The Impact of Human Mobility on HIV Transmission in Kenya

Exploring mobility data for enhancing HIV care engagement in Black/African American and Hispanic/Latinx individuals: a longitudinal observational study protocol

INTRODUCTION

Increasing engagement in HIV care among people living with HIV, especially those from Black/African American and Hispanic/Latinx communities, is an urgent need. Mobility data that measure individuals' movements over time in combination with sociostructural data (eg, crime, census) can potentially identify barriers and facilitators to HIV care engagement and can enhance public health surveillance and inform interventions.

METHODS AND ANALYSIS

The proposed work is a longitudinal observational cohort study aiming to enrol 400 Black/African American and Hispanic/Latinx individuals living with HIV in areas of the USA with high prevalence rates of HIV. Each participant will be asked to share at least 14 consecutive days of mobility data per month through the study app for 1 year and complete surveys at five time points (baseline, 3, 6, 9 and 12 months). The study app will collect Global Positioning System (GPS) data. These GPS data will be merged with other data sets containing information related to HIV care facilities, other healthcare, business and service locations, and sociostructural data. Machine learning and deep learning models will be used for data analysis to identify contextual predictors of HIV care engagement. The study includes interviews with stakeholders to evaluate the implementation and ethical concerns of using mobility data to increase engagement in HIV care. We seek to study the relationship between mobility patterns and HIV care engagement.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Institutional Review Board of the University of California, Irvine (#20205923). Collected data will be deidentified and securely stored. Dissemination of findings will be done through presentations, posters and research papers while collaborating with other research teams.

Digital Epidemiological Approaches in HIV Research: a Scoping Methodological Review

PURPOSE OF REVIEW

The purpose of this scoping review was to summarize literature regarding the use of user-generated digital data collected for non-epidemiological purposes in human immunodeficiency virus (HIV) research.

RECENT FINDINGS

Thirty-nine papers were included in the final review. Four types of digital data were used: social media data, web search queries, mobile phone data, and data from global positioning system (GPS) devices. With these data, four HIV epidemiological objectives were pursued, including disease surveillance, behavioral surveillance, assessment of public attention to HIV, and characterization of risk contexts. Approximately one-third used machine learning for classification, prediction, or topic modeling. Less than a quarter discussed the ethics of using user-generated data for epidemiological purposes. User-generated digital data can be used to monitor, predict, and contextualize HIV risk and can help disrupt trajectories of risk closer to onset. However, more attention needs to be paid to digital ethics and the direction of the field in a post-Application Programming Interface (API) world.

Non-adherence to antiretroviral treatment among migrating fishermen in western Kenya's islands: a rapid qualitative study

Fishing communities in many Sub-Saharan African countries are a high-risk population group disproportionately affected by the HIV epidemic. The association of migration with HIV and AIDS in sub-Saharan Africa is well documented. Frequent mobility, high consumption of alcohol, multiple sexual partners, transactional and commercial sex, poor health infrastructure and limited access to health services are reported among the main factors shaping the HIV epidemic in fishing communities. Moreover, studies have been conducted in sub-Saharan Africa on adherence to antiretroviral treatment (ART) among fishers; however, non-adherence to ART remains poorly understood among migrating fishermen in the western Kenya islands. This qualitative study investigated factors contributing to non-adherence among fishermen in the western Kenya islands. This study utilised 51 in-depth interviews and six focus group discussions to highlight factors contributing to non-adherence to ART by mobile fishermen. Data were analysed using a contextualised thematic analysis. Results show that migration, alcohol consumption and ART sharing contributed to non-adherence. Adherence to ART is a powerful predictor of survival for individuals living with HIV and AIDS. The Kenyan government can use lessons from this study to target fishermen to achieve the UNAIDS 2025 recommendations on people-centred and context-specific service responses to AIDS as this would move Kenya closer to the 90% reduction in annual infections by 2030. This article contributes to a deeper understanding of how and why fishermen from the islands in western Kenya struggle to adhere to treatment even though they can access ARTs through the public health care system. Longitudinal studies should be conducted to explore how the factors associated with non-adherence correlate with other key health outcomes such as drug resistance.

Factors Associated with Short and Long Term Mobility and HIV Risk of Women Living in Fishing Communities Around Lake Victoria in Kenya, Tanzania, and Uganda: A Cross Sectional Survey

Mobility is linked to negative HIV care continuum outcomes. We sought to understand factors associated with short and long term mobility among women in fishing communities in Kenya, Tanzania, and Uganda. From 2018 through 2019 we conducted a cross-sectional survey of women aged 15 years and above, randomly selected from a census of six fishing villages, around Lake Victoria. Data collected included: demographics, risky sexual behaviour on the most recent trip, and travel behaviour in the previous 4 months. Mobility was recorded as any overnight trip outside the participant's village. A two-level multinomial logistic regression model was used to determine the associated factors. A total of 901 participants were enrolled, of whom 645 (71.6%) reported travelling (53.4%; short and 18.2% long term trips). Five factors were associated with long term travel: age, travel purpose, frequency of travel, sexual behaviour while travelling, and destination. Trips made by women aged 46-75 years were less likely to be long term. Long term trips were more common if the trip was to visit, rather than to trade, and more common for women who reported one or two trips rather than three or more trips. Women who made long term trips were more likely to engage in unprotected sex while on a trip. Women who travelled to a regional town/district or another town/district were more likely to take long term trips. The factors associated with travel duration among women living in fishing communities could inform planning of future health care interventions in these communities.

Cross-municipality migration and spread of tuberculosis in South Africa

Human migration facilitates the spread of infectious disease. However, little is known about the contribution of migration to the spread of tuberculosis in South Africa. We analyzed longitudinal data on all tuberculosis test results recorded by South Africa's National Health Laboratory Service (NHLS), January 2011-July 2017, alongside municipality-level migration flows estimated from the 2016 South African Community Survey. We first assessed migration patterns in people with laboratory-diagnosed tuberculosis and analyzed demographic predictors. We then quantified the impact of cross-municipality migration on tuberculosis incidence in municipality-level regression models. The NHLS database included 921,888 patients with multiple clinic visits with TB tests. Of these, 147,513 (16%) had tests in different municipalities. The median (IQR) distance travelled was 304 (163 to 536) km. Migration was most common at ages 20-39 years and rates were similar for men and women. In municipality-level regression models, each 1% increase in migration-adjusted tuberculosis prevalence was associated with a 0.47% (95% CI: 0.03% to 0.90%) increase in the incidence of drug-susceptible tuberculosis two years later, even after controlling for baseline prevalence. Similar results were found for rifampicin-resistant tuberculosis. Accounting for migration improved our ability to predict future incidence of tuberculosis.

HIV screening and linkage to care in a health department in Valencia, Spain: Lessons learned from a healthcare quality improvement project

Spain's rate of new human immunodeficiency virus (HIV) diagnoses exceeds that of the European Economic Area average (8.6 vs 5.6:100,000 in 2018). The country has failed to meet the first of United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets for HIV control by 2020, with 87.0% of people living with HIV knowing their status, and late presentation rates of 47.6% and 51.5% country-wide and in the Valencian autonomous community, respectively. Advancing screening and linkage to care (SLTC) practices is necessary to effectively control the epidemic. The Valencia Viral Screening (CRIVALVIR) project adopted the TEST model for opportunistic and systematic HIV SLTC in individuals aged 18 to 80 who required blood work for any purpose, as of February 2019. SLTC was integrated into routine clinical workflow across primary care centers serving a population of 360,000 people in Valencia, Spain. Our project successfully upscaled total HIV testing by 194% to over 32,000 patients tested in 14 months. We found an overall prevalence of 0.13% (0.08-0.21) among those screened per protocol (n = 13,061), with foreign-born citizens presenting a 12.5 times significantly higher likelihood of acquiring HIV (95% confidence interval 4.63-33.96, P < .0001). We improved late presentation by 18.2 percentage points and prevented an estimated 58 to 70 new secondary infections. HIV screening of the general population in primary care is an effective strategy for achieving timely diagnosis and preventing new infections. Opportunistic, systematic, opt-out approaches are essential to control the HIV epidemic.

Sexual partnership concurrency and age disparities associated with sexually transmitted infection and risk behavior in rural communities in Kenya and Uganda

OBJECTIVES

We examined sex-specific associations of partner age disparity and relationship concurrency with Neisseria gonorrhoeae and/or Chlamydia trachomatis (NG/CT) infection, higher-risk relationships, and condom use as proxies for HIV risk.

METHODS

Data were collected in 2016 from 2179 adults in 12 communities in Uganda and Kenya. Logistic regression models examined associations of age disparity and relationship concurrency with NG/CT infection, condom use, and higher-risk (commercial sex and other higher-risk) relationships in the past 6 months, controlling for covariates.

RESULTS

Partner age and relationship concurrency were associated with NG/CT infection in women but not men. Relative to women in age-disparate relationships, women in both age-disparate and age-homogeneous relationships had higher odds of NG/CT infection (adjusted odds ratio [aOR]=3.82, 95% confidence interval [CI]: 1.46-9.98). Among men and women, partnership concurrency was associated with higher-risk partnerships. In addition, relative to those with a single age-homogeneous partner, those with concurrent age-homogeneous partners had higher odds of condom use (men: aOR=2.85, 95% CI: 1.89-4.31; women: aOR=2.99, 95% CI: 1.52-5.89). Concurrent age-disparate partnerships were associated with condom use among men only (aOR=4.02, 95% CI: 2.54-6.37).

CONCLUSION

Findings underscore the importance of targeted HIV prevention efforts for couples in age-disparate and concurrent relationships.

Modelling the geographical spread of HIV among MSM in Guangdong, China: a metapopulation model considering the impact of pre-exposure prophylaxis

Men who have sex with men (MSM) make up the majority of new human immunodeficiency virus (HIV) diagnoses among young people in China. Understanding HIV transmission dynamics among the MSM population is, therefore, crucial for the control and prevention of HIV infections, especially for some newly reported genotypes of HIV. This study presents a metapopulation model considering the impact of pre-exposure prophylaxis (PrEP) to investigate the geographical spread of a hypothetically new genotype of HIV among MSM in Guangdong, China. We use multiple data sources to construct this model to characterize the behavioural dynamics underlying the spread of HIV within and between 21 prefecture-level cities (i.e. Guangzhou, Shenzhen, Foshan, etc.) in Guangdong province: the online social network via a gay social networking app, the offline human mobility network via the Baidu mobility website, and self-reported sexual behaviours among MSM. Results show that PrEP initiation exponentially delays the occurrence of the virus for the rest of the cities transmitted from the initial outbreak city; hubs on the movement network, such as Guangzhou, Shenzhen, and Foshan are at a higher risk of 'earliest' exposure to the new HIV genotype; most cities acquire the virus directly from the initial outbreak city while others acquire the virus from cities that are not initial outbreak locations and have relatively high betweenness centralities, such as Guangzhou, Shenzhen and Shantou. This study provides insights in predicting the geographical spread of a new genotype of HIV among an MSM population from different regions and assessing the importance of prefecture-level cities in the control and prevention of HIV in Guangdong province. This article is part of the theme issue 'Data science approach to infectious disease surveillance'.

The Epidemiological Analysis of HIV/AIDS Patients: Sexually Transmitted Diseases Department VS. Other Departments in A General Hospital of Shanghai, China

BACKGROUND

Hospital is an important place for HIV/AIDS screening, and a general hospital is composed of multiple departments. Different departments have different levels of understanding of HIV/AIDS, especially the sexually transmitted diseases (STD) department is the main place for HIV/AIDS screening.

OBJECTIVE

The study aims to validate the common knowledge that the STD department is an important place for HIV/AIDS screening by comparing the epidemiological characteristics of HIV/AIDS patients in the STD department and other departments in Tongji Hospital, which can provide a theoretical basis for the precise and differentiated control of HIV/AIDS.

METHODS

A total of 283,525 HIV screening cases were analyzed from January 1st 2006 to December 31st 2018 in the STD department and other departments. The epidemiological data of 226 HIV/AIDS cases were retrospectively analyzed.

RESULTS

Firstly, the incidence of HIV/AIDS in the population served by Tongji Hospital was higher than that in Shanghai and China. Secondly, the positive rate of HIV screening test in the STD department was ten times higher than that of other departments. Thirdly, the social-demographic characteristics of HIV/AIDS patients in the STD department were different from those in other departments. Fourthly, there were differences in age, education, marital status and number of sex partners between men who have sex with men (MSM) and men who have sex with women (MSW). Fifthly, there was no difference except age in social-demographic characteristics of MSM between the STD department and other departments. Sixthly, compared with other departments, the majority of HIV/AIDS patients in the STD department were MSM. Seventhly, syphilis and HIV co-infection were not statistically significant in HIV/AIDS patients between the STD department and other departments.

CONCLUSION

Firstly, the significantly higher positive rate of an HIV screening test in the STD department emphasizes its importance as a place for screening HIV/AIDS patients. Secondly, HIV/AIDS patients diagnosed in the general hospital were mainly transmitted by sexual contact, and MSM accounted for the most part of these patients. More attention should be paid to screen outpatients, especially in the STD department and young men.

Using mobile phone data to reveal risk flow networks underlying the HIV epidemic in Namibia

Twenty-six million people are living with HIV in sub-Saharan Africa; epidemics are widely dispersed, due to high levels of mobility. However, global elimination strategies do not consider mobility. We use Call Detail Records from 9 billion calls/texts to model mobility in Namibia; we quantify the epidemic-level impact by using a mathematical framework based on spatial networks. We find complex networks of risk flows dispersed risk countrywide: increasing the risk of acquiring HIV in some areas, decreasing it in others. Overall, 40% of risk was mobility-driven. Networks contained multiple risk hubs. All constituencies (administrative units) imported and exported risk, to varying degrees. A few exported very high levels of risk: their residents infected many residents of other constituencies. Notably, prevalence in the constituency exporting the most risk was below average. Large-scale networks of mobility-driven risk flows underlie generalized HIV epidemics in sub-Saharan Africa. In order to eliminate HIV, it is likely to become increasingly important to implement innovative control strategies that focus on disrupting risk flows.

A Bibliometric Analysis and Network Visualisation of Human Mobility Studies from 1990 to 2020: Emerging Trends and Future Research Directions

Studies on human mobility have a long history with increasingly strong interdisciplinary connections across social science, environmental science, information and technology, computer science, engineering, and health science. However, what is lacking in the current research is a synthesis of the studies to identify the evolutional pathways and future research directions. To address this gap, we conduct a systematic review of human mobility-related studies published from 1990 to 2020. Drawing on the selected publications retrieved from the Web of Science, we provide a bibliometric analysis and network visualisation using CiteSpace and VOSviewer on the number of publications and year published, authors and their countries and afflictions, citations, topics, abstracts, keywords, and journals. Our findings show that human mobility-related studies have become increasingly interdisciplinary and multi-dimensional, which have been strengthened by the use of the so-called ‘big data’ from multiple sources, the development of computer technologies, the innovation of modelling approaches, and the novel applications in various areas. Based on our synthesis of the work by top cited authors we identify four directions for future research relating to data sources, modelling methods, applications, and technologies. We advocate for more in-depth research on human mobility using multi-source big data, improving modelling methods and integrating advanced technologies including artificial intelligence, and machine and deep learning to address real-world problems and contribute to social good.

The differential impacts of non-locally acquired infections and treatment interventions on heterosexual HIV transmission in Hong Kong

Introduction

Heterosexual infections have contributed to a high proportion of the HIV burden in Asia and Eastern Europe. Human mobility and non-local infections are important features in some cities/countries. An understanding of the determinants of the sustained growth of the heterosexual HIV epidemics would enable the potential impacts of treatment-based interventions to be assessed.

Methods

We developed a compartmental model for heterosexual HIV transmissions, parameterized by clinical and surveillance data (1984–2014) in Hong Kong. HIV sequence data were included for examining genetic linkages and clustering pattern. We performed sensitivity analyses to evaluate effects of high-risk sexual partnership and proportions of non-locally acquired infections. Four hypothetical interventions (a) immediate treatment, (b) enhancement of retention in care, (c) HIV testing campaigns, and (d) test-and-treat strategy, were examined.

Results

Data of 2174 patients (723 female and 1451 male) diagnosed with HIV between 1984 and 2012 in Hong Kong were collected for model parameterization. Among 1229 sequences of non-MSM (men who have sex with men) patients, 70% were isolates and 17% were either dyads or triads. In base-case scenario, the total estimated number of new infections in 2012–2023 would be 672 for male and 452 for female. Following 100% retention in care intervention, the total proportion of averted new infections in 2012–2023 would be 7% for male and 10% for female. HIV testing campaign in 2012 and 2017 followed by 100% immediate treatment strategy would avert 5% and 9% of male and female new infections, respectively. In the epidemic model, an increase of high-risk sexual partnership from 6% to 9% would increase the epidemic growth (annual number of newly diagnosed and newly infected cases) by about 10%. If no non-locally acquired infection occurred as from 2012, the epidemic growth would slump. To control the heterosexual epidemic, periodic HIV testing at 5-year intervals with immediate treatment would avert 5–13% of annual new infections in 2013–2023.

Conclusions

Enhanced HIV testing with immediate treatment is most effective in controlling the heterosexual epidemic, the impacts of which might however be attenuated by any increase of non-locally acquired infection, assuming little variations of high risk partnership over time.

The dynamics of a simple, risk-structured HIV model

Many diseases, such as HIV, are heterogeneous for risk. In this paper, we study an infectious-disease model for a population with demography, mass-action incidence, an arbitrary number of risk classes, and separable mixing. We complement our general analyses with two specific examples. In the first example, the mean of the components of the transmission coefficients decreases as we add more risk classes. In the second example, the mean stays constant but the variance decreases. For each example, we determine the disease-free equilibrium, the basic reproduction number, and the endemic equilibrium. We also characterize the spectrum of eigenvalues that determine the stability of the endemic equilibrium. For both examples, the basic reproduction number decreases as we add more risk classes. The endemic equilibrium, when present, is asymptotically stable. Our analyses suggest that risk structure must be modeled correctly, since different risk structures, with similar mean properties, can produce different dynamics.

MODELING DISPROPORTIONAL EFFECTS OF EDUCATING INFECTED KENYAN YOUTH ON HIV/AIDS

We formulate an age and sex-structured deterministic model to assess the effect of increasing comprehensive knowledge of HIV/AIDS disease in the infected Adolescent Girls and Young Women (AGYW) and, Adolescent Boys and Young Men (ABYM) populations in Kenya. Mathematical analysis of infection through sub-network analysis was carried out to trace various infection routes and the veracity of various transmission routes as well as the associated probabilities. Using HIV data in Kenya on our model, disproportional effects were observed when dispensation of comprehensive knowledge of HIV/AIDS was preferred in one population over the other. Effective dispensation of comprehensive knowledge of HIV/AIDS in both the infected AGYW and ABYM populations significantly slows down the infection spread but may not eradicate it.

Human population movement can impede the elimination of soil-transmitted helminth transmission in regions with heterogeneity in mass drug administration coverage and transmission potential between villages: a metapopulation analysis

BACKGROUND

Soil-transmitted helminth (STH) infections affect predominantly socio-economically disadvantaged populations in sub-Saharan Africa, East Asia and the Americas. Previous mathematical modelling studies have evaluated optimal intervention strategies to break STH transmission in clusters of villages. These studies assumed that villages are closed independent units with no movement of people in or out of communities. Here we examine how human population movement, for example, of seasonal migrant labourers, affect the outcome of mass drug administration (MDA) programmes.

RESULTS

We used a stochastic individual-based metapopulation model to analyse the impact of human population movement at varying rates on STH elimination efforts. Specifically, we looked at seasonal clumped movement events of infected individuals into a village. We showed that even if on average 75% of the entire resident population within a village are treated, an annual rate of 2-3% of the population arriving from an untreated source village can reduce the probability of STH elimination to less than 50% in high-prevalence settings. If a village is infection-free, an annual movement rate of 2-3% from an infected source village imposes a risk of re-introduction of STH of 75% or higher, unless the prevalence in the source village is less than 20%. Even a single arrival of 2-3% of the population can impose a risk of re-introducing STH of 50% or greater depending on the prevalence in the source village. The risk of re-introduction also depends on both the age group of moving individuals and STH species, since the pattern of cross-sectional age-prevalence and age-intensity profiles of infection in the human host are species-specific.

CONCLUSIONS

Planning for STH elimination programmes should account for human mobility patterns in defined regions. We recommend that individuals arriving from areas with ongoing STH transmission should receive preventive chemotherapy for STHs. This can most easily be implemented if migration is seasonal and overlaps with treatment rounds, e.g. seasonal migrant labour. Moreover, transmission hotspots in or near treatment clusters should be eliminated, for example, by implementing appropriate water, sanitation and hygiene (WASH) measures and targeting treatment to individuals living in hotspots.

Gendered dimensions of population mobility associated with HIV across three epidemics in rural Eastern Africa

Mobility in sub-Saharan Africa links geographically-separate HIV epidemics, intensifies transmission by enabling higher-risk sexual behavior, and disrupts care. This population-based observational cohort study measured complex dimensions of mobility in rural Uganda and Kenya. Survey data were collected every 6 months beginning in 2016 from a random sample of 2308 adults in 12 communities across three regions, stratified by intervention arm, baseline residential stability and HIV status. Analyses were survey-weighted and stratified by sex, region, and HIV status. In this study, there were large differences in the forms and magnitude of mobility across regions, between men and women, and by HIV status. We found that adult migration varied widely by region, higher proportions of men than women migrated within the past one and five years, and men predominated across all but the most localized scales of migration: a higher proportion of women than men migrated within county of origin. Labor-related mobility was more common among men than women, while women were more likely to travel for non-labor reasons. Labor-related mobility was associated with HIV positive status for both men and women, adjusting for age and region, but the association was especially pronounced in women. The forms, drivers, and correlates of mobility in eastern Africa are complex and highly gendered. An in-depth understanding of mobility may help improve implementation and address gaps in the HIV prevention and care continua.

Measuring mobility, disease connectivity and individual risk: a review of using mobile phone data and mHealth for travel medicine

RATIONALE FOR REVIEW

The increasing mobility of populations allows pathogens to move rapidly and far, making endemic or epidemic regions more connected to the rest of the world than at any time in history. However, the ability to measure and monitor human mobility, health risk and their changing patterns across spatial and temporal scales using traditional data sources has been limited. To facilitate a better understanding of the use of emerging mobile phone technology and data in travel medicine, we reviewed relevant work aiming at measuring human mobility, disease connectivity and health risk in travellers using mobile geopositioning data.

KEY FINDINGS

Despite some inherent biases of mobile phone data, analysing anonymized positions from mobile users could precisely quantify the dynamical processes associated with contemporary human movements and connectivity of infectious diseases at multiple temporal and spatial scales. Moreover, recent progress in mobile health (mHealth) technology and applications, integrating with mobile positioning data, shows great potential for innovation in travel medicine to monitor and assess real-time health risk for individuals during travel.

CONCLUSIONS

Mobile phones and mHealth have become a novel and tremendously powerful source of information on measuring human movements and origin-destination-specific risks of infectious and non-infectious health issues. The high penetration rate of mobile phones across the globe provides an unprecedented opportunity to quantify human mobility and accurately estimate the health risks in travellers. Continued efforts are needed to establish the most promising uses of these data and technologies for travel health.

HIV/AIDS prevention practices among military personnel in Northwest Ethiopia

The spread of HIV/AIDS is a major public health problem in military personnel in Africa. However, the epidemiological evidence regarding HIV/AIDS prevention practices among military personnel in Ethiopia remains unclear. The aim of this study was to investigate HIV/AIDS prevention practices among military personnel in Northwest Ethiopia. A cross-sectional study among military personnel (n = 410) was conducted in Northwest Ethiopia in 2015. Data were collected using a pre-tested questionnaire. Multivariable logistic regression model was fitted to ascertain factors influencing participation in HIV/AIDS prevention programs. About one-fourth (24.6%) of the military personnel had multiple sexual partners, of whom 24.7% failed to use condoms regularly when having sex with non-regular sexual partners. Majority of the sample (n = 355, 86.6%) participated in HIV/AIDS prevention programs. Military personnel who had multiple sexual partners were 6.3 times more likely to report history of non-participation in HIV/AIDS prevention programs (AOR = 6.3, CI₉₅ = 3.5-11.54). A considerable proportion of military personnel had multiple sexual partners with lower levels of condom utilization with non-regular sexual partners. The study further demonstrated misconceptions about HIV/AIDS in Ethiopian military personnel, which reduce their likelihood of participation in HIV/AIDS prevention programs. Health authorities need to strengthen and accelerate HIV/AIDS prevention programs focusing towards military personnel.

Deep clinical and biological phenotyping of the preterm birth and small for gestational age syndromes: The INTERBIO-21 st Newborn Case-Control Study protocol

Background: INTERBIO-21 ^st is Phase II of the INTERGROWTH-21 ^st Project, the population-based, research initiative involving nearly 70,000 mothers and babies worldwide coordinated by Oxford University and performed by a multidisciplinary network of more than 400 healthcare professionals and scientists from 35 institutions in 21 countries worldwide. Phase I, conducted 2008-2015, consisted of nine complementary studies designed to describe optimal human growth and neurodevelopment, based conceptually on the WHO prescriptive approach. The studies generated a set of international standards for monitoring growth and neurodevelopment, which complement the existing WHO Child Growth Standards. Phase II aims to improve the functional classification of the highly heterogenous preterm birth and fetal growth restriction syndromes through a better understanding of how environmental exposures, clinical conditions and nutrition influence patterns of human growth from conception to childhood, as well as specific neurodevelopmental domains and associated behaviors at 2 years of age.

Methods: In the INTERBIO-21 ^st Newborn Case-Control Study, a major component of Phase II, our objective is to investigate the mechanisms potentially responsible for preterm birth and small for gestational age and their interactions, using deep phenotyping of clinical, growth and epidemiological data and associated nutritional, biochemical, omic and histological profiles. Here we describe the study sites, population characteristics, study design, methodology and standardization procedures for the collection of longitudinal clinical data and biological samples (maternal blood, umbilical cord blood, placental tissue, maternal feces and infant buccal swabs) for the study that was conducted between 2012 and 2018 in Brazil, Kenya, Pakistan, South Africa, Thailand and the UK.

Discussion: Our study provides a unique resource for the planned analyses given the range of potentially disadvantageous exposures (including poor nutrition, pregnancy complications and infections) in geographically diverse populations worldwide. The study should enhance current medical knowledge and provide new insights into environmental influences on human growth and neurodevelopment.

Deep clinical and biological phenotyping of the preterm birth and small for gestational age syndromes: The INTERBIO-21 st Newborn Case-Control Study protocol

Background: INTERBIO-21 ^st is Phase II of the INTERGROWTH-21 ^st Project, the population-based, research initiative involving nearly 70,000 mothers and babies worldwide coordinated by Oxford University and performed by a multidisciplinary network of more than 400 healthcare professionals and scientists from 35 institutions in 21 countries worldwide. Phase I, conducted 2008-2015, consisted of nine complementary studies designed to describe optimal human growth and neurodevelopment, based conceptually on the WHO prescriptive approach. The studies generated a set of international standards for monitoring growth and neurodevelopment, which complement the existing WHO Child Growth Standards. Phase II aims to improve the functional classification of the highly heterogenous preterm birth and fetal growth restriction syndromes through a better understanding of how environmental exposures, clinical conditions and nutrition influence patterns of human growth from conception to childhood, as well as specific neurodevelopmental domains and associated behaviors at 2 years of age. Methods: In the INTERBIO-21 ^st Newborn Case-Control Study, a major component of Phase II, our objective is to investigate the mechanisms potentially responsible for preterm birth and small for gestational age and their interactions, using deep phenotyping of clinical, growth and epidemiological data and associated nutritional, biochemical, omic and histological profiles. Here we describe the study sites, population characteristics, study design, methodology and standardization procedures for the collection of longitudinal clinical data and biological samples (maternal blood, umbilical cord blood, placental tissue, maternal feces and infant buccal swabs) for the study that was conducted between 2012 and 2018 in Brazil, Kenya, Pakistan, South Africa, Thailand and the UK. Discussion: Our study provides a unique resource for the planned analyses given the range of potentially disadvantageous exposures (including poor nutrition, pregnancy complications and infections) in geographically diverse populations worldwide. The study should enhance current medical knowledge and provide new insights into environmental influences on human growth and neurodevelopment.

Data triangulation to estimate age-specific coverage of voluntary medical male circumcision for HIV prevention in four Kenyan counties

BACKGROUND

Kenya is 1 of 14 priority countries in Africa scaling up voluntary medical male circumcision (VMMC) for HIV prevention following the recommendations of the World Health Organization and the Joint United Nations Programme on HIV/AIDS. To inform VMMC target setting, we modeled the impact of circumcising specific client age groups across several Kenyan geographic areas.

METHODS

The Decision Makers' Program Planning Tool, Version 2 (DMPPT 2) was applied in Kisumu, Siaya, Homa Bay, and Migori counties. Initial modeling done in mid-2016 showed coverage estimates above 100% in age groups and geographic areas where demand for VMMC continued to be high. On the basis of information obtained from country policy makers and VMMC program implementers, we adjusted circumcision coverage for duplicate reporting, county-level population estimates, migration across county boundaries for VMMC services, and replacement of traditional circumcision with circumcisions in the VMMC program. To address residual inflated coverage following these adjustments we applied county-specific correction factors computed by triangulating model results with coverage estimates from population surveys.

RESULTS

A program record review identified duplicate reporting in Homa Bay, Kisumu, and Siaya. Using county population estimates from the Kenya National Bureau of Statistics, we found that adjusting for migration and correcting for replacement of traditional circumcision with VMMC led to lower estimates of 2016 male circumcision coverage especially for Kisumu, Migori, and Siaya. Even after addressing these issues, overestimation of 2016 male circumcision coverage persisted, especially in Homa Bay. We estimated male circumcision coverage in 2016 by applying correction factors. Modeled estimates for 2016 circumcision coverage for the 10- to 14-year age group ranged from 50% in Homa Bay to approximately 90% in Kisumu. Results for the 15- to 19-year age group suggest almost complete coverage in Kisumu, Migori, and Siaya. Coverage for the 20- to 24-year age group ranged from about 80% in Siaya to about 90% in Homa Bay, coverage for those aged 25-29 years ranged from about 60% in Siaya to 80% in Migori, and coverage in those aged 30-34 years ranged from about 50% in Siaya to about 70% in Migori.

CONCLUSIONS

Our analysis points to solutions for some of the data issues encountered in Kenya. Kenya is the first country in which these data issues have been encountered because baseline circumcision rates were high. We anticipate that some of the modeling methods we developed for Kenya will be applicable in other countries.

Roads and the spread of HIV in Africa

I here use GIS and HIV data from five African countries to estimate the effect of road proximity on HIV infection. I find a negative effect of the distance to the nearest paved road on the probability of being infected with HIV: a one standard-deviation fall in this distance (approximately 2.4 km) increases the probability of infection by 0.6-2.0 percentage points. Using slope as an instrument for road distance continues to produce a negative and significant estimated coefficient. However this relationship may also reflect selection and reverse causality in individual choice of location, and I extensively discuss the role of migration. While the number of lifetime sexual partners is significantly influenced by the presence of roads in some recent years, the effect of road distance on access to protection has disappeared.

Epidemic as a natural process

Mathematical epidemiology is a well-recognized discipline to model infectious diseases. It also provides guidance for public health officials to limit outbreaks. Nevertheless, epidemics take societies by surprise every now and then, for example, when the Ebola virus epidemic raged seemingly unrestrained in Western Africa. We provide insight to this capricious character of nature by describing the epidemic as a natural process, i.e., a phenomenon governed by thermodynamics. Our account, based on statistical mechanics of open systems, clarifies that it is impossible to predict accurately epidemic courses because everything depends on everything else. Nonetheless, the thermodynamic theory yields a comprehensive and analytical view of the epidemic. The tenet subsumes various processes in a scale-free manner from the molecular to the societal levels. The holistic view accentuates overarching procedures in arresting and eradicating epidemics.

Big Data's Role in Precision Public Health

Precision public health is an emerging practice to more granularly predict and understand public health risks and customize treatments for more specific and homogeneous subpopulations, often using new data, technologies, and methods. Big data is one element that has consistently helped to achieve these goals, through its ability to deliver to practitioners a volume and variety of structured or unstructured data not previously possible. Big data has enabled more widespread and specific research and trials of stratifying and segmenting populations at risk for a variety of health problems. Examples of success using big data are surveyed in surveillance and signal detection, predicting future risk, targeted interventions, and understanding disease. Using novel big data or big data approaches has risks that remain to be resolved. The continued growth in volume and variety of available data, decreased costs of data capture, and emerging computational methods mean big data success will likely be a required pillar of precision public health into the future. This review article aims to identify the precision public health use cases where big data has added value, identify classes of value that big data may bring, and outline the risks inherent in using big data in precision public health efforts.

Frequent implementation of interventions may increase HIV infections among MSM in China

Intervention measures among men who have sex with men (MSM) are usually designed to reduce the frequency of high risk behaviors (within-community level), but unfortunately may change the contact network and consequently increase the opportunity for them to have sex with new partners (between-community level). A multi-community periodic model on complex network is proposed to study the two-side effects of interventions on HIV transmission among MSM in China, in which the wanning process of the impacts of interventions are modelled. The basic reproduction number for the multi-community periodic system is defined and calculated numerically. Based on the number of annual reported HIV/AIDS cases among MSM in China, the unknown parameters are estimated by using MCMC method and the basic reproduction number is estimated as 3.56 (95%CI [3.556, 3.568]). Our results show that strong randomness of the community-connection networks leads to more new infections and more HIV/AIDS cases. Moreover, main conclusion indicates that implementation of interventions may induce more new infections, depending on relative level of between- and within-community impacts, and the frequency of implementation of interventions. The findings can help to guide the policy maker to choose the appropriate intervention measures, and to implement the interventions with proper frequency.

Connecting Mobility to Infectious Diseases: The Promise and Limits of Mobile Phone Data

Human travel can shape infectious disease dynamics by introducing pathogens into susceptible populations or by changing the frequency of contacts between infected and susceptible individuals. Quantifying infectious disease-relevant travel patterns on fine spatial and temporal scales has historically been limited by data availability. The recent emergence of mobile phone calling data and associated locational information means that we can now trace fine scale movement across large numbers of individuals. However, these data necessarily reflect a biased sample of individuals across communities and are generally aggregated for both ethical and pragmatic reasons that may further obscure the nuance of individual and spatial heterogeneities. Additionally, as a general rule, the mobile phone data are not linked to demographic or social identifiers, or to information about the disease status of individual subscribers (although these may be made available in smaller-scale specific cases). Combining data on human movement from mobile phone data-derived population fluxes with data on disease incidence requires approaches that can tackle varying spatial and temporal resolutions of each data source and generate inference about dynamics on scales relevant to both pathogen biology and human ecology. Here, we review the opportunities and challenges of these novel data streams, illustrating our examples with analyses of 2 different pathogens in Kenya, and conclude by outlining core directions for future research.