On the cost-effectiveness of insecticide-treated wall liner and indoor residual spraying as additions to insecticide treated bed nets to prevent malaria: findings from cluster randomized trials in Tanzania.

BACKGROUND: Despite widespread use of long-lasting insecticidal nets (LLINs) and other tools, malaria caused 409,000 deaths worldwide in 2019. While indoor residual spraying (IRS) is an effective supplement, IRS is moderately expensive and logistically challenging. In endemic areas, IRS requires yearly application just before the main rainy season and potential interim reapplications. A new technology, insecticide-treated wall liner (ITWL), might overcome these challenges. METHODS: We conducted a 44-cluster two-arm randomized controlled trial in Muheza, Tanzania from 2015 to 2016 to evaluate the cost and efficacy of a non-pyrethroid ITWL to supplement LLINs, analyzing operational changes over three installation phases. The estimated efficacy (with 95% confidence intervals) of IRS as a supplement to LLINs came mainly from a published randomized trial in Muleba, Tanzania. We obtained financial costs of IRS from published reports and conducted a household survey of a similar IRS program near Muleba to determine household costs. The costs of ITWL were amortized over its 4-year expected lifetime and converted to 2019 US dollars using Tanzania's GDP deflator and market exchange rates. RESULTS: Operational improvements from phases 1 to 3 raised ITWL coverage from 35.1 to 67.1% of initially targeted households while reducing economic cost from $34.18 to $30.56 per person covered. However, 90 days after installing ITWL in 5666 households, the randomized trial was terminated prematurely because cone bioassay tests showed that ITWL no longer killed mosquitoes and therefore could not prevent malaria. The ITWL cost $10.11 per person per year compared to $5.69 for IRS. With an efficacy of 57% (3-81%), IRS averted 1162 (61-1651) disability-adjusted life years (DALYs) per 100,000 population yearly. Its incremental cost-effectiveness ratio (ICER) per DALY averted was $490 (45% of Tanzania's per capita gross national income). CONCLUSIONS: These findings provide design specifications for future ITWL development and implementation. It would need to be efficacious and more effective and/or less costly than IRS, so more persons could be protected with a given budget. The durability of a previous ITWL, progress in non-pyrethroid tools, economies of scale and competition (as occurred with LLINs), strengthened community engagement, and more efficient installation and management procedures all offer promise of achieving these goals. Therefore, ITWLs merit ongoing study. FIRST POSTED: 2015 ( NCT02533336 ).

"We are doctors": Drivers of animal health practices among Maasai pastoralists and implications for antimicrobial use and antimicrobial resistance.

Animal health service providers can play an important role in limiting drug resistance by promoting responsible and prudent use of veterinary drugs. Recognizing this potential, international agencies and governments have called for these providers to receive drug stewardship training, particularly providers in low- and middle-income countries where top-down regulations (e.g., national regulation of veterinary prescriptions) are largely unfeasible. The success of these stewardship trainings to promote responsible and prudent use will depend on many factors, including understanding how livestock-keeping communities currently interact with animal health service providers. Here, we use a mixed methods approach to identify and understand animal health seeking practices among Maasai pastoralists in Tanzania. Combining qualitative interviews (N = 31) and structured surveys (N = 195), we show the majority of Maasai respondents (≈80 %) do not frequently consult animal health service providers with most relying on advice from family and friends. Logistic regression models of health seeking practices find that increasing age, education, observance of treatment failure, and herd disease burdens are associated with greater odds of seeking out health services. Quantitative results were supported by data from focus group discussions and in-depth interviews that showed Maasai view animal health service providers as measures of last resort, whose input is largely sought after self-treatment with veterinary drugs fail. We argue patterns of animal health seeking among the Maasai are partially the consequence of their high confidence in their own abilities in livestock disease and treatment and generally low confidence in the skills of animal health service providers. We link this high sense of self-efficacy to the culturally engrained process by which Maasai develop mastery in animal health and how the roles and norms in Maasai culture surrounding animal health influence Maasai perceptions of animal health professionals. Our results highlight the need for more research to understand Maasai perceptions of animal health service providers as well as the knowledge, attitudes, and practices of these providers. Finally, our study emphasizes that the success of drug stewardship trainings will require efforts to first understand the cultural and historical contexts driving health seeking practices that impact perceptions of animal health service providers and animal health practices more generally.