Browsing by Author "Kagina, Benjamin M"

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    Open Access
    A systematic review of the epidemiology of hepatitis A in Africa
    (2019-07-22) Patterson, Jenna; Abdullahi, Leila; Hussey, Gregory D; Muloiwa, Rudzani; Kagina, Benjamin M
    Abstract Background Hepatitis A, caused by the hepatitis A virus (HAV), is a vaccine preventable disease. In Low and Middle-Income Countries (LMICs), poor hygiene and sanitation conditions are the main risk factors contributing to HAV infection. There have been, however, notable improvements in hygiene and sanitation conditions in many LMICs. As a result, there are studies showing a possible transition of some LMICs from high to intermediate HAV endemicity. The World Health Organization (WHO) recommends that countries should routinely collect, analyse and review local factors (including disease burden) to guide the development of hepatitis A vaccination programs. Up-to-date information on hepatitis A burden is, therefore, critical in aiding the development of country-specific recommendations on hepatitis A vaccination. Methods We conducted a systematic review to present an up-to-date, comprehensive synthesis of hepatitis A epidemiological data in Africa. Results The main results of this review include: 1) the reported HAV seroprevalence data suggests that Africa, as a whole, should not be considered as a high HAV endemic region; 2) the IgM anti-HAV seroprevalence data showed similar risk of acute hepatitis A infection among all age-groups; 3) South Africa could be experiencing a possible transition from high to intermediate HAV endemicity. The results of this review should be interpreted with caution as the reported data represents research work with significant sociocultural, economic and environmental diversity from 13 out of 54 African countries. Conclusions Our findings show that priority should be given to collecting HAV seroprevalence data and re-assessing the current hepatitis A control strategies in Africa to prevent future disease outbreaks.
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    Descriptive analysis of routine childhood immunisation timelines in the Western Cape, South Africa
    (2021) Blose, Ntombifuthi J; Amponsah-Dacosta, Edina; Kagina, Benjamin M; Muloiwa, Rudzani
    Background: Adherence to the recommended age-specific immunisation schedules is critical in ensuring vaccine effectiveness against vaccine preventable diseases (VPDs). Delays in the uptake of routine childhood immunisations lead to an increase in children susceptible to VPDs. Catch-up vaccination campaigns are strategies aimed at minimising the time at risk of VPDs and alleviating missed immunisation opportunities. However, there is limited data on immunisation timeliness in the Western Cape to contribute to developing effective catch-up vaccination campaigns. Therefore, this study sought to assess the timeliness of age-specific routine childhood immunisation within the Western Cape province of South Africa. Methods: We reviewed 709 participant records from a prospective health-facility based study conducted between 2012 and 2016 in Cape Town, South Africa. The primary outcome of interest was receiving age-specific immunisations ≥ 4 weeks (28 days) of that recommended for age as per the South African Expanded Programme on Immunisation (EPI) schedule. Using secondary data, the prevalence of delayed uptake of immunisations and time-at-risk for each vaccine was determined using proportions and medians and interquartile range (IQR). Multivariable logistic regression (p< 0.05) was used to determine the association between potential socio-economic risk factors and delayed uptake of routine childhood immunisations. Results: A total of 652/709 (91.9%) participants with a median age of 11 [IQR 4.5 – 28.0] months were eligible for analysis in this study. A trend of decreasing immunisation coverage with increasing age was observed among study participants. Notably, a trend of increasing delay in the uptake of routine vaccines and an increasing median time-at-risk of VPDs in age-specific immunisations was observed with increasing age. The highest delay in the uptake of vaccine doses was observed among the 3rd dose of the DTP3 vaccine 163 (34.6%), while the lowest was seen among the birth doses [(BCG – 40 (6.5%) and OPV – 43 (7%)]. The longest median time-at-risk of VPDs, was with the 2nd dose of the measles vaccine dose [12.9 (IQRs 6.7-38.6) weeks] and the lowest was OPV birth dose [6.3 (5.3-9.1) weeks]. Multivariable logistic regression analysis showed that participants who attended pre-school or creche compared to those who did not, were protected against delaying uptake of the 3 rd dose of the Hepatitis B vaccine and 2nd dose of the measles vaccine. While those who had adult caregivers compared to those who had adolescent caregivers, were protected against delaying the uptake of the 1 st rotavirus vaccine dose. Participants from households of low and upper-middle socio-economic IQR compared to high socio-economic status (SES) based on SES scores calculated from household data (i.e., availability and sources of amenities such as water, fuel, toilets, and level of maternal education) were more likely to delay uptake of the 3 rd does of the Pneumococcal Conjugate Vaccine and the 1 st dose of the measles vaccine, respectively. Conclusion: Using DTP3 coverage as proxy for national immunisation coverage, immunisation coverage in this population fell below the recommended 95% immunisation coverage rate. Additional population delays in the uptake of vaccine doses increases the time during which infants and children are susceptible to potential fatal VPDs. The observed increase in delayed immunisation and increased time-at-risk of VPDs, calls for an urgent need to address timing of vaccination particularly in late infancy and in the second year of life. There is an urgent need to develop strategies aimed at mitigating factors associated with delay in uptake of routine childhood vaccines in the Western Cape Province. Since creche attendance conferred protection against the delay in uptake of vaccines, mitigation strategies implemented upstream by the department of basic education, as well as health and immunisation service providers should strengthen collaborations to ensure that timely vaccine uptake among creche attendees is regularly monitored. Where delays are identified, catch-up strategies can be implemented at educational facilities or referrals to immunization clinics. It is important that this strategy is coupled with caregiver and healthcare worker vaccine education on the importance of timely immunisation uptake. Education about timely vaccine uptake will aid in the provision of informed council from healthcare providers to – not only adult caregivers - but adolescent caregivers as well, with the aim to reduce delayed uptake of vaccine amongst those raised by adolescent caregiver. The health system and the Expanded Programme of Immunisation on South Africa (EPISA) should couple these interventions with effective mobile reminder systems. These reminder systems will particularly serve the purpose to remind those caregivers whose delay uptake of vaccines as a result of a busy schedule. This could improve adherence to the recommended childhood immunisation schedule. Generally, for such interventions to work, effective monitoring and surveillance of immunisation services and vaccines is critical in achieving a high immunisation coverage and timely uptake of vaccines. Future studies should continuously monitor immunisation coverage and timeliness data in the Western Cape Province and South Africa as a whole to support evidence-based strengthening of provincial and national immunisation services.
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    Determinants of vaccine hesitancy in Africa: a systematic review
    (2017) Paone, Alexander; Kagina, Benjamin M; Muloiwa, Rudzani; Hussey, Gregory D
    This MPH dissertation is a systematic review of the factors contributing to vaccine hesitancy in Africa. The dissertation comprises of the following three parts: The research protocol (Part A) outlines the background and proposed methods of the research. The protocol outlines the search strategy used to identify research eligible for this review according to defined criteria. The objective of this research was to identify determinants of vaccine hesitancy in Africa. The protocol describes data collection methods and the analysis plan of this research in order to address the objective. The literature review (Part B) provides a summary and interpretation of the current literature on barriers to vaccination, specifically vaccine hesitancy and its impacts on immunisation programs. The literature review identifies discord among literature in defining vaccine hesitancy and evaluating its presence and impact on varying populations, and reviews the attempts for standardisation by the Strategic Advisory Group of Experts Working Group on Vaccine Hesitancy. Lastly, the literature review identifies gaps in the literature, and suggests filling them ideally with a standardised metric. The manuscript (Part C) is presented in a format suitable for Vaccine journal submission. The manuscript includes a background, a description of the methods used, and a presentation and discussion of the results of the systematic review.
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    Hepatitis A seroprevalence in South Africa: Are we in epidemiological transition?
    (2018) Enoch, Annabel; Kagina, Benjamin M; Hussey, Gregory D; Andersson, Monique; Hardie, Diana
    Hepatitis A virus (HAV) is the most common cause of viral hepatitis worldwide. Infection with HAV is vaccine preventable, however, a vaccine against HAV is not included in the Expanded Programme on Immunization in South Africa (SA). South Africa was considered to be a high endemic country for hepatitis A in the past, hence there was no need for routine immunization against the virus. Our hypothesis is that SA is changing from high to intermediate endemic setting for hepatitis A. To test our hypothesis, we conducted a cross-sectional seroprevalence study in the 1-7 year age group in the Western Cape Province. Our samples for this study were from specimens, collected between August and October 2015, sent for routine diagnosis to referral hospitals in the Western Cape Province. We tested remaining serum of 482 samples sent for routine tests. A Siemens enzyme immunoassay was used to test for hepatitis A antibodies. We also analysed hepatitis A test results from the National Health Laboratory Services (NHLS) Disa*Lab database at Groote Schuur hospital from 2009-2014, as well as hepatitis A surveillance data from the National Institute for Communicable Diseases (NICD) from 2009-2014, to look at the past hepatitis A prevalence trend. Our cross-sectional study showed the seroprevalence to be 44.1% in the 1-7 year age group. The NHLS data showed a seroprevalence of <90% up to age 10 years, indicating intermediate endemicity. The NICD data showed that a substantial number of symptomatic hepatitis A infections occurred in the 7-40 year age group, suggesting an increasing proportion of a susceptible population to HAV infection. Taken together, these results indicate the need for further studies designed to aid the development of vaccination policies against HAV infection in South Africa.
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    Knowledge, attitudes and practices on adolescent vaccination among parents, teachers and adolescents in Africa: a systematic review protocol
    (BioMed Central, 2014-09-09) Abdullahi, Leila H; Kagina, Benjamin M; Cassidy, Tali; Adebayo, Esther F; Wiysonge, Charles S; Hussey, Gregory D
    Background: Vaccines are the most successful and cost-effective public health interventions available to avert vaccine-preventable diseases and deaths. Despite progress in the field of adolescent health, many young people in Africa still get sick and die from vaccine-preventable diseases due to lack of vaccination. Parents, adolescents and teachers are key players with regard to implementation of adolescent vaccination policies. Therefore, understanding their knowledge, attitudes and practices towards adolescent vaccination may provide clues on what can be done to improve vaccine uptake among adolescents. The aim of this study is to conduct a qualitative and quantitative systematic review on knowledge, attitudes and practices on adolescent vaccination among parents, teachers and adolescents in Africa. Methods: We will include both quantitative and qualitative primary studies. Eligible quantitative studies include both intervention and observational studies. Qualitative studies to be included are focus group discussions, direct observations, in-depth interviews and case ethnographic studies. We will search PubMed, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, WHOLIS, Africa Wide and CINAHL for eligible studies with no time and language limits. We will also check reference lists of included studies for other eligible reports. Two authors will independently screen the search output, select studies and extract data, resolving discrepancies by consensus and discussion. We will analyse qualitative data using thematic analysis where applicable, and quantitative studies findings will be presented in a narrative synthesis form based on the outcomes. Discussion: The findings from this systematic review will guide the identification of gaps on knowledge, attitudes and practices among the key role players on adolescent vaccination. We anticipate that our findings will guide the development of adolescent-focused vaccination policy in Africa, which is virtually non-existent at present. Systematic review registration: This review is registered with PROSPERO, registration number CRD42014010395. .
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    A retrospective study assessing the clinical outcomes and costs of acute hepatitis A in Cape Town, South Africa
    (2022-01-11) Patterson, Jenna; Cleary, Susan; Silal, Sheetal P; Hussey, Gregory D; Enoch, Annabel; Korsman, Stephen; Goddard, Elizabeth; Setshedi, Mashiko; Spearman, Wendy C; Kagina, Benjamin M; Muloiwa, Rudzani
    Background While some evidence has been demonstrated the cost-effectiveness of routine hepatitis A vaccination in middle-income countries, the evidence is still limited in other settings including in South Africa. Given this, the evidence base around the cost of care for hepatitis A needs to be developed towards considerations of introducing hepatitis A vaccines in the national immunisation schedule and guidelines. Objectives To describe the severity, clinical outcomes, and cost of hepatitis A cases presenting to two tertiary healthcare centers in Cape Town, South Africa. Methods We conducted a retrospective folder review of patients presenting with hepatitis A at two tertiary level hospitals providing care for urban communities of metropolitan Cape Town, South Africa. Patients included in this folder review tested positive for hepatitis A immunoglobulin M between 1 January 2008 and 1 March 2018. Results In total, 239 folders of hepatitis A paediatric patients < 15 years old and 212 folders of hepatitis A adult patients $$\ge$$ ≥ 15 years old were included in the study. Before presenting for tertiary level care, more than half of patients presented for an initial consultation at either a community clinic or general physician. The mean length of hospital stay was 7.45 days for adult patients and 3.11 days for paediatric patients. Three adult patients in the study population died as a result of hepatitis A infection and 29 developed complicated hepatitis A. One paediatric patient in the study population died as a result of hepatitis A infection and 27 developed complicated hepatitis A, including 4 paediatric patients diagnosed with acute liver failure. The total cost per hepatitis A hospitalisation was $1935.41 for adult patients and $563.06 for paediatric patients, with overhead costs dictated by the length of stay being the largest cost driver. Conclusion More than 1 in every 10 hepatitis A cases (13.3%) included in this study developed complicated hepatitis A or resulted in death. Given the severity of clinical outcomes and high costs associated with hepatitis A hospitalisation, it is important to consider the introduction of hepatitis A immunisation in the public sector in South Africa to potentially avert future morbidity, mortality, and healthcare spending.
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    Safety of licensed vaccines in HIV-infected persons: a systematic review protocol
    (2014-09-11) Kagina, Benjamin M; Wiysonge, Charles S; Lesosky, Maia; Madhi, Shabir A; Hussey, Gregory D
    Abstract Background Safety of vaccines remains a cornerstone of building public trust on the use of these cost-effective and life-saving public health interventions. In some settings, particularly Sub-Saharan Africa, there is a high prevalence of HIV infection and a high burden of vaccine-preventable diseases. There is evidence suggesting that the immunity induced by some commonly used vaccines is not durable in HIV-infected persons, and therefore, repeated vaccination may be considered to ensure optimal vaccine-induced immunity in this population. However, some vaccines, particularly the live vaccines, may be unsafe in HIV-infected persons. There is lack of evidence on the safety profile of commonly used vaccines among HIV-infected persons. We are therefore conducting a systematic review to assess the safety profile of routine vaccines administered to HIV-infected persons. Methods/Design We will select studies conducted in any setting where licensed and effective vaccines were administered to HIV-infected persons. We will search for eligible studies in PubMed, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, Africa-Wide, PDQ-Evidence and CINAHL as well as reference lists of relevant publications. We will screen search outputs, select studies and extract data in duplicate, resolving discrepancies by discussion and consensus. Discussion Globally, immunisation is a major public health strategy to mitigate morbidity and mortality caused by various infectious disease-causing agents. In general, there are efforts to increase vaccination coverage worldwide, and for these efforts to be successful, safety of the vaccines is paramount, even among people living with HIV, who in some situations may require repeated vaccination. Results from this systematic review will be discussed in the context of the safety of routine vaccines among HIV-infected persons. From the safety perspective, we will also discuss whether repeat vaccination strategies may be feasible among HIV-infected persons. Systematic review registration PROSPERO CRD42014009794 .
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    School based versus supplemental vaccination strategies in the delivery of vaccines to 5-19 year olds in Africa - a systematic review
    (2017) Haddison, Christiana Eposi; Kagina, Benjamin M; Abdullahi, Leila H; Muloiwa, Rudzani; Hussey, Gregory D
    Background: Some vaccine preventable diseases still remain a public health burden in many African countries. The occurrence of vaccine preventable diseases in all age groups has led to the realization of the need to extend routine immunisation services to school age children and adolescents. Supplemental immunisation activities (SIAs) and school based vaccination (SBV) are two common strategies used to complement the EPI in vaccine delivery. Therefore, this review aimed to assess the effectiveness of SIAs compared to SBV in the administration of vaccines to 5-19 year olds in Africa. Methods and findings: Systematic review methods (protocol number CRD42017057475) were used to address our study aim. Electronic databases were searched up to March 30, 2017 for primary studies investigating the delivery of vaccines via SIAs or SBV to 5-19 year olds. To be included in the review, studies must have reported any of the following outcomes: vaccination coverage, cost of the vaccination strategy or effect of the strategy on routine immunisation. During the search, no restriction was placed on language or the study period. The search was complemented by browsing reference lists of potential studies. Out of the 4938 studies identified, 31 studies met our inclusion criteria. Both SIAs and SBV showed high vaccination coverage. This result should be interpreted with caution due to the high heterogeneity observed across the included studies. The SIAs reported a higher coverage of 91% (95% CI: 84%, 98%) than SBV which had a coverage of 75% (95% CI: 67%, 83%). In most settings, SBV was reported to be more expensive than SIAs. The SIAs were found to negatively affect routine immunisation services. Conclusions: Both SIAs and SBV are routinely used to complement the EPI in the delivery of vaccines in Africa. In settings where school enrolment is suboptimal as is the case in many African countries, our results show SIAs may be more effective in reaching school age children and adolescents than SBV. The SBV has only been tested in the delivery of two or three dose HPV vaccine to adolescent girls, whereas SIAs have been tested in the delivery of different types of vaccines. Our results re-iterate the importance of systematic evidence to best inform African authorities on the optimal delivery strategies of vaccines targeting school age children and adolescents into their immunisation programme.
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    Screening strategies for adults with type 2 diabetes mellitus
    (2022) Mearns, Helen; Kagina, Benjamin M; Kredo, Tamara; Schmidt, Bey-Marrié
    There are insufficient randomized controlled trials to address whether screening for type 2 diabetes mellitus (T2DM) improves health outcomes. This systematic review sought to cast a wider net and synthesise evidence from non-randomised intervention studies to assess the effectiveness of T2DM screening in adults for reducing mortality and T2DM-associated morbidity. We searched PubMed/MEDLINE, Scopus, Web of Science, CINAHL, Academic Search Premier and Health Source Nursing Academic (inception onwards; last search July 2021). We included non-randomised intervention studies that assessed T2DM screening compared to no screening, in adults without known T2DM. Screening was performed independently by two reviewers. Data was abstracted by one reviewer and checked by a second, as was risk of bias (ROBINS-I) and certainty of evidence (GRADE). A narrative summary was performed. We screened 10,892 records, retrieving 67 for full-text screening with one record meeting inclusion criteria. The study was a prospective cohort comparing T2DM screening versus no screening. It included adults, 40 - 65 years, with no known T2DM from a single community practice in Ely, England (N = 4,936) and evaluated outcomes at two time periods. The study was assessed as having moderate risk of bias. There may be little or no difference in mortality between those who were invited to screening versus those who were not invited (1990-1999: adjusted hazard ratio (aHR) 0.79 [95% confidence interval (CI) 0.63 – 1.00], n = 4,936, low certainty evidence and 2000 - 2008: aHR 1.18 [95% CI 0.93 - 1.51], n = 3,002, low certainty evidence). We found only one study reporting the effectiveness of screening for T2DM in adults. Therefore, despite ongoing T2DM screening in clinical care, this review highlights an important research gap in understanding the true health benefits of screening.
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    The burden of laboratory-confirmed pertussis in low- and middle-income countries since the inception of the Expanded Programme on Immunisation (EPI) in 1974: a systematic review and meta-analysis
    (2020-08-28) Muloiwa, Rudzani; Kagina, Benjamin M; Engel, Mark E; Hussey, Gregory D
    Abstract Background An effective vaccine against Bordetella pertussis was introduced into the Expanded Programme on Immunisation (EPI) by WHO in 1974, leading to a substantial global reduction in pertussis morbidity and mortality. In low- and middle-income countries (LMICs), however, the epidemiology of pertussis remains largely unknown. This impacts negatively on pertussis control strategies in these countries. This study aimed to systematically and comprehensively review published literature on the burden of laboratory-confirmed pertussis in LMICs over the 45 years of EPI. Methods Electronic databases were searched for relevant literature (1974 to December 2018) using common and MeSH terms for pertussis. Studies using PCR, culture or paired serology to confirm Bordetella pertussis and parapertussis in symptomatic individuals were included if they had clearly defined numerators and denominators to determine prevalence and mortality rates. Results Eighty-two studies (49,167 participants) made the inclusion criteria. All six WHO regions were represented with most of the studies published after 2010 and involving mainly upper middle-income countries (n = 63; 77%). PCR was the main diagnostic test after the year 2000. The overall median point prevalence of PCR-confirmed Bordetella pertussis was 11% (interquartile range (IQR), 5–27%), while culture-confirmed was 3% (IQR 1–9%) and paired serology a median of 17% (IQR 3–23%) over the period. On average, culture underestimated prevalence by 85% (RR = 0.15, 95% CI, 0.10–0.22) compared to PCR in the same studies. Risk of pertussis increased with HIV exposure [RR, 1.4 (95% CI, 1.0–2.0)] and infection [RR, 2.4 (95% CI, 1.1–5.1)]. HIV infection and exposure were also related to higher pertussis incidences, higher rates of hospitalisation and pertussis-related deaths. Pertussis mortality and case fatality rates were 0.8% (95% CI, 0.4–1.4%) and 6.5% (95% CI, 4.0–9.5%), respectively. Most deaths occurred in infants less than 6 months of age. Conclusions Despite the widespread use of pertussis vaccines, the prevalence of pertussis remains high in LMIC over the last three decades. There is a need to increase access to PCR-based diagnostic confirmation in order to improve surveillance. Disease control measures in LMICs must take into account the persistent significant infant mortality and increased disease burden associated with HIV infection and exposure.
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    The burden of pertussis in low- and middle-income countries since the inception of the Expanded Programme on Immunization (EPI) in 1974: a systematic review protocol
    (2015-05-01) Muloiwa, Rudzani; Kagina, Benjamin M; Engel, Mark E; Hussey, Gregory D
    Abstract Background Vaccine against pertussis has been in use for several decades. Despite the widespread use of pertussis vaccine, evidence shows resurgence of pertussis in high-income countries. Pertussis surveillance data is largely missing from low- and middle-income countries (LMICs). Without data on trends of pertussis, it is difficult to review and amend pertussis control policies in any country. We propose conducting a systematic review to evaluate the burden and trends of pertussis in LMICs since 1974. Methods/design Common and medical subject heading (MeSH) terms for pertussis and LMICs will be used to search electronic databases for the relevant literature published between 1974 and December 2014. Only studies from LMICs that fulfils World Health Organisation (WHO) or CDC pertussis case definitions will be included. The studies must have a clear numerator and denominator in a well-defined population. Risk of bias will be evaluated by assessing all qualifying full-text articles for quality and eligibility using a modified quality score assessment tool. Standardised data extraction will be carried out after which descriptions of trends in the prevalence, incidence, as well as mortality rate and case fatality rate, will be done. Where sufficient data is available, the results will be stratified by age group, geography, location, vaccination and HIV status. Discussion The systematic review proposed by this protocol seeks to address the knowledge gap in the epidemiology of pertussis in LMICs for the first time. It is anticipated that the background epidemiological trends of pertussis in LMICs that our study will provide could be used in the planning for the control of pertussis. Systematic review registration PROSPERO CRD42015015159