participant retention in a potential HIV vaccine trials population of fishing communities along Lake Victoria, Uganda. METHODS: In a community-based individual randomized trial, 662 participants aged 15-49 years were randomized to either mobile phone or physical contact tracing reminders and followed up at months 1, 2, 3, 6, 12 and 18 post-enrolment. The visit schedules aimed at mimicking a vaccine efficacy trial representing an early interval (months 1-6) where most vaccinations would be administered and a later period of post-vaccination follow-up. The primary outcome was retention measured as the proportion of post-baseline follow up visits completed by a participant. Retention was estimated in early and later follow-up intervals, and overall for all the six follow-up visits. Adjusted differences in retention between the study arms were determined by multivariable logistic regression using Stata® 14. One participant was later dropped from the analysis because of age ineligibility discovered after enrolment. RESULTS: Of the expected total follow up visits of 3966 among 661 participants, 84.1% (3334) were attained; 82.1% (1626/1980) in the phone arm and 86% (1708/1986) in the physical tracing arm (p = 0.001). No statistically significant differences in retention were observed between the study arms in the first 6 months but thereafter, retention was significantly higher for physical contact reminders than mobile phones; 91.5% versus 82.1% (p < 0.0001) at month 12 and 82.8% versus 75.4%, (p = 0.021) at month 18. Controlling for sex, age, education, occupation, community location, length of stay and marital status, the odds of good retention (completing 5 out of 6 follow-up visits) were 1.56 (95% CI;1.08-2.26, p = 0.018) for physical contact tracing compared to mobile phone tracing. Other statistically significant predictors of good retention were residing on islands and having stayed in the fishing communities for 5 or more years. CONCLUSIONS: Among fishing communities of Lake Victoria, Uganda, 84% of follow-up visits can be attained and participant retention is higher using physical contact reminders than mobile phones. TRIAL REGISTRATION NUMBER: PACTR201311000696101 ( http://www.pactr.org/ ). retrospectively registered on 05 November, 2013.


Subject(s)
AIDS Vaccines/therapeutic use , Cell Phone , Contact Tracing/methods , Immunization Programs , Patient Participation , Reminder Systems , Adolescent , Adult , Ambulatory Care/statistics & numerical data , Contact Tracing/statistics & numerical data , Female , Humans , Immunization Programs/methods , Immunization Programs/organization & administration , Lakes , Lost to Follow-Up , Male , Middle Aged , Occupations , Patient Participation/methods , Patient Participation/statistics & numerical data , Physical Examination/methods , Physical Examination/statistics & numerical data , Population Surveillance/methods , Reminder Systems/standards , Retrospective Studies , Telemedicine/methods , Telemedicine/organization & administration , Uganda/epidemiology , Vaccination/statistics & numerical data , Young Adult
15.
BMC Res Notes ; 8: 815, 2015 Dec 24.
Article in English | MEDLINE | ID: mdl-26703879

ABSTRACT

BACKGROUND: Fishing communities are potentially suitable for Human immunodeficiency virus (HIV) efficacy trials due to their high risk profile. However, high mobility and attrition could decrease statistical power to detect the impact of a given intervention. We report dropout and associated factors in a fisher-folk observational cohort in Uganda. METHODS: Human immunodeficiency virus-uninfected high-risk volunteers aged 13-49 years living in five fishing communities around Lake Victoria were enrolled and followed every 6 months for 18 months at clinics located within each community. Volunteers from two of the five communities had their follow-up periods extended to 30 months and were invited to attend clinics 10-40 km (km) away from their communities. Human immunodeficiency virus counseling and testing was provided, and data on sexual behaviour collected at all study visits. Study completion was defined as completion of 18 or 30 months or visits up to the date of sero-conversion and dropout as missing one or more visits. Discrete time survival models were fitted to find factors independently associated with dropout. RESULTS: A total of 1000 volunteers (55% men) were enrolled. Of these, 91.9% completed 6 months, 85.2% completed 12 months and 76.0% completed 18 months of follow-up. In the two communities with additional follow-up, 76.9% completed 30 months. In total 299 (29.9%) volunteers missed at least one visit (dropped out). Dropout was independently associated with age (volunteers aged 13-24 being most likely to dropout), gender [men being more likely to dropout than women [adjusted hazard ratio (aHR) 1.4; 95% confidence interval (CI) 1.1-1.8)], time spent in the fishing community (those who stayed <1 year being most likely to dropout), History of marijuana use (users being more likely to dropout than non-users [1.7; (1.2-2.5)], ethnicity (non-Baganda being more likely to dropout than Baganda [1.5; (1.2-1.9)], dropout varied between the five fishing communities, having a new sexual partner in the previous 3 months [1.3 (1.0-1.7)] and being away from home for ≥2 nights in the month preceding the interview [1.4 (1.1-1.8)]. CONCLUSION: Despite a substantial proportion dropping out, retention was sufficient to suggest that by incorporating retention strategies it will be possible to conduct HIV prevention efficacy trials in this community.


Subject(s)
HIV Infections/prevention & control , Adolescent , Adult , Animals , Cohort Studies , Female , Fishes , Follow-Up Studies , HIV Infections/epidemiology , Humans , Lakes , Male , Middle Aged , Patient Dropouts/statistics & numerical data , Risk-Taking , Sexual Behavior , Uganda/epidemiology , Young Adult
17.
PLoS One ; 10(10): e0141531, 2015.
Article in English | MEDLINE | ID: mdl-26512727

ABSTRACT

INTRODUCTION: Fishing communities (FCs) in Uganda have high HIV infection rates but poor access to health services including family planning (FP). Although FP is a cost-effective public health intervention, there is a paucity of data on knowledge and use of modern FP in FCs. This study determined knowledge and use of modern FP methods in FCs of Uganda. METHODS: Data were accrued from a 12-month follow up of 1,688 HIV-uninfected individuals, 18-49 years from 8 FCs along Lake Victoria, between September 2011 and March 2013. Data on knowledge and use of modern FP were collected through a semi-structured questionnaire. Prevalence Risk Ratios with corresponding 95% CIs were used to determine factors associated with Modern FP knowledge and use. RESULTS: The mean age was 31.4 years, with nearly half (48.8%) being females while more than half (58.6%) had attained up to primary education level. Knowledge of modern FP was high, 87.5% (1477/1688); significantly higher among females [adj. PRR = 4.84 (95% CI; 3.08, 7.61)], among older respondents (25-29 years) [adj. PRR = 1.83 (95% CI; 1.12, 2.99)] compared to younger ones (18-24 years) and among those conducting business [adj. PRR = 2.42(95% CI; 1.02, 5.74)] relative to those primarily in fishing. Just over a third (35.2%, 595/1688) reported use of at least one modern FP method. Use of modern FP methods was significantly higher among females [adj. PRR = 2.04 (95% CI; 1.56, 2.65, and among those reporting multiple sexual partnerships [adj. PRR = 2.12, 95% CI; 1.63, 2.76)]. Nonuse of modern methods was mostly due to desire for more children (30.6%), fear of side effects (12.2%) and partner refusal (5.2%). CONCLUSION: Despite their high knowledge of FP, FCs have low use of modern FP methods. Key barriers to use of modern FP methods were high fertility desires, fear of perceived side effects and partner refusal of methods.


Subject(s)
Family Planning Services/statistics & numerical data , HIV Infections/prevention & control , Rural Population/statistics & numerical data , Adolescent , Adult , Family Planning Services/methods , Female , Fisheries , HIV Infections/epidemiology , Humans , Male , Middle Aged , Uganda
18.
Pan Afr Med J ; 21: 104, 2015.
Article in English | MEDLINE | ID: mdl-26379811

ABSTRACT

INTRODUCTION: Women in fishing communities in Uganda are more at risk and have higher rates of HIV infection. Socio-cultural gender norms, limited access to health information and services, economic disempowerment, sexual abuse and their biological susceptibility make women more at risk of infection. There is need to design interventions that cater for women's vulnerability. We explore factors affecting recruitment and retention of women from fishing communities in HIV prevention research. METHODS: An HIV incidence cohort screened 2074 volunteers (1057 men and 1017 women) aged 13-49 years from 5 fishing communities along Lake Victoria using demographic, medical history, risk behaviour assessment questionnaires.1000 HIV negative high risk volunteers were enrolled and followed every 6 months for 18 months. Factors associated with completion of study visits among women were analyzed using multivariable logistic regression. RESULTS: Women constituted 1,017(49%) of those screened, and 449(45%) of those enrolled with a median (IQR) age of 27 (22-33) years. Main reasons for non-enrolment were HIV infection (33.9%) and reported low risk behaviour (37.5%). A total of 382 (74%) women and 332 (69%) men completed all follow up visits. Older women (>24 yrs) and those unemployed, who had lived in the community for 5 years or more, were more likely to complete all study visits. CONCLUSION: Women had better retention rates than men at 18 months. Strategies for recruiting and retaining younger women and those who have stayed for less than 5 years need to be developed for improved retention of women in fishing communities in HIV prevention and research Programs.


Subject(s)
Biomedical Research/organization & administration , HIV Infections/prevention & control , Patient Selection , Adolescent , Adult , Age Factors , Animals , Female , Fisheries , Follow-Up Studies , HIV Infections/epidemiology , Humans , Logistic Models , Male , Middle Aged , Risk-Taking , Sex Factors , Time Factors , Uganda/epidemiology , Young Adult
19.
PLoS Negl Trop Dis ; 9(9): e0004067, 2015.
Article in English | MEDLINE | ID: mdl-26335139

ABSTRACT

BACKGROUND: Schistosoma mansoni infection has been associated with an increased HIV prevalence in humans and SHIV incidence in primate models. We hypothesized that immune activation from this gastrointestinal mucosa infection would increase highly HIV-susceptible CD4 T cell subsets in the blood and the foreskin through common mucosal homing. METHODOLOGY/PRINCIPAL FINDINGS: Foreskin tissue and blood were obtained from 34 HIV- and malaria-uninfected Ugandan men who volunteered for elective circumcision, 12 of whom were definitively positive for S. mansoni eggs in stool and 12 definitively negative for both S. mansoni eggs and worm antigen. Tissue and blood T cell subsets were characterized by flow cytometry and immunohistochemistry (IHC). Th17 and Th1 cells from both the blood and foreskin expressed higher levels of CCR5 and were more activated than other CD4 T cell subsets. S. mansoni-infected men had a higher frequency of systemic Th1 cells (22.9 vs. 16.5% of blood CD4 T cells, p<0.05), Th17 cells (2.3 vs. 1.5%, p<0.05), and Th22 cells (0.5 vs. 0.3%, p<0.01) than uninfected men. Additionally, Th17 cells in the blood of S. mansoni-infected men demonstrated enhanced function (28.1 vs. 16.3% producing multiple cytokines, p = 0.046). However, these immune alterations were not observed in foreskin tissue. CONCLUSIONS/SIGNIFICANCE: S. mansoni infection was associated with an increased frequency of highly HIV-susceptible Th1, Th17 and Th22 cell subsets in the blood, but these T cell immune differences did not extend to the foreskin. S. mansoni induced changes in T cell immunology mediated through the common mucosal immune system are not likely to increase HIV susceptibility in the foreskin.


Subject(s)
Blood/immunology , Foreskin/immunology , Schistosomiasis mansoni/pathology , T-Lymphocyte Subsets/immunology , Adolescent , Adult , Animals , Cross-Sectional Studies , Disease Susceptibility , Flow Cytometry , HIV Infections/immunology , Humans , Immunohistochemistry , Lymphocyte Activation , Male , Middle Aged , Schistosomiasis mansoni/immunology , Uganda , Young Adult
20.
PLoS One ; 10(8): e0134287, 2015.
Article in English | MEDLINE | ID: mdl-26252526

ABSTRACT

BACKGROUND: Strategies to enhance the immunogenicity of DNA vaccines in humans include i) co-administration of molecular adjuvants, ii) intramuscular administration followed by in vivo electroporation (IM/EP) and/or iii) boosting with a different vaccine. Combining these strategies provided protection of macaques challenged with SIV; this clinical trial was designed to mimic the vaccine regimen in the SIV study. METHODS: Seventy five healthy, HIV-seronegative adults were enrolled into a phase 1, randomized, double-blind, placebo-controlled trial. Multi-antigenic HIV (HIVMAG) plasmid DNA (pDNA) vaccine alone or co-administered with pDNA encoding human Interleukin 12 (IL-12) (GENEVAX IL-12) given by IM/EP using the TriGrid Delivery System was tested in different prime-boost regimens with recombinant Ad35 HIV vaccine given IM. RESULTS: All local reactions but one were mild or moderate. Systemic reactions and unsolicited adverse events including laboratory abnormalities did not differ between vaccine and placebo recipients. No serious adverse events (SAEs) were reported. T cell and antibody response rates after HIVMAG (x3) prime-Ad35 (x1) boost were independent of IL-12, while the magnitude of interferon gamma (IFN-γ) ELISPOT responses was highest after HIVMAG (x3) without IL-12. The quality and phenotype of T cell responses shown by intracellular cytokine staining (ICS) were similar between groups. Inhibition of HIV replication by autologous T cells was demonstrated after HIVMAG (x3) prime and was boosted after Ad35. HIV specific antibodies were detected only after Ad35 boost, although there was a priming effect with 3 doses of HIVMAG with or without IL-12. No anti-IL-12 antibodies were detected. CONCLUSION: The vaccines were safe, well tolerated and moderately immunogenic. Repeated administration IM/EP was well accepted. An adjuvant effect of co-administered plasmid IL-12 was not detected. TRIAL REGISTRATION: ClinicalTrials.gov NCT01496989.


Subject(s)
AIDS Vaccines/adverse effects , DNA, Viral/adverse effects , DNA, Viral/immunology , Electroporation , HIV Infections/immunology , Immunization, Secondary , Interleukin-12/immunology , AIDS Vaccines/immunology , Adenoviridae/metabolism , Adult , CD8-Positive T-Lymphocytes/immunology , Demography , Double-Blind Method , Enzyme-Linked Immunospot Assay , Female , Flow Cytometry , HIV Antibodies/immunology , Humans , Immunity, Cellular , Immunity, Humoral , Immunization , Interferon-gamma/metabolism , Male , Middle Aged , Placebos , Young Adult
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