scholarly journals Asymptomatic Bordetella pertussis infections in a longitudinal cohort of young African infants and their mothers

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Christopher J Gill ◽  
Christian E Gunning ◽  
William B MacLeod ◽  
Lawrence Mwananyanda ◽  
Donald M Thea ◽  
...  
Keyword(s):  
Disease Surveillance ◽  
Full Range ◽  
Population Level ◽  
Pertussis Infection ◽  
Cross Sectional ◽  
Infectious Disease Surveillance ◽  
Longitudinal Cohort ◽  
High Incidence ◽  
Asymptomatic Infections ◽  
Pertussis Epidemiology

Recent pertussis resurgence in numerous countries may be driven by asymptomatic infections. Most pertussis surveillance studies are cross-sectional and cannot distinguish asymptomatic from pre-symptomatic infections. Longitudinal surveillance could overcome this barrier, providing more information about the true burden of pertussis at the population level. Here we analyze 17,442 nasopharyngeal samples from a longitudinal cohort of 1320 Zambian mother/infant pairs. Our analysis has two elements. First, we demonstrate that the full range of IS481 qPCR CT values provides insight into pertussis epidemiology, showing concordance of low and high CT results over time, within mother/infant pairs, and in relation to symptomatology. Second, we exploit these full-range qPCR data to demonstrate a high incidence of asymptomatic pertussis, including among infants. Our results demonstrate a wider burden of pertussis infection than we anticipated in this population, and expose key limitations of threshold-based interpretation of qPCR results in infectious disease surveillance.

scholarly journals Asymptomatic Bordetella pertussis infections in young African infants and their mothers identified within a longitudinal cohort

2020 ◽  
Author(s):  
CJ Gill ◽  
CE Gunning ◽  
W MacLeod ◽  
L Mwananyanda ◽  
D Thea ◽  
...  
Keyword(s):  
Full Range ◽  
Antibiotic Use ◽  
Full Cohort ◽  
Pertussis Infection ◽  
Cross Sectional ◽  
Vaccination Programs ◽  
Young Infants ◽  
Diagnostic Thresholds ◽  
Asymptomatic Infections ◽  
Pertussis Epidemiology

ABSTRACTDespite long-standing vaccination programs, pertussis incidence has increased in numerous countries; transmission by asymptomatic individuals is a suspected driver of this resurgence. However, unequivocal evidence documenting asymptomatic infections in adults and children is lacking due, in part, to the cross-sectional nature of most pertussis surveillance studies. In addition, modern pertussis surveillance relies on quantitative PCR (qPCR) using fixed diagnostic thresholds to identify cases.To address this gap, we present a longitudinal analysis of 17,442 nasopharyngeal samples collected from a cohort of 1,320 Zambian mother/infant pairs. Using full-range cycle threshold (CT) values from IS481 qPCR assays, we document widespread asymptomatic infections among mothers and also, surprisingly, among young infants. From an initial group of eight symptomatic infants who tested positive by qPCR, we identify frequent contemporaneous subclinical infections in mothers. Within the full cohort, we observe strong temporal correlation between low- and high-intensity qPCR signals. We compute a single time-averaged score for each individual summarizing the evidence for pertussis infection (EFI), and show that EFI strongly clusters within mother/infant pairs, and is strongly associated with clinical symptomatology and antibiotic use.Overall, the burden of pertussis here is substantially underestimated when restricting diagnostic criteria to IS481 CT≤35. Rather, we find that full-range CT values provide valuable insights into pertussis epidemiology in this population, and illuminate the infection arc within individuals. These findings have significant implications for quantifying asymptomatic pertussis prevalence and its contribution to overall transmission. Our results also expose limitations of threshold-based interpretations of qPCR assays in infectious disease surveillance.IMPORTANCE STATEMENTCurrent pertussis epidemiology rests largely on cross-sectional surveys that use diagnostic thresholds to interpret qPCR results as positive or negative, and thus fail to capture arcs of infection within individuals or populations. By longitudinally monitoring a cohort of African mother/infant pairs and using full-range qPCR results, we quantify the otherwise-hidden evidence for pertussis infection (EFI) in individuals. We demonstrate strong clustering of EFI within mother/infant pairs and quantify the association between EFI and both pertussis symptoms and antibiotic use. Critically, we find strong evidence that asymptomatic pertussis is common in both infants and mothers, indicating that the burden of pertussis has been significantly underestimated in this population. Our results also inform qPCR-based monitoring of other pathogens, such as SARS-CoV-2.

scholarly journals Seroprevalence of pertussis in adult population

2018 ◽  
Vol 146 (11-12) ◽  
pp. 641-645
Author(s):  
Vladimir Petrovic ◽  
Biljana Radosavljevic ◽  
Mioljub Ristic
Keyword(s):  
Adult Population ◽  
Age Groups ◽  
Cross Sectional Study ◽  
Pertussis Infection ◽  
Cross Sectional ◽  
Bordetella Pertussis Toxin ◽  
High Concentrations ◽  
Novi Sad ◽  
Induced Immunity ◽  
Pertussis Epidemiology

Introduction/Objective. Seroepidemiological studies are crucial for better understanding of pertussis epidemiology. The aim of this study was to assess the seroprevalence of anti-Bordetella pertussis toxin antibodies (anti-PT IgG) in the adult population of Novi Sad, and to evaluate the differences by age and sex. Methods. A cross-sectional study was conducted in 468 healthy adults aged ? 20 years stratified into seven age groups. The youngest of our participants received the last dose of the vaccine at least 18 years ago. Positive results of anti-PT IgG concentrations were considered a consequence of natural pertussis infection or reinfection. A commercial ELISA kit (EuroimmunR, Lubeck, Germany), with anti-PT IgG with four calibrators (5 IU/mL, 25 IU/mL, 100 IU/mL, and 200 IU/mL) was used. Results. Most of the subjects (53.8%) had anti-PT IgG of > 5 to < 62.5 IU/mL. The proportion of participants with high concentrations (62.5 to < 125 IU/mL) was statistically significantly higher in females than in males (5.4% vs. 0.4%, p = 0.002). The highest values of anti-PT IgG were detected among subjects in the age group of 20?24 years (17.5 ?} 22.2 IU/mL), and in the participants ? 60 years of age (15.0 ?} 29.4 IU/ mL). The percentage of anti-PT IgG concentration of ? 62.5 IU/mL was the highest among subjects aged ? 60 years (6.6%) and among those aged 20?24 years (5%). Conclusions. The limited duration of vaccine-induced immunity with subsequent infection or reinfection enables the circulation of pertussis in the adult population of Novi Sad that serves as the reservoir of infection for transmission to vulnerable persons.

scholarly journals Association of body pain and chronic disease: evidence from a 7-year population-based study in China

2021 ◽  
pp. rapm-2021-102700
Author(s):  
Yaxin Luo ◽  
Zheran Liu ◽  
Lianlian Yang ◽  
Juejin Li ◽  
Qiang Zhang ◽  
...  
Keyword(s):  
Chronic Disease ◽  
Chronic Diseases ◽  
Population Level ◽  
Chronic Respiratory Disease ◽  
Population Based ◽  
Cross Sectional ◽  
Longitudinal Cohort ◽  
Body Pain ◽  
Increased Risk ◽  
The Cross

BackgroundEvidence is limited on the risk impact of body pain on future chronic disease. The present study aimed to investigate the association between body pain and chronic diseases.MethodsData were analyzed using four waves of the China Health and Retirement Longitudinal Study with 17 708 individual respondents aged 45 years and older. The association between body pain and chronic disease was estimated in both a cross-sectional cohort (2011) and a longitudinal cohort (2011–2018). The key outcomes include the incidence of overall and any specific chronic diseases. The associations among different body pain sites and 10 independent chronic disease risks were also assessed.FindingsA total of 17 128 participants in 2011 were included in the cross-sectional cohort and 5611 participants were included in the 2011–2018 longitudinal cohort. Body pain showed an association with overall chronic disease in both the cross-sectional models (OR 2.71, 95% CI 2.47 to 2.98) and longitudinal model (risk ratio (RR) 1.21, 95% CI 1.07 to 1.35). Moreover, body pain was found to be associated with an increased risk of chronic respiratory disease (RR 1.43, 95% CI 1.06 to 1.92), heart disease (RR 1.45, 95% CI 1.12 to 1.89), kidney disease (RR 1.83, 95% CI 1.28 to 2.6), and digestive disease (RR 1.48, 95% CI 1.17 to 1.88).ConclusionBody pain is associated with major disease and mortality. Future clinical research should be targeted to whether or not improved pain control can mitigate this population-level disease burden.

General Cluster Sorption Isotherm

2020 ◽  
Author(s):  
Christoph Buttersack
Keyword(s):  
Density Functional ◽  
Capillary Condensation ◽  
Cluster Formation ◽  
Full Range ◽  
Full Description ◽  
Cross Sectional ◽  
Macroporous Silica ◽  
Isotherm Equation ◽  
Type Iv ◽  
Classical Thermodynamics

<p>Adsorption isotherms are an essential tool in chemical physics of surfaces. However, several approaches based on a different theoretical basis exist and for isotherms including capillary condensation existing approaches can fail. Here, a general isotherm equation is derived and applied to literature data both concerning type IV isotherms of argon and nitrogen in ordered mesoporous silica, and type II isotherms of disordered macroporous silica. The new isotherm covers the full range of partial pressure (10<sup>-6</sup> - 0.7). It relies firstly on the classical thermodynamics of cluster formation, secondly on a relationship defining the free energy during the increase of the cluster size. That equation replaces the Lennard-Jones potentials used in the classical density functional theory. The determination of surface areas is not possible by this isotherm because the cross-sectional area of a cluster is unknown. Based on the full description of type IV isotherms, most known isotherms are accessible by respective simplifications. </p>

Asymptomatic low-density Plasmodium infection during non-transmission season: a community-based cross-sectional study in two districts of North Eastern Region, India

2021 ◽  
Author(s):  
Hari Shankar ◽  
Sobhan Phookan ◽  
Mrigendra Pal Singh ◽  
Ram Suresh Bharti ◽  
Naseem Ahmed ◽  
...  
Keyword(s):  
Cross Sectional Study ◽  
Diagnostic Tools ◽  
Eastern Region ◽  
Low Density ◽  
Plasmodium Infection ◽  
Sectional Study ◽  
Cross Sectional ◽  
Health Agencies ◽  
North Eastern ◽  
Asymptomatic Infections

Abstract Background Malaria elimination requires targeting asymptomatic and low-density Plasmodium infections that largely remain undetected. Therefore we conducted a cross-sectional study to estimate the burden of asymptomatic and low-density Plasmodium infection using conventional and molecular diagnostics. Methods A total of 9118 participants, irrespective of age and sex, were screened for malaria using rapid diagnostic tests (RDTs), microscopy and polymerase chain reaction. Results Among the participants, 707 presented with symptoms and 8411 without symptoms, of which Plasmodium was present in 15.6% (110/707) and 8.1% (681/8411), respectively. Low-density infection was found in 5.1% (145/2818) of participants and 8327 of 9118 were Plasmodium negative. Endemicity was propotional to asymptomatic infections (high endemicity 11.1% [404/3633] vs low endemicity 5.8% [277/4778]; odds ratio [OR] 2.0 [95% confidence interval {CI} 1.7 to 2.4]) but inversely related to low-density infection (high endemicity 3.7% [57/1545] vs low endemicity 6.9% [88/1273]; OR 1.9 [95% CI 1.4 to 2.7]). The spleen rate in children 2–9 y of age was 17.9% (602/3368) and the enlarged spleen index was 1.6. Children between 8 and 14 y showed higher odds for asymptomatic (adjusted OR [aOR] 1.75 [95% CI 1.4 to 2.2]) and low-density infections (aOR 0.63 [95% CI 0.4 to 1.0)] than adults. Conclusions The prevalence of asymptomatic and low-density Plasmodium infection undermines the usefulness of standard diagnostic tools used by health agencies. This necessitates deploying molecular tools in areas where malaria microscopy/RDTs indicate a dearth of infection.

scholarly journals Modeling Hearing Loss Progression and Asymmetry in the Older Old: A National Population-Based Survey

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 214-215
Author(s):  
Rahul Sharma ◽  
Anil Lalwani ◽  
Justin Golub
Keyword(s):  
Hearing Loss ◽  
Pure Tone ◽  
Population Level ◽  
Population Based ◽  
National Database ◽  
Cross Sectional ◽  
Adult Lifespan ◽  
Pure Tone Average ◽  
Age Related ◽  
Public Datasets

Abstract The progression and asymmetry of age-related hearing loss has not been well characterized in those 80 years of age and older because public datasets mask upper extremes of age to protect anonymity. We aimed to model the progression and asymmetry of hearing loss in the older old using a representative, national database. This was a cross-sectional, multicentered US epidemiologic analysis using the National Health and Nutrition Examination Study (NHANES) 2005-2006, 2009-2010, and 2011-2012 cycles. Subjects included non-institutionalized, civilian adults 80 years and older (n=621). Federal security clearance was granted to access publicly-restricted age data. Outcome measures included pure-tone average air conduction thresholds and the 4-frequency pure tone average (PTA). 621 subjects were 80 years old or older (mean=84.2 years, range=80-104 years), representing 10,600,197 Americans. Hearing loss exhibited constant acceleration across the adult lifespan at a rate of 0.0052 dB/year2 (95% CI = 0.0049, 0.0055). Compounded over a lifetime, the velocity of hearing loss would increase five-fold, from 0.2 dB loss/year at age 20 to 1 dB loss/year at age 100. This model predicted mean PTA within 2 dB of accuracy for most ages between 20 and 100 years. There was no change in the asymmetry of hearing loss with increasing age over 80 years (linear regression coefficient of asymmetry over age=0.07 (95% CI=-0.01, 0.24). In conclusion, hearing loss steadily and predictably accelerates across the adult lifespan to at least age 100, becoming near-universal. These population-level statistics will guide treatment and policy recommendations for hearing health in the older old.

scholarly journals Recall of government healthy eating campaigns by consumers in five countries

2021 ◽  
pp. 1-31
Author(s):  
Samantha Goodman ◽  
Gabriela Armendariz ◽  
Adele Corkum ◽  
Laura Arellano ◽  
Alejandra Jáuregui ◽  
...  
Keyword(s):  
Healthy Eating ◽  
Fruits And Vegetables ◽  
Food Policy ◽  
Logistic Models ◽  
Population Level ◽  
Policy Study ◽  
Cross Sectional ◽  
Sugary Drinks ◽  
Income Adequacy ◽  
Low Education

ABSTRACT Objective: To examine awareness and recall of healthy eating public education campaigns in five countries. Design: Data were cross-sectional and collected as part of the 2018 International Food Policy Study. Respondents were asked whether they had seen government healthy eating campaigns in the past year; if yes (awareness), they were asked to describe the campaign. Open-ended descriptions were coded to indicate recall of specific campaigns. Logistic models regressed awareness of healthy eating campaigns on participant country, age, sex, ethnicity, education, income adequacy and BMI. Analyses were also stratified by country. Setting: Online surveys. Participants: Participants were Nielsen panelists aged ≥18 years in Australia, Canada, Mexico, UK and US (n=22,463). Results: Odds of campaign awareness were higher in Mexico (50.9%) than UK (18.2%), Australia (17.9%), US (13.0%) and Canada (10.2%) (P<0.001). Awareness was also higher in UK and Australia versus Canada and US, and US versus Canada (P<0.001). Overall, awareness was higher among males versus females and respondents with medium or high versus low education (P<0.001 for all). Similar results were found in stratified models, although no sex difference was observed in Australia or UK (P>0.05), and age was associated with campaign awareness in UK (P<0.001). Common key words in all countries included sugar/sugary drinks, fruits and vegetables, and physical activity. The top five campaigns recalled were Chécate, mídete, muévete (Mexico), PrevenIMSS (Mexico), Change4Life (UK), LiveLighter® (Australia), and Actívate, Vive Mejor (Mexico). Conclusions: In Mexico, UK and Australia, comprehensive campaigns to promote healthy lifestyles appear to have achieved broad, population-level reach.

scholarly journals Phylogenomics reveals viral sources, transmission, and potential superinfection in early-stage COVID-19 patients in Ontario, Canada

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Calvin P. Sjaarda ◽  
Nazneen Rustom ◽  
Gerald A. Evans ◽  
David Huang ◽  
Santiago Perez-Patrigeon ◽  
...  
Keyword(s):  
Phylogenetic Analysis ◽  
Disease Surveillance ◽  
Early Stage ◽  
Emerging Diseases ◽  
Contact Tracing ◽  
Travel History ◽  
Infectious Disease Surveillance ◽  
Viral Genomes ◽  
Heterozygous Variant ◽  
Sequencing Platforms

AbstractThe emergence and rapid global spread of SARS-CoV-2 demonstrates the importance of infectious disease surveillance, particularly during the early stages. Viral genomes can provide key insights into transmission chains and pathogenicity. Nasopharyngeal swabs were obtained from thirty-two of the first SARS-CoV-2 positive cases (March 18–30) in Kingston Ontario, Canada. Viral genomes were sequenced using Ion Torrent (n = 24) and MinION (n = 27) sequencing platforms. SARS-CoV-2 genomes carried forty-six polymorphic sites including two missense and three synonymous variants in the spike protein gene. The D614G point mutation was the predominate viral strain in our cohort (92.6%). A heterozygous variant (C9994A) was detected by both sequencing platforms but filtered by the ARTIC network bioinformatic pipeline suggesting that heterozygous variants may be underreported in the SARS-CoV-2 literature. Phylogenetic analysis with 87,738 genomes in the GISAID database identified global origins and transmission events including multiple, international introductions as well as community spread. Reported travel history validated viral introduction and transmission inferred by phylogenetic analysis. Molecular epidemiology and evolutionary phylogenetics may complement contact tracing and help reconstruct transmission chains of emerging diseases. Earlier detection and screening in this way could improve the effectiveness of regional public health interventions to limit future pandemics.

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