scholarly journals 1146Assessing the uncertainty around age-mixing patterns in HIV transmission inferred from phylogenetic trees

2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Peter Nyasulu
Keyword(s):  
Phylogenetic Trees ◽  
Hiv Transmission ◽  
Age Difference ◽  
Transmission Network ◽  
Age Group ◽  
Younger Women ◽  
Prevention Interventions ◽  
Younger Men ◽  
Mixing Patterns ◽  
Set Up

Abstract Introduction Understand age-mixing patterns in HIV transmission is a key to design and implement HIV prevention interventions. As such, the use of phylogenetic tree seems promising since this approach is based on data from a transmission network. Methods Through a simulation study, we used transmission clusters computed from phylogenetic trees to investigate age-mixing patterns. From transmission clusters, we estimated a transmission network using pairings. We inferred measurements, which depict age-mixing patterns in transmission i.e. ‘proportions of men/women of a certain age-group paired with women/men of another age-group’, and mean, median, and standard deviation of average age difference between women/men with their respective pairs. We investigated the uncertainty around these measurements as a function of sampling coverage in different sequence missingness scenarios. Results According to the simulation set-up of age mixing in partnership, there are relationships, which are less likely and others highly likely. Explicitly, partnerships between younger men (<25 years) and older women (25 to 50 years) are less likely to happen in the sexual network, whereas partnership between younger women (<25 years) and older men (25 to 50 years) are more likely to happen as are age group relationship having intermediate magnitude in partnership. Conclusion Transmission clusters allow us to strive with more improved information regarding cross-generation transmission. It enables us to understand the importance of age mixing beyond describing the mean age difference, and that one needs to consider the variation of age differences between pairs of individuals as well as among the partners of a given individual.

scholarly journals Assessing the uncertainty around age-mixing patterns in HIV transmission inferred from phylogenetic trees

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0249013
Author(s):  
David Niyukuri ◽  
Peter Nyasulu ◽  
Wim Delva
Keyword(s):  
Phylogenetic Trees ◽  
Hiv Transmission ◽  
Sequence Data ◽  
Age Groups ◽  
Sampling Strategy ◽  
Sub Saharan Africa ◽  
Age Difference ◽  
Men And Women ◽  
Hiv Prevention Strategies ◽  
Mixing Patterns

Understanding age-mixing patterns in Human Immunodeficiency Virus (HIV) transmission networks can enhance the design and implementation of HIV prevention strategies in sub-Saharan Africa. Due to ethical consideration, it is less likely possible to conduct a benchmark study to assess which sampling strategy, and sub-optimal sampling coverage which can yield best estimates for these patterns. We conducted a simulation study, using phylogenetic trees to infer estimates of age-mixing patterns in HIV transmission, through the computation of proportions of pairings between men and women, who were phylogenetically linked across different age groups (15–24 years, 25–39 years, and 40–49 years); and the means, and standard deviations of their age difference. We investigated also the uncertainty around these estimates as a function of the sampling coverage in four sampling strategies: when missing sequence data were missing completely at random (MCAR), and missing at random (MAR) with at most 30%—50%—70% of women in different age groups being in the sample. The results suggested that age-mixing patterns in HIV transmission can be unveiled from proportions of phylogenetic pairings between men and women across age groups; and the mean, and standard deviation of their age difference. A 55% sampling coverage was sufficient to provide the best values of estimates of age-mixing patterns in HIV transmission with MCAR scenario. But we should be cautious in interpreting proportions of men phylogenetically linked to women because they may be overestimated or underestimated, even at higher sampling coverage. The findings showed that, MCAR was the best sampling strategy. This means, it is advisable not to use sequence data collected in settings where we can find a systematic imbalance of age and gender to investigate age-mixing in HIV transmission. If not possible, ensure to take into consideration the imbalance in interpreting the results.

Choosing a book by its cover: analysis of a reader’s choice

2018 ◽  
Vol 74 (2) ◽  
pp. 430-446 ◽  
Author(s):  
Arūnas Gudinavičius ◽  
Andrius Šuminas
Keyword(s):  
Research Question ◽  
Age Groups ◽  
Age Group ◽  
Content Type ◽  
Younger Women ◽  
Book Choice ◽  
Massive Growth ◽  
The Difference ◽  
Set Up ◽  
Women’S Preferences

Purpose The massive growth in the number of book titles has made publishers think about how to attract a customer’s attention to particular books. This is the reason why the book cover plays an important role as a tool of communication with the reader. The research question of this exploratory study is whether the preference given by readers to book cover colors is different across genders and age groups when they choose the book in an online bookstore by its cover. The paper aims to discuss these issues. Design/methodology/approach The experiment in a bookstore and a library was done. Each respondent was asked to choose one book from our sample of 18 books and a mobile eye tracking laboratory was set up in order to find out the respondents’ basic gazing data. After conducting an experiment with bookstore and library visitors, the results showed that younger women tend to select a book by its cover (when the time for selection is not limited) statistically significantly faster than men of the same age group. The difference disappears with age. Findings The data of the experiment suggested that women from the age group 18-35 prefer books with cool color covers and the preference disappears with age; accordingly, men in the age group 56+ prefer books with warm color covers. The preference was not seen in younger age groups. The analysis of data on the number of choices for each cover and the time spent looking at each of them revealed a significant positive correlation between the women’s preferences in selecting covers and the time women spend looking at them; however, there was no such correlation in the case of men’s data. Originality/value The study has shown that the reader’s book choice is at least partly influenced by the cover color. The preference given to cool and warm colors and the speed of decision making show certain differences across genders and age groups. The result contributes to knowing how to create book covers more adopted to reader’s needs.

scholarly journals Factors associated with phylogenetic clustering of hepatitis C among people who inject drugs in Baltimore

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Oluwaseun Falade-Nwulia ◽  
Jada Hackman ◽  
Shruti H. Mehta ◽  
Sean D. McCormick ◽  
Gregory D. Kirk ◽  
...  
Keyword(s):  
Hepatitis C ◽  
Hiv Infection ◽  
Phylogenetic Trees ◽  
People Who Inject Drugs ◽  
Hcv Infection ◽  
Age Difference ◽  
Factors Associated ◽  
Female Sex ◽  
Prevention Interventions ◽  
Direct Acting

Abstract Background The availability of effective, oral direct acting antivirals (DAAs) for hepatitis C virus (HCV) treatment has put elimination of HCV as a public health challenge within reach. However, little is known about the characteristics of transmission networks of people who inject drugs (PWID). Methods Sequencing of a segment of the HCV genome was performed on samples collected from a community-based cohort of PWID between August 2005 and December 2016. Phylogenetic trees were inferred, and clusters were identified (70% bootstrap threshold; 0.04 maximum genetic distance threshold). We describe sex, race, age difference, and HIV infection status of potential transmission partners. Logistic regression was used to assess factors associated with being in an HCV cluster. Results Of 508 HCV genotype 1 viremic PWID, 8% (n = 41) were grouped into 20 clusters, consisting of 19 pairs and 1 triad. In adjusted analyses, female sex (odds ratio [OR] 2.3 [95% confidence interval (CI) 1.2–4.5]) and HIV infection (OR 5.7 [CI 2.7–11.9]) remained independently associated with being in an HCV infection cluster. Conclusions Molecular epidemiological analysis reveals that, in this cohort of PWID in Baltimore, HIV infection and female sex were associated with HCV clustering. Combination HCV prevention interventions targeting HIV infected PWID and addressing HCV infection prevention needs of women have potential to advance HCV elimination efforts.

scholarly journals Inferring the age difference in HIV transmission pairs by applying phylogenetic methods on the HIV transmission network of the Swiss HIV Cohort Study

2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Katharina Kusejko ◽  
Claus Kadelka ◽  
Alex Marzel ◽  
Manuel Battegay ◽  
Enos Bernasconi ◽  
...  
Keyword(s):  
Cohort Study ◽  
Hiv Transmission ◽  
Age Difference ◽  
Transmission Network ◽  
Phylogenetic Methods

ADOLESCENT SEXUALITY AND THE HIV EPIDEMIC IN YAOUNDÉ, CAMEROON

2004 ◽  
Vol 36 (5) ◽  
pp. 597-616 ◽  
Author(s):  
N. LYDIÉ ◽  
N. J. ROBINSON ◽  
B. FERRY ◽  
E. AKAM ◽  
M. DE LOENZIEN ◽  
...  
Keyword(s):  
Young Women ◽  
Hiv Transmission ◽  
Sexual Partners ◽  
Hiv Prevalence ◽  
Large Male ◽  
Age Difference ◽  
Susceptibility To Infection ◽  
Risky Behaviours ◽  
Mixing Patterns ◽  
Using Data

Adolescents are the focus of many interventions that aim to prevent HIV transmission. In order for these interventions to be effective, it is essential to understand adolescents' sexual behaviour. Using data collected in Yaoundé, Cameroon, in 1997, the study analysed risk exposure and HIV prevalence among 426 men and 510 women aged 15–24. Although risky behaviours seem to be more prevalent among young men, their HIV prevalence remains under 1%. In contrast, HIV prevalence is high among young women (7·5%), even those who report having had few sexual partners. Mixing patterns among sexual partners, and especially the age difference between men and women, do not seem to be sufficient to explain the large male–female discrepancy in HIV prevalence that is evident in these data. The results are therefore probably due to a greater susceptibility to infection of young women than men. This study highlights the necessity of reinforcing prevention campaigns among youth and fighting the obstacles that continue to impede the use of condoms in this population.

Abstract 257: Urban Teaching and Non-Teaching Hospitals Outcomes: Myocardial Infarction

2017 ◽  
Vol 10 (suppl_3) ◽  
Author(s):  
Priscilla O Okunji ◽  
Johnnie Daniel
Keyword(s):  
Myocardial Infarction ◽  
Mortality Rate ◽  
Income Group ◽  
The United States ◽  
Teaching Hospitals ◽  
Age Difference ◽  
Age Group ◽  
Urban Teaching ◽  
Significant Difference ◽  
The Impact

Background: Patients with myocardial infarction reportedly have different outcomes on discharge according to hospital characteristics. In the present study, we evaluated the differences between urban teaching hospitals (UTH) and non-teaching hospitals (NTH), discharged in 2012. We also investigated on the outcomes. Methods: Sample of 117,808 subjects diagnosed with myocardial infarction were extracted from a nationwide inpatient stay dataset using the International Classification Data, ICD 9 code 41000 in the United States, according to hospital location, size, and teaching status. Results: The analysis of the data showed that more whites were admitted to both teaching and non teaching hospitals with more males (~24%) admitted than their female counterparts. However, blacks were admitted more (~15%) in urban teaching hospitals than medium urban non teaching hospitals. Age difference was noted as well, while age group (60-79 years) were admitted more in UTH, inversely urban non-teaching hospitals admitted more older (80 years or older) age group. A significant difference (~28%) was observed in both hospital categories with UTH admitting more patients of $1.00 - $38,999.00 income group than other income categories. In addition, it was observed that patients with MI stayed more (~5%) for 14 or more days, and charged more especially for income group of $80,000 or above in UTH than NTH. No significant difference was found in the mortality rate for both hospital categories. Conclusion: The overall outcomes showed that the mortality rate between urban teaching and non-teaching hospitals were non significant, though the inpatients MI stayed longer and were charged more in UTH than NTH. The authors call for the study to be replicated with a higher level of statistical measures to ascertain the impact of the variables on the outcomes for a more validated result.

scholarly journals Knowledge of HIV and benefits of male medical circumcision amongst clients in an urban area

2014 ◽  
Vol 6 (1) ◽  
Author(s):  
Abidemi Faleye
Keyword(s):  
Urban Area ◽  
Hiv Transmission ◽  
World Health ◽  
Routine Practice ◽  
Cross Sectional ◽  
Innovative Methods ◽  
Validated Questionnaire ◽  
Preventative Strategy ◽  
Set Up ◽  
Health Organization

Background: Male medical circumcision (MMC) has been shown to reduce the risk of HIV transmission in circumcised men by up to 60%. Following recommendations from the World Health Organization, South Africa adopted MMC as a preventative strategy against HIV in 2010 and set up circumcision camps across the country. Concerns have been raised about condom avoidance following MMC because of a mistaken belief about the benefits of MMC.Aim and setting: The aim of this study was to describe the profile and knowledge about HIV and circumcision amongst men presenting for MMC in an urban area in KwaZulu-Natal.Methods: This was a cross-sectional descriptive study of 394 clients over the age of 18 years who presented to two MMC sites in Durban between November 2012 and March 2013. A validated questionnaire was used to collect data.Results: The mean age of clients presenting for MMC was 28 years. Most clients were black, single, unemployed and sexually active. The majority presented for MMC because they believed that MMC would reduce their risk of acquiring HIV infection. Knowledge about HIV transmission was very good and 86.3% of clients were aware that risky sexual behaviour suchas condom avoidance could reverse the benefits of MMC.Conclusion: The knowledge of HIV and benefits of MMC was very good amongst those presenting for MMC. However as MMC is primarily a preventative strategy, innovative methods to promote MMC prior to first sexual encounter need to be explored. Further research is needed to determine whether the benefits of MMC on the reduction of HIV transmission aresustained in routine practice. [Full text article to follow]

scholarly journals PREVALENCE OF SMOKING IN ADULT POPULATION OF IRKUTSK

2016 ◽  
Vol 1 (6) ◽  
pp. 153-156
Author(s):  
Максикова ◽  
Tatyana Maksikova ◽  
Бабанская ◽  
Evgeniya Babanskaya ◽  
Меньшикова ◽  
...  
Keyword(s):  
Risk Factor ◽  
Adult Population ◽  
Age Groups ◽  
Significant Risk ◽  
Significant Risk Factor ◽  
Noncommunicable Diseases ◽  
Age Difference ◽  
Age Group ◽  
Considerable Problem ◽  
The One

Smoking is a significant risk factor of chronic noncommunicable diseases. Smoking prevalence is variable in different populations. A study of the prevalence of this risk factor allows to estimate its contribution to the development of cardiovascular pathology, to plan the necessary amount of medical care for people using tobacco, and to determine the effectiveness of prevention activities in the region. As a result of the study, smoking frequency in population of the Irkutsk region older 18years of age or over was established as 29.5%. The number of smokers increased with age, reaching maximum value of 38.6% in the group 30–39 years. Male smokers made maximum in the age group 30–39 years, women – in the age group of 18–19 years. The average age of smokers was 34 years, the one of nonsmokers – 43 years. The age difference was 9 years, and it was lower in the group of men than in the group of women (5 and 11 years, respectively). The number of the smoking men were 3 times larger, than women: 50.2% and 13.5%, respectively. Among persons with arterial hypertension, 22.1% were smoking with the maximum frequency of smoking in age groups from 20 to 49 years. These figures point to a considerable problem of smoking in the region.

scholarly journals To study the prevalence of HIV infection amongst antenatal women in a tertiary care hospital in Gujarat, India

2017 ◽  
Vol 6 (9) ◽  
pp. 3872
Author(s):  
Mahima Jain ◽  
Bhargavkumar K. Nimavat
Keyword(s):  
Hiv Infection ◽  
Hiv Transmission ◽  
Tertiary Care Hospital ◽  
Adult Population ◽  
Tertiary Care ◽  
Rapid Test ◽  
Antiretroviral Drugs ◽  
Care Hospital ◽  
Age Group ◽  
Persons Living With Hiv

Background: India has an estimated 2.1 million persons living with HIV in 2011. The prevalence of HIV among adult population has consistently declined over the last one decade from 0.4% in 2000 to 0.27% in 2011.HIV transmission from infected mother to baby is known to occur. The effective use of Antiretroviral drugs is known to reduce the risk significantly.Methods: This is a retrospective data analysis to know the prevalence of HIV infection among antenatal women attending a tertiary care hospital. All antenatal females are offered pretest counseling, sample collected and tested as per NACO guidelines by Rapid test and ELISA. Results of the test are disclosed after posttest counseling and kept confidential.Results: The seroprevalence over five years in the present study ranges from 0.466% to 0.278%. Women in the age group 21-25 years shows high prevalence due to peak sexual activity in this age group. 56.66% Husbands of these females are reactive which shows the major source of infection.Conclusions: The present study stresses the need to target the population mainly between 21-30 years in various Government programmes, thereby to reduce the transmission from parent to child.

scholarly journals Habitual meal frequency in relation to resting and activity-induced energy expenditure in human subjects: the role of fat-free mass

2003 ◽  
Vol 90 (3) ◽  
pp. 643-649 ◽  
Author(s):  
Margriet S. Westerterp-Plantenga ◽  
Annelies H. C. Goris ◽  
Erwin P. Meijer ◽  
Klaas R. Westerterp
Keyword(s):  
Physical Activity ◽  
Energy Expenditure ◽  
Human Subjects ◽  
Older Men ◽  
Activity Level ◽  
Fat Free Mass ◽  
Meal Frequency ◽  
Younger Women ◽  
Younger Men

Habitual meal frequency was assessed as a possible function of components of energy expenditure (EE) in human subjects. Fifty-six subjects participated (four categories differing in body composition): ten older women (fat-free mass (FFM) 42·0 (sd 6·3) kg, aged 59 (sd 2) years, BMI 27·5 (sd 6·9) kg/m2), fifteen younger women (FFM 45·5 (sd 5·2) kg, aged 34 (sd 10) years, BMI 21·9 (sd 2·3) kg/m2), twelve older men (FFM 56·8 (sd 5·9) kg, aged 62 (sd 4) years, BMI 25·7 (sd 3·3) kg/m2) and nineteen younger men (FFM 63·9 (sd 7·5) kg, aged 23·1 (sd 3·9) years, BMI 22·9 (sd 1·8) kg/m2). Measurements consisted of habitual meal frequency by validated food-intake diaries, physical activity by tri-axial accelerometers and resting EE by a ventilated hood system. Habitual meal frequency was expressed as a function of resting EE (including resting EE as a function of FFM), and of activity-induced EE, using regression analysis. FFM differed according to gender and age categories (P < 0·01). Physical activity level was higher in the younger men than in the other categories (P < 0·05). No relationship of meal frequency with the variables assessed was observed in subjects with a low FFM (the women). In the subjects with a medium FFM (the older men), meal frequency was positively related to resting EE (r2 0·4, P < 0·05), but not to the residuals of resting EE as a function of FFM, and inversely related to activity-induced EE (r2 0·3, P < 0·05). Resting EE explained 40% of the variation in meal frequency; adding activity-induced EE increased this to 60%. In the subjects with a high FFM (the younger men), meal frequency was inversely related to resting EE (r2 0·8, P < 0·0001) and to the residuals of resting EE as a function of FFM (P = 0·03), and positively related to activity-induced EE (r2 0·6, P < 0·0001). Resting EE explained 85% of the variation in meal frequency; adding activity-induced EE increased this to 89%. Habitual meal frequency was a function of components of EE, namely resting EE and activity-induced EE, only in subjects with a medium to high FFM (men). FFM-related differences in these relationships suggest a role of physical activity.

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