Beyond risk compensation : clusters of antiretroviral treatment (ART) users in sexual networks can modify the impact of ART on HIV incidence

Introduction : Concerns about risk compensation-increased risk behaviours in response to a perception of reduced HIV transmission risk-after the initiation of ART have largely been dispelled in empirical studies, but other changes in sexual networking patterns may still modify the effects of ART on HIV incidence. Methods : We developed an exploratory mathematical model of HIV transmission that incorporates the possibility of ART clusters, i.e. subsets of the sexual network in which the density of ART patients is much higher than in the rest of the network. Such clusters may emerge as a result of ART homophily-a tendency for ART patients to preferentially form and maintain relationships with other ART patients. We assessed whether ART clusters may affect the impact of ART on HIV incidence, and how the influence of this effect-modifying variable depends on contextual variables such as HIV prevalence, HIV serosorting, coverage of HIV testing and ART, and adherence to ART. Results : ART homophily can modify the impact of ART on HIV incidence in both directions. In concentrated epidemics and generalized epidemics with moderate HIV prevalence (approximate to 10%), ART clusters can enhance the impact of ART on HIV incidence, especially when adherence to ART is poor. In hyperendemic settings (approximate to 35% HIV prevalence), ART clusters can reduce the impact of ART on HIV incidence when adherence to ART is high but few people living with HIV (PLWH) have been diagnosed. In all contexts, the effects of ART clusters on HIV epidemic dynamics are distinct from those of HIV serosorting. Conclusions : Depending on the programmatic and epidemiological context, ART clusters may enhance or reduce the impact of ART on HIV incidence, in contrast to serosorting, which always leads to a lower impact of ART on HIV incidence. ART homophily and the emergence of ART clusters should be measured empirically and incorporated into more refined models used to plan and evaluate ART programmes

Age differences between sexual partners, behavioural and demographic correlates, and HIV infection on Likoma Island, Malawi

Patterns of age differences between sexual partners-"age-mixing"-may partially explain the magnitude of HIV epidemics in Sub-Saharan Africa. However, evidence of age-disparity as a risk factor for HIV remains mixed. We used data from a socio-centric study of sexual behaviour in Malawi to quantify the age-mixing pattern and to find associations between relationship characteristics and age differences for 1,922 participants. Three age difference measures were explored as predictors of prevalent HIV infection. We found that for each year increase in male participant age, the average age difference with their partners increased by 0.26 years, while among women it remained approximately constant around 5 years. Women in the study had larger within-individual variation in partner ages compared to men. Spousal partnerships and never using a condom during sex were associated with larger age differences in relationships of both men and women. Men who were more than five years younger than their partners had 5.39 times higher odds ( 95% CI: 0.93-31.24) of being HIV-infected than men 0-4 years older. The relationship between HIV-infection and age-asymmetry may be more complex than previously described. The role that women play in HIV transmission should not be underestimated, particularly in populations with large within-individual variation in partner ages

Impact of measles supplementary immunization activities on reaching children missed by routine programs.

BACKGROUND: Measles supplementary immunization activities (SIAs) are vaccination campaigns that supplement routine vaccination programs with a recommended second dose opportunity to children of different ages regardless of their previous history of measles vaccination. They are conducted every 2-4 years and over a few weeks in many low- and middle-income countries. While SIAs have high vaccination coverage, it is unclear whether they reach the children who miss their routine measles vaccine dose. Determining who is reached by SIAs is vital to understanding their effectiveness, as well as measure progress towards measles control. METHODS: We examined SIAs in low- and middle-income countries from 2000 to 2014 using data from the Demographic and Health Surveys. Conditional on a child's routine measles vaccination status, we examined whether children participated in the most recent measles SIA. RESULTS: The average proportion of zero-dose children (no previous routine measles vaccination defined as no vaccination date before the SIA) reached by SIAs across 14 countries was 66%, ranging from 28% in São Tomé and Príncipe to 91% in Nigeria. However, when also including all children with routine measles vaccination data, this proportion decreased to 12% and to 58% when imputing data for children with vaccination reported by the mother and vaccination marks on the vaccination card across countries. Overall, the proportions of zero-dose children reached by SIAs declined with increasing household wealth. CONCLUSIONS: Some countries appeared to reach a higher proportion of zero-dose children using SIAs than others, with proportions reached varying according to the definition of measles vaccination (e.g., vaccination dates on the vaccination card, vaccination marks on the vaccination card, and/or self-reported data). This suggests that some countries could improve their targeting of SIAs to children who miss other measles vaccine opportunities. Across all countries, SIAs played an important role in reaching children from poor households

Should home-based HIV testing and counseling services be offered periodically in programs of ARV treatment as prevention? A case study in Likoma (Malawi).

To reduce HIV incidence, prevention programs centered on the use of antiretrovirals require scaling-up HIV testing and counseling (HTC). Home-based HTC services (HBHTC) increase HTC coverage, but HBHTC has only been evaluated during one-off campaigns. Two years after an initial HBHTC campaign ("round 1"), we conducted another HBHTC campaign ("round 2") in Likoma (Malawi). HBHTC participation increased during round 2 among women (from 74 to 83%, P < 0.01). New HBHTC clients were recruited, especially at ages 25 and older. Only 6.9% of women but 15.9% of men remained unreached by HBHTC after round 2. HIV prevalence during round 2 was low among clients who were HIV-negative during round 1 (0.7%), but high among women who received their first ever HIV test during round 2 (42.8%). The costs per newly diagnosed infection increased significantly during round 2. Periodically conducting HBHTC campaigns can further increase HTC, but supplementary interventions to enroll individuals not reached by HBHTC are needed

Spillover effects of HIV testing policies: changes in HIV testing guidelines and HCV testing practices in drug treatment programs in the United States

Background: To examine the extent to which state adoption of the Centers for Disease Control and Prevention (CDC) 2006 revisions to adult and adolescent HIV testing guidelines is associated with availability of other important prevention and medical services. We hypothesized that in states where the pretest counseling requirement for HIV testing was dropped from state legislation, substance use disorder treatment programs would have higher availability of HCV testing services than in states that had maintained this requirement. Methods: We analyzed a nationally representative sample of 383 opioid treatment programs from the 2005 and 2011 National Drug Abuse Treatment System Survey (NDATSS). Data were collected from program directors and clinical supervisors through telephone surveys. Multivariate logistic regression models were used to measure associations between state adoption of CDC recommended guidelines for HIV pretest counseling and availability of HCV testing services. Results: The effects of HIV testing legislative changes on HCV testing practices varied by type of opioid treatment program. In states that had removed the requirement for HIV pretest counseling, buprenorphine-only programs were more likely to offer HCV testing to their patients. The positive spillover effect of HIV pretest counseling policies, however, did not extend to methadone programs and did not translate into increased availability of on-site HCV testing in either program type. Conclusions: Our findings highlight potential positive spillover effects of HIV testing policies on HCV testing practices. They also suggest that maximizing the benefits of HIV policies may require other initiatives, including resources and programmatic efforts that support systematic integration with other services and effective implementation

The Social and the Sexual: Networks in Contemporary Demographic Research

The analysis of networks has become an important theme in contemporary demographic research in both developed and developing countries, including investigations of the determinants of fertility behaviors, the interaction between social network and social structures and population policies, the role of intergenerational networks in aging societies, and the relevance for sexual networks for the spread of HIV AIDS. This paper reviews the current research on networks across several domains in demographic research, and it discusses some of the specific challenges of network-based approaches with respect to data collection, analytic approaches and methodologies, interpretation of results, and micro-to-macro aggregation by drawing on research conducted as part of the Kenyan Diffusion and Ideational Change Project (KDICP), the Malawi Longitudinal Study of Families and Health (MLSFH) and the Likoma Network Study (LNS)

Revisiting the Recommended Duration of Interviews Conducted by Mobile Phone in Low- and Middle-income Countries: A Randomized Trial in Malawi

Guidelines for conducting surveys by mobile phone calls in low- and middle-income countries suggest keeping interviews short (&lt;20 minutes). The evidence supporting this recommendation is scant, even though limiting interview duration might reduce the amount of data generated by such surveys. We recruited nearly 2,500 mobile phone users in Malawi and randomly allocated them to 10-, 20-, or 30-minute phone interviews, all ending with questions on parental survival. Cooperation was high in all groups, and differences in completion rates were minimal. The extent of item nonresponse, age heaping, and temporal displacement of deaths in data on parental survival generally did not vary between study groups, but reports of maternal age at death were more reliable in longer interviews. Recommendations about the duration of mobile phone interviews might be too restrictive. They should not preclude additional modules, including ones on mortality, in mobile phone surveys conducted in LMICs

Increased Age Heaping in Mobile Phone Surveys Conducted in Low-Income and Middle-Income Countries

Since the beginning of the coronavirus disease 2019 pandemic, the number of surveys conducted remotely by mobile phone in low-income and middle-income countries has increased rapidly. This shift has helped sustain data collection despite restrictions on mobility and interactions. It might also allow collecting data more frequently on important demographic and socioeconomic topics. However, conducting interviews by mobile phone might affect the accuracy of reported data, for example, if respondents have difficulties understanding questions asked remotely, or data collectors have less time to probe and cross-check answers. In this visualization, the authors explore time trends in age heaping, a strong signal of reporting errors, in six African countries. They show that mobile phone surveys have generated noisier data on age than recent household surveys and censuses, thus possibly affecting researchers’ understanding of demographic processes and confounding multivariate analyses of socioeconomic outcomes

Childhood Illness Prevalence and Health Seeking Behavior Patterns in Rural Tanzania

Introduction This paper identifies factors influencing differences in the prevalence of diarrhea, fever and acute respiratory infection (ARI), and health seeking behavior among caregivers of children under age five in rural Tanzania. Methods Using cross-sectional survey data collected in Kilombero, Ulanga, and Rufiji districts, the analysis included 1,643 caregivers who lived with 2,077 children under five years old. Logistic multivariate and multinomial regressions were used to analyze factors related to disease prevalence and to health seeking behavior. Results One quarter of the children had experienced fever in the past two weeks, 12.0 % had diarrhea and 6.7 % experienced ARI. Children two years of age and older were less likely to experience morbidity than children under one year [ORfever = 0.77, 95 % CI 0.61-0.96; ORdiarrhea = 0.26, 95 % CI 0.18-0.37; ORARI = 0.60 95 % CI 0.41-0.89]. Children aged two and older were more likely than children under one to receive no care or to receive care at home, rather than to receive care at a facility [RRRdiarrhea = 3.47, 95 % CI 1.19-10.17 for “No care”]. Children living with an educated caregiver were less likely to receive no care or home care rather than care at a facility as compared to those who lived with an uneducated caregiver [RRRdiarrhea = 0.28, 95 % CI 1.10-0.79 for “No care”]. Children living in the wealthiest households were less likely to receive no care or home care for fever as compared to those who lived poorest households. Children living more than 1 km from health facility were more likely to receive no care or to receive home care for diarrhea rather than care at a facility as compared to those living less than 1 km from a facility [RRRdiarrhea = 3.50, 95 % CI 1.13-10.82 for “No care”]. Finally, caregivers who lived with more than one child under age five were more likely to provide no care or home care rather than to seek treatment at a facility as compared to those living with only one child under five. Conclusions Our results suggest that child age, caregiver education attainment, and household wealth and location may be associated with childhood illness and care seeking behavior patterns. Interventions should be explored that target children and caregivers according to these factors, thereby better addressing barriers and optimizing health outcomes especially for children at risk of dying before the age of five

Collecting mortality data via mobile phone surveys: A non-inferiority randomized trial in Malawi

Despite the urgent need for timely mortality data in low-income and lower-middle-income countries, mobile phone surveys rarely include questions about recent deaths. Such questions might a) be too sensitive, b) take too long to ask and/or c) generate unreliable data. We assessed the feasibility of mortality data collection using mobile phone surveys in Malawi. We conducted a non-inferiority trial among a random sample of mobile phone users. Participants were allocated to an interview about their recent economic activity or recent deaths in their family. In the group that was asked mortality-related questions, half of the respondents completed an abridged questionnaire, focused on information necessary to calculate recent mortality rates, whereas the other half completed an extended questionnaire that also included questions about symptoms and healthcare. The primary trial outcome was the cooperation rate, i.e., the number of completed interviews divided by the number of mobile subscribers invited to participate. Secondary outcomes included self-reports of negative feelings and stated intentions to participate in future interviews. We called more than 7,000 unique numbers and reached 3,054 mobile subscribers. In total, 1,683 mobile users were invited to participate. The difference in cooperation rates between those asked to complete a mortality-related interview and those asked to answer questions about economic activity was 0.9 percentage points (95% CI = -2.3, 4.1), which satisfied the non-inferiority criterion. The mortality questionnaire was non-inferior to the economic questionnaire on all secondary outcomes. Collecting mortality data required 2 to 4 additional minutes per reported death, depending on the inclusion of questions about symptoms and healthcare. More than half of recent deaths elicited during mobile phone interviews had not been registered with the National Registration Bureau. Including mortality-related questions in mobile phone surveys is feasible. It might help strengthen the surveillance of mortality in countries with deficient civil registration systems. Registration: AEA RCT Registry, #0008065 (14 September 2021).</jats:p