97 research outputs found
Is the use of hormonal contraception a risk factor for incident sexually transmitted infections in a cohort of women aged 18 to 35 in Soweto, South Africa?
MSc (Med), Epidemiology and Biostatistics, University of the WitwatersrandIntroduction
This secondary data analysis of a prospective cohort study set out to describe the
association between the use of hormonal contraception and sexually transmitted
infection (STI) acquisition in a cohort of 752 HIV negative women who were followed
up for a year.
Methods
Outcome variables were measured by standard laboratory tests (PCR for Chlamydia
trachomatis (CT) and Neiserria gonorrhoea (NG), culture for Trichomonas vaginalis
(TV) and gram stain with Nugent score for Bacterial Vaginosis (BV). Exposure
variable information was collected by structured interview. Basic descriptive
statistics were applied to describe the characteristics of the cohort, including a
comparison of women who used contraception and those who did not. A time series
analysis including incidence rates for the outcomes (CT, NG, TV and BV), Kaplan
Meier curves for time to event measurement and Cox regression models (univariate
and multivariate), for the estimation of risk were applied.
Results
The analysis found no significant difference between women who use hormonal
contraception and those who did not with respect to baseline demographic
characteristics. Incidence rates per 100 women years to follow up with 95%
confidence intervals were: CT 13 (7 to 17), NG 2 (1 to 4), TV 6 (4 to10), BV 72 (63 to
83). Kaplan Meier curves showed no significant difference in time to event between women who used contraception and those who did not. Adjusted hazard ratios for
women who used contraception was 1.12 (0.69 to1.82) for CT, 0.47 (0.17 to 1.30)
for NG, 1.06 (0.48 to 2.34) for TV and 0.27 (0.05 to 1.52) for BV.
Conclusion
This analysis did not reveal any significant associations between the use of
hormonal contraception and the acquisition of STIs, however the trends in risks
follow those reported in the literature
Comparison of focus HerpesSelect and Kalon HSV-2 gG2 ELISA serological assays to detect herpes simplex virus type 2 antibodies in a South African population.
INTRODUCTION: Sero-epidemiological studies of herpes simplex virus (HSV) type 2 infection in Africa remain difficult to interpret as a result of the high rate of false-positive results observed when using the new recombinant gG2 HSV-2 ELISA tests. The performance of two widely used gG2 ELISA was compared to derive an appropriate testing algorithm for use in South Africa. METHODS: Sera from 210 women attending family planning clinics in Johannesburg were tested using HerpeSelect and Kalon HSV-2 gG2 assays. Sera from 20 discordant pairs, 44 concordant positive and 33 concordant negative samples were further tested by HSV Western blot. The sensitivity and specificity of each test and of combination algorithms compared with Western blot were calculated. RESULTS: HerpeSelect had a sensitivity of 98% (95% CI 95 to 100) and specificity of 61% (95% CI 48 to 74). Kalon was less sensitive (89%, 95% CI 83 to 94) but more specific (85%, 95% CI 61 to 100). Seroprevalence may have been overestimated by as much as 14% by HerpeSelect. Specificity was improved by raising the cut-off index for the determination of a positive result for HerpeSelect (to >or=3.5), but not for Kalon. HIV-1 infection reduced the specificity of HerpeSelect to 30%. Improved sensitivity and specificity were obtained by a two-test algorithm using HerpeSelect (>or=3.5) as the first test and Kalon to resolve equivocal results (sensitivity 92%, 95% CI 82 to 98; specificity 91%, 95% CI 79 to 98). CONCLUSION: Newer HSV-2 serological tests have low specificity in this South African population with a high HIV-1 prevalence. Two-step testing strategies could provide rational testing alternatives to Western blot
Approaches to use the WHO respiratory syncytial virus surveillance platform to estimate disease burden
The World Health Organization (WHO) recently completed the first phase of a RSV surveillance pilot study in fourteen countries (two to three in each WHO region) building on the Global Influenza Surveillance and Response System (GISRS). This active surveillance strategy had several objectives including understanding RSV-related health burden in a variety of settings. A range of approaches can be used to estimate disease burden; most approaches could not be applied by participating countries in the WHO surveillance pilot. This article provides the recommendations made by WHO for strengthening and expanding the scope of the RSV surveillance in the next phase to enable burden estimation
Global respiratory syncytial virus-associated mortality in young children (RSV GOLD): a retrospective case series
Background: Respiratory syncytial virus (RSV) infection is an important cause of pneumonia mortality in young children. However, clinical data for fatal RSV infection are scarce. We aimed to identify clinical and socioeconomic characteristics of children aged younger than 5 years with RSV-related mortality using individual patient data.
Methods: In this retrospective case series, we developed an online questionnaire to obtain individual patient data for clinical and socioeconomic characteristics of children aged younger than 5 years who died with community-acquired RSV infection between Jan 1, 1995, and Oct 31, 2015, through leading research groups for child pneumonia identified through a comprehensive literature search and existing research networks. For the literature search, we searched PubMed for articles published up to Feb 3, 2015, using the key terms “RSV”, “respiratory syncytial virus”, or “respiratory syncytial viral” combined with “mortality”, “fatality”, “death”, “died”, “deaths”, or “CFR” for articles published in English. We invited researchers and clinicians identified to participate between Nov 1, 2014, and Oct 31, 2015. We calculated descriptive statistics for all variables.
Findings: We studied 358 children with RSV-related in-hospital death from 23 countries across the world, with data contributed from 31 research groups. 117 (33%) children were from low-income or lower middle-income countries, 77 (22%) were from upper middle-income countries, and 164 (46%) were from high-income countries. 190 (53%) were male. Data for comorbidities were missing for some children in low-income and middle-income countries. Available data showed that comorbidities were present in at least 33 (28%) children from low-income or lower middle-income countries, 36 (47%) from upper middle-income countries, and 114 (70%) from high-income countries. Median age for RSV-related deaths was 5·0 months (IQR 2·3–11·0) in low-income or lower middle-income countries, 4·0 months (2·0–10·0) in upper middle-income countries, and 7·0 months (3·6–16·8) in high-income countries.
Interpretation: This study is the first large case series of children who died with community-acquired RSV infection. A substantial proportion of children with RSV-related death had comorbidities. Our results show that perinatal immunisation strategies for children aged younger than 6 months could have a substantial impact on RSV-related child mortality in low-income and middle-income countries
The cost-effectiveness of trivalent and quadrivalent influenza vaccination in communities in South Africa, Vietnam and Australia
BACKGROUND: To inform national healthcare authorities whether quadrivalent influenza vaccines (QIVs) provide better value for money than trivalent influenza vaccines (TIVs), we assessed the cost-effectiveness of TIV and QIV in low-and-middle income communities based in South Africa and Vietnam and contrasted these findings with those from a high-income community in Australia. METHODS: Individual based dynamic simulation models were interfaced with a health economic analysis model to estimate the cost-effectiveness of vaccinating 15% of the population with QIV or TIV in each community over the period 2003-2013. Vaccination was prioritized for HIV-infected individuals, before elderly aged 65+ years and young children. Country or region-specific data on influenza-strain circulation, clinical outcomes and costs were obtained from published sources. The societal perspective was used and outcomes were expressed in International) per quality-adjusted life-year (QALY) gained. RESULTS: When compared with TIV, we found that QIV would provide a greater reduction in influenza-related morbidity in communities in South Africa and Vietnam as compared with Australia. The incremental cost-effectiveness ratio of QIV versus TIV was estimated at I1505/QALY in Vietnam and I$80,966/QALY in Australia. CONCLUSIONS: The cost-effectiveness of QIV varied between communities due to differences in influenza epidemiology, comorbidities, and unit costs. Whether TIV or QIV is the most cost-effective alternative heavily depends on influenza B burden among subpopulations targeted forvaccination in addition to country-specific willingness-to-pay thresholds and budgetary impact
Modeling the impact of COVID-19 nonpharmaceutical interventions on respiratory syncytial virus transmission in South Africa
Background: The South African government employed various nonpharmaceutical interventions (NPIs) to reduce the spread of SARS-CoV-2. Surveillance data from South Africa indicates reduced circulation of respiratory syncytial virus (RSV) throughout the 2020–2021 seasons. Here, we use a mechanistic transmission model to project the rebound of RSV in the two subsequent seasons. Methods: We fit an age-structured epidemiological model to hospitalization data from national RSV surveillance in South Africa, allowing for time-varying reduction in RSV transmission during periods of COVID-19 circulation. We apply the model to project the rebound of RSV in the 2022 and 2023 seasons. Results: We projected an early and intense outbreak of RSV in April 2022, with an age shift to older infants (6–23 months old) experiencing a larger portion of severe disease burden than typical. In March 2022, government alerts were issued to prepare the hospital system for this potentially intense outbreak. We then assess the 2022 predictions and project the 2023 season. Model predictions for 2023 indicate that RSV activity has not fully returned to normal, with a projected early and moderately intense wave. We estimate that NPIs reduced RSV transmission between 15% and 50% during periods of COVID-19 circulation. Conclusions: A wide range of NPIs impacted the dynamics of the RSV outbreaks throughout 2020–2023 in regard to timing, magnitude, and age structure, with important implications in a low- and middle-income countries (LMICs) setting where RSV interventions remain limited. More efforts should focus on adapting RSV models to LMIC data to project the impact of upcoming medical interventions for this disease.</p
Impact of subgroup distribution on seasonality of human respiratory syncytial virus:A global systematic analysis
Background
Previous studies reported inconsistent findings regarding the association between respiratory syncytial virus (RSV) subgroup distribution and timing of RSV season. We aimed to further understand the association by conducting a global-level systematic analysis.
Methods
We compiled published data on RSV seasonality through a systematic literature review, and unpublished data shared by international collaborators. Using annual cumulative proportion (ACP) of RSV-positive cases, we defined RSV season onset and offset as ACP reaching 10% and 90%, respectively. Linear regression models accounting for meteorological factors were constructed to analyze the association of proportion of RSV-A with the corresponding RSV season onset and offset.
Results
We included 36 study sites from 20 countries, providing data for 179 study-years in 1995–2019. Globally, RSV subgroup distribution was not significantly associated with RSV season onset or offset globally, except for RSV season offset in the tropics in 1 model, possibly by chance. Models that included RSV subgroup distribution and meteorological factors explained only 2%–4% of the variations in timing of RSV season.
Conclusions
Year-on-year variations in RSV season onset and offset are not well explained by RSV subgroup distribution or meteorological factors. Factors including population susceptibility, mobility, and viral interference should be examined in future studies
Origine sociale et comportement politique
Les conséquences politiques de la mobilité sociale intergénérationnelle sur les comportements et les attitudes politiques des individus ont fait l'objet, depuis une vingtaine d'années, d'une série de recherches en particulier aux Etats-Unis et en Angleterre. A la suite de ces travaux une conclusion majeure semble s'imposer : les « mobiles sociaux » adopteraient un comportement politique intermédiaire entre leur groupe d'origine et leur groupe d'arrivée. Dans cette recherche, qui se fonde sur l'analyse d'un échantillon représentatif de cadres moyens et supérieurs, l'origine sociale paraît effectivement déterminer pour partie les comportements et attitudes politiques des individus appartenant aux couches moyennes salariées. Toutefois, une étude plus précise de ce mécanisme montre que l'effet de l'origine sociale sur le comportement et les attitudes politiques n'est pas seulement fonction de la distance entre la position sociale du père et celle du fils mais se diversifie également selon la nature et les conditions du trajet social effectué par l'individu.The political consequences of intergenerational social mobility on individuals' political attitudes and
behavior have been studied in a series of inquiries over the past twenty years, especially in the United
States and England. As a result of this work, it seems that one major conclusion may be drawn: the
"socially mobile" seem to adopt a political behavior which is intermediate to that of the group from which
they started out and that into which they are arriving. In this study based on a representative sample of
middle — and upper — level executives, social origin indeed seems to be in part a determining factor in
the political behavior and attitudes of individuals belonging to the middle range of the wage scale.
However, a closer study of this mechanism shows that the effect of social origin upon political behavior
and attitudes is not only a function of the distance between the father's and the son's social positions,
but also differs according to the nature and conditions of the individual's social ascension
The role of influenza, RSV and other common respiratory viruses in severe acute respiratory infections and influenza-like illness in a population with a high HIV sero-prevalence, South Africa, 2012-2015
BACKGROUND : Viruses detected in patients with acute respiratory infections may be the
cause of illness or colonizers.
METHODS : We compared the prevalence of 10 common respiratory viruses (influenza A
and B viruses, parainfluenza virus 1, 2, and 3; respiratory syncytial virus (RSV);
adenovirus, rhinovirus, human metapneumovirus (hMPV) and enterovirus) in patients
hospitalized with severe acute respiratory illness (SARI), outpatients with influenza-like
illness (ILI), and control subjects who did not report any febrile, respiratory or
gastrointestinal illness during 2012-2015 in South Africa. We estimated the attributable
fraction (AF) and the detection rate attributable to illness for each of the different
respiratory viruses. RESULTS : We enrolled 1959 SARI, 3784 ILI and 1793 controls. Influenza virus (AF:
86.3%; 95%CI: 77.7%-91.6%), hMPV (AF: 85.6%%; 95%CI: 72.0%-92.6%), and RSV
(AF: 83.7%; 95%CI: 77.5%-88.2%) infections were highly associated with severe
disease, while rhinovirus (AF: 46.9%; 95%CI: 37.6%-56.5%) and adenovirus (AF:
36.4%; 95%CI: 20.6%-49.0%) were only moderately associated. The estimated
detection rate associated with severe disease was: 20.2% for rhinovirus, 16.7% for
RSV, 7.0% for adenovirus, 4.9% for influenza virus and 3.8% for hMPV. Similar
patterns were observed for patients with ILI. CONCLUSIONS : Influenza, RSV and hMPV can be considered likely pathogens if
detected in patients with ILI and SARI while rhinovirus and adenovirus were commonly
identified also among controls suggesting that they may cause only a proportion of
clinical disease observed in positive patients. Nonetheless, given their high estimated
detection rate attributable to illness, they may be important contributors to disease.Co-operative agreement 5U51/IP000155 with the Centers for Disease Control and Prevention, Atlanta, Georgia, USA.http://www.elsevier.com/locate/jcv2017-02-28hb2016Medical Virolog
Changes in the global hospitalisation burden of respiratory syncytial virus in young children during the COVID-19 pandemic: a systematic analysis
Background The coronavirus disease 2019 (COVID-19) pandemic was reported to have impacted RSV epidemiology and could have important implications for RSV prevention and control strategies. We aimed to understand the RSV-associated acute lower respiratory infection (ALRI) hospitalisation burden in children younger than five years during the COVID-19 pandemic period and the possible changes in RSV epidemiology from a global perspective.Methods We conducted a systematic literature search for studies published between January 1, 2020 and June 30, 2022, from MEDLINE (Ovid), Embase (Ovid), Global Health (Ovid), Web of Science, WHO COVID-19 database, CINAHL, LILACS, OpenGrey, CNKI, WanFang and ChongqingVIP. We included unpublished RSV epidemiology data shared by international collaborators. Eligible studies reported data for RSV-associated ALRI hospital admission rates or at least one of the following severity measures: the proportion of RSV cases that needed supplemental oxygen, mechanical ventilation or intensive care unit admission, and in-hospital case fatality ratio. A generalised linear mixed-effects model was used for data synthesis to understand the changes in the incidence, age distribution and severity of RSV-associated ALRI hospitalisations in children under five years during the COVID-19 pandemic, compared to the year 2019. Findings We included 61 studies, 14 studies from published literature and 47 unpublished datasets. Most studies (51/61) were from the high-income region, followed by the upper-middle-income region (9/61); only one study was from the lower-middle-income region, and no studies were from the low-income region. Compared to 2019, all income regions saw substantial decreases in RSV-associated ALRI hospitalisation rate across all age groups in 2020; the number of RSV-associated ALRI hospitalisations in children aged 0–<60 months decreased by approximately 80% (325,000 to 66,000), 14% (581,000 to 501,000) and 42% (1,378,000 to 795,000) for high-income, upper-middle-income and lower-middle-income countries, respectively. RSV hospitalisation rate started to rise in 2021, and by March 2022, the annualised rate returned to a level comparable to 2019 (6·0/1000, 95% uncertainty interval [UI] 5·4–6·8 by March 2022 vs 5·0/1000, 3·6–6·8 in 2019) in high-income countries while remaining lower in middle-income countries. Across all time periods and income regions, RSV-associated ALRI hospitalisation rates peaked in infants aged 0–<3 months and declined with increasing age. Compared to the pre-pandemic period, there was a significantly increased proportion of RSV-associated ALRI hospitalisations in those aged 12–<24 months in high-income and upper-middle-income regions (ORs ranged from 1·30 [1·07–1·59] to 2·05 [1·66–2·54]). No consistent changes in disease severity were observed. Interpretation Our study documented a significant reduction in RSV-associated ALRI hospitalisation burden in children under five years during the first year of the COVID-19 pandemic. A rebound to pre-pandemic levels in RSV-associated ALRI hospitalisation rate was observed in the high-income region by March 2022 but not in the middle-income region, suggesting a more persistent negative impact of the COVID-19 pandemic on health-care systems and health-care access in middle-income regions. RSV surveillance needs to be established (or re-established) to monitor the changes in RSV epidemiology, particularly in low- and lower-middle-income countries.Funding EU Innovative Medicines Initiative Preparing for RSV Immunisation and Surveillance in Europe (PROMISE); Bill & Melinda Gates Foundation; World Health Organization. <br/
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