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Mathematical models within the Ross-Macdonald framework increasingly play a role in our understanding of vector-borne disease dynamics and as tools for assessing scenarios to respond to emerging threats. These threats are typically characterized by a high degree of heterogeneity, introducing a range of possible complexities in models and challenges to maintain the link with empirical evidence. We systematically identified and analysed a total of 77 published papers presenting compartmental West Nile virus (WNV) models that use parameter values derived from empirical studies. Using a set of 15 criteria, we measured the dissimilarity compared with the Ross-Macdonald framework. We also retrieved the purpose and type of models and traced the empirical sources of their parameters. Our review highlights the increasing refinements in WNV models. Models for prediction included the highest number of refinements. We found uneven distributions of refinements and of evidence for parameter values. We identified several challenges in parametrizing such increasingly complex models. For parameters common to most models, we also synthesize the empirical evidence for their values and ranges. The study highlights the potential to improve the quality of WNV models and their applicability for policy by establishing closer collaboration between mathematical modelling and empirical work.

Background: To reduce HIV incidence among adolescent girls who sell sex (AGSS) in Zimbabwe, we need to better understand how vulnerabilities intersect with HIV infection and how those living with HIV engage in care., Methods: In 2017, we conducted social mapping in 4 locations in Zimbabwe and recruited girls aged 16-19 years who sell sex, using respondent-driven sampling or census sampling methods. Participants completed a questionnaire and provided finger prick blood samples for HIV antibody testing., Results: Of 605 AGSS recruited, 74.4% considered themselves sex workers, 24.4% reported experiencing violence in the past year, 91.7% were not in school, and 83.8% had less than a complete secondary education. Prevalence of HIV increased steeply from 2.1% among those aged 16 years to 26.9% among those aged 19 years; overall, 20.2% of AGSS were HIV-positive. In the multivariate analysis, age, education, marital status, and violence from a client were associated with HIV. Among the 605 AGSS, 86.3% had ever tested for HIV, with 64.1% having tested in the past 6 months. Among AGSS living with HIV, half (50.8%) were aware of their status, among whom 83.9% reported taking antiretroviral therapy., Conclusion: The steep rise in HIV prevalence among those aged between 16 and 19 years suggests the window to engage with AGSS before HIV acquisition is short. To accelerate reductions in incidence among AGSS, intensified combination prevention strategies that address structural factors and tailor services to the needs of AGSS are required, particularly ensuring girls enroll and remain in school., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: Surveillance of recent HIV infections in national testing services has the potential to inform primary prevention programming activities. Focusing on procedures required to accurately determine recent infection, and the potential for recent infection surveillance to inform prevention efforts, we present the results of three independent but linked pilots of recency testing., Methods: To distinguish recently acquired HIV infection from long-standing infection, in 2018 we applied a Recent Infection Testing Algorithm that combined a laboratory-based Limiting Antigen Avidity Enzyme Immunoassay with clinical information (viral-load; history of prior HIV diagnosis; antiretroviral therapy-exposure). We explored potential misclassification of test results and analysed the characteristics of participants with recent infection. We applied the algorithm in antenatal clinics providing prevention of mother-to-child transmission services in Siaya County, Kenya, outreach sites serving female sex workers in Zimbabwe, and routine HIV testing and counselling facilities in Nairobi, Kenya. In Nairobi, we also conducted recency testing among partners of HIV-positive participants., Results: In Siaya County, 2.3% (10/426) of HIV-positive pregnant women were classified as recent. A risk factor analysis comparing women testing recent with those testing HIV-negative found women in their first trimester were significantly more likely to test recent than those in their second or third trimester. In Zimbabwe, 10.5% (33/313) of female sex workers testing HIV-positive through the outreach programme were classified recent. A risk factor analysis of women testing recent versus those testing HIV-negative, found no strong evidence of an association with recent infection. In Nairobi, among 532 HIV-positive women and men, 8.6% (46) were classified recent. Among partners of participants, almost a quarter of those who tested HIV-positive were classified as recent (23.8%; 5/21). In all three settings, the inclusion of clinical information helped improve the positive predictive value of recent infection testing by removing cases that were likely misclassified., Conclusions: We successfully identified recently acquired infections among persons testing HIV-positive in routine testing settings and highlight the importance of incorporating additional information to accurately classify recent infection. We identified a number of groups with a significantly higher proportion of recent infection, suggesting recent infection surveillance, when rolled-out nationally, may help in further targeting primary prevention efforts., (© 2020 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)

Background: Serological tests can distinguish recent (in the prior 12 months) from long-term HIV infection. Integrating recency testing into routine HIV testing services (HTS) can provide important information on transmission clusters and prioritize clients for partner testing. This study assessed the feasibility and use of integrating HIV recency into routine testing., Methods: We conducted a multi-method study at 14 facilities in Kenya, and key informant interviews with health care providers. We abstracted clinical record data, collected specimens, tested specimens for recent infection, returned results to participants, and conducted a follow-up survey for those recently infected., Results: From March to October 2018, we enrolled 532 clients who were diagnosed HIV-positive for the first time. Of these, 46 (8.6%) were recently infected. Women aged 15-24 years had 2.9 (95% confidence interval: 1.46 to 5.78) times higher adjusted odds of recent infection compared with 15-24-year-old men and those tested within the past 12 months having 2.55 (95% confidence interval: 0.38 to 4.70) times higher adjusted odds compared with those tested ≥12 months previously. Fourteen of 17 providers interviewed found the integration of recency testing into routine HTS services acceptable and feasible. Among clients who completed the follow-up interview, most (92%) felt that the recency results were useful., Conclusions: Integrating recent infection testing into routine HTS services in Kenya is feasible and largely acceptable to clients and providers. More studies should be done on possible physical and social harms related to returning results, and the best uses of the recent infection data at an individual and population level.