Browsing by Author "Orienka Hellferscee"

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    A retrospective observational cohort study of the effect of antenatal influenza vaccination on birth outcomes in Cape Town South Africa 20152016
    Meredith McMorrow; Liza Rossi; Susan Meiring; Katherine Bishop; Sibongile Walaza; Orienka Hellferscee; Florette Treurnicht; Cheryl Cohen; E et al
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    Association of HIV Exposure and HIV Infection With Inhospital Mortality Among Hospitalized Infants 1 Year of Age South Africa 20162018
    Nicole Wolter; Sibongile Walaza; C von Mollendorf; Anne Von Gottberg; S Tempia; M McMorrow; Jocelyn Moyes; Florette Treurnicht; Orienka Hellferscee; Malefu Moleleki; Mvuyo Makhasi; N Baute; Cheryl Cohen
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    Detection of Victoria lineage influenza B viruses with K162 and N163 deletions in the hemagglutinin gene South Africa 2018
    Orienka Hellferscee; Florette Treurnicht; Lucinda Gaelejwe; aLEXANDRA mOERDYK; Gary Reubenson; Meredith McMorrow; Stefano Tempia; Johanna McAnerney; Sibongile Walaza; Nicole Wolter; Anne Von Gottberg; Cheryl Cohen
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    Epidemiology of Pertussis in Individuals of All Ages Hospitalized With Respiratory Illness in South Africa January 2013December 2018
    Nicole Wolter; Cheryl Cohen; Stefano Tempia; Sibongile Walaza; Fahima Moosa; Mignonette Du Plessis; Meredith L McMorrow; Florette Treurnicht; Orienka Hellferscee; Halima Dawood; Ebrahim Variava; Anne Von Gottberg
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    Human respiratory syncytial virus diversity and epidemiology among patients hospitalized with severe respiratory illness in South Africa, 2012–2015
    (2015) Ziyaad Valley-Omar; Stefano Tempia; Orienka Hellferscee; Sibongile Walaza; Ebrahim Variava6; Halima Dawood; Kathleen Kahn; Meredith McMorrow; Marthi Pretorius; Senzo Mtshali; Ernest Mamorobela; Nicole Wolter; Marietjie Venter; Anne von Gottberg; Cheryl Cohen; Florette K. Treurnicht
    Background: We aimed to describe the prevalence of human respiratory syncytial virus (HRSV) and evaluate associations between HRSV subgroups and/or genotypes and epidemiologic characteristics and clinical outcomes in patients hospitalized with severe respiratory illness (SRI). Methods: Between January 2012 and December 2015, we enrolled patients of all ages admitted to two South African hospitals with SRI in prospective hospital-based syndromic surveillance. We collected respiratory specimens and clinical and epidemiological data. Unconditional random effect multivariable logistic regression was used to assess factors associated with HRSV infection. Results: HRSV was detected in 11.2% (772/6908) of enrolled patients of which 47.0% (363/772) were under the age of 6 months. There were no differences in clinical outcomes of HRSV subgroup A-infected patients compared with HRSV subgroup B-infected patients but among patients aged <5 years, children with HRSV subgroup A were more likely be coinfected with Streptococcus pneumoniae (23/208 11.0% vs. 2/90, 2.0%; adjusted odds ratio 5.7). No significant associations of HRSV A genotypes NA1 and ON1 with specific clinical outcomes were observed. Conclusions: While HRSV subgroup and genotype dominance shifted between seasons, we showed similar genotype diversity as noted worldwide. We found no association between clinical outcomes and HRSV subgroups or genotypes.
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    Incidence and Transmission Dynamics of Bordetella pertussis Infection in Rural and Urban Communities, South Africa, 2016-2018
    (CENTERS DISEASE CONTROL) Fahima Moosa; Stefano Tempia; Jacoba Kleynhans; M McMorrow; Jocelyn Moyes; Mignonette Du Plessis; Maimuna Carrim; Florette Treurnicht; Orienka Hellferscee; T Mkhencele; A Mathunjwa; Neil Martinson; Kathleen Kahn; Limakatso Lebina; Floidy Wafawanaka; Cheryl Cohen; Anne Von Gottberg; Nicole Wolter
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    Mortality in children aged <5 years with severe acute respiratory illness in a high HIVprevalence urban and rural areas of South Africa, 2009–2013
    (2021-08-12) Oluwatosin A Ayeni; Sibongile Walaza; Stefano Tempia; Michelle Groome; Kathleen Kahn; Shabir A Madhi; Adam L Cohen; Jocelyn Moyes; Marietjie Venter; Marthi Pretorius; Florette Treurnicht; Orienka Hellferscee; Anne von Gottberg; Nicole Wolter; Cheryl Cohen
    Background: Severe acute respiratory illness (SARI) is an important cause of mortality in young children, especially in children living with HIV infection. Disparities in SARI death in children aged <5 years exist in urban and rural areas. Objective: To compare the factors associated with in-hospital death among children aged <5 years hospitalized with SARI in an urban vs. a rural setting in South Africa from 2009-2013. Methods: Data were collected from hospitalized children with SARI in one urban and two rural sentinel surveillance hospitals. Nasopharyngeal aspirates were tested for ten respiratory viruses and blood for pneumococcal DNA using polymerase chain reaction. We used multivariable logistic regression to identify patient and clinical characteristics associated with in-hospital death. Results: From 2009 through 2013, 5,297 children aged <5 years with SARI-associated hospital admission were enrolled; 3,811 (72%) in the urban and 1,486 (28%) in the rural hospitals. In-hospital case-fatality proportion (CFP) was higher in the rural hospitals (6.9%) than the urban hospital (1.3%, p<0.001), and among HIV-infected than the HIV-uninfected children (9.6% vs. 1.6%, p<0.001). In the urban hospital, HIV infection (odds ratio (OR):11.4, 95% confidence interval (CI):5.4-24.1) and presence of any other underlying illness (OR: 3.0, 95% CI: 1.0-9.2) were the only factors independently associated with death. In the rural hospitals, HIV infection (OR: 4.1, 95% CI: 2.3-7.1) and age <1 year (OR: 3.7, 95% CI: 1.9-7.2) were independently associated with death, whereas duration of hospitalization ≥5 days (OR: 0.5, 95% CI: 0.3-0.8) and any respiratory virus detection (OR: 0.4, 95% CI: 0.3-0.8) were negatively associated with death. Conclusion: We found that the case-fatality proportion was substantially higher among children admitted to rural hospitals and HIV infected children with SARI in South Africa. While efforts to prevent and treat HIV infections in children may reduce SARI deaths, further efforts to address health care inequality in rural populations are needed.
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    Rift Valley Fever Virus Seroprevalence among Humans Northern KwaZuluNatal Province South Africa 2018 2019
    Janusz Paweska; Veerle Msimang; Joe Kgaladi; Orienka Hellferscee; Jacqueline Weyer; Petrus Jansen van Vuren
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    The attributable fraction of respiratory syncytial virus among patients of different age with influenza-like illness and severe acute respiratory illness in a high HIV prevalence setting, South Africa, 2012-2016 Running title: The attributable fraction of RSV in South Africa (all ages), South Africa 2012- 2016
    (2022-11-22) Jocelyn Moyes; Stefano Tempia; Sibongile Walaza; Meredith L. McMorrow; Adam L. Cohen; Florette Treurnicht; Orienka Hellferscee; Nicole Wolter; Anne Von Gottberg; Halima Dawood; Ebrahim Variava; Kathleen Kahn; Shabir A. Madhi; Cheryl Cohen
    Introduction The detection of respiratory syncytial virus (RSV) in upper airway samples does not necessarily infer causality of illness. Calculating the attributable fraction (AF) of RSV in clinical syndromes could refine disease burden estimates. Methods Using unconditional logistic regression models, we estimated the AF of RSV-associated influenza-like illness (ILI) and severe-acute respiratory illness (SARI) cases by comparing RSVdetection prevalence among ILI and SARI cases to those of healthy controls in South Africa, 2012-2016. The analysis, stratified by HIV serostatus, was conducted in the age categories <1, 1-4, 5-24, 25-44, 45-64, ≥65 years. Results We included 12,048 individuals: 2,687 controls, 5,449 ILI cases and 5,449 SARI cases. RSVAFs for ILI were significant in <1, 1-4, 5-24, 25-44-year age groups: 84.9%(95% confidence interval (CI) 69.3%-92.6%), 74.6%(95%CI 53.6%-86.0%), 60.8%(95%CI 21.4%-80.5%) and 64.1%(95%CI 14.9%-84.9%), respectively. Similarly, significant RSV-AFs for SARI were 95.3%(95%CI 91.1%-97.5) and 83.4%(95%CI 70.9-90.5) in the <1 and 1-4-year age groups respectively. In HIV-infected persons, RSV was significantly associated with ILI cases versus controls in individuals aged 5-44 years. Conclusion High RSV-AFs in young children confirm RSV detection is associated severe respiratory illness in South African children, specifically infants. These estimates will assist with refining burden estimates and cost effectiveness models
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    Transient increased risk of influenza infection following RSV infection in South Africa findings from the PHIRST study South Africa 20162018
    (BIOMED CENTRAL LTD) N.R Waterlow; Jacoba Kleynhans; Nicole Wolter; Stefano Tempia; R.M Eggo; Orienka Hellferscee; Limakatso Lebina; Neil Martinson; Ryan Wagner; J Moyes; Anne Von Gottberg; Cheryl Cohen; S Flasche
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    Unmasking Pneumococcal Carriage in a High Human Immunodeficiency Virus (HIV) Prevalence Population in two Community Cohorts in South Africa, 2016–2018: The PHIRST Study
    (2022-07-19) Maimuna Carrim; Stefano Tempia; Deus Thindwa; Neil A Martinson; Kathleen Kahn; Stefan Flasche; Orienka Hellferscee; Florette K Treurnicht; Meredith L McMorrow; Jocelyn Moyes; Thulisa Mkhencele; Azwifarwi Mathunjwa; Jackie Kleynhans; Limakatso Lebina; Katlego Mothlaoleng; Floidy Wafawanaka; Francesc Xavier Gómez-Olivé; Cheryl Cohen; Anne von Gottberg; Nicole Wolter
    Background Longitudinal pneumococcus colonization data in high human immunodeficiency virus (HIV) prevalence settings following pneumococcal conjugate vaccine introduction are limited. Methods In 327 randomly selected households, 1684 individuals were enrolled and followed-up for 6 to 10 months during 2016 through 2018 from 2 communities. Nasopharyngeal swabs were collected twice weekly and tested for pneumococcus using quantitative lytA real-time polymerase chain reaction. A Markov model was fitted to the data to define the start and end of an episode of colonization. We assessed factors associated with colonization using logistic regression. Results During the study period, 98% (1655/1684) of participants were colonized with pneumococcus at least once. Younger age (<5 years: adjusted odds ratio [aOR], 14.1; 95% confidence [CI], 1.8–111.3, and 5–24 years: aOR, 4.8, 95% CI, 1.9–11.9, compared with 25–44 years) and HIV infection (aOR, 10.1; 95% CI, 1.3–77.1) were associated with increased odds of colonization. Children aged <5 years had fewer colonization episodes (median, 9) than individuals ≥5 years (median, 18; P < .001) but had a longer episode duration (<5 years: 35.5 days; interquartile range, 17–88) vs. ≥5 years: 5.5 days (4–12). High pneumococcal loads were associated with age (<1 year: aOR 25.4; 95% CI, 7.4–87.6; 1–4 years: aOR 13.5, 95% CI 8.3–22.9; 5–14 years: aOR 3.1, 95% CI, 2.1–4.4 vs. 45–65 year old patients) and HIV infection (aOR 1.7; 95% CI 1.2–2.4). Conclusions We observed high levels of pneumococcus colonization across all age groups. Children and people with HIV were more likely to be colonized and had higher pneumococcal loads. Carriage duration decreased with age highlighting that children remain important in pneumococcal transmission.