Discovery of Knock-Down Resistance in the Major African Malaria Vector Anopheles funestus.

A major insecticide resistance mechanism in insect pests is knock-down resistance (kdr) caused by mutations in the voltage-gated sodium channel (Vgsc) gene. Despite being common in most malaria Anopheles vector species, kdr mutations have never been observed in Anopheles funestus, the principal malaria vector in Eastern and Southern Africa, with resistance mainly being conferred by detoxification enzymes. In a parallel study, we monitored 10 populations of An.

Semi-field evaluation of aquatic predators for the control of Anopheles funestus in rural south-eastern Tanzania.

Background: Biological control is a promising alternative or complementary approach for controlling vector populations in response to the spread of insecticide resistance in malaria vectors. This study evaluated the efficacy of three selected potential predators on the density and fitness parameters of Anopheles funestus larvae in rural Tanzania.

Methods: Common predator families Aeshnidae (dragonflies), Coenagrionidae (damselflies), and Notonectidae (backswimmers) and An.

Entomological survey of sibling species in the Anopheles funestus group in Tanzania confirms the role of Anopheles parensis as a secondary malaria vector.

Background: Malaria transmission in Tanzania is driven by mosquitoes of the Anopheles gambiae complex and Anopheles funestus group. The latter includes An. funestus s.

Discovery of knock-down resistance in the major African malaria vector .

A major mechanism of insecticide resistance in insect pests is knock-down resistance () caused by mutations in the voltage-gated sodium channel () gene. Despite being common in most malaria vector species, mutations have never been observed in , the principal malaria vector in Eastern and Southern Africa. While monitoring 10 populations of in Tanzania, we unexpectedly found resistance to DDT, a banned insecticide, in one location.

Challenges of proper disposal of old long-lasting insecticidal nets and its alternative uses in rural south-eastern Tanzania.

Introduction: Insecticide-treated nets (ITNs), specifically long-lasting insecticidal nets (LLINs), are the most commonly used, scalable, and cost-effective tools for controlling malaria transmission in sub-Saharan Africa. However, the multiple alternative uses of retired LLINs have been associated with poor disposal practices. The World Health Organization (WHO) has provided guidelines and recommendations for the proper management of worn-out LLINs.

Exploring the potential of village community banking as a community-based financing system for house improvements and malaria vector control in rural Tanzania.

House improvement is associated with remarkable reductions in indoor mosquito bites and disease incidences, even in typical rural houses. However, its exploitation remains extremely poor in Tanzania and other endemic countries due to limited financial resources. Nevertheless, village community banks (VICOBA), practiced in Tanzania for nearly two decades, have proven to provide financial services to rural communities that would otherwise not be able to get them from formal financial institutions.

Geospatial based model for malaria risk prediction in Kilombero valley, South-eastern, Tanzania.

Background: Malaria continues to pose a major public health challenge in tropical regions. Despite significant efforts to control malaria in Tanzania, there are still residual transmission cases. Unfortunately, little is known about where these residual malaria transmission cases occur and how they spread.

Common predators and factors influencing their abundance in Anopheles funestus aquatic habitats in rural south-eastern Tanzania.

Background: The role of larval predators in regulating the Anopheles funestus population in various malaria-endemic countries remains relatively unknown. This study aimed to investigate the common predators that co-exist with Anopheles funestus group larvae and evaluate factors that influence their abundance in rural south-eastern Tanzania.

Methods: Mosquito larvae and predators were sampled concurrently using standard dipper (350 ml) or 10 L bucket in previously identified aquatic habitats in selected villages in southern Tanzania.

Effects of vegetation densities on the performance of attractive targeted sugar baits (ATSBs) for malaria vector control: a semi-field study.

Background: Attractive targeted sugar baits (ATSBs) control sugar-feeding mosquitoes with oral toxicants, and may effectively complement core malaria interventions, such as insecticide-treated nets even where pyrethroid-resistance is widespread. The technology is particularly efficacious in arid and semi-arid areas. However, their performance remains poorly-understood in tropical areas with year-round malaria transmission, and where the abundant vegetation constitutes competitive sugar sources for mosquitoes.

Corrigendum to "Persistently high proportions of -infected mosquitoes in two villages in the Kilombero valley, South-Eastern Tanzania" [Parasite Epidemiology and Control 18 (2022) e00264].

[This corrects the article DOI: 10.1016/j.parepi.

Relationships between biological age, distance from aquatic habitats and pyrethroid resistance status of Anopheles funestus mosquitoes in south-eastern Tanzania.

Background: Malaria transmission can be highly heterogeneous between and within localities, and is influenced by factors such as survival and biting frequencies of Anopheles mosquitoes. This study investigated the relationships between the biological age, distance from aquatic habitats and pyrethroid resistance status of Anopheles funestus mosquitoes, which currently dominate malaria transmission in south-east Tanzania. The study also examined how such relationships may influence malaria transmission and control.

Participatory development of practical, affordable, insecticide-treated mosquito proofing for a range of housing designs in rural southern Tanzania.

Background: Insecticidal mosquito-proof netting screens could combine the best features of insecticide-treated nets (ITNs) and indoor residual spraying (IRS), the two most important front line vector control interventions in Africa today, and also overcome the most important limitations of these methods. This study engaged members of a rural Tanzanian community in developing and evaluating simple, affordable and scalable procedures for installing readily available screening materials on eave gaps and windows of their own houses, and then treating those screens with a widely used IRS formulation of the organophosphate insecticide pirimiphos-methyl (PM).

Methods: A cohort of 54 households recruited upon consent, following which the structural features and occupant demographics of their houses were surveyed.

Persistently high proportions of -infected mosquitoes in two villages in the Kilombero valley, South-Eastern Tanzania.

Background: In south-eastern Tanzania where insecticide-treated nets have been widely used for >20 years, malaria transmission has greatly reduced but remains highly heterogenous over small distances. This study investigated the seasonal prevalence of sporozoite infections in the two main malaria vector species, and for 34 months, starting January 2018 to November 2020.

Methods: Adult mosquitoes were collected using CDC-light traps and Prokopack aspirators inside local houses in Igumbiro and Sululu villages, where earlier surveys had found very high densities of .

Observing the distribution of mosquito bites on humans to inform personal protection measures against malaria and dengue vectors.

Background: Understanding mosquito biting behaviours is important for designing and evaluating protection methods against nuisance biting and mosquito-borne diseases (e.g. dengue, malaria and zika).

Insecticide-treated eave ribbons for malaria vector control in low-income communities.

Supplementary tools are required to address the limitations of insecticide-treated nets (ITNs) and indoor residual spraying (IRS), which are currently the core vector control methods against malaria in Africa. The eave ribbons technology exploits the natural house-entry behaviours of major malaria vectors to deliver mosquitocidal or repellent actives around eave spaces through which the Anopheles mosquitoes usually enter human dwellings. They confer protection by preventing biting indoors and in the peri-domestic outdoor spaces, and also killing a significant proportion of the mosquitoes.

Wild populations of malaria vectors can mate both inside and outside human dwellings.

Background: Wild populations of Anopheles mosquitoes are generally thought to mate outdoors in swarms, although once colonized, they also mate readily inside laboratory cages. This study investigated whether the malaria vectors Anopheles funestus and Anopheles arabiensis can also naturally mate inside human dwellings.

Method: Mosquitoes were sampled from three volunteer-occupied experimental huts in a rural Tanzanian village at 6:00 p.

Fine-scale distribution of malaria mosquitoes biting or resting outside human dwellings in three low-altitude Tanzanian villages.

Background: While malaria transmission in Africa still happens primarily inside houses, there is a substantial proportion of Anopheles mosquitoes that bite or rest outdoors. This situation may compromise the performance of indoor insecticidal interventions such as insecticide-treated nets (ITNs). This study investigated the distribution of malaria mosquitoes biting or resting outside dwellings in three low-altitude villages in south-eastern Tanzania.

Aquatic habitats of the malaria vector Anopheles funestus in rural south-eastern Tanzania.

Background: In rural south-eastern Tanzania, Anopheles funestus is a major malaria vector, and has been implicated in nearly 90% of all infective bites. Unfortunately, little is known about the natural ecological requirements and survival strategies of this mosquito species.

Methods: Potential mosquito aquatic habitats were systematically searched along 1000 m transects from the centres of six villages in south-eastern Tanzania.