Albeit effective, it is now common knowledge that Long-lasting insecticidal nets (LLINs) and Indoor residual spraying (IRS) will not be sufficient to eliminate malaria in endemic countries. This is because the biological limits of these tools have been defined by the increasing development of insecticide resistance and residual malaria transmission. As a result, there has been advocacy for development and deployment of complementary tools to help drive towards the goal malaria elimination by 2030 as set by World Health Organization (WHO). As a strategy to achieve the set goal, WHO has promoted the employment of Integrated vector management (IVM); the use of a combination of interventions with proven efficacy to tackle malaria transmission.
In line with this strategy, the WHO AFRO II project, which is funded by GEF/UNEP/WHO and implemented by the Ministries of health in Mozambique, Zambia and Zimbabwe and ICIPE has proposed to use house screening in addition to LLINs to tackle malaria transmission in the project countries. It is hypothesised that house screening when added to LLINs will reduce Anopheles mosquito densities and malaria incidence in the study areas compared to areas where there is sole use of LLINs.
Zambia; Malaria transmission in Zambia occurs throughout the year with the peak during the rainy season, between November and April. The major malaria vectors are An. gambiae s.s., An. arabiensis and An. funestus. Indoor residual spraying (IRS) and use of LLINs are the major malaria control inter4eventions used in Zambia and have been employed since early 2000’s. Presidents Malaria initiative (PMI) has supported the Ministry of health to implement IRS is since 2008. Zambia has distributed LLINs through mass campaigns, antenatal clinics and under five-year-old clinics and 24 million LLINs were distributed from 2006 – 2014. Despite these increased efforts in malaria control >4 million cases were confirmed in 2015.
Zimbabwe; Zimbabwe experiences endemic malaria transmission in lowland areas particularly in major river basins. Other malarious areas experience seasonal malaria transmission with a risk of epidemics occurring. Anopheles arabiensis is considered the main vector with a resurgence of Anopheles funestus, recently reported. IRS using DDT is reported as the major malaria control intervention. Winter larviciding has been employed as a malaria control tool. Recently, there has been extensive deployment of LLINs. Despite reduction in malaria burden over the past few years, as a result of these control efforts, Zimbabwe reported >390,000 cases in 2015.
Mozambique; Mozambique experiences endemic malaria transmission with the whole population at risk of malaria. An. funestus and An. gambiae s.s are the major vectors in the country. In the last decade, the malaria control program has implemented large scale IRS programs using DDT and lambda-cyhalothrin in 58 districts protecting 6 to 8 million people every year. Distribution of LLINs was initiated in early 2000s and has been scaled up recently. Malaria remains a major problem in Mozambique with > 7.7 million confirmed cases from health facilities reported in 2015
Despite the malaria control efforts employed in these countries, there is still substantial malaria transmission in these countries. As a result, there is need to supplement the existing control tools in these countries to further reduce malaria transmission and possibly achieve elimination. The AFRO II project therefore aims to evaluate the additional impact of house screening to LLINs on malaria transmission in these countries.