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1.
Int J Infect Dis ; 2022 Nov 24.
Article in English | MEDLINE | ID: covidwho-2229309

ABSTRACT

OBJECTIVE: We aimed to compare clinical severity of Omicron BA.4/BA.5 infection with BA.1 and earlier variant infections among laboratory-confirmed SARS-CoV-2 cases in the Western Cape, South Africa, using timing of infection to infer the lineage/variant causing infection. METHODS: We included public sector patients aged ≥20 years with laboratory-confirmed COVID-19 between 1-21 May 2022 (BA.4/BA.5 wave) and equivalent prior wave periods. We compared the risk between waves of (i) death and (ii) severe hospitalization/death (all within 21 days of diagnosis) using Cox regression adjusted for demographics, comorbidities, admission pressure, vaccination and prior infection. RESULTS: Among 3,793 patients from the BA.4/BA.5 wave and 190,836 patients from previous waves the risk of severe hospitalization/death was similar in the BA.4/BA.5 and BA.1 waves (adjusted hazard ratio (aHR) 1.12; 95% confidence interval (CI) 0.93; 1.34). Both Omicron waves had lower risk of severe outcomes than previous waves. Prior infection (aHR 0.29, 95% CI 0.24; 0.36) and vaccination (aHR 0.17; 95% CI 0.07; 0.40 for at least 3 doses vs. no vaccine) were protective. CONCLUSION: Disease severity was similar amongst diagnosed COVID-19 cases in the BA.4/BA.5 and BA.1 periods in the context of growing immunity against SARS-CoV-2 due to prior infection and vaccination, both of which were strongly protective.

2.
Vaccines (Basel) ; 10(8)2022 Jul 27.
Article in English | MEDLINE | ID: covidwho-1969524

ABSTRACT

The challenge of vaccine hesitancy, a growing global concern in the last decade, has been aggravated by the COVID-19 pandemic. The need for monitoring vaccine sentiments and early detection of vaccine hesitancy in a population recommended by the WHO calls for the availability of contextually relevant tools and measures. This scoping review covers a ten year-period from 2010-2019 which included the first nine years of the decade of vaccines and aims to give a broad overview of tools and measures, and present a summary of their nature, similarities, and differences. We conducted the review using the framework for scoping reviews by Arksey and O'Malley (2005) and reported it following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews' guidelines. Of the 26 studies included, only one was conducted in the WHO African Region. Measures for routine childhood vaccines were found to be the most preponderant in the reviewed literature. The need for validated, contextually relevant tools in the WHO Africa Region is essential, and made more so by the scourge of the ongoing pandemic in which vaccination is critical for curtailment.

3.
Vaccines ; 10(5):785, 2022.
Article in English | ProQuest Central | ID: covidwho-1871458

ABSTRACT

Despite the substantial efforts at ensuring universal access to routine immunisation services among children in South Africa, major gaps in immunisation coverage remain. This study assessed the magnitude of missed opportunities for vaccination (MOV) and associated factors among children aged 0–23 months attending primary health care (PHC) facilities in Cape Town. We used multilevel binomial logistic regression models to explore individual and contextual factors associated with MOV, with children aged 0–23 months at Level 1, nested within PHC facilities (Level 2). A total of 674 children and their caregivers were enrolled. MOV prevalence was 14.1%, ranging from 9.1% to 18.9% across sub-districts. Dose-specific MOV prevalence was highest for the second dose of measles vaccine (9.5%) and lowest for the first dose of rotavirus vaccine (0.6%). The likelihood of a child experiencing MOV was significantly associated with caregivers’ low level of education (Odds ratio (OR) = 3.53, 95% credible interval (CrI): 1.13–11.03), recent receipt of immunisation messages (OR = 0.46, 95%CrI: 0.25–0.87), shared immunisation decision making by both parents (OR = 0.21, 95%CrI: 0.07–0.62) and health facility staff number (OR = 0.18, 95%CrI: 0.06–0.61). The burden of MOV among children in Cape Town is influenced by individual and contextual factors, which provide important opportunities for quality improvement and broader strategies to improve routine immunisation service delivery.

4.
Trop Med Int Health ; 27(6): 564-573, 2022 06.
Article in English | MEDLINE | ID: covidwho-1784751

ABSTRACT

OBJECTIVES: The objective was to compare COVID-19 outcomes in the Omicron-driven fourth wave with prior waves in the Western Cape, assess the contribution of undiagnosed prior infection to differences in outcomes in a context of high seroprevalence due to prior infection and determine whether protection against severe disease conferred by prior infection and/or vaccination was maintained. METHODS: In this cohort study, we included public sector patients aged ≥20 years with a laboratory-confirmed COVID-19 diagnosis between 14 November and 11 December 2021 (wave four) and equivalent prior wave periods. We compared the risk between waves of the following outcomes using Cox regression: death, severe hospitalisation or death and any hospitalisation or death (all ≤14 days after diagnosis) adjusted for age, sex, comorbidities, geography, vaccination and prior infection. RESULTS: We included 5144 patients from wave four and 11,609 from prior waves. The risk of all outcomes was lower in wave four compared to the Delta-driven wave three (adjusted hazard ratio (aHR) [95% confidence interval (CI)] for death 0.27 [0.19; 0.38]. Risk reduction was lower when adjusting for vaccination and prior diagnosed infection (aHR: 0.41, 95% CI: 0.29; 0.59) and reduced further when accounting for unascertained prior infections (aHR: 0.72). Vaccine protection was maintained in wave four (aHR for outcome of death: 0.24; 95% CI: 0.10; 0.58). CONCLUSIONS: In the Omicron-driven wave, severe COVID-19 outcomes were reduced mostly due to protection conferred by prior infection and/or vaccination, but intrinsically reduced virulence may account for a modest reduction in risk of severe hospitalisation or death compared to the Delta-driven wave.


Subject(s)
COVID-19 , Clinical Laboratory Techniques , SARS-CoV-2 , Adult , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/virology , COVID-19 Testing , COVID-19 Vaccines/administration & dosage , Cohort Studies , Female , Humans , Male , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Seroepidemiologic Studies , South Africa/epidemiology , Young Adult
5.
Vaccines (Basel) ; 10(3)2022 Mar 16.
Article in English | MEDLINE | ID: covidwho-1765972

ABSTRACT

Vaccination, and particularly childhood vaccination, is widely acknowledged as one of the greatest public health interventions in history. Nevertheless, challenges exist that threaten the progress of childhood vaccination in many parts of the world. We investigated challenges to vaccination experienced by point-of-care vaccinators in the Cape Town Metropolitan District (Cape Metro), and reported on their current and proposed efforts to combat these challenges. Semi-structured interviews were conducted with 19 vaccinators in 16 purposively selected healthcare facilities in the Cape Metro from September to November 2019. Interviews were transcribed and analysed using thematic and narrative analysis methods. Challenges of both the demand and the supply side of routine vaccination were reported by the study participants, as were contextual challenges such as community safety issues. Defaulting was the most common challenge encountered, reported by 16 of the 19 participants. The use of computerized appointment systems, the enlistment of community health workers to track down defaulters, and the use of certificates to incentivize caregivers are part of the creative ways of mitigating some of the challenges encountered by these vaccinators. Their insightful recommendations can positively influence the landscape of childhood vaccination uptake in the Cape Metro and beyond if adapted and applied.

6.
Lancet ; 399(10330): 1141-1153, 2022 03 19.
Article in English | MEDLINE | ID: covidwho-1747473

ABSTRACT

BACKGROUND: We aimed to assess the effectiveness of a single dose of the Ad26.COV2.S vaccine (Johnson & Johnson) in health-care workers in South Africa during two waves of the South African COVID-19 epidemic. METHODS: In the single-arm, open-label, phase 3B implementation Sisonke study, health-care workers aged 18 years and older were invited for vaccination at one of 122 vaccination sites nationally. Participants received a single dose of 5 × 1010 viral particles of the Ad26.COV2.S vaccine. Vaccinated participants were linked with their person-level data from one of two national medical insurance schemes (scheme A and scheme B) and matched for COVID-19 risk with an unvaccinated member of the general population. The primary outcome was vaccine effectiveness against severe COVID-19, defined as COVID-19-related admission to hospital, hospitalisation requiring critical or intensive care, or death, in health-care workers compared with the general population, ascertained 28 days or more after vaccination or matching, up to data cutoff. This study is registered with the South African National Clinical Trial Registry, DOH-27-022021-6844, ClinicalTrials.gov, NCT04838795, and the Pan African Clinical Trials Registry, PACTR202102855526180, and is closed to accrual. FINDINGS: Between Feb 17 and May 17, 2021, 477 102 health-care workers were enrolled and vaccinated, of whom 357 401 (74·9%) were female and 119 701 (25·1%) were male, with a median age of 42·0 years (33·0-51·0). 215 813 vaccinated individuals were matched with 215 813 unvaccinated individuals. As of data cutoff (July 17, 2021), vaccine effectiveness derived from the total matched cohort was 83% (95% CI 75-89) to prevent COVID-19-related deaths, 75% (69-82) to prevent COVID-19-related hospital admissions requiring critical or intensive care, and 67% (62-71) to prevent COVID-19-related hospitalisations. The vaccine effectiveness for all three outcomes were consistent across scheme A and scheme B. The vaccine effectiveness was maintained in older health-care workers and those with comorbidities including HIV infection. During the course of the study, the beta (B.1.351) and then the delta (B.1.617.2) SARS-CoV-2 variants of concerns were dominant, and vaccine effectiveness remained consistent (for scheme A plus B vaccine effectiveness against COVID-19-related hospital admission during beta wave was 62% [95% CI 42-76] and during delta wave was 67% [62-71], and vaccine effectiveness against COVID-19-related death during beta wave was 86% [57-100] and during delta wave was 82% [74-89]). INTERPRETATION: The single-dose Ad26.COV2.S vaccine shows effectiveness against severe COVID-19 disease and COVID-19-related death after vaccination, and against both beta and delta variants, providing real-world evidence for its use globally. FUNDING: National Treasury of South Africa, the National Department of Health, Solidarity Response Fund NPC, The Michael & Susan Dell Foundation, The Elma Vaccines and Immunization Foundation, and the Bill & Melinda Gates Foundation.


Subject(s)
COVID-19 , HIV Infections , Vaccines , Ad26COVS1 , Adolescent , Adult , Aged , COVID-19/epidemiology , COVID-19/prevention & control , Female , Humans , Male , SARS-CoV-2 , South Africa/epidemiology
7.
Vaccines (Basel) ; 9(11)2021 Oct 27.
Article in English | MEDLINE | ID: covidwho-1488800

ABSTRACT

Healthcare workers were the first group scheduled to receive COVID-19 vaccines when they became available in South Africa. Therefore, estimating vaccine confidence levels and intention to receive COVID-19 vaccines among healthcare workers ahead of the national vaccination roll-out was imperative. We conducted an online survey from 4 February to 7 March 2021, to assess vaccine sentiments and COVID-19 vaccine intentions among healthcare staff and students at a tertiary institution in South Africa. We enrolled 1015 participants (74.7% female). Among the participants, 89.5% (confidence interval (CI) 87.2-91.4) were willing to accept a COVID-19 vaccine, 95.4% (CI 93.9-96.6) agreed that vaccines are important for them, 95.4% (CI 93.8-96.6) that vaccines are safe, 97.4% (CI 96.2-98.3) that vaccines are effective, and 96.1% (CI 94.6-97.2) that vaccines are compatible with religion. Log binomial regression revealed statistically significant positive associations between COVID-19 vaccine acceptance and the belief that vaccines are safe (relative risk (RR) 32.2, CI 4.67-221.89), effective (RR 21.4, CI 3.16-145.82), important for children (RR 3.5, CI 1.78-6.99), important for self (RR 18.5, CI 4.78-71.12), or compatible with religion (RR 2.2, CI 1.46-3.78). The vaccine confidence levels of the study respondents were highly positive. Nevertheless, this could be further enhanced by targeted interventions.

9.
Vaccines (Basel) ; 9(7)2021 Jun 23.
Article in English | MEDLINE | ID: covidwho-1289035

ABSTRACT

Despite South Africa's substantial investments in and efforts at ensuring universal access to immunisation services, progress has stalled and remains suboptimal across provinces and districts. An additional challenge is posed by the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has disrupted immunisation services globally, including in South Africa. While there is growing evidence that missed opportunities for vaccination (MOV) are a major contributor to suboptimal immunisation progress globally, not much is known about the burden and determinants of MOV in the South African context. Herein, we make a case for assessing MOV as a strategy to address current immunisation coverage gaps while mitigating the adverse impacts of the COVID-19 pandemic on immunisation services. We illustrate a practical implementation research approach to assessing the burden of MOV among children in primary care settings; for understanding the factors associated with MOV; and for designing, implementing, and evaluating context-appropriate quality improvement interventions for addressing missed opportunities. Such efforts are vital for building health system resilience and maintaining immunisation programme capacity to optimally deliver essential health services such as routine childhood immunisation, even during pandemics.

10.
Am J Trop Med Hyg ; 104(4): 1179-1187, 2021 Feb 11.
Article in English | MEDLINE | ID: covidwho-1262647

ABSTRACT

Most African countries have recorded relatively lower COVID-19 burdens than Western countries. This has been attributed to early and strong political commitment and robust implementation of public health measures, such as nationwide lockdowns, travel restrictions, face mask wearing, testing, contact tracing, and isolation, along with community education and engagement. Other factors include the younger population age strata and hypothesized but yet-to-be confirmed partially protective cross-immunity from parasitic diseases and/or other circulating coronaviruses. However, the true burden may also be underestimated due to operational and resource issues for COVID-19 case identification and reporting. In this perspective article, we discuss selected best practices and challenges with COVID-19 contact tracing in Nigeria, Rwanda, South Africa, and Uganda. Best practices from these country case studies include sustained, multi-platform public communications; leveraging of technology innovations; applied public health expertise; deployment of community health workers; and robust community engagement. Challenges include an overwhelming workload of contact tracing and case detection for healthcare workers, misinformation and stigma, and poorly sustained adherence to isolation and quarantine. Important lessons learned include the need for decentralization of contact tracing to the lowest geographic levels of surveillance, rigorous use of data and technology to improve decision-making, and sustainment of both community sensitization and political commitment. Further research is needed to understand the role and importance of contact tracing in controlling community transmission dynamics in African countries, including among children. Also, implementation science will be critically needed to evaluate innovative, accessible, and cost-effective digital solutions to accommodate the contact tracing workload.


Subject(s)
COVID-19/prevention & control , Communicable Disease Control/organization & administration , Contact Tracing/methods , Humans , Nigeria/epidemiology , Practice Guidelines as Topic , Rwanda/epidemiology , SARS-CoV-2 , South Africa/epidemiology , Uganda/epidemiology
11.
BMJ Open ; 11(5): e049877, 2021 05 13.
Article in English | MEDLINE | ID: covidwho-1228888

ABSTRACT

INTRODUCTION: The outbreak of novel COVID-19 caught the world off guard in the first quarter of 2020. To stem the tide of this pandemic, there was acceleration of the development, testing and prelicensure approval for emergency use of some COVID-19 vaccine candidates. This led to raised public concern about their safety and efficacy, compounding the challenges of vaccine hesitancy. The onus of managing and administering these vaccines to a sceptical populace when they do become available rests mostly on the shoulders of healthcare workers (HCWs). Therefore, the vaccine confidence levels of HCWs become critical to the success of vaccination endeavours. This proposed study aims to estimate the level of vaccine confidence and the intention to receive a COVID-19 vaccine among future HCWs and their trainers at a specific university in Cape Town, South Africa, and to identify any vaccination concerns early for targeted intervention. METHODS AND ANALYSIS: This proposed study is a cross-sectional survey study. An online questionnaire will be distributed to all current staff and students of the Faculty of Medicine Health Sciences of Stellenbosch University in Cape Town, South Africa. No sampling strategy will be employed. The survey questionnaire will consist of demographic questions (consisting of six items) and vaccine confidence questions (comprising six items in Likert scale format). Log binomial models will be employed to identify factors associated with vaccine confidence and intention. The strength of association will be assessed using the OR and its 95% CI. Statistical significance will be defined at a p value <0.05. ETHICS AND DISSEMINATION: Ethics approval has been obtained for the study from Stellenbosch University (Human Research Ethics Committee reference number S19/01/014 (PhD)). The results will be shared with relevant health authorities, presented at conferences and published in a peer-reviewed journal.


Subject(s)
COVID-19 , Vaccines , COVID-19 Vaccines , Cross-Sectional Studies , Humans , SARS-CoV-2 , South Africa , Students , Vaccination
13.
Clin Infect Dis ; 72(2): 327-331, 2021 01 27.
Article in English | MEDLINE | ID: covidwho-1050126

ABSTRACT

The arrival of coronavirus disease 2019 (COVID-19) on the African continent resulted in a range of lockdown measures that curtailed the spread of the infection but caused economic hardship. African countries now face difficult choices regarding easing of lockdowns and sustaining effective public health control measures and surveillance. Pandemic control will require efficient community screening, testing, and contact tracing; behavioral change interventions; adequate resources; and well-supported, community-based teams of trained, protected personnel. We discuss COVID-19 control approaches in selected African countries and the need for shared, affordable, innovative methods to overcome challenges and minimize mortality. This crisis presents a unique opportunity to align COVID-19 services with those already in place for human immunodeficiency virus, tuberculosis, malaria, and non communicable diseases through mobilization of Africa's interprofessional healthcare workforce. By addressing the challenges, the detrimental effect of the COVID-19 pandemic on African citizens can be minimized.


Subject(s)
COVID-19 , Pandemics , Africa/epidemiology , Communicable Disease Control , Contact Tracing , Humans , Morbidity , SARS-CoV-2
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