Community-wide versus school-based targeted deworming for soil-transmitted helminth control in school-aged children in Vietnam: the CoDe-STH cluster-randomised controlled trial

Background

Soil-transmitted helminth (STH) infection control programs typically consist of school-based preventive chemotherapy (PC) targeted to school-aged children. STH reservoirs in untreated community members contribute to ongoing transmission in children. The CoDe-STH (Community Deworming against STH) trial, conducted in Dak Lak province, Vietnam, between October 2019 and November 2020, aimed to determine whether community-wide mass drug administration (MDA) is more effective than school-based targeted PC in reducing STH prevalence and intensity in children.

Methods

In this two-arm cluster randomised controlled trial, 64 primary schools were randomly assigned 1:1 to receive either school-based targeted PC ("school arm") or community-wide MDA ("community arm"). A single dose of albendazole 400 mg was used for deworming. The primary outcome was hookworm prevalence in schoolchildren, measured using quantitative real-time PCR. We also measured infection intensity for Necator americanus only, using qPCR cycle threshold (Ct) values converted into eggs per gram of faeces (EPG). Analysis was by intention to treat. The trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12619000309189).

Findings

The analysis included 4955 children in the school arm and 5093 children in the community arm. N. americanus was the dominant STH species. The relative reduction in hookworm prevalence was not significantly different between the school arm (30.1%, 95% confidence interval [CI] 20.5-36.9) and the community arm (34.6%, 95% CI 19.9-49.4). Due to lower baseline prevalence than expected, the study was underpowered to detect a difference in prevalence reduction between the study arms. The community arm showed significantly greater relative reduction in N. americanus infection intensity (56.0%, 95% CI 39.9-72.1) compared to the school arm (3.4%, 95% CI -24.7 to 31.4). The community arm also showed greater relative reduction in prevalence of moderate-to-heavy intensity (≥2000 EPG) N. americanus infections (81.1%; 95% CI 69.7-92.6) compared to the school arm (39.0%, 95% CI 13.7-64.2).

Interpretation

Although no impact was seen on overall prevalence, community-wide MDA was more effective in lowering N. americanus infection intensity in schoolchildren compared to school-based targeted PC, measured 12 months after one round of albendazole deworming with high coverage.

Funding

National Health and Medical Research Council, Australia (APP1139561).

Cost and cost-effectiveness analysis of mass drug administration compared to school-based targeted preventive chemotherapy for hookworm control in Dak Lak province, Vietnam

Background

School-based targeted preventive chemotherapy (PC), the main strategy for soil-transmitted helminths (STH) control, excludes other at-risk populations including adults and preschool children. Mass drug administration (MDA), covering all age groups, would bring additional health benefits but also requires greater investment. This cost survey and cost-effectiveness analysis compared MDA with school-based targeted PC for STH control in Dak Lak, Vietnam, where STH are endemic.

Methods

A cost survey was conducted in 2020 to estimate the total and per person economic and financial cost of each strategy. Monte Carlo simulation accounted for uncertainty in cost estimates. The primary effectiveness measure was hookworm-related disability-adjusted life years (DALYs) averted, and secondary measures were hookworm infection-years averted and moderate-to-heavy intensity hookworm infection-years averted. A Markov model was used to determine the incremental cost-effectiveness ratio (ICER) of MDA compared to school-based targeted PC using a government payer perspective and a ten-year time horizon. One-way and probabilistic sensitivity analyses (PSA) were performed. Costs are reported in 2020 USD ($).

Findings

The economic cost per person was $0.27 for MDA and $0.43 for school-based targeted PC. MDA in Dak Lak will cost $472,000 per year, while school-based targeted PC will cost $117,000. Over 10 years, MDA is estimated to avert an additional 121,465 DALYs; 4,019,262 hookworm infection-years, and 765,844 moderate-to-heavy intensity hookworm infection-years compared to school-based targeted PC. The ICER was $28.55 per DALY averted; $0.87 per hookworm infection-years averted, and $4.54 per moderate-to-heavy intensity hookworm infection-years averted. MDA was cost-effective in all PSA iterations.

Interpretation

In areas where hookworm predominates and adults suffer a significant burden of infection, MDA is cost effective compared to school based targeted PC and is the best strategy to achieve global targets.

Funding

The project was funded by the National Health and Medical Research Council (NHMRC) of Australia (Project Grant APP1139561) and JPCDT was supported by a UNSW Scientia PhD Scholarship.

Potential prognostic and therapeutic roles for cytokines in breast cancer (Review)

Cytokines are known to have both stimulatory and inhibitory effects on breast cancer growth depending on their relative concentrations and the presence of other modulating factors in the tumour microenvironment. Certain cytokines appear to prevent an effective immune response being mounted, permitting cancer growth, whereas others promote the immune system's anti-tumour capability. Furthermore, the systemic levels of certain cytokines, e.g. IL-6 and IL-18, independently show promising correlations with disease stage and progression. With advances in methods for delivery of cytokines to a tumour site, the enhanced induction of anti-tumour immunity by targeted cytokine release is becoming a realistic option. Here, we review the role of cytokines in the immune response against breast cancer and assess their potential as prognostic indicators and/or use in immune therapy. A literature search was conducted using Medline, restricted to articles published in the English language, using combinations of the following MeSH terms: cytokines, breast cancer, immunology, immunotherapy and interleukins. Focused searches using keywords relevant to the role of cytokines in breast cancer immunology yielded >200 references.