Disease control programmes rely on LLINs and IRS as the only two validated interventions. Several other interventions such as larviciding are practiced but their effectiveness in disease control, and the circumstances under which they can be effective may be limited. No effective new paradigm for vector control has been adopted since the introduction of insecticide treated nets in the mid 1980s, and it is interesting to note that this innovation in nets was enabled by the advent of the pyrethroid insecticide chemistry.
IVCC plans to identify and develop an intervention that can be delivered through the consumer product channel that is epidemiologically effective. Our Industrial partners have already made a number of proposals to IVCC for products that may suit this paradigm. These proposals ranging from novel emanaters or low cost insecticide vapour diffusion products to novel distribution models based on franchising insecticide treatment.
One such programme using insecticide treated wall hangings and curtains is being tested in the dengue, Casa Segura, paradigm programme. IVCC has started to engage the key stakeholders in the design of experiments for paradigm verification (entomologists, policy advisors, industrial partners and statisticians) through a series of consultation workshops. Key areas that need to be experimentally verified include evidence of epidemiological impact, product efficacy, user compliance and distribution efficiency.
After further consultation, IVCC will plan a coordinated set of trials to establish these critical success factors for a consumer paradigm product and solicit candidate consumer oriented products from the insecticide industry to test in this intervention.
Such trials span a huge range of expertise from epidemiology and entomology to compliance and delivery, a span which only IVCC is positioned to deliver in a coordinated manner. Key outcomes of new paradigm consultation so far include:
- The importance of user acceptability/compliance trials early in the design process.
- The increasing difficulty of executing efficacy trials in an environment of decreasing incidence, and hence the large numbers of subjects required to achieve statistical significance with weak indicators.
- The large anticipated scale and cost of these trials. The workshop concluded that 5 randomised controlled trials, coordinated to test a variety of environmental, transmission and cultural settings was required.
The testing of new paradigms is a task well suited to execution by a consortium where coordinated statistical design can be married to diverse trials sites, transmission intensities and cultural variations.