Browsing by Author "Kagina, Benjamin"
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- ItemOpen AccessAn umbrella review of the available evidence syntheses to inform vaccination practices and policies for the COVID-19 pandemic in Africa(2023) Els, Krisna; Kagina, Benjamin; Muloiwa RudzaniBackground: In Africa, the rollout of COVID-19 vaccines lags other continents. The rollout in Africa started in the latter part of the first quarter of 2021 compared with earlier periods in high income settings. Optimal COVID-19 vaccination rollout in Africa should be guided by context-specific and up to date evidence. We conducted an umbrella review to identify, analyze and characterize the evidence syntheses that is available and has the potential to inform COVID-19 vaccination practices and policies in Africa. Methods: A systematic search for scoping reviews, systematic reviews, rapid reviews, and meta-analyses was performed in PubMed/Medline, Web of Science, Scopus (EMBASE), Epistemonikos and The Cochrane Library. Search outputs were exported to Rayyan software for screening. From the included studies, predefined outcomes were extracted and recorded on a data extraction form. Study characteristics, number and types of evidence syntheses were reported. Pooled results from the included studies were reported, including the statistical methods used. Where pooling of reported results had not been done and was feasible to do so, we conducted our own data pooling. Results: A total of 1111 papers were retrieved from all the databases. After removing duplicates and screening for inclusion, 15 papers were included: systematic reviews (n=4), systematic reviews and meta-analysis (n=7), meta-analysis alone (n=2), rapid review and meta- analysis (n=1), and a review of surveys (n=1). Results from the included studies were from 36 (66%) out of 55 African countries. The most abundant evidence was on the seroprevalence of antibodies against SARS-CoV-2 which ranged from 8.2% (95% CI: 0.8-22.3%) to 22% (95% CI 14%-31%). Conclusions: At the time of conducting this study, there was paucity of systematized evidence from majority of the African countries. Evidence syntheses gaps were evident for the incidence and severity of COVID-19 related outcomes, including hospitalization and mortality, as well as vaccine acceptance rates. Open Science Framework Registration: 10.17605/OSF.IO/PTB9W
- ItemOpen AccessCharacterisation of national immunisation programmes in countries experiencing public health emergencies within the WHO African region(2021) Chepkurui, Viola; Kagina, Benjamin; Amponsah-Dacosta, Edina; Haddison, Eposi ChristianaBackground: The World Health Organisation (WHO) Africa region experiences multiple public health emergencies (PHEs) annually. PHEs have been documented to affect the provision of health services including immunisation. To our knowledge, there is a scarcity of studies characterising PHEs and the performance of national immunisation programmes (NIPs) in countries within the WHO Africa region that have experienced PHEs. This study assessed PHEs (armed conflicts, disasters, and disease outbreaks) and the performance of NIPs in the context of PHEs using global and regional immunisation targets. Methods Countries in the WHO Africa region that were reported to benefit from the African Public Health Emergency Fund (APHEF) were used as case studies. Data on PHEs and immunisation indicators recorded between 2010 and 2019 in the study countries were extracted from different electronic PHE databases (the Emergency Events database, the Uppsala Conflict Data Program, the WHO Emergency Preparedness and Response, and the Program for Monitoring Emerging Diseases Mail) and the WHO/UNICEF immunisation database, respectively. The PHEs and immunisation indicators were stratified by country and summarised using descriptive statistics. The Mann-Whitney U test was carried out to determine the association between the frequency of PHEs and the performance of NIPs in the selected countries from 2010 to 2019. Statistical significance was defined at p-value < 0.05. Results Thirteen countries were included in this study. A total of 175 disease outbreaks, 288 armed conflicts, and 318 disasters were reported to have occurred within the 13 countries from 2010 to 2019. The Democratic Republic of Congo had the highest total PHE count (n=208), while Liberia had the lowest (n=20). Only three of the 13 countries had a median coverage value for the third dose of the combined Diphtheria, Tetanus, and Pertussis vaccine (DTP3) that had attained the target for ≥90% immunisation coverage. Higher counts of armed conflict and total PHEs were statistically significantly (p=0.03) associated with not attaining MNT elimination. Conclusion PHEs are prevalent in the WHO Africa region, irrespective of the level of a country's immunisation maturity. In absence of effective interventions, PHEs have the potential to derail the progress of NIPs in the WHO Africa region. As we enter the Immunisation Agenda 2030 era, this study advocates for the prioritisation of interventions to mitigate the impacts of PHEs on the NIPs.
- ItemOpen AccessEvidence-based vaccinology: supporting evidence-informed considerations to introduce routine hepatitis A immunization in South Africa(2023) Patterson, Jenna; Kagina, Benjamin; Cleary Susan; Muloiwa, Rudzani; Hussey, Gregory; Silal, SheetalHepatitis A is a vaccine preventable disease caused by the Hepatitis A Virus (HAV). Currently, South Africa is classified by the World Health Organization (WHO) as a high hepatitis A endemic region where 90% of children are assumed to be “naturally immunised” following HAV exposure before the age of 10 years old. In high hepatitis A endemic settings, routine vaccination against HAV is not necessary due to high rates of “natural immunization”. Recent data suggest a possible shift from high to intermediate HAV endemicity may be occurring in South Africa. Countries with intermediate HAV endemicity and no routine hepatitis A vaccination program have a high risk of experiencing hepatitis A outbreaks and high costs associated with care. Currently, there is no routine vaccination program against HAV in South Africa. The aim of this PhD was to generate evidence for decision making on whether a routine vaccination program against HAV should be considered for introduction into the South African Expanded Program on Immunizations (EPI-SA). The objectives included gathering context-specific evidence on the epidemiologic features of hepatitis A, clinical characteristics of the disease, hepatitis A vaccine characteristics and cost of case management. Using this evidence, the PhD estimated the future epidemiology of hepatitis A and impacts of routine hepatitis A vaccination scenarios in the country. The PhD's overall methods were informed by the principles of Evidence-Based Vaccinology for developing vaccine recommendations. The project included a mixed-methods approach: systematic reviews, a retrospective clinical folder review, mathematical modelling, and economic evaluation. A dynamic transmission model was built to forecast the future epidemiology of hepatitis A and to simulate the impacts of several different childhood hepatitis A vaccination strategies in South Africa. Selected findings have been published in relevant peer-reviewed journals. In addition, a technical dossier was prepared to submit to the South African National Advisory Group on Immunization (NAGI) on behalf of the Hepatitis A Working Group for considerations of introducing hepatitis A vaccination into the South African EPI.
- ItemOpen AccessHealth systems constraints and facilitators of national immunization programs in low- and middle- income countries(2019) Amponsah-Dacosta, Edina; Olivier, Jill; Kagina, BenjaminLike most health interventions, National Immunization Programs (NIPs) are embedded within health systems. This means that NIPs and health systems exist in a constant interaction. Vaccine preventable diseases are widely recognized as the chief cause of morbidity, disability and mortality worldwide and NIPs are understood to be one of the most cost-effective interventions against this burden. In low and middle- income countries (LMICs), where the burden of disease is high, NIPs have been reported to perform at suboptimal levels. It has been suggested that this suboptimal performance of NIPs can be associated with the poor state of health systems in LMIC. Despite this, the interaction between NIPs and health systems is poorly understood. In addition to this, systematic evidence on how health systems constraints and facilitators impact on the performance of NIPs in LMICs is scarce. To address this evidence gap, a systematic review study was conducted, that involved an initial scoping review of the evidence-base on NIPs and health systems in LMICs from which a logic model was developed. This logic model was then applied as a guide for a qualitative systematic review aimed at assessing the health systems constraints and facilitators of NIP performance in sub-Saharan Africa. The findings of this review suggest that well-performing NIPs are those that operate within enabling health systems, characterized by the availability of strong political endorsement for vaccines, clear governance structures and effective collaboration with global partners. Despite this, significant health systems constraints persist and include the limited capacity of health workers in sub-Saharan Africa, weak country infrastructure, poor service delivery, inadequate vaccine communication and ineffective community engagement in immunization programs. This systematic review study contributes to our limited understanding of the interaction between NIPs and health systems. In addition, the findings show how system-wide constraints and facilitators impact on the performance of NIPs. These findings have relevance for ongoing health systems strengthening initiatives, especially where NIPs are concerned.
- ItemOpen AccessThe uptake of the Prepex and Shang ring male circumcision devices among adolescent and adult males in Africa, a systematic review(2018) Rajab, Kakaire Menyha; Kagina, Benjamin; Abdullahi, Leila HusseinVoluntary medical male circumcision (VMMC) programs have been implemented in fourteen countries in sub Saharan Africa since 2007. The uptake of services has been suboptimal in some of the countries partly due to the widespread use of surgical methods. Circumcision using device methods was postulated to increase the uptake of VMMC services by making the procedure quicker and more appealing to men. We conducted a systematic review to establish the uptake and acceptability of the Prepex and Shang ring male circumcision devices in VMMC program countries. A metaanalysis was also performed. Methods: A comprehensive literature search from several databases was carried out to identify studies reporting VMCC coverage, uptake or acceptability of either the Prepex or Shang ring device methods. Search terms included, “non-surgical methods, male circumcision instrumentation as well as the individual device names such as Prepex, Shang ring, Gomco, Mogen, Plastibell, Accucirc, Alisklamp, Ismail Clamp, Tara Klamp, Unicirc, Smartclamp”. Electronic searches were complemented by going through the reference lists of the included studies. All searches were carried out on 12th May, 2017. Included studies must have been conducted between 1st April, 2007 and 28th February, 2017.The search was limited to studies among adolescents and adults in VMMC implementing countries. Two reviewers independently reviewed, rated, and abstracted data from each article. Uptake estimates were pooled in a meta-analysis and stratified according to the device method and participant age using Stata. Acceptability of device methods among recipients was summarized using four criteria and presented as proportions. Results: Of the 391 total articles retrieved, 25 studies incorporating observational and interventional study designs met the inclusion criteria. Of these 25 studies, 7 articles reported uptake of device method, 5 and 2 being on the Prepex and Shang ring devices respectively. The pooled uptake estimate was 75% (95% confidence interval 62% to 89%). Prepex uptake was estimated to be 73% while the Shang ring estimates were 82%. On stratification by population group, uptake of device methods among adolescents was 82% compared to 72% by adults. Majority (21) of the studies reported at least one of the criteria used to assess device acceptability. Acceptability of the two device methods was high: 95% of participants reported satisfaction with a device procedure. The devices were not associated with lengthy periods out of work, with 87% of participants reported to have resumed normal activities within two days after the procedure. Almost all (97%) participants circumcised with the device methods indicated they would recommend a device procedure to a friend or relative. Conclusion: Our findings showed a high uptake and acceptability of the two circumcision devices methods that have been prequalified by WHO for use among adolescents and adults. There is a dearth of evidence on the extent of utilization of devices for adolescent or adult circumcision and whether this has improved the overall uptake of VMMC services, thus emphasizing the need for more studies on this topic.
- ItemOpen AccessVaricella zoster virus-associated morbidity and mortality in Africa – a systematic review(BioMed Central, 2017-11-14) Hussey, Hannah; Abdullahi, Leila; Collins, Jamie; Muloiwa, Rudzani; Hussey, Gregory; Kagina, BenjaminBackground: Varicella zoster virus (VZV) causes varicella and herpes zoster. These vaccine preventable diseases are common globally. Most available data on VZV epidemiology are from industrialised temperate countries and cannot be used to guide decisions on the immunization policy against VZV in Africa. This systematic review aims to review the published data on VZV morbidity and mortality in Africa. Methods: All published studies conducted in Africa from 1974 to 2015 were eligible. Eligible studies must have reported any VZV epidemiological measure (incidence, prevalence, hospitalization rate and mortality rate). For inclusion in the review, studies must have used a defined VZV case definition, be it clinical or laboratory-based. Results: Twenty articles from 13 African countries were included in the review. Most included studies were crosssectional, conducted on hospitalized patients, and half of the studies used varying serological methods for diagnosis. VZV seroprevalence was very high among adults. Limited data on VZV seroprevalence in children showed very low seropositivity to anti-VZV antibodies. Co-morbidity with VZV was common. Conclusion: There is lack of quality data that could be used to develop VZV control programmes, including vaccination, in Africa. Trial registration: PROSPERO 2015: CRD42015026144.