Browsing by Author "Jaca, Anelisa"

Now showing 1 - 6 of 6
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    A global bibliometric analysis of research productivity on vaccine hesitancy from 1974 to 2019
    (Taylor & Francis, 2021-05) Jaca, Anelisa; Iwu-Jaja, Chinwe J.; Balakrishna, Yusentha; Pienaar, Elizabeth; Wiysonge, Charles S.
    Vaccine hesitancy is a phenomenon where individuals delay or refuse to take some or all vaccines. The objective of this study was to conduct a global bibliometric analysis of research productivity and identify country level indicators that could be associated with publications on vaccine hesitancy. We searched PubMed and Web of Science for publications from 1974 to 2019, and selected articles focused on behavioral and social aspects of vaccination. Data on country-level indicators were obtained from the World Bank. We used Spearman’s correlation and zero-inflated negative-binomial regression models to ascertain the association between country level indicators and the number of publications. We identified 4314 articles, with 1099 eligible for inclusion. The United States of America (461 publications, 41.9%), Canada (84 publications, 7.6%) and the United Kingdom (68 publications, 6.2%) had the highest number of publications. Although various country indicators had significant correlations with vaccine hesitancy publications, only gross domestic product (GDP) and gross national income (GNI) per capita were independent positive predictors of the number of publications. When the number of publications were standardized by GDP, the Gambia, Somalia and Malawi ranked highest in decreasing order. The United States, Canada and United Kingdom ranked highest (in that order) when standardized by current health expenditure. Overall, high-income countries were more productive in vaccine hesitancy research than low-and-middle-income countries. There is a need for more investment in research on vaccine hesitancy in low-and-middle-income countries.
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    Pandemic influenza preparedness in the WHO African region : are we ready yet?
    (BMC (part of Springer Nature), 2018) Sambala, Evanson Z.; Kanyenda, Tiwonge; Iwu, Chinwe J.; Iwu, Chidozie D.; Jaca, Anelisa; Wiysonge, Charles S.
    Background: Prior to the 2009 pandemic H1N1, and the unprecedented outbreak of Highly Pathogenic Avian Influenza (HPAI) caused by the H5N1 virus, the World Health Organization (WHO) called upon its Member States to develop preparedness plans in response to a new pandemic in humans. The WHO Member States responded to this call by developing national pandemic plans in accordance with the International Health Regulations (IHR) to strengthen the capabilities of Member States to respond to different pandemic scenarios. In this study, we aim to evaluate the quality of the preparedness plans in the WHO African region since their inception in 2005. Methods: A standard checklist with 61 binary indicators (“yes” or “no”) was used to assess the quality of the preparedness plans. The checklist was categorised across seven thematic areas of preparedness: preparation (16 indicators); coordination and partnership (5 indicators); risk communication (8 indicators); surveillance and monitoring (7 indicators); prevention and containment (10 indicators); case investigation and treatment (10 indicators) and ethical consideration (5 indicators). Four assessors independently scored the plans against the checklist. Results: Of the 47 countries in the WHO African region, a total of 35 national pandemic plans were evaluated. The composite score for the completeness of the pandemic plans across the 35 countries was 36%. Country-specific scores on each of the thematic indicators for pandemic plan completeness varied, ranging from 5% in Côte d’Ivoire to 79% in South Africa. On average, preparation and risk communication scored 48%, respectively, while coordination and partnership scored the highest with an aggregate score of 49%. Surveillance and monitoring scored 34%, while prevention and containment scored 35%. Case investigation and treatment scored 25%, and ethical consideration scored the lowest of 14% across 35 countries. Overall, our assessment shows that pandemic preparedness plans across the WHO African region are inadequate. Conclusions: Moving forward, these plans must address the gaps identified in this study and demonstrate clarity in their goals that are achievable through drills, simulations and tabletop exercises.
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    Protocol for a systematic review of the effects of interventions for vaccine stock management
    (BMC (part of Springer Nature), 2019-01-08) Iwu, Chinwe Juliana; Jaca, Anelisa; Abdullahi, Leila H.; Ngcobo, Ntombenhle Judith; Wiysonge, Charles Shey
    Background: Inadequate vaccine stock management in health facilities leads to vaccine stock-outs. The latter threatens the success of immunisation programmes. Countries have used various approaches to reduce stock-outs and improve vaccine availability, but we are not aware of a systematic review of these interventions. This protocol describes the methods we will use to assess the effects of existing approaches for improving vaccine stock management. Methods: We include randomised and non-randomised studies identified through a compehensive search of peer-reviewed and grey literature databases. We will search PubMed, Cochrane Central Register of Controlled Trials, Embase, Web of Science, PDQ-Evidence and Scopus. We will also search websites of the World Health Organisation (WHO), Global Alliance for Vaccine and Immunisation, PATH Vaccine Resources Library and United Nations Children’s Fund. In addition, we will search the WHO International Clinical Trials Registry Platform and reference lists of included studies and relevant reviews. Finally, we plan to do a citation search for included studies. We will use Cochrane recommended methods to screen search outputs, assess study eligibility and risk of bias, extract and analyse study results. We will use the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool to assess the certainty of the evidence on the effects of the interventions. Discussion: We believe that the findings of this review will serve as valuable information for policy makers on ways to improve vaccine stock management and vaccine availability. When vaccine availability is improved, those who need them, especially children, will be adequately protected from vaccine-preventable diseases.
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    A systematic review of strategies for reducing missed opportunities for vaccination
    (Elsevier, 2018) Jaca, Anelisa; Mathebula, Lindi; Iweze, Arthur; Pienaar, Elizabeth; Wiysonge, Charles S.
    Background: Missed opportunities for vaccination (MOVs) occur when persons eligible for vaccination visit a health facility and do not get the vaccines they need. We conducted a systematic review to assess effects of interventions for reducing MOVs. Methods: We searched PubMed, Scopus, and the Cochrane Central Register of Controlled Trials in April 2017. Three authors independently screened search outputs, reviewed potentially eligible papers, assessed risk of bias, and extracted data; resolving disagreements by consensus. We expressed study results as risk ratios (RR) with 95% confidence intervals (CI) and assessed the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool. Results: Six studies (five trials and one cohort study) met our inclusion criteria, all conducted in the United States of America. All six studies had various limitations and were classified as having a high risk of bias. We found moderate certainty evidence that the following interventions probably improve vaccination coverage: patient education (RR 1.92, 95% CI 1.38–2.68), patient tracking using community health workers (RR 1.18, 95% CI 1.11–1.25), and patient tracking and provider prompts (RR 1.24, 95% CI 1.18–1.31). In addition, we found low certainty evidence that concurrent interventions targeting health-facility (education, prompts, and audit and feedback) and family settings (phone calls) may increase vaccination coverage (RR 1.25, 95% CI 1.08–1.46). Conclusions: The currently available evidence suggests that patient education, patient tracking, outreach sessions, and provider prompts reduce missed opportunities for vaccination and improve vaccination coverage. Rigorous studies are required to confirm these findings and increase the certainty of the current evidence base. WHO is currently coordinating efforts to generate such evidence, especially from low-income and middle-income countries, and it is likely that the data will be available in the next few years.
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    Taking stock of vaccine hesitancy among migrants : a scoping review protocol
    (BMJ Publishing, 2020-05) Tankwanchi, Akhenaten Siankam; Jaca, Anelisa; Larson, Heidi J.; Wiysonge, Charles S.; Vermund, Sten H.
    Introduction: At the 72nd World Health Assembly of May 2019, WHO member states prioritised a global action plan to promote migrant and refugee health. Five months earlier, WHO had declared vaccine hesitancy—the reluctance to vaccinate despite the availability of vaccination services—as one of the top 10 threats to global health. Although vaccination is often a requirement for immigration, repeated outbreaks of vaccine-preventable diseases within certain immigrant communities in some host nations suggest that vaccine hesitancy could be a factor in their susceptibility to vaccine-preventable diseases. Studies of the prevalence and determinants of vaccine hesitancy among migrants globally seem to be lacking. This scoping review will (1) identify articles on vaccine hesitancy among migrants; (2) examine the extent and nature of the extant evidence; and (3) determine the value of undertaking a full systematic review. Methods and analysis: The framework for the scoping review proposed by the Joanna Briggs Institute will be used. The reporting will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. Studies published in English or French between January 1999 and December 2019 will be drawn from most or all of the following multidisciplinary databases: Africa-Wide Information, Allied and Complementary Medicine, Cochrane Library, Cumulative Index of Nursing and Allied Health Literature, Embase, Index Medicus for the Eastern Mediterranean Region, International Bibliography of Social Sciences, Literature in the Health Sciences in Latin America and the Caribbean, Medline, Proquest Theses/Dissertations, PsycInfo and Web of Science. The search will include an extensive list of keywords to capture multiple dimensions of confidence and hesitancy vis-à-vis vaccines among migrants. Findings will be reported through summary narratives, tables, flowcharts and evidence maps. Ethics and dissemination: This review is exempted from ethical approval and will be published in a peer-reviewed open-access journal to ensure wide dissemination.
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    Understanding the underlying drivers of obesity in Africa : a scoping review protocol
    (BMJ Publishing, 2020-11) Jaca, Anelisa; Iwu, Chinwe; Durão, Solange; Onyango, Adelheid W.; Wiysonge, Charles Shey
    Introduction: The worldwide prevalence of obesity and overweight has doubled since 1980, such that approximately a third of the world's population is reported as obese or overweight. Obesity rates have increased in all ages and both sexes irrespective of geographical area, ethnicity or socioeconomic status. Due to the high prevalence, related health consequences and costs of childhood and adult obesity, there is a need to comprehensively identify and assess the major underlying drivers of obesity and overweight in the African context. Methods and analysis: This scoping review will be carried out as per the methodological outline by Arksey and O'Malley. The search strategy will be developed and search performed in the Scopus and PubMed electronic databases. In the first search, we will identify concepts that are used as an equivalent to obesity and overweight. Subsequently, we will search for studies comprising of search terms on the underlying factors that drive the development of obesity and overweight. Lastly, we will check reference lists for additional publications. Abstracts and full-text studies will independently be screened by two authors. Ethics and dissemination: The proposed study will generate evidence from published data and hence does not require ethics approval. Evidence generated from this review will be disseminated through journal publications and conference presentations.