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1.
Vaccine ; 38(24): 4050-4056, 2020 05 19.
Article in English | MEDLINE | ID: mdl-32284269

ABSTRACT

The 2014-2015 outbreak of Ebola Virus Disease (EVD) in West Africa was unprecedented in size and scope. The World Health Organization, government of Guinea and other partners undertook a field trial of efficacy of an Ebola vaccine in Guinea, with a parallel immunogenicity study in front-line workers. However, several obstacles had to be overcome. One was the need to teach Good Clinical Practices to a large group of field workers who had never participated in vaccine clinical trial research. Because the trial design was complex, performing this efficacy trial during an Ebola outbreak would have been challenging even for experienced investigators. For field workers who had never previously participated in a clinical trial, this constituted a daunting challenge. Another challenge was to provide independent monitoring to document the quality and validity of the field trial data to support future regulatory agency licensure. Here we discuss how these challenges were overcome, and what lessons can be drawn for the future. Intensive GCP was expeditiously arranged for 251 clinical study staff on-site in Guinea. The trials were initiated within days after completion of training. Monitoring (100% of participants in the efficacy trial and 50% in the immunogenicity trial) began at the onset of the trials. Early monitoring detected many minor errors but prompt feedback and guidance from the monitors, who explained the mistakes and proposed corrective actions, diminished error frequency as the trials progressed. Monitoring later in the trials showed what one would expect in a study conducted by experienced investigators. Should a vaccine field trial have to be hastily arranged during a future emerging disease outbreak in a developing country setting, our methods of training and monitoring could provide a model.


Subject(s)
Clinical Trials as Topic/standards , Ebola Vaccines/immunology , Health Personnel/education , Hemorrhagic Fever, Ebola , Immunogenicity, Vaccine , Disease Outbreaks/prevention & control , Guinea/epidemiology , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , Humans , Public Health , Research Design , Research Personnel , World Health Organization
2.
BMC Womens Health ; 13: 4, 2013 Feb 06.
Article in English | MEDLINE | ID: mdl-23388094

ABSTRACT

BACKGROUND: The burden of cervical cancer is disproportionately high in low-resource settings. With limited implementation of human papillomavirus (HPV) vaccines on the horizon in the developing world, reliable data on the epidemiology of high-risk HPV (HR-HPV) infection in distinct geographic populations is essential to planners of vaccination programs. The purpose of this study was to determine whether urban patterns of HR-HPV occurrence can be generalized to rural areas of the same developing country, using data from Mali, West Africa, as an example. METHODS: Urban and rural women in Mali participated in a structured interview and clinician exam, with collection of cervical samples for HPV DNA testing, to determine HR-HPV prevalence and correlates of infection. Correlates were assessed using bivariate analysis and logistic regression. RESULTS: A total of 414 women (n=202 urban women; n=212 rural women) were recruited across both settings. The prevalence of HR-HPV infection in rural women was nearly twice that observed in urban women (23% v. 12%). Earlier age of sexual debut and fewer pregnancies were associated with HR-HPV infection among urban women, but not rural women. Twenty-six percent of urban women who had sexual intercourse by age 14 had an HR-HPV infection, compared to only 9% of those who had later sexual debut (p<0.01). Overall, age, income, and polygamy did not appear to have a relationship with HR-HPV infection. CONCLUSIONS: Compared to urban women, rural women were significantly more likely to be infected with high-risk HPV. The patterns and risk factors of HR-HPV infection may be different between geographic areas, even within the same developing country. The high prevalence in both groups suggests that nearly all rural women and most urban women in Mali will be infected with HR-HPV during their lifetime, so the effects of risk factors may not be statistically apparent. To control HPV and cervical cancer in West Africa and the rest of the developing world, planners should prioritize vaccination in high-burden areas.


Subject(s)
Mass Screening/statistics & numerical data , Papillomavirus Infections/diagnosis , Papillomavirus Infections/epidemiology , Poverty/statistics & numerical data , Rural Population/statistics & numerical data , Urban Population/statistics & numerical data , Adult , Cross-Sectional Studies , Female , Humans , Mali/epidemiology , Middle Aged , Prevalence , Risk Factors , Sexual Behavior/statistics & numerical data , Women's Health , Young Adult
3.
Vaccine ; 30 Suppl 1: A71-8, 2012 Apr 27.
Article in English | MEDLINE | ID: mdl-22520140

ABSTRACT

The oral, pentavalent rotavirus vaccine (PRV), RotaTeq was assessed for prevention of severe rotavirus gastroenteritis (RVGE) in young children in two multi-site, randomized, placebo-controlled field trials; one in Asia (Vietnam and Bangladesh) and the other in sub-Saharan Africa (Ghana, Kenya and Mali). The efficacy results for the Mali site of the multi-country trial are presented here. We randomly assigned infants in a 1:1 ratio to receive 3 doses of PRV/placebo at approximately 6, 10, and 14 weeks of age. Gastroenteritis episodes were captured passively at the local health centers and by home visits. The primary study outcome was severe RVGE, as defined by a score of ≥ 11 using the Vesikari Clinical Scoring System occurring ≥ 14 days after the third dose until the end of the study. Other efficacy analyses included efficacy against severe RVGE through the first year and during the second years of life, as well as efficacy after receiving at least one dose of vaccine. In total, 1960 infants were enrolled in the trial at the Mali site and sera were collected on a subset of infants (approximately 150) for immunogenicity testing. In the first year of follow-up, largely due to cultural practices to visit traditional healers as the first point of care, the point estimate of efficacy was unreliable: the per protocol vaccine efficacy against severe RVGE was 1% (95% confidence interval [CI]: -431.7, 81.6); the intention-to-treat vaccine efficacy was 42.9% (95% CI: -125.7, 87.7). During the second year of follow-up, after the surveillance system was modified to adapt to local customs and health care seeking practices, the point estimate of per-protocol vaccine efficacy was 19.2% (95% CI: -23.1,47.3%). 82.5% of Malian infants (95% CI: 70.1,91.3%) who received PRV mounted a seroresponse (≥ 3-fold rise from baseline (prevaccination) to post-dose 3 vaccination) of anti-rotavirus immunoglobulin A antibody, with a post third-dose geometric mean titer (GMT) of 31.3 units/mL. By contrast, only 20.0% of placebo recipients (95% CI: 10.0, 33.7%) developed a seroresponse and the post-third dose GMT was 3.2 units/mL. None of the serious clinical adverse events observed were considered to be vaccine-related.


Subject(s)
Gastroenteritis/prevention & control , Rotavirus Infections/prevention & control , Rotavirus Vaccines/administration & dosage , Rotavirus Vaccines/immunology , Vaccination/methods , Administration, Oral , Antibodies, Viral/blood , Drug-Related Side Effects and Adverse Reactions/epidemiology , Female , Gastroenteritis/epidemiology , Gastroenteritis/pathology , Humans , Immunoglobulin A/blood , Infant , Male , Mali/epidemiology , Placebos/administration & dosage , Rotavirus Infections/epidemiology , Rotavirus Infections/pathology , Rotavirus Vaccines/adverse effects , Severity of Illness Index , Vaccination/adverse effects , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/immunology
4.
Trop Med Int Health ; 16(11): 1432-8, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21749583

ABSTRACT

OBJECTIVE: To investigate the epidemiology of human papillomavirus (HPV) infection in Malian women, for whom cervical cancer is the most common cancer and the second most common cause of cancer-related mortality. METHODS: Pilot study of 202 women aged 15-65 to determine the prevalence rate of high-risk HPV infection among unscreened Malian women. Information on risk factors was collected through a standardized, structured interview and clinical examination. High-risk (HR) HPV DNA was detected using signal amplification methods (hybrid capture II). RESULTS: High-risk HPV DNA was detected in 12% of unscreened women, while visual inspection after application of acetic acid and Lugol's iodine (VIA/VILI) identified suspicious abnormalities in 2.5% of unscreened women. Histopathological evaluation of VIA/VILI-positive biopsies revealed no evidence of cervical intraepithelial neoplasia or cervical cancer. The majority of infections occurred among women in the 15-24 year old range. Compared to women who were married or widowed, single women were 3.5 times more likely to be infected with HR HPV. CONCLUSIONS: The prevalence of infection with cancer causing types of HPV in this study was 12%. These prevalence estimates are consistent with what has been reported previously for other West African countries.


Subject(s)
Papillomavirus Infections/epidemiology , Uterine Cervical Neoplasms/epidemiology , Acetic Acid , Adolescent , Adult , Aged , Coloring Agents , DNA, Viral/analysis , Female , Humans , Iodides , Mali/epidemiology , Mass Screening/methods , Middle Aged , Nucleic Acid Amplification Techniques , Papillomaviridae/genetics , Papillomaviridae/metabolism , Pilot Projects , Risk Factors , Uterine Cervical Neoplasms/virology , Vaginal Smears/methods , Young Adult
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