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Background Access to human hosts by Anopheles mosquitoes is a key determinant of vectorial capacity for malaria, but it can be limited by use of long-lasting insecticidal nets (LLINs). In Malawi, pyrethroid-treated LLINs with and without the synergist piperonyl butoxide (PBO) were distributed to control malaria. This study investigated the blood-feeding patterns of malaria vectors and whether LLINs containing pyrethroid and PBO led to a reduction of human blood feeding than those containing only pyrethroids. Methods Mosquitoes were sampled inside houses from May 2019 through April 2020 by aspiration, pyrethrum spray catch, and light trap methods in two sites. One site (Namanolo, Balaka district) had LLINs containing only pyrethroids whereas the other (Ntaja, Machinga district) had LLINs with both pyrethroids and PBO. Anopheles species, their blood-meal host, and infection with Plasmodium falciparum were determined using PCR methods. Results A total of 6585 female Anopheles were sampled in 203 houses. Of these, 633 (9.6%) were blood-fed mosquitoes comprising of 279 (44.1%) Anopheles arabiensis, 103 (16.3%) Anopheles gambiae 212 (33.5), Anopheles funestus, 2 (0.3%), Anopheles parensis and 37 (5.8%) were unidentified Anopheles spp. Blood meal hosts were successfully identified for 85.5% (n = 541) of the blood-fed mosquitoes, of which 436 (81.0%) were human blood meals, 28 (5.2%) were goats, 11 (2.0%) were dogs, 60 (11.1%) were mixed goat-human blood meals, 5 (0.9%) were dog–human, and 1 was a mixed dog-goat. Human blood index (fraction of blood meals that were humans) was significantly higher in Namanolo (0.96) than Ntaja (0.89). Even though human blood index was high, goats were over-selected than humans after accounting for relative abundance of both hosts. The number of infectious Anopheles bites per person-year was 44 in Namanolo and 22 in Ntaja. Conclusion Although LLINs with PBO PBO may have reduced human blood feeding, access to humans was extremely high despite high LLIN ownership and usage rates in both sites. This finding could explain persistently high rates of malaria infections in Malawi. However, this study had one village for each net type, thus the observed differences may have been a result of other factors present in each village.

ObjectivesDevelopment of a Community Engagement Package composed of (1) database of community engagement (CE) experiences from different contexts, (2) CE learning package of lessons and tools presented as online modules, and (3) CE workshop package for identifying CE experiences to enrich the CE database and ensure regular update of learning resources. The package aims to guide practitioners to promote local action and enhance skills for CE.Setting and participantsThe packages were co-created with diverse teams from WHO, Social Innovation in Health Initiative, UNICEF, community practitioners, and other partners providing synergistic contributions and bridging existing silos.MethodsThe design process of the package was anchored on CE principles. Literature search was performed using standardised search terms through global and regional databases. Interviews with CE practitioners were also conducted.ResultsA total of 356 cases were found to fit the inclusion criteria and proceeded to data extraction and thematic analysis. Themes were organised according to rationale, key points and insights, facilitators of CE and barriers to CE. Principles and standards of CE in various contexts served as a foundation for the CE learning package. The package comprises four modules organised by major themes such as mobilising communities, strengthening health systems, CE in health emergencies and CE as a driver for health equity.ConclusionAfter pilot implementation, tools and resources were made available for training and continuous collection of novel CE lessons and experiences from diverse socio-geographical contexts.

In Africa four randomized trials found a reduction in deaths among children under 5 years of age with the use of insecticide-treated nets (ITNs) (three trials) or insecticide-treated curtains. These results are encouraging; however they pose several additional issues. First is the issue of translating efficacy of the scientific trial into effectiveness which means success when implemented as a health-service program. Although results of the KINET project in the Ifakara district in promoting ITNs through social marketing have been positive and are encouraging the question of whether the methods can work elsewhere in Africa remains. Another question for the promoters of ITNs is posed in the claim that reducing the force of infection in some human diseases might similarly increase the incidence of the disease and its mortality. In terms of malaria reducing infection rates could possibly lead to an increase in the frequency of the disease. However ITN programs should proceed in spite of such a possibility. Monitoring must be conducted in populations subjected to a variety of transmission patterns so that any adverse consequences can be identified and tackled.