Partial indoor residual spraying with pirimiphos-methyl as an effective and cost-saving measure for the control of Anopheles gambiae s.l. in northern Ghana.

The scale up of indoor residual spraying (IRS) and insecticide treated nets have contributed significantly to global reductions in malaria prevalence over the last two decades. However, widespread pyrethroid resistance has necessitated the use of new and more expensive insecticides for IRS. Partial IRS with pirimiphos-methyl in experimental huts and houses in a village-wide trial was evaluated against Anopheles gambiae s.l. in northern Ghana. Four different scenarios in which either only the top or bottom half of the walls of experimental huts were sprayed, with or without also spraying the ceiling were compared. Mortality of An. gambiae s.l. on partially sprayed walls was compared with the standard procedures in which all walls and ceiling surfaces are sprayed. A small-scale trial was then conducted to assess the effectiveness, feasibility, and cost of spraying only the upper walls and ceiling as compared to full IRS and no spraying in northern Ghana. Human landing catches were conducted to estimate entomological indices and determine the effectiveness of partial IRS. An established transmission dynamics model was parameterized by an analysis of the experimental hut data and used to predict the epidemiological impact and cost effectiveness of partial IRS for malaria control in northern Ghana. In the experimental huts, partial IRS of the top (IRR 0.89, p = 0.13) or bottom (IRR 0.90, p = 0.15) half of walls and the ceiling was not significantly less effective than full IRS in terms of mosquito mortality. In the village trial, the annual entomological inoculation rate was higher for the unsprayed control (217 infective bites/person/year (ib/p/yr)) compared with the fully and partially sprayed sites, with 28 and 38 ib/p/yr, respectively. The transmission model predicts that the efficacy of partial IRS against all-age prevalence of malaria after six months would be broadly equivalent to a full IRS campaign in which 40% reduction is expected relative to no spray campaign. At scale, partial IRS in northern Ghana would have resulted in a 33% cost savings ($496,426) that would enable spraying of 36,000 additional rooms. These findings suggest that partial IRS is an effective, feasible, and cost saving approach to IRS that could be adopted to sustain and expand implementation of this key malaria control intervention.

Differences in inducibility of the latent HIV reservoir in perinatal and adult infection.

The HIV latent reservoir in resting memory CD4+ T cells precludes cure. Therapeutics to reactivate and eliminate this reservoir are in clinical trials in adults, but not yet in pediatric populations. We determined, ex vivo, the inducibility of the latent reservoir in perinatal infection as compared with adult infections using the Tat/rev induced limiting dilution assay (TILDA), in which a single round (12 hours) of CD4+ T cell stimulation with PMA/ionomycin maximally activates T cells and leads to proviral expression with multiply spliced HIV RNA production. Markers of immune activation and exhaustion were measured to assess interactions with inducibility. Although rates of T cell activation with PMA/ionomycin were similar, the latent reservoir in perinatal infection was slower to reactivate and of lower magnitude compared with adult infection, independent of proviral load. An enhanced TILDA with the addition of phytohemagglutin and a duration of 18 hours augmented proviral expression in perinatal but not adult infection. The baseline HLA-DR+CD4+ T cell level was significantly lower in perinatal compared with adult infections, but not correlated with induced reservoir size. These data support the hypothesis that there are differences in kinetics of latency reversal and baseline immune activation in perinatal compared with adult infections, with implications for latency reversal strategies toward reservoir clearance and remission.

The Latent Human Immunodeficiency Virus (HIV) Reservoir Resides Primarily in CD32-CD4+ T Cells in Perinatally HIV-Infected Adolescents With Long-Term Virologic Suppression.

Background: High-level expression of the Fcγ receptor, CD32hi, on CD4+ T cells was associated with enhanced human immunodeficiency virus (HIV) infection of the latent reservoir in a study of adults receiving antiretroviral therapy. We tested the hypothesis that CD32 was the preferential marker of the latent HIV reservoir in virally suppressed, perinatally HIV-infected adolescents. Methods: The frequency of CD32hiCD4+ T cells was determined by flow cytometry (N = 5) and the inducible HIV reservoir in both CD32hi and CD32-CD4+ T cells was quantified (N = 4) with a quantitative viral outgrowth assay. Viral outgrowth was measured by the standard p24 enzyme-linked immunosorbent assay and an ultrasensitive p24 assay (Simoa; Quanterix) with lower limits of quantitation. Results: We found a 59.55-fold enrichment in the absolute number of infectious cells in the CD32- population compared with CD32hi cells. Exponential HIV replication occurred exclusively in CD32-CD4+ T cells (mean change, 17.46 pg/mL; P = .04). Induced provirus in CD32hiCD4+ T cells replicated to substantially lower levels, which did not increase significantly over time (mean change, 0.026 pg/mL; P = .23) and were detected only with the Simoa assay. Conclusions: Our data suggests that the latent HIV reservoir resides mainly in CD32-CD4+ T cells in virally suppressed, perinatally HIV-infected adolescents, which has implications for reservoir elimination strategies.

The microbiome and HIV persistence: implications for viral remission and cure.

PURPOSE OF REVIEW: This article discusses the interaction between HIV infection, the gut microbiome, inflammation and immune activation, and HIV reservoirs, along with interventions to target the microbiome and their implications for HIV remission and cure. RECENT FINDINGS: Most studies show that HIV-infected adults have a gut microbiome associated with decreased bacterial richness and diversity, and associated systemic inflammation and immune activation. A unique set of individuals, elite controllers, who spontaneously control HIV replication, have a similar microbiome to HIV-uninfected individuals. Conversely, exposure to maternal HIV in infants was shown to alter the gut microbiome, even in infants who escaped perinatal infection. Emerging research highlights the importance of the metabolomics and metaproteomics of the gut microbiome, which may have relevance for HIV remission and cure. Together, these studies illustrate the complexity of the relationship between HIV infection, the gut microbiome, and its systemic effects. SUMMARY: Understanding the association of HIV with the microbiome, metabolome, and metaproteome may lead to novel therapies to decrease inflammation and immune activation, and impact HIV reservoir size and vaccine responses. Further research in this area is important to inform HIV remission and cure treatments.

Group counselling improves quality for patients with limited health literacy.

BACKGROUND: The North County Health Centre in Reston, Virginia, recently enhanced the quality and accessibility of physician-coordinated behavioural counselling. METHODS: A patient survey confirmed that the clinic could improve behaviour change support. Physician time constraints, practice productivity issues and treatment priorities were identified barriers to systems change. Systems changes included teamwork, group visits, community engagement and trusted online consumer resources. Validated statistical process control (SPC) techniques evaluated variation in monthly 90-minute group visits for Spanish- and English-speaking patients during which we reviewed evidence-based recommendations, hosted community speakers and held brief individual encounters using encounter forms with built-in motivational interviewing techniques. RESULTS: On average, four English-speaking patients attended, with 42% of the participants who attended more than one meeting successfully achieving their self-reported goal. On average, nine Spanish-speaking patients attended, with eight (86%) of the participants achieving their goals. Documentation of recorded prevention counselling improved from 15% to 67%. Patients indicated that they found that what they learned is transferable to their everyday 1ives. CONCLUSION: The total number of patient encounters in a clinical session did not dramatically change. Language preference was not a hurdle. Teamwork among patients, providers, staff and community members was a key to success. Group visits improved the amount of prevention counselling and helped patients with limited health literacy achieve their prevention goals.