Network Research Experiences in New York and Eastern Europe: Lessons for the Southern US in Understanding HIV Transmission Dynamics

Epidemiological characteristics of HIV transmission in southeastern China from 2015 to 2020 based on HIV molecular network

OBJECTIVE

HIV/AIDS remains a global public health problem, and understanding the structure of social networks of people living with HIV/AIDS is of great importance to unravel HIV transmission, propose precision control and reduce new infections. This study aimed to investigate the epidemiological characteristics of HIV transmission in Fujian province, southeastern China from 2015 to 2020 based on HIV molecular network.

METHODS

Newly diagnosed, treatment-naive HIV/AIDS patients were randomly sampled from Fujian province in 2015 and 2020. Plasma was sampled for in-house genotyping resistance test, and HIV molecular network was created using the HIV-TRACE tool. Factors affecting the inclusion of variables in the HIV molecular network were identified using univariate and multivariate logistic regression analyses.

RESULTS

A total of 1,714 eligible cases were finally recruited, including 806 cases in 2015 and 908 cases in 2020. The dominant HIV subtypes were CRF01_AE (41.7%) and CRF07_BC (38.3%) in 2015 and CRF07_BC (53. 3%) and CRF01_AE (29.1%) in 2020, and the prevalence of HIV drug resistance was 4.2% in 2015 and 5.3% in 2020. Sequences of CRF07_BC formed the largest HIV-1 transmission cluster at a genetic distance threshold of both 1.5 and 0.5%. Univariate and multivariate logistic regression analyses showed that ages of under 20 years and over 60 years, CRF07_BC subtype, Han ethnicity, sampling in 2015, absence of HIV drug resistance, married with spouse, sampling from three cities of Jinjiang, Nanping and Quanzhou resulted in higher proportions of sequences included in the HIV transmission molecular network at a genetic distance threshold of 1.5% (p < 0.05).

CONCLUSION

Our findings unravel the HIV molecular transmission network of newly diagnosed HIV/AIDS patients in Fujian province, southeastern China, which facilitates the understanding of HIV transmission patterns in the province.

Integration of a geospatially targeted community-based testing approach with respondent-driven sampling to identify people who inject drugs living with HIV and HCV in Patti and Gorakhpur, India

BACKGROUND

Respondent-driven sampling (RDS), a network recruitment approach, is effective at reaching people who inject drugs (PWID), but other strategies may be needed to reach PWID at risk or living with HIV and/or Hepatitis C (HCV). We examined the impact of integrating geospatially targeted community-based HIV/HCV testing with an RDS survey.

METHODS

PWID were recruited between 2019 and 2021 in Patti and Gorakhpur, India, in a two-phased approach for identifying PWID living with HIV/HCV. Phase 1 was an RDS survey, in which participants reported injection venues. Venues with the highest prevalence of HIV/HCV viremia were selected for Phase 2: community-based testing. All participants underwent rapid HIV and HCV testing and viral load quantification. Using Pearson's chi-squared test, two-sided exact significance tests, and t-tests, we compared prevalence and identification rates for each of the primary outcomes: the number of PWID 1) living with HIV/HCV, 2) undiagnosed, and 3) viremic.

RESULTS

Both approaches identified large numbers of PWID (n∼500 each; N=2011) who were living with HIV/HCV and had transmission potential (i.e., detectable viremia). The community-based approach identified a higher proportion of individuals living with HCV (76.4% vs. 69.6% in Gorakhpur and 36.3% vs. 29.0% in Patti). Community-based testing was also faster at identifying PWID with detectable HIV viremia. Both approaches identified PWID with varying demographic characteristics.

CONCLUSIONS

Community-based testing was more efficient than RDS overall, but both may be required to reach PWID of varying characteristics. Surveillance should collect data on injection venues to facilitate community-based testing and maximize case identification.

Methods for Assessing Spillover in Network-Based Studies of HIV/AIDS Prevention among People Who Use Drugs

Human Immunodeficiency Virus (HIV) interventions among people who use drugs (PWUD) often have spillover, also known as interference or dissemination, which occurs when one participant's exposure affects another participant's outcome. PWUD are often members of networks defined by social, sexual, and drug-use partnerships and their receipt of interventions can affect other members in their network. For example, HIV interventions with possible spillover include educational training about HIV risk reduction, pre-exposure prophylaxis, or treatment as prevention. In turn, intervention effects frequently depend on the network structure, and intervention coverage levels and spillover can occur even if not measured in a study, possibly resulting in an underestimation of intervention effects. Recent methodological approaches were developed to assess spillover in the context of network-based studies. This tutorial provides an overview of different study designs for network-based studies and related methodological approaches for assessing spillover in each design. We also provide an overview of other important methodological issues in network studies, including causal influence in networks and missing data. Finally, we highlight applications of different designs and methods from studies of PWUD and conclude with an illustrative example from the Transmission Reduction Intervention Project (TRIP) in Athens, Greece.

Social support networks of users of crack cocaine and the role of a Brazilian health program for people living on the street: A qualitative study

This cross-sectional qualitative study analyzed characteristics of social support for users of crack cocaine and the role of "Consultório na Rua" (CR), or "Office in the Street," a Brazilian program for people living on the street. Data were collected using 1) ethnographic field observations during the delivery of services from this program, 2) in-depth interviews with 17 users of crack cocaine, and 3) a focus group with professionals from CR. To analyze data, we used content analysis and analytical categories based on Social Network Analysis (SNA) theoretical statements. Results showed that family, peers, community members, and professionals from CR were the main social support providers. Participants mentioned receiving material, informational, and emotional support from CR members. It was observed that CR had a welcoming and inclusive approach, but CR team members identified challenges related to stigma directed toward people who use substances and live on the street. CR assumed a central role in the health and social assistance of users of crack cocaine living on the street, providing an important link to healthcare and social services. However, initiatives related to motivation to receive mental health services, treatment, or social reintegration were not observed in conjunction with this program.

HIV-1 Transmission linkages among persons with incident infection to inform public health surveillance

BACKGROUND

We evaluated features of HIV transmission networks involving persons diagnosed during incident HIV infection (IHI) to assess network-based opportunities to curtail onward transmission.

METHODS

Transmission networks were constructed using partial pol sequences reported to North Carolina surveillance among persons with recent (2014-2018) and past (<2014) HIV diagnoses. IHI were defined as documented acute infections or seroconversion. Demographic and virologic features of HIV genetic clusters (<1.5% pairwise genetic distance) involving ≥ 1 IHI were assessed. Persons with viral genetic links and who had diagnoses >90 days prior to an IHI were further characterized. We assessed named partner outcomes among IHI index persons using contact tracing data.

FINDINGS

Of 4,405 HIV diagnoses 2014-2018 with sequences, there were 323 (7%) IHI index persons; most were male (88%), Black (65%), young (68% <30 years), and reported sex with men (MSM) risk (79%). Index persons were more likely to be cluster members compared to non-index persons diagnosed during the same period (72% vs. 49%). In total, 162 clusters were identified involving 233 IHI, 577 recent diagnoses, and 163 past diagnoses. Most IHI cases (53%) had viral linkages to ≥1 previously diagnosed person without evidence of HIV viral suppression in the year prior to the diagnosis of the IHI index. In contact tracing, only 53% IHI cases named an HIV-positive contact, resulting in 0.5 previously diagnosed persons detected per IHI investigated. When combined with viral analyses, the detection rate of viremic previously diagnosed persons increased to 1.3.

INTERPRETATION

Integrating public health with molecular epidemiology, revealed that more than half of IHI have viral links to persons with previously diagnosed unsuppressed HIV infection which was largely unrecognized by traditional contact tracing. Enhanced partner services to support engagement and retention in HIV care and improved case finding supported by rapid phylogenetic analysis are tools to substantially reduce onward HIV transmission.

Sociometric Risk Network Structure, HIV Prevalence, and Drug Injection-Related Norms among People Who Inject Drugs (PWID) in Athens, Greece

Background: Structural properties of sociometric networks have been associated with behaviors related to HIV transmission. Very few studies, however, have explored the correlation between sociometric network factors and drug injection-related norms. Methods: This exploratory work: (i) describes basic structural qualities of a sociometric risk network of participants in the Transmission Reduction Intervention Project (TRIP) in Athens, Greece, in the context of a large HIV outbreak among people who inject drugs (PWID); (ii) measures HIV prevalence within specific structures within the sociometric risk network of PWID in TRIP; and (iii) explores the association of structural properties of the sociometric risk network in TRIP with drug injection-related norms. Results: The sociometric risk network in TRIP consisted of a large component (n = 241, 67.8%), a few small components (n = 36, 10.1%) with 2-10 individuals each, and some isolates (n = 79, 22.2%). HIV prevalence was significantly higher in the large component (55.6%), the 2-core (59.1%) and 3-core (66.3%) of the large component, and the 3-cliques of the cores. Drug injection-related norms were significantly associated with structural characteristics of the sociometric risk network. A safe behavioral pattern (use of unclean cooker/filter/rinse water was never encouraged) was significantly (p = 0.03) less normative among people who TRIP participants of the 2-core injected with (40.5%) than among network contacts of TRIP participants outside the 2-core (55.6%). On the contrary, at drug-using venues, 2-core members reported that safer behaviors were normative compared to what was reported by those without 2-core membership. Conclusions: Sociometric network data can give useful insights into HIV transmission dynamics and inform prevention strategies.Supplemental data for this article is available online at https://doi.org/10.1080/10826084.2021.1914103 .

Giving syphilis and gonorrhea to friends: using in-person friendship networks to find additional cases of gonorrhea and syphilis

Background

Syphilis and gonorrhea reached an all-time high in 2018. The resurgence of syphilis and gonorrhea requires innovative methods of sexual contact tracing that encourage disclosure of same-sex sexual contacts that might otherwise be suppressed. Over 75% of Grindr mobile phone application users report seeking “friendship,” so this study asked people diagnosed with syphilis and gonorrhea to identify their friends.

Methods

Patients at the two Baltimore sexually transmitted infection (STI) clinics and the Baltimore City Health Department were asked 12 questions to elicit members of their friendship networks before eliciting sexual networks. The study included 353 index cases and 172 friendship contacts, yielding a friendship network of 331 non-isolates (n = 331) and sexual-only network of 140 non-isolates. The data were plotted and analyzed using exponential family random graph analysis.

Results

Eliciting respondents’ in-person social contacts yielded 12 syphilis cases and 6 gonorrhea cases in addition to the 16 syphilis cases and 4 gonorrhea cases that would have been found with sexual contacts alone. Syphilis is clustered within sexual (odds ratio = 2.2, 95% confidence interval (1.36, 3.66)) and social contacts (OR = 1.31, 95% CI (1.02, 1.68)). Gonorrhea is clustered within reported social (OR = 1.56, 95% CI (1.22, 2.00)) but not sexual contacts (OR = 0.98, 95% CI (0.62, 1.53)).

Conclusions

Eliciting friendship networks of people diagnosed with syphilis and gonorrhea may find members of their sexual networks, drug use networks, or people of similar STI risk. Friendship networks include more diagnosed cases of syphilis and gonorrhea than sexual networks alone, especially among populations with many non-disclosing men who have sex with men (MSM) and women who have sex with women (WSW). Future research should evaluate whether this friendship network method of contact tracing can be implemented by adapting automated mobile phone COVID-19 contact tracing protocols, if these COVID-19 contact tracing methods are able to maintain anonymity and public trust.

Giving syphilis and gonorrhea to friends: Using in-person friendship networks to find additional cases of gonorrhea and syphilis

Background

Syphilis and gonorrhea reached an all-time high in 2018. The resurgence of syphilis and gonorrhea requires innovative methods of sexual contact tracing that encourage disclosure of same-sex sexual contacts that might otherwise be suppressed. Over 75% of Grindr mobile phone application users report seeking "friendship," so this study asked people diagnosed with syphilis and gonorrhea to identify their friends.

Methods

Patients at the two Baltimore sexually transmitted infection (STI) clinics and the Baltimore City Health Department were asked 12 questions to elicit members of their friendship networks before eliciting sexual networks. The study included 353 index cases and 172 friendship contacts, yielding a friendship network of 331 non-isolates (n=331) and sexual-only network of 140 non-isolates. The data were plotted and analyzed using exponential family random graph analysis.

Results

Eliciting respondents' in-person social contacts yielded 12 syphilis cases and 6 gonorrhea cases in addition to the 16 syphilis cases and 4 gonorrhea cases that would have been found with sexual contacts alone. Syphilis is clustered within sexual (odds ratio=2.2, 95% confidence interval (1.36, 3.66)) and social contacts (OR=1.31,95% CI (1.02, 1.68)). Gonorrhea is clustered within reported social (OR=1.56, 95% CI (1.22, 2.00)) but not sexual contacts (OR=0.98, 95% CI (0.62, 1.53)).

Conclusions

Eliciting friendship networks of people diagnosed with syphilis and gonorrhea may find members of their sexual networks, drug use networks, or people of similar STI risk. Friendship networks include more diagnosed cases of syphilis and gonorrhea than sexual networks alone, especially among populations with many non-disclosing men who have sex with men (MSM) and women who have sex with women (WSW). Future research should evaluate whether this friendship network method of contact tracing can be implemented by adapting automated mobile phone COVID-19 contact tracing protocols, if these COVID-19 contact tracing methods are able to maintain anonymity and public trust.

Giving syphilis and gonorrhea to friends: Using in-person friendship networks to find additional cases of gonorrhea and syphilis

BACKGROUND

Syphilis and gonorrhea reached an all-time high in 2018. The resurgence of syphilis and gonorrhea requires innovative methods of sexual contact tracing that encourage disclosure of same-sex sexual contacts that might otherwise be suppressed. Over 75% of Grindr mobile phone application users report seeking "friendship," so this study asked people diagnosed with syphilis and gonorrhea to identify their friends.

METHODS

Patients at the two Baltimore sexually transmitted infection (STI) clinics and the Baltimore City Health Department were asked 12 questions to elicit members of their friendship networks before eliciting sexual networks. The study included 353 index cases and 172 friendship contacts, yielding a friendship network of 331 non-isolates (n=331) and sexual-only network of 140 non-isolates. The data were plotted and analyzed using exponential family random graph analysis.

RESULTS

Eliciting respondents' in-person social contacts yielded 12 syphilis cases and 6 gonorrhea cases in addition to the 16 syphilis cases and 4 gonorrhea cases that would have been found with sexual contacts alone. Syphilis is clustered within sexual (odds ratio=2.2, 95% confidence interval (1.36, 3.66)) and social contacts (OR=1.31, 95% CI (1.02, 1.68)). Gonorrhea is clustered within reported social (OR=1.56, 95% CI (1.22, 2.00)) but not sexual contacts (OR=0.98, 95% CI (0.62, 1.53)).

CONCLUSIONS

Eliciting friendship networks of people diagnosed with syphilis and gonorrhea may find members of their sexual networks, drug use networks, or people of similar STI risk. Friendship networks include more diagnosed cases of syphilis and gonorrhea than sexual networks alone, especially among populations with many non-disclosing men who have sex with men (MSM) and women who have sex with women (WSW). Future research should evaluate whether this friendship network method of contact tracing can be implemented by adapting automated mobile phone COVID-19 contact tracing protocols, if these COVID-19 contact tracing methods are able to maintain anonymity and public trust.

Social network approaches to locating people recently infected with HIV in Odessa, Ukraine

Introduction

This paper examines the extent to which an intervention succeeded in locating people who had recently become infected with HIV in the context of the large‐scale Ukrainian epidemic. Locating and intervening with people who recently became infected with HIV (people with recent infection, or PwRI) can reduce forward HIV transmission and help PwRI remain healthy.

Methods

The Transmission Reduction Intervention Project (TRIP) recruited recently‐infected and longer‐term infected seeds in Odessa, Ukraine, in 2013 to 2016, and asked them to help recruit their extended risk network members. The proportions of network members who were PwRI were compared between TRIP arms (i.e. networks of recently‐infected seeds vs. networks of longer‐term infected seeds) and to the proportion of participants who were PwRI in an RDS‐based Integrated Biobehavioral Surveillance of people who inject drugs in 2013.

Results

The networks of PwRI seeds and those of longer‐term infected seeds had similar (2%) proportions who were themselves PwRI. This was higher than the 0.25% proportion in IBBS (OR = 7.80; p = 0.016). The odds ratio among the subset of participants who injected drugs was 11.17 (p = 0.003). Cost comparison analyses using simplified ingredients‐based methods found that TRIP spent no more than US $4513 per PwRI located whereas IBBS spent $11,924.

Conclusions

Further research is needed to confirm these results and improve TRIP further, but our findings suggest that interventions that trace the networks of people who test HIV‐positive are a cost‐effective way to locate PwRI and reduce HIV transmission and should therefore be implemented.

New Measures for Research on Men Who Have Sex with Men and for At-Risk Heterosexuals: Tools to Study Links Between Structural Interventions or Large-Scale Social Change and HIV Risk Behaviors, Service Use, and Infection

Large-scale structural interventions and "Big Events" like revolutions, wars and major disasters can affect HIV transmission by changing the sizes of at-risk populations, making high-risk behaviors more or less likely, or changing contexts in which risk occurs. This paper describes new measures to investigate hypothesized pathways that could connect macro-social changes to subsequent HIV transmission. We developed a "menu" of novel scales and indexes on topics including norms about sex and drug injecting under different conditions, experiencing denial of dignity, agreement with cultural themes about what actions are needed for survival or resistance, solidarity and other issues. We interviewed 298 at-risk heterosexuals and 256 men who have sex with men in New York City about these measures and possible validators for them. Most measures showed evidence of criterion validity (absolute magnitude of Pearson's r ≥ 0.20) and reliability (Cronbach's alpha ≥ 0.70). These measures can be (cautiously) used to understand how macro-changes affect HIV and other risk. Many can also be used to understand risk contexts and dynamics in more normal situations. Additional efforts to improve and to replicate the validation of these measures should be conducted.