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1.
N Engl J Med ; 387(26): 2411-2424, 2022 12 29.
Article in English | MEDLINE | ID: mdl-36516078

ABSTRACT

BACKGROUND: Questions remain concerning the rapidity of immune responses and the durability and safety of vaccines used to prevent Zaire Ebola virus disease. METHODS: We conducted two randomized, placebo-controlled trials - one involving adults and one involving children - to evaluate the safety and immune responses of three vaccine regimens against Zaire Ebola virus disease: Ad26.ZEBOV followed by MVA-BN-Filo 56 days later (the Ad26-MVA group), rVSVΔG-ZEBOV-GP followed by placebo 56 days later (the rVSV group), and rVSVΔG-ZEBOV-GP followed by rVSVΔG-ZEBOV-GP 56 days later (the rVSV-booster group). The primary end point was antibody response at 12 months, defined as having both a 12-month antibody concentration of at least 200 enzyme-linked immunosorbent assay units (EU) per milliliter and an increase from baseline in the antibody concentration by at least a factor of 4. RESULTS: A total of 1400 adults and 1401 children underwent randomization. Among both adults and children, the incidence of injection-site reactions and symptoms (e.g., feverishness and headache) was higher in the week after receipt of the primary and second or booster vaccinations than after receipt of placebo but not at later time points. These events were largely low-grade. At month 12, a total of 41% of adults (titer, 401 EU per milliliter) and 78% of children (titer, 828 EU per milliliter) had a response in the Ad26-MVA group; 76% (titer, 992 EU per milliliter) and 87% (titer, 1415 EU per milliliter), respectively, had a response in the rVSV group; 81% (titer, 1037 EU per milliliter) and 93% (titer, 1745 EU per milliliter), respectively, had a response in the rVSV-booster group; and 3% (titer, 93 EU per milliliter) and 4% (titer, 67 EU per milliliter), respectively, had a response in the placebo group (P<0.001 for all comparisons of vaccine with placebo). In both adults and children, antibody responses with vaccine differed from those with placebo beginning on day 14. CONCLUSIONS: No safety concerns were identified in this trial. With all three vaccine regimens, immune responses were seen from day 14 through month 12. (Funded by the National Institutes of Health and others; PREVAC ClinicalTrials.gov number, NCT02876328; EudraCT numbers, 2017-001798-18 and 2017-001798-18/3rd; and Pan African Clinical Trials Registry number, PACTR201712002760250.).


Subject(s)
Ebola Vaccines , Ebolavirus , Hemorrhagic Fever, Ebola , Adult , Child , Humans , Antibodies, Viral , Democratic Republic of the Congo , Ebola Vaccines/therapeutic use , Hemorrhagic Fever, Ebola/prevention & control
2.
Clin Infect Dis ; 78(4): 870-879, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-37967326

ABSTRACT

BACKGROUND: The rVSVΔG-ZEBOV-GP vaccine (ERVEBO®) is a single-dose, live-attenuated, recombinant vesicular stomatitis virus vaccine indicated for the prevention of Ebola virus disease (EVD) caused by Zaire ebolavirus in individuals 12 months of age and older. METHODS: The Partnership for Research on Ebola VACcination (PREVAC) is a multicenter, phase 2, randomized, double-blind, placebo-controlled trial of 3 vaccine strategies in healthy children (ages 1-17) and adults, with projected 5 years of follow-up (NCT02876328). Using validated assays (GP-ELISA and PRNT), we measured antibody responses after 1-dose rVSVΔG-ZEBOV-GP, 2-dose rVSVΔG-ZEBOV-GP (given on Day 0 and Day 56), or placebo. Furthermore, we quantified vaccine virus shedding in a subset of children's saliva using RT-PCR. RESULTS: In total, 819 children and 783 adults were randomized to receive rVSVΔG-ZEBOV-GP (1 or 2 doses) or placebo. A single dose of rVSVΔG-ZEBOV-GP increased antibody responses by Day 28 that were sustained through Month 12. A second dose of rVSVΔG-ZEBOV-GP given on Day 56 transiently boosted antibody concentrations. In vaccinated children, GP-ELISA titers were superior to placebo and non-inferior to vaccinated adults. Vaccine virus shedding was observed in 31.7% of children, peaking by Day 7, with no shedding observed after Day 28 post-dose 1 or any time post-dose 2. CONCLUSIONS: A single dose of rVSVΔG-ZEBOV-GP induced robust antibody responses in children that was non-inferior to the responses induced in vaccinated adults. Vaccine virus shedding in children was time-limited and only observed after the first dose. Overall, these data support the use of rVSVΔG-ZEBOV-GP for the prevention of EVD in at-risk children. Clinical Trials Registration. The study is registered at ClinicalTrials.gov (NCT02876328), the Pan African Clinical Trials Registry (PACTR201712002760250), and the European Clinical Trials Register (EudraCT number: 2017-001798-18).


Subject(s)
Ebola Vaccines , Ebolavirus , Hemorrhagic Fever, Ebola , Adult , Child , Humans , Antibodies, Viral , Viral Envelope Proteins , Vaccines, Synthetic , Vaccination/methods , Vaccines, Attenuated , Immunogenicity, Vaccine
3.
Trop Med Int Health ; 28(3): 237-246, 2023 03.
Article in English | MEDLINE | ID: mdl-36717965

ABSTRACT

OBJECTIVES: This cross-sectional survey aimed to explore associations between age of menarche, early sexual debut and high-risk sexual behaviour among urban Tanzanian schoolgirls. METHODS: Secondary schoolgirls aged 17-18 years from Mwanza, Tanzania, participated in structured face-to-face questionnaire-based interviews, conducted by nurses and clinicians. Age of menarche was evaluated in categories of 11-12, 13-14, 15-16 or ≥17 years. Primary outcome measures were self-reported early sexual debut (first vaginal sex at <16 years) and high-risk sexual behaviour, including non-use of condoms, having sex for gifts/money, having older sexual partners and/or other risky behaviours. RESULTS: Of 401 girls enrolled, 174 (43.4%) reported prior vaginal sex. Prevalence of early sexual debut was 14.2% but pressured/forced sex and risky sexual behaviours were common. Adjusted for potential confounding, younger age at menarche was associated with early sexual debut (adjusted odds ratio for linear trend: 1.88 per category, 95% confidence interval: 1.21-2.92, p = 0.005). This association remained after excluding girls with first sex at <8 years or experiencing pressure or force at first sex. Further, adjusted for potential confounding (including ever experiencing forced sex), early sexual debut was associated with high-risk sexual behaviour (adjusted odds ratio: 2.85, 95% confidence interval: 1.38-5.88, p = 0.004). CONCLUSIONS: Among urban Tanzanian school girls, younger age of menarche was associated with early sexual debut, and early sexual debut was associated with high-risk sexual behaviour. Researchers and public health professionals developing and delivering interventions aimed at preventing adverse sexual health outcomes should consider the impact of these early biological and sexual exposures.


Subject(s)
Menarche , Sexual Behavior , Female , Humans , Cross-Sectional Studies , Tanzania/epidemiology , Sexual Partners
4.
Arch Sex Behav ; 52(1): 161-175, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36123563

ABSTRACT

Although heterosexual oral and anal sexual behaviors have been reported in sub-Saharan Africa, little is known about how they are understood and perceived, particularly, in West Africa. We undertook a qualitative exploration of local terminologies and sexual scripts associated with heterosexual oral and anal sex in preparation for a quantitative survey. We held focus group discussions (18) and interviews (44) with younger and middle-aged men and women from the general population and female sex workers (FSWs) in selected communities in Ibadan. Most participants had heard of oral and anal sex. Younger adults aged 18-25 years, particularly male participants and FSWs, appeared more informed than older adults in the general population. Sexually explicit movies were the most cited source of information. Oral and anal sexual behaviors were considered sensitive, with different local names, meanings, and interpretations. Participants advised against the use of slang terms in research. We identified six different scripts employed by participants in discussing oral and anal sex practices: protecting sexual relationship, financial reward, an alternative to vaginal sex, pleasure, male dominance and control, and risk, stigma, and disgust.


Subject(s)
HIV Infections , Sex Workers , Middle Aged , Female , Humans , Male , Aged , Adolescent , Young Adult , Adult , Heterosexuality , Nigeria , Sexual Behavior , Attitude , Condoms
5.
Emerg Infect Dis ; 28(3): 734-738, 2022 03.
Article in English | MEDLINE | ID: mdl-35202536

ABSTRACT

We explored the association of Ebola virus antibody seropositivity and concentration with potential risk factors for infection. Among 1,282 adults and children from a community affected by the 2014-2016 Ebola outbreak in Sierra Leone, 8% were seropositive for virus antibodies but never experienced disease symptoms. Antibody concentration increased with age.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Adult , Child , Disease Outbreaks , Glycoproteins , Hemorrhagic Fever, Ebola/epidemiology , Humans , Immunoglobulin G , Seroepidemiologic Studies , Sierra Leone/epidemiology
6.
Trop Med Int Health ; 26(11): 1345-1355, 2021 11.
Article in English | MEDLINE | ID: mdl-34310816

ABSTRACT

Cervical cancer is the leading cause of cancer-related morbidity and mortality in many sub-Saharan African (SSA) countries, including Tanzania. Most cervical cancer cases worldwide are attributable to infection of the cervix with Human Papillomavirus (HPV), a vaccine-preventable sexually transmitted infection (STI). Over the past 10 years, we have conducted a programme of HPV research in pre-adolescents and adolescents in Mwanza, the second-largest city in Tanzania, which is situated in a malaria-endemic region. In this narrative review article, we summarise the contribution of our work, alongside work of others, to improve the understanding of HPV epidemiology in SSA and development of setting-appropriate, evidence-based intervention strategies. We present evidence for very high prevalence and incidence of HPV infection among female SSA adolescents around the time of sexual debut, describe risk factors for HPV acquisition, and discuss associations between HPV, HIV and other STIs, which are also highly prevalent within this population. We summarise findings from early clinical trials of HPV vaccines in SSA, the first of which was an immunogenicity and safety trial conducted in Mwanza, Tanzania, and Dakar, Senegal. Within the trial, we evaluated for the first time the potential impact of malaria and helminth infection on vaccine-induced antibody responses in Tanzanian girls. We describe research evaluating optimal HPV vaccine delivery strategies within this setting, perceived requirements for and barriers to vaccine implementation among key informants from LMIC, vaccine acceptability among girls and parents, and opportunities for co-delivery of interventions alongside HPV vaccination to an adolescent population. Finally, we discuss country-level barriers to vaccine uptake in LMIC, and ongoing studies in Tanzania and other SSA countries of reduced-dose HPV vaccination schedules that may alleviate cost and logistical barriers to vaccine implementation.


Subject(s)
Adolescent Health , Papillomavirus Infections/prevention & control , Papillomavirus Vaccines/administration & dosage , Uterine Cervical Neoplasms/prevention & control , Vaccination/trends , Adolescent , Female , Humans , Papillomavirus Infections/epidemiology , Sexual Behavior , Tanzania/epidemiology , Uterine Cervical Neoplasms/epidemiology
7.
Emerg Infect Dis ; 26(11): 2713-2716, 2020 11.
Article in English | MEDLINE | ID: mdl-32946370

ABSTRACT

Four persons with severe acute respiratory syndrome coronavirus 2 infection had traveled on the same flight from Boston, Massachusetts, USA, to Hong Kong, China. Their virus genetic sequences are identical, unique, and belong to a clade not previously identified in Hong Kong, which strongly suggests that the virus can be transmitted during air travel.


Subject(s)
Air Travel , Betacoronavirus , Coronavirus Infections/transmission , Disease Transmission, Infectious/statistics & numerical data , Pneumonia, Viral/transmission , Travel-Related Illness , Adult , Aged , Boston/epidemiology , COVID-19 , Coronavirus Infections/epidemiology , Female , Hong Kong/epidemiology , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2
8.
Sex Transm Infect ; 96(3): 211-219, 2020 05.
Article in English | MEDLINE | ID: mdl-31221744

ABSTRACT

OBJECTIVES: Cervical cancer is the leading cause of cancer-related mortality among women in sub-Saharan Africa (SSA). Data on human papillomavirus (HPV) epidemiology in adolescent girls in SSA are essential to inform HPV vaccine policy recommendations for cervical cancer prevention. We assessed the burden of HPV infection, and risk factors for infection, among adolescent girls around the time of sexual debut. METHODS: Cross-sectional study of secondary school girls aged 17-18 years in Tanzania. Consenting participants provided samples for HPV and STI testing. Vaginal swabs were tested for 37 HPV genotypes by Roche Linear Array. Logistic regression was used to identify factors associated with HPV infection. Y chromosome was tested as a marker of recent condomless sex. RESULTS: 163/385 girls (42.3%) reported previous penetrative sex. HPV was detected in 125/385 (32.5%) girls, including 84/163 (51.5%) girls reporting previous sex and 41/222 (18.5%) reporting no previous sex. High-risk (HR) genotypes were detected in 70/125 (56.0%) girls with HPV infection. The most common HR genotype was HPV-16 (15/385; 3.9%). The prevalence of other HR HPV vaccine genotypes was between 0.8% and 3.1%. Among 186 girls who reported no previous sex, were negative for Y chromosome, and had no STI, 32 (17%) had detectable HPV. Lactobacillus sp and bacterial vaginosis-associated bacteria were negatively and positively associated, respectively, with HPV. CONCLUSIONS: HPV prevalence among adolescent girls around the time of sexual debut was high. However, prevalence of most vaccine genotypes was low, indicating that extending the age range of HPV vaccination in this region may be cost-effective.


Subject(s)
Genotype , Papillomaviridae/classification , Papillomaviridae/isolation & purification , Papillomavirus Infections/epidemiology , Adolescent , Cross-Sectional Studies , Female , Humans , Papillomaviridae/genetics , Prevalence , Risk Factors , Tanzania/epidemiology , Time Factors
9.
J Infect Dis ; 220(1): 46-56, 2019 06 05.
Article in English | MEDLINE | ID: mdl-30796818

ABSTRACT

BACKGROUND: Ebola vaccine development was accelerated in response to the 2014 Ebola virus infection outbreak. This phase 1 study (VAC52150EBL1004) assessed safety, tolerability, and immunogenicity of heterologous 2-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimens in the Lake Victoria Basin of Tanzania and Uganda in mid-level altitude, malaria-endemic settings. METHODS: Healthy volunteers aged 18-50 years from Tanzania (n = 25) and Uganda (n = 47) were randomized to receive placebo or active vaccination with Ad26.ZEBOV or MVA-BN-Filo (first vaccination), followed by MVA-BN-Filo or Ad26.ZEBOV (second vaccination) dose 2, respectively, with intervals of 28 or 56 days. RESULTS: Seventy-two adults were randomized to receive vaccine (n = 60) or placebo (n = 12). No vaccine-related serious adverse events were reported. The most frequent solicited local and systemic adverse events were injection site pain (frequency, 70%, 66%, and 42% per dose for MVA-BN-Filo, Ad26.ZEBOV, and placebo, respectively) and headache (57%, 56%, and 46%, respectively). Adverse event patterns were similar among regimens. Twenty-one days after dose 2, 100% of volunteers demonstrated binding antibody responses against Ebola virus glycoprotein, and 87%-100% demonstrated neutralizing antibody responses. Ad26.ZEBOV dose 1 vaccination induced more-robust initial binding antibody and cellular responses than MVA-BN-Filo dose 1 vaccination. CONCLUSIONS: Heterologous 2-dose vaccination with Ad26.ZEBOV and MVA-BN-Filo against Ebola virus is well tolerated and immunogenic in healthy volunteers. CLINICAL TRIALS REGISTRATION: NCT02376400.


Subject(s)
Antibody Formation/immunology , Ebola Vaccines/adverse effects , Ebola Vaccines/immunology , Ebolavirus/immunology , Hemorrhagic Fever, Ebola/immunology , Viral Vaccines/immunology , Adolescent , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Disease Outbreaks/prevention & control , Female , Healthy Volunteers , Hemorrhagic Fever, Ebola/virology , Humans , Male , Middle Aged , Tanzania , Uganda , Vaccination/adverse effects , Vaccines, DNA , Viral Vaccines/adverse effects , Young Adult
10.
Sex Transm Infect ; 95(5): 374-379, 2019 08.
Article in English | MEDLINE | ID: mdl-30636707

ABSTRACT

OBJECTIVE: Human papillomavirus (HPV) DNA has been detected in vaginal samples from adolescent girls who report no previous sex and, in high-income settings, from fingertips, raising the possibility of non-sexual transmission. No such studies originate from East Africa which bears among the highest cervical cancer incidence and HPV prevalence worldwide. HPV-related oral cancer incidence is increasing, but oral HPV prevalence data from East Africa are limited. We aimed to describe the HPV DNA prevalence in genital and non-genital sites and in the bathroom of unvaccinated adolescent girls, and examine genotype concordance between sites. METHODS: We nested a cross-sectional study of HPV in genital and extragenital sites within a cohort study of vaginal HPV acquisition. Unvaccinated girls age 16-18 years in Tanzania, who reported ever having had sex, were consented, enrolled and tested for the presence of HPV DNA in vaginal samples collected using self-administered swabs, oral samples collected using an oral rinse, and on fingertips and bathroom surfaces collected using a cytobrush. RESULTS: Overall, 65 girls were enrolled and 23 (35%, 95% CI 23% to 47%) had detectable vaginal HPV. Adequate (ß-globin positive) samples were collected from 36 girls' fingertips and HPV was detected in 7 (19%, 95% CI 6% to 33%). 63 girls provided adequate oral samples, 4 (6%, 95% CI 0% to 13%) of which had HPV DNA detected. In bathroom samples from 58 girls, 4 (7%, 95% CI 0% to 14%) had detectable HPV DNA. Of the 11 girls with extragenital HPV, six had the same genotype in >1 site. CONCLUSION: We found a high prevalence of HPV in non-genital sites in adolescent girls and in their bathrooms, in this region with a high cervical cancer incidence. Concordance of genotypes between sites supports the possibility of autoinoculation.


Subject(s)
DNA, Viral/genetics , Fingers/virology , Mouth/virology , Papillomaviridae/genetics , Papillomavirus Infections/virology , Adolescent , Cross-Sectional Studies , Female , Humans , Papillomaviridae/classification , Papillomaviridae/isolation & purification , Papillomavirus Infections/diagnosis , Prevalence , Tanzania , Toilet Facilities , Vagina/virology
11.
Sex Transm Infect ; 95(3): 219-227, 2019 05.
Article in English | MEDLINE | ID: mdl-30518620

ABSTRACT

OBJECTIVES: Bacterial vaginosis (BV) increases women's susceptibility to sexually transmitted infections (STIs) and HIV and may partly explain the high incidence of STI/HIV among girls and young women in East and southern Africa. The objectives of this study were to investigate the association between BV and sexual debut, to investigate other potential risk factors of BV and to estimate associations between BV and STIs. METHODS: Secondary school girls in Mwanza, aged 17 and 18 years, were invited to join a cross-sectional study. Consenting participants were interviewed and samples were obtained for STI and BV testing. Factors associated with prevalent BV were analysed using multivariable logistic regression. Y-chromosome was tested as a biomarker for unprotected penile-vaginal sex. RESULTS: Of the 386 girls who were enrolled, 163 (42%) reported having ever had penile-vaginal sex. Ninety-five (25%) girls had BV. The prevalence of BV was 33% and 19% among girls who reported or did not report having ever had penile-vaginal sex, respectively. BV was weakly associated with having ever had one sex partner (adjusted odds ratio (aOR) 1.59;95% CI 0.93 to 2.71) and strongly associated with two or more partners (aOR = 3.67; 95% CI 1.75 to 7.72), receptive oral sex (aOR 6.38; 95% CI 1.22 to 33.4) and having prevalent human papillomavirus infection (aOR = 1.73; 95% CI 1.02 to 2.95). Of the 223 girls who reported no penile-vaginal sex, 12 (5%) tested positive for an STI and 7 (3%) tested positive for Y-chromosome. Reclassifying these positive participants as having ever had sex did not change the key results. CONCLUSIONS: Tanzanian girls attending school had a high prevalence of BV. Increasing number of sex partner was associated with BV; however, 19% of girls who reported no penile-vaginal sex had BV. This suggests that penile-vaginal sexual exposure may not be a prerequisite for BV. There was evidence of under-reporting of sexual debut.


Subject(s)
Papillomavirus Infections/epidemiology , Sexual Behavior , Students , Vaginosis, Bacterial/epidemiology , Adolescent , Cross-Sectional Studies , Female , Humans , Incidence , Papillomavirus Infections/etiology , Prevalence , Reproductive Health , Risk Factors , Tanzania/epidemiology , Vaginosis, Bacterial/etiology
12.
Reprod Health ; 16(1): 48, 2019 May 06.
Article in English | MEDLINE | ID: mdl-31060573

ABSTRACT

BACKGROUND: Oral and anal sexual behaviours are increasingly reported among adolescents and adults reporting heterosexual sex in peer-reviewed journals in high income countries, but less is known about these behaviours in low and middle-income countries, especially in sub-Saharan Africa. The aim of this systematic review is to describe the prevalence of, and motivations for, oral and anal sex among adolescents and adults reporting heterosexual sex in sub-Saharan Africa. METHODS: A systematic review of published articles that reported oral and or anal sex in sub-Saharan Africa was conducted from seven databases up to and including 30th August 2018. RESULTS: Of 13,592 articles, 103 met the inclusion criteria. The prevalence of reporting ever practising oral sex among adolescents, university students and a combined population of adolescents/adults ranged from 1.7-26.6%, 5.0-46.4% and 3.0-47.2% respectively. Similarly, prevalences of reported ever practising anal sex ranged from 6.4-12.4% among adolescents, 0.3-46.5% among university students and 4.3-37.8% amongst combined population of adolescents and adults. Higher prevalences of oral and anal sex were reported among populations at high-risk for sexually transmitted infections and HIV and university students and, in most studies, both behaviours were more commonly reported by males than females. Heterosexual oral and anal sexual acts were associated with some high-risk behaviours such as inconsistent condom use and multiple sexual partners. CONCLUSION: Reported oral and anal sex between men and women are prevalent behaviours in sub-Saharan Africa. Health professionals and policy makers should be aware of these behaviours and their potential associated health risks.


Subject(s)
Sexual Behavior/statistics & numerical data , Adolescent , Adult , Africa South of the Sahara , Humans
13.
PLoS Med ; 15(2): e1002511, 2018 02.
Article in English | MEDLINE | ID: mdl-29485986

ABSTRACT

BACKGROUND: Estimates of sexually transmitted infection (STI) prevalence are essential for efforts to prevent and control STIs. Few large STI prevalence studies exist, especially for low- and middle-income countries (LMICs). Our primary objective was to estimate the prevalence of chlamydia, gonorrhea, trichomoniasis, syphilis, herpes simplex virus type 2 (HSV-2), and bacterial vaginosis (BV) among women in sub-Saharan Africa by age, region, and population type. METHODS AND FINDINGS: We analyzed individual-level data from 18 HIV prevention studies (cohort studies and randomized controlled trials; conducted during 1993-2011), representing >37,000 women, that tested participants for ≥1 selected STIs or BV at baseline. We used a 2-stage meta-analysis to combine data. After calculating the proportion of participants with each infection and standard error by study, we used a random-effects model to obtain a summary mean prevalence of each infection and 95% confidence interval (CI) across ages, regions, and population types. Despite substantial study heterogeneity for some STIs/populations, several patterns emerged. Across the three primary region/population groups (South Africa community-based, Southern/Eastern Africa community-based, and Eastern Africa higher-risk), prevalence was higher among 15-24-year-old than 25-49-year-old women for all STIs except HSV-2. In general, higher-risk populations had greater prevalence of gonorrhea and syphilis than clinic/community-based populations. For chlamydia, prevalence among 15-24-year-olds was 10.3% (95% CI: 7.4%, 14.1%; I2 = 75.7%) among women specifically recruited from higher-risk settings for HIV in Eastern Africa and was 15.1% (95% CI: 12.7%, 17.8%; I2 = 82.3%) in South African clinic/community-based populations. Among clinic/community-based populations, prevalence was generally greater in South Africa than in Southern/Eastern Africa for most STIs; for gonorrhea, prevalence among 15-24-year-olds was 4.6% (95% CI: 3.3%, 6.4%; I2 = 82.8%) in South Africa and was 1.7% (95% CI: 1.2%, 2.6%; I2 = 55.2%) in Southern/Eastern Africa. Across the three primary region/population groups, HSV-2 and BV prevalence was high among 25-49-year-olds (ranging from 70% to 83% and 33% to 44%, respectively). The main study limitation is that the data are not from random samples of the target populations. CONCLUSIONS: Combining data from 18 HIV prevention studies, our findings highlight important features of STI/BV epidemiology among sub-Saharan African women. This methodology can be used where routine STI surveillance is limited and offers a new approach to obtaining critical information on STI and BV prevalence in LMICs.


Subject(s)
HIV Infections/prevention & control , Sexually Transmitted Diseases/epidemiology , Vaginosis, Bacterial/epidemiology , Adolescent , Adult , Africa South of the Sahara/epidemiology , Female , HIV , HIV Infections/epidemiology , Health Promotion/methods , Health Promotion/organization & administration , Health Promotion/standards , Humans , Middle Aged , Prevalence , Young Adult
15.
Clin Trials ; 15(5): 436-443, 2018 10.
Article in English | MEDLINE | ID: mdl-29895178

ABSTRACT

Background/aims During the 2014-2016 West African Ebola epidemic, clinical trials were fast-tracked in order to identify prophylactic vaccines and experimental treatments that might be useful in preventing or treating Ebola. These trials included the ongoing EBOVAC-Salone study, which was established and implemented in Sierra Leone to assess the safety and immunogenicity of the Ad26.ZEBOV/MVA-BN-Filo prime-boost Ebola vaccine regimen. Methods This article describes the experiences of the EBOVAC-Salone research team in setting up and implementing the trial, and provides recommendations for research teams aiming to conduct clinical trials in future outbreak situations. Results Establishing a clinical trial during an outbreak brought some unique challenges, including those related to trial design and the regulatory environment, operational issues, and community engagement. The situation was further complicated by the weak infrastructure and limited experience of clinical trials in Sierra Leone. However, operating in an outbreak context also brought some benefits to the research team, including strong stakeholder support. The EBOVAC-Salone study recruited participants both during and after the outbreak, leading to additional challenges to trial implementation during the post-outbreak transition. Conclusion Many lessons have been learned about setting up and implementing a clinical trial during a devastating Ebola epidemic, and some of the experiences of the EBOVAC-Salone team were mirrored by those of other researchers operating in the region. Common to several of these research groups is a recommendation that research should be more closely incorporated into outbreak response planning, which could expedite the establishment of timely and appropriate research projects. We recommend that the lessons learned by researchers during the West African Ebola epidemic are built into programmes and strategies to improve the responses to future epidemics, wherever they occur.


Subject(s)
Clinical Trials as Topic , Ebola Vaccines/immunology , Adult , Epidemics/prevention & control , Female , Hemorrhagic Fever, Ebola/epidemiology , Humans , Male , Patient Selection , Sierra Leone/epidemiology
16.
BMC Health Serv Res ; 18(1): 173, 2018 03 12.
Article in English | MEDLINE | ID: mdl-29530042

ABSTRACT

BACKGROUND: The burden of cervical cancer and shortage of screening services in Tanzania confers an urgent need for human papillomavirus (HPV) vaccination. However, the sustainability and impact of another new vaccine campaign in an under-resourced health system requires consideration. We aimed to determine the impact of the government's school-based HPV vaccine campaign in Kilimanjaro region on the provision of routine primary health services and staff workload. METHODS: Data on daily numbers of consultations were collected from health facility register books in 63 dispensaries and health centres in North-West Tanzania for 20 weeks in 2014. Changes in outpatient, antenatal care (ANC), family planning (FP) and immunisation service activity levels before, during and after the two HPV vaccination campaigns in 2014 in 30 facilities within Kilimanjaro region ('intervention facilities') were compared with changes in activity levels in 33 facilities in Arusha region ('controls'). Qualitative interviews were conducted with health workers in Kilimanjaro region who delivered HPV vaccination and those who remained at the facility during in-school HPV vaccine delivery to explore perceptions of workload and capacity. RESULTS: Health facility activity levels were low and very variable in both regions. Controlling for district, facility type, catchment population, clinical staff per 1000 catchment population and the timing of other campaigns, no evidence of a decrease in consultations at the health facility during HPV vaccination week was found across outpatient, ANC, routine immunisation and FP services. However, compared to the average week before and after the campaign, health workers reported longer working hours and patient waiting times, feeling over-stretched and performing duties outside their normal roles whilst colleagues were absent from the facility conducting the HPV vaccine campaign. CONCLUSION: Qualitative interviews with health workers revealed that staff absence from the health facility is common for a number of reasons, including vaccination campaigns. Health workers perceived that the absence of their colleagues increased the workload at the health facility. The numbers of consultations for each service on 'normal days' were low and highly variable and there was no clear detrimental effect of the HPV vaccination campaign on routine health service activity.


Subject(s)
Attitude of Health Personnel , Health Personnel/psychology , Immunization Programs , Papillomavirus Vaccines/administration & dosage , Primary Health Care/organization & administration , Workload/psychology , Adolescent , Child , Female , Government Programs , Health Personnel/statistics & numerical data , Health Resources/supply & distribution , Health Services Research , Humans , Qualitative Research , Retrospective Studies , School Health Services , Tanzania , Uterine Cervical Neoplasms/prevention & control
17.
J Infect Dis ; 214(1): 87-95, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-26951818

ABSTRACT

OBJECTIVE: This study was performed to analyze the associations between cervical human papillomavirus (HPV) infection and human immunodeficiency virus (HIV) acquisition, using cervical samples from previous studies in Tanzania and Uganda. METHODS: A total of 161 adult women who acquired HIV infection during follow-up and 464 individually matched HIV-seronegative controls were selected from 5 cohorts of women working in bars and recreational facilities. Stored cervical samples were tested for 37 HPV genotypes, using a polymerase chain reaction assay (Roche Linear Array genotyping assay). Multivariate matched analysis using conditional logistic regression was performed to evaluate HPV infection, persistence, and clearance as predictors of HIV acquisition. RESULTS: HIV seroconverters were significantly more likely than controls to frequently drink alcohol and to be infected with Chlamydia trachomatis, Neisseria gonorrhoeae, or herpes simplex virus type 2. There was no evidence of an association between HIV acquisition and any detectable HPV at the visit prior to HIV seroconversion (adjusted odds ratio, 1.02; 95% confidence interval, .66-1.57) or between HIV acquisition and persistent HPV infection (defined as 2 positive HPV genotype-specific test results at least 6 months apart), cleared HPV infection (defined as a positive HPV test result followed by negative HPV genotype-specific test result), or newly acquired HPV infection, compared with HPV-negative women. CONCLUSIONS: There was no evidence of association between HPV infection status and subsequent HIV acquisition. These results stand in contrast to other observational studies.


Subject(s)
HIV Infections/etiology , Papillomavirus Infections/complications , Uterine Cervical Neoplasms/complications , Adolescent , Adult , Case-Control Studies , Cohort Studies , Female , Humans , Middle Aged , Papillomavirus Infections/genetics , Risk Factors , Tanzania , Uganda , Uterine Cervical Neoplasms/genetics , Young Adult
18.
BMC Public Health ; 16(1): 834, 2016 08 19.
Article in English | MEDLINE | ID: mdl-27543037

ABSTRACT

BACKGROUND: Social mobilisation during new vaccine introductions encourages acceptance, uptake and adherence to multi-dose schedules. Effective communication is considered especially important for human papillomavirus (HPV) vaccine, which targets girls of an often-novel age group. This study synthesised experiences and lessons learnt around social mobilisation, consent, and acceptability during 55 HPV vaccine demonstration projects and 8 national programmes in 37 low and middle-income countries (LMICs) between January 2007 and January 2015. METHODS: A qualitative study design included: (i) a systematic review, in which 1,301 abstracts from five databases were screened and 41 publications included; (ii) soliciting 124 unpublished documents from governments and partner institutions; and (iii) conducting 27 key informant interviews. Data were extracted and analysed thematically. Additionally, first-dose coverage rates were categorised as above 90 %, 90-70 %, and below 70 %, and cross-tabulated with mobilisation timing, message content, materials and methods of delivery, and consent procedures. RESULTS: All but one delivery experience achieved over 70 % first-dose coverage; 60 % achieved over 90 %. Key informants emphasized the benefits of starting social mobilisation early and actively addressing rumours as they emerged. Interactive communication with parents appeared to achieve higher first-dose coverage than non-interactive messaging. Written parental consent (i.e., opt-in), though frequently used, resulted in lower reported coverage than implied consent (i.e., opt-out). Protection against cervical cancer was the primary reason for vaccine acceptability, whereas fear of adverse effects, exposure to rumours, lack of project/programme awareness, and schoolgirl absenteeism were major reasons for non-vaccination. CONCLUSIONS: Despite some challenges in obtaining parental consent and addressing rumours, experiences indicated effective social mobilisation and high HPV vaccine acceptability in LMICs. Social mobilisation, consent, and acceptability lessons were consistent across world regions and HPV vaccination projects/programmes. These can be used to guide HPV vaccination communication strategies without additional formative research.


Subject(s)
Communication , Developing Countries , Papillomavirus Infections/prevention & control , Patient Acceptance of Health Care , Social Environment , Uterine Cervical Neoplasms/prevention & control , Vaccination , Adolescent , Awareness , Child , Female , Government Programs , Humans , Male , Papillomavirus Infections/virology , Papillomavirus Vaccines , Parents , Program Evaluation , Qualitative Research , Uterine Cervical Neoplasms/virology
19.
BMC Public Health ; 16(1): 1140, 2016 11 08.
Article in English | MEDLINE | ID: mdl-27821112

ABSTRACT

BACKGROUND: This paper discusses the establishment of a clinical trial of an Ebola vaccine candidate in Kambia District, Northern Sierra Leone during the epidemic, and analyses the role of social science research in ensuring that lessons from the socio-political context, the recent experience of the Ebola outbreak, and learning from previous clinical trials were incorporated in the development of community engagement strategies. The paper aims to provide a case study of an integrated social science and communications system in the start-up phase of the clinical trial. METHODS: The paper is based on qualitative research methods including ethnographic observation, interviews with trial participants and key stakeholder interviews. RESULTS: Through the case study of EBOVAC Salone, the paper suggests ways in which research can be used to inform communication strategies before and during the setting up of the trial. It explores notions of power, fairness and trust emerging from analysis of the Sierra Leonean context and through ethnographic research, to reflect on three situations in which social scientists and community liaison officers worked together to ensure successful community engagement. Firstly, a section on "power" considers the pitfalls of considering communities as homogeneous and shows the importance of understanding intra-community power dynamics when engaging communities. Secondly, a section on "fairness" shows how local understandings of what is fair can help inform the design of volunteer recruitment strategies. Finally, a section on "trust" highlights how historically rooted rumours can be effectively addressed through active dialogue rather than through an approach focused on correcting misinformation. CONCLUSION: The paper firstly emphasises the value of social science in the setting up of clinical trials, in terms of providing an in depth understanding of context and social dynamics. Secondly, the paper suggests the importance of a close collaboration between research and community engagement to effectively confront political and social dynamics, especially in the context of an epidemic.


Subject(s)
Anthropology , Biomedical Research , Communication , Community-Based Participatory Research , Ebola Vaccines , Hemorrhagic Fever, Ebola/prevention & control , Residence Characteristics , Anthropology, Cultural , Comprehension , Cooperative Behavior , Disease Outbreaks/prevention & control , Epidemics , Hemorrhagic Fever, Ebola/epidemiology , Humans , Power, Psychological , Qualitative Research , Sierra Leone/epidemiology , Social Justice , Trust
20.
PLoS Med ; 12(1): e1001778, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25612136

ABSTRACT

BACKGROUND: Observational studies of a putative association between hormonal contraception (HC) and HIV acquisition have produced conflicting results. We conducted an individual participant data (IPD) meta-analysis of studies from sub-Saharan Africa to compare the incidence of HIV infection in women using combined oral contraceptives (COCs) or the injectable progestins depot-medroxyprogesterone acetate (DMPA) or norethisterone enanthate (NET-EN) with women not using HC. METHODS AND FINDINGS: Eligible studies measured HC exposure and incident HIV infection prospectively using standardized measures, enrolled women aged 15-49 y, recorded ≥15 incident HIV infections, and measured prespecified covariates. Our primary analysis estimated the adjusted hazard ratio (aHR) using two-stage random effects meta-analysis, controlling for region, marital status, age, number of sex partners, and condom use. We included 18 studies, including 37,124 women (43,613 woman-years) and 1,830 incident HIV infections. Relative to no HC use, the aHR for HIV acquisition was 1.50 (95% CI 1.24-1.83) for DMPA use, 1.24 (95% CI 0.84-1.82) for NET-EN use, and 1.03 (95% CI 0.88-1.20) for COC use. Between-study heterogeneity was mild (I(2) < 50%). DMPA use was associated with increased HIV acquisition compared with COC use (aHR 1.43, 95% CI 1.23-1.67) and NET-EN use (aHR 1.32, 95% CI 1.08-1.61). Effect estimates were attenuated for studies at lower risk of methodological bias (compared with no HC use, aHR for DMPA use 1.22, 95% CI 0.99-1.50; for NET-EN use 0.67, 95% CI 0.47-0.96; and for COC use 0.91, 95% CI 0.73-1.41) compared to those at higher risk of bias (p(interaction) = 0.003). Neither age nor herpes simplex virus type 2 infection status modified the HC-HIV relationship. CONCLUSIONS: This IPD meta-analysis found no evidence that COC or NET-EN use increases women's risk of HIV but adds to the evidence that DMPA may increase HIV risk, underscoring the need for additional safe and effective contraceptive options for women at high HIV risk. A randomized controlled trial would provide more definitive evidence about the effects of hormonal contraception, particularly DMPA, on HIV risk.


Subject(s)
Contraceptive Agents, Female/administration & dosage , HIV Infections/epidemiology , Medroxyprogesterone Acetate/administration & dosage , Norethindrone/analogs & derivatives , Adolescent , Adult , Africa South of the Sahara/epidemiology , Contraceptive Agents, Female/adverse effects , Female , HIV Infections/prevention & control , HIV Infections/transmission , Humans , Incidence , Medroxyprogesterone Acetate/adverse effects , Middle Aged , Norethindrone/administration & dosage , Norethindrone/adverse effects , Risk Factors
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