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Abstract Background Non-communicable diseases (NCDs) are the world’s growing cause of preventable illness, disability, morbidity, and mortality which account for 71% of deaths. The aim of this study was to determine the factors associated with mortality from NCDs among persons aged 15 years and above in Zambia. Methodology The study used data from Sample Vital Registration with Verbal Autopsy (SAVVY) 2015/16 (Zambia). A total of 3529 Verbal Autopsy were completed in the study, with only 2599 of death where among people aged 15 years and above. Three-level data analysis was applied; univariate analysis, bivariate analysis, and multivariate analysis (binary logistic regression). Findings The overall number of deaths from NCDs was 28.81%. Stratified analysis by gender showed that deaths from NCDs were higher among women (32.60%) as compared to men (26.25%). Among all persons, dying from NCDs was associated with tobacco use, age, and education. Tobacco use was negatively associated with mortality from NCDs (adjusted odds ratio [aOR] = 0.68; 95% confidence interval [CI]: 0.48–0.98). Age was positively associated with the odds of dying from NCDs among persons aged 45–59 years (aOR = 3.87, 95% CI: 2.13–7.01), 60–74 years (aOR = 12.05, 95% CI: 6.44–22.55), and 75 + years (aOR = 15.16, 95% CI: 7.93–28.97). The likelihood of dying from NCDs was higher among persons with secondary education as compared to those with no education (aOR = 1.93, 95% CI: 1.11–3.33). Conclusion The findings from this study suggest that public health interventions targeting NCDs need to consider behavioural factors, especially tobacco use which exposes people to second-hand smoke. We also recommend large-scale national-level studies to further examine the contribution of each factor leading to mortality from NCDs.

Abstract Background Pyrethroid resistance observed in populations of malaria vectors is widespread in Ethiopia and could potentially compromise the effectiveness of insecticide-based malaria vector control interventions. In this study, the impact of combining indoor residual spraying (IRS) and insecticide-treated nets (ITNs) on mosquito behaviour and mortality was evaluated using experimental huts. Methods A Latin Square Design was employed using six experimental huts to collect entomological data. Human volunteers slept in huts with different types of nets (pyrethroid-only net, PBO net, and untreated net) either with or without IRS (Actellic 300CS). The hut with no IRS and an untreated net served as a negative control. The study was conducted for a total of 54 nights. Both alive and dead mosquitoes were collected from inside nets, in the central rooms and verandah the following morning. Data were analysed using Stata/SE 14.0 software package (College Station, TX, USA). Results The personal protection rate of huts with PermaNet® 2.0 alone and PermaNet® 3.0 alone was 33.3% and 50%, respectively. The mean killing effect of huts with PermaNet® 2.0 alone and PermaNet® 3.0 alone was 2% and 49%, respectively. Huts with PermaNet® 2.0 alone and PermaNet® 3.0 alone demonstrated significantly higher excito-repellency than the control hut. However, mosquito mortality in the hut with IRS + untreated net, hut with IRS + PermaNet® 2.0 and hut with IRS + PermaNet® 3.0 were not significantly different from each other (p > 0.05). Additionally, pre-exposure of both the susceptible Anopheles arabiensis laboratory strain and wild Anopheles gambiae sensu lato to PBO in the cone bioassay tests of Actellic 300CS sprayed surfaces did not reduce mosquito mortality when compared to mortality without pre-exposure to PBO. Conclusion Mosquito mortality rates from the huts with IRS alone were similar to mosquito mortality rates from the huts with the combination of vector control intervention tools (IRS + ITNs) and mosquito mortality rates from huts with PBO nets alone were significantly higher than huts with pyrethroid-only nets. The findings of this study help inform studies to be conducted under field condition for decision-making for future selection of cost-effective vector control intervention tools. Graphical Abstract

Abstract Background The recent detection of the South Asian malaria vector Anopheles stephensi in the Horn of Africa (HOA) raises concerns about the impact of this mosquito on malaria transmission in the region. Analysis of An. stephensi genetic diversity and population structure can provide insight into the history of the mosquito in the HOA to improve predictions of future spread. We investigated the genetic diversity of An. stephensi in eastern Ethiopia, where detection suggests a range expansion into this region, in order to understand the history of this invasive population. Methods We sequenced the cytochrome oxidase subunit I (COI) and cytochrome B gene (CytB) in 187 An. stephensi collected from 10 sites in Ethiopia in 2018. Population genetic, phylogenetic, and minimum spanning network analyses were conducted for Ethiopian sequences. Molecular identification of blood meal sources was also performed using universal vertebrate CytB sequencing. Results Six An. stephensi COI-CytB haplotypes were observed, with the highest number of haplotypes in the northeastern sites (Semera, Bati, and Gewana towns) relative to the southeastern sites (Kebridehar, Godey, and Degehabur) in eastern Ethiopia. We observed population differentiation, with the highest differentiation between the northeastern sites compared to central sites (Erer Gota, Dire Dawa, and Awash Sebat Kilo) and the southeastern sites. Phylogenetic and network analysis revealed that the HOA An. stephensi are more genetically similar to An. stephensi from southern Asia than from the Arabian Peninsula. Finally, molecular blood meal analysis revealed evidence of feeding on cows, goats, dogs, and humans, as well as evidence of multiple (mixed) blood meals. Conclusion We show that An. stephensi is genetically diverse in Ethiopia and with evidence of geographical structure. Variation in the level of diversity supports the hypothesis for a more recent introduction of An. stephensi into southeastern Ethiopia relative to the northeastern region. We also find evidence that supports the hypothesis that HOA An. stephensi populations originate from South Asia rather than the Arabian Peninsula. The evidence of both zoophagic and anthropophagic feeding support the need for additional investigation into the potential for livestock movement to play a role in vector spread in this region. Graphical Abstract

Abstract Background Anopheles stephensi, an invasive malaria vector, was first detected in Africa nearly 10 years ago. After the initial finding in Djibouti, it has subsequently been found in Ethiopia, Sudan and Somalia. To better inform policies and vector control decisions, it is important to understand the distribution, bionomics, insecticide susceptibility, and transmission potential of An. stephensi. These aspects were studied as part of routine entomological monitoring in Ethiopia between 2018 and 2020. Methods Adult mosquitoes were collected using human landing collections, pyrethrum spray catches, CDC light traps, animal-baited tent traps, resting boxes, and manual aspiration from animal shelters. Larvae were collected using hand-held dippers. The source of blood in blood-fed mosquitoes and the presence of sporozoites was assessed through enzyme-linked immunosorbent assays (ELISA). Insecticide susceptibility was assessed for pyrethroids, organophosphates and carbamates. Results Adult An. stephensi were collected with aspiration, black resting boxes, and animal-baited traps collecting the highest numbers of mosquitoes. Although sampling efforts were geographically widespread, An. stephensi larvae were collected in urban and rural sites in eastern Ethiopia, but An. stephensi larvae were not found in western Ethiopian sites. Blood-meal analysis revealed a high proportion of blood meals that were taken from goats, and only a small proportion from humans. Plasmodium vivax was detected in wild-collected An. stephensi. High levels of insecticide resistance were detected to pyrethroids, carbamates and organophosphates. Pre-exposure to piperonyl butoxide increased susceptibility to pyrethroids. Larvae were found to be susceptible to temephos. Conclusions Understanding the bionomics, insecticide susceptibility and distribution of An. stephensi will improve the quality of a national response in Ethiopia and provide additional information on populations of this invasive species in Africa. Further work is needed to understand the role that An. stephensi will have in Plasmodium transmission and malaria case incidence. While additional data are being collected, national programmes can use the available data to formulate and operationalize national strategies against the threat of An. stephensi.

Anopheles stephensi mosquitoes, efficient vectors in parts of Asia and Africa, were found in 75.3% of water sources surveyed and contributed to 80.9% of wild-caught Anopheles mosquitoes in Awash Sebat Kilo, Ethiopia. High susceptibility of these mosquitoes to Plasmodium falciparum and vivax infection presents a challenge for malaria control in the Horn of Africa.

Abstract Background The recent detection of the South Asian malaria vector Anopheles stephensi in Ethiopia and other regions in the Horn of Africa has raised concerns about its potential impact on malaria transmission. We report here the findings of a survey for this species in eastern Ethiopia using both morphological and molecular methods for species identification. Methods Adult and larval/pupal collections were conducted at ten sites in eastern Ethiopia and Anopheles specimens were identified using standard morphological keys and genetic analysis. Results In total, 2231 morphologically identified An. stephensi were collected. A molecular approach incorporating both PCR endpoint assay and sequencing of portions of the internal transcribed spacer 2 (ITS2) and cytochrome c oxidase subunit 1 (cox1) loci confirmed the identity of the An. stephensi in most cases (119/124 of the morphologically identified An. stephensi confirmed molecularly). Additionally, we observed Aedes aegypti larvae and pupae at many of the An. stephensi larval habitats. Conclusions Our findings show that An. stephensi is widely distributed in eastern Ethiopia and highlight the need for further surveillance in the southern, western and northern parts of the country and throughout the Horn of Africa.

Abstract Background Indoor residual spraying (IRS) is being implemented as one of the malaria prevention methods in the Northern Region of Ghana. Changes in longevity, sporozoite and entomological inoculation rates (EIRs) of major malaria vectors were monitored to assess the impact of IRS in selected districts. Methods Monthly human landing catches (HLCs) were used to collect mosquitoes from sentinel sites in three adjacent districts between July 2009 and December 2014: Savelugu Nanton (SND) where IRS had been implemented from 2008 to 2014; Tolon Kumbungu (TKD) where IRS had been implemented between 2008 and 2012 and Tamale Metropolis (TML) with no history of IRS. Mosquitoes were morphologically identified to species level and into sibling species, using PCR. Samples of Anopheles gambiae sensu lato (s.l.) were examined for parity and infectivity. EIR was calculated from biting and infectivity rates of malaria vectors. Results Parity rates of An. gambiae s.l. decreased significantly (p