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The use of Grewia tenax and Albizia anthelmintica in treating different ailments is attracting significant attention as a primary health care option in Namibia. This study aims to document their ethnobotanical uses, phytochemical composition, antioxidant, and antibacterial activity against multidrug-resistant Streptococcus pneumonia, Klebsiella pneumonia, and Staphylococcus aureus. The ethnobotanical uses of G. tenax and A. anthelmintica in treating respiratory conditions were documented. Organic (ethyl acetate) and aqueous extracts were screened for phytochemical composition using the thin-layer chromatography method. The total phenol content was determined using the Folin and Ciocalteu reagent method. In vitro antioxidant activity was based on the scavenging activity of the stable 1, 1-diphenyl 2-picrylhyorazyl free radical. Antibacterial activity of extracts (200.0 µg/ml) and antibiotics was determined by the disc diffusion method. G. tenax and A. anthelmintica are commonly used to treat pneumonic symptoms. Steam inhalation and decoction are the most common methods used in preparing remedies. While alkaloid, flavonoid, and coumarins were detected in all extracts, organic extract of A. anthelmintica showed higher total phenol content of 28.5 ± 0. 5 mg GAE/g. G. tenax organic extract showed higher in-vitro antioxidant activity of 83.3±0.1%. The pathogens showed resistance to 10 µg of penicillin G, and Co-Trimoxazol, however, A. anthelmintica organic twig extracts inhibited the growth of the bacteria with average inhibition ranging between 17.5±0.6 - 20.7±0.6, mm and a minimum inhibitory concentration of 50.0 µg/mL. These findings are the first to report on the ethnomedicine of G. tenax and A. anthelmintica in Namibia and their effectiveness in killing pneumonia-causing bacteria. Key words: Phytochemical screening, total phenol content, antioxidant activity, antibacterial activity, pneumonia, antibiotic resistance, G. tenax, A. anthelmintica.

Background Identifying efficient and effective strategies to reach and monitor populations at greatest risk of malaria in low-transmission settings is a key challenge for malaria elimination. In Namibia’s Zambezi Region, transmission is ongoing yet its drivers remain poorly understood. A growing literature suggests that night-time social activities may lead to malaria exposure that is beyond the reach of conventional preventive interventions, such as insecticide treated bed nets and indoor residual spraying. Methods Formative research was conducted with community members in March, 2015 in the catchment areas of six randomly selected health facilities in the western Zambezi Region to identify night-time locations where large numbers of individuals regularly congregate. Using time-location sampling, a survey was conducted between March and May, 2015 at community-identified venues (bars and evening church services) to develop representative estimates of the prevalence of parasite infection and risk factors among venue-goers. Results When compared to a contemporaneous household survey of the general population aged 15 and older (N = 1160), venue-goers (N = 480) were more likely to have spent the night away from their home recently (17.3% vs. 8.9%, P = 0.008), report recent fever (65.2% vs. 36.9%, P

In areas of low and unstable transmission, malaria cases occur in populations with lower access to malaria services and interventions, and in groups with specific malaria risk exposures often away from the household. In support of the Namibian National Vector Borne Disease Program’s drive to better target interventions based upon risk, we implemented a health facility-based case control study aimed to identify risk factors for symptomatic malaria in Zambezi Region, northern Namibia. A total of 770 febrile individuals reporting to 6 health facilities and testing positive by rapid diagnostic test (RDT) between February 2015 and April 2016 were recruited as cases; 641 febrile individuals testing negative by RDT at the same health facilities through June 2016 were recruited as controls. Data on socio-demographics, housing construction, overnight travel, use of malaria prevention and outdoor behaviors at night were collected through interview and recorded on a tablet-based questionnaire. Remotely-sensed environmental data were extracted for geo-located village residence locations. Multivariable logistic regression was conducted to identify risk factors and latent class analyses (LCA) used to identify and characterize high-risk subgroups. The majority of participants (87% of cases and 69% of controls) were recruited during the 2016 transmission season, an outbreak year in Southern Africa. After adjustment, cases were more likely to be cattle herders (Adjusted Odds Ratio (aOR): 4.46 95%CI 1.05–18.96), members of the police or other security personnel (aOR: 4.60 95%CI: 1.16–18.16), and pensioners/unemployed persons (aOR: 2.25 95%CI 1.24–4.08), compared to agricultural workers (most common category). Children (aOR 2.28 95%CI 1.13–4.59) and self-identified students were at higher risk of malaria (aOR: 4.32 95%CI 2.31–8.10). Other actionable risk factors for malaria included housing and behavioral characteristics, including traditional home construction and sleeping in an open structure (versus modern structure: aOR: 2.01 95%CI 1.45–2.79 and aOR: 4.76 95%CI: 2.14–10.57); cross border travel in the prior 30 days (aOR: 10.55 95%CI 2.94–37.84); and outdoor agricultural work at night (aOR: 2.09 95%CI 1.12–3.87). Malaria preventive activities were all protective and included personal use of an insecticide treated net (ITN) (aOR: 0.61 95%CI 0.42–0.87), adequate household ITN coverage (aOR: 0.63 95%CI 0.42–0.94), and household indoor residual spraying (IRS) in the past year (versus never sprayed: (aOR: 0.63 95%CI 0.44–0.90). A number of environmental factors were associated with increased risk of malaria, including lower temperatures, higher rainfall and increased vegetation for the 30 days prior to diagnosis and residing more than 5 minutes from a health facility. LCA identified six classes of cases, with class membership strongly correlated with occupation, age and select behavioral risk factors. Use of ITNs and IRS coverage was similarly low across classes. For malaria elimination these high-risk groups will need targeted and tailored intervention strategies, for example, by implementing alternative delivery methods of interventions through schools and worksites, as well as the use of specific interventions that address outdoor transmission.

Due to challenges in measuring changes in malaria in low transmission settings, serology is increasingly being used to complement clinical and parasitological surveillance. Longitudinal cohort studies have shown serological markers, such as Etramp5.Ag1, to be particularly discriminatory of spatio-temporal differences in malaria transmission. However, these markers have yet to be used as endpoints in intervention trials. This study is an extended analysis of a 2017 cluster randomised trial conducted in Zambezi Region, Namibia, evaluating the effectiveness of reactive focal mass drug administration (rfMDA) and reactive vector control (RAVC). A panel of eight serological markers of Plasmodium falciparum infection - Etramp5.Ag1, GEXP18, HSP40.Ag1, Rh2.2030, EBA175, PfMSP119, PfAMA1, and PfGLURP.R2 - was used on a multiplex immunoassay to measure population antibody responses as trial endpoints.Reductions in sero-prevalence to antigens Etramp.Ag1, PfMSP119, Rh2.2030, and PfAMA1 were observed in study arms combining rfMDA and RAVC, but only effects for Etramp5.Ag1 were statistically significant. Etramp5.Ag1 sero-prevalence was significantly lower in all intervention arms. Compared to the reference arms, adjusted Etramp5.Ag1 prevalence ratio (aPR) was 0.77 (95%CI 0.65 – 0.90, pThe use of serological endpoints to evaluate trial outcomes was comparable to qPCR and measured effect size with improved precision. Serology has clear application in cluster randomised trials, particularly in settings where measuring clinical incidence or infection is less reliable due to seasonal fluctuations, limitations in health care seeking, or incomplete testing and reporting.Key questionsWhat is already known?▪Numerous serological studies across sub-Saharan Africa have found that malaria-specific antibody responses are highly correlated with malaria transmission.▪Serology is increasingly being used to complement traditional malaria surveillance data in settings where clinical or parasitological measures of incidence or infection may be less reliable due to fluctuations in parasite densities, limitations in health care seeking, or incomplete testing and reporting.▪The identification of new serological markers associated with recent malaria exposure hold promise as measures of malaria incidence. In previous longitudinal cohort studies, Etramp5.Ag1 has been shown to be a discriminatory serological marker capable of detecting spatio-temporal differences in malaria transmission. However, these markers have never been formally used as endpoints in a malaria cluster randomised trial.What are the new findings?▪This study is the first application of serological endpoints in a malaria cluster randomised trial. Using a multiplexed immunoassay, a panel of sero-incidence markers of recent malaria exposure were used to evaluate the effectiveness of reactive focal mass drug administration (rfMDA) and reactive focal vector control (RAVC) compared to reactive case detection (standard of care) to reduce malaria transmission.▪Cluster-level antibody responses were significantly lower in all intervention arms compared to control, and effect sizes were measured with greater study power than other trial endpoints such as quantitative polymerase chain reaction (qPCR) parasite prevalence.What do the new findings imply?▪The findings from this study, together with ongoing innovations in assay design and multi-disease platforms, illustrate the potential application of serological markers as endpoints in cluster randomised trials. The use of serological endpoints can help achieve trial efficiencies, such as reduced sample size, particularly in low transmission settings or multi-intervention trials where measuring differences between study arms may be challenging with clinical or parasitological endpoints alone.

Background In Namibia, as in many malaria elimination settings, reactive case detection (RACD), or malaria testing and treatment around index cases, is a standard intervention. Reactive focal mass drug administration (rfMDA), or treatment without testing, and reactive focal vector control (RAVC) in the form of indoor residual spraying, are alternative or adjunctive interventions, but there are limited data regarding their community acceptability. Methods A parent trial aimed to compare the effectiveness of rfMDA versus RACD, RAVC versus no RAVC, and rfMDA + RAVC versus RACD only. To assess acceptability of these interventions, a mixed-methods study was conducted using key informant interviews (KIIs) and focus group discussions (FGDs) in three rounds (pre-trial and in years 1 and 2 of the trial), and an endline survey. Results In total, 17 KIIs, 49 FGDs were conducted with 449 people over three annual rounds of qualitative data collection. Pre-trial, community members more accurately predicted the level of community acceptability than key stakeholders. Throughout the trial, key participant motivators included: malaria risk perception, access to free community-based healthcare and IRS, and community education by respectful study teams. RACD or rfMDA were offered to 1372 and 8948 individuals in years 1 and 2, respectively, and refusal rates were low ( Conclusions Communities found both reactive focal interventions and their combination highly acceptable. Engaging communities and centering and incorporating their perspectives and experiences during design, implementation, and evaluation of this community-based intervention was critical for optimizing study engagement.

Summary Background In low malaria-endemic settings, screening and treatment of individuals in close proximity to index cases, also known as reactive case detection (RACD), is practised for surveillance and response. However, other approaches could be more effective for reducing transmission. We aimed to evaluate the effectiveness of reactive focal mass drug administration (rfMDA) and reactive focal vector control (RAVC) in the low malaria-endemic setting of Zambezi (Namibia). Methods We did a cluster-randomised controlled, open-label trial using a two-by-two factorial design of 56 enumeration area clusters in the low malaria-endemic setting of Zambezi (Namibia). We randomly assigned these clusters using restricted randomisation to four groups: RACD only, rfMDA only, RAVC plus RACD, or rfMDA plus RAVC. RACD involved rapid diagnostic testing and treatment with artemether-lumefantrine and single-dose primaquine, rfMDA involved presumptive treatment with artemether-lumefantrine, and RAVC involved indoor residual spraying with pirimiphos-methyl. Interventions were administered within 500 m of index cases. To evaluate the effectiveness of interventions targeting the parasite reservoir in humans (rfMDA vs RACD), in mosquitoes (RAVC vs no RAVC), and in both humans and mosquitoes (rfMDA plus RAVC vs RACD only), an intention-to-treat analysis was done. For each of the three comparisons, the primary outcome was the cumulative incidence of locally acquired malaria cases. This trial is registered with ClinicalTrials.gov , number NCT02610400 . Findings Between Jan 1, 2017, and Dec 31, 2017, 55 enumeration area clusters had 1118 eligible index cases that led to 342 interventions covering 8948 individuals. The cumulative incidence of locally acquired malaria was 30·8 per 1000 person-years (95% CI 12·8–48·7) in the clusters that received rfMDA versus 38·3 per 1000 person-years (23·0–53·6) in the clusters that received RACD; 30·2 per 1000 person-years (15·0–45·5) in the clusters that received RAVC versus 38·9 per 1000 person-years (20·7–57·1) in the clusters that did not receive RAVC; and 25·0 per 1000 person-years (5·2–44·7) in the clusters that received rfMDA plus RAVC versus 41·4 per 1000 person-years (21·5–61·2) in the clusters that received RACD only. After adjusting for imbalances in baseline and implementation factors, the incidence of malaria was lower in clusters receiving rfMDA than in those receiving RACD (adjusted incidence rate ratio 0·52 [95% CI 0·16–0·88], p=0·009), lower in clusters receiving RAVC than in those that did not (0·48 [0·16–0·80], p=0·002), and lower in clusters that received rfMDA plus RAVC than in those receiving RACD only (0·26 [0·10–0·68], p=0·006). No serious adverse events were reported. Interpretation In a low malaria-endemic setting, rfMDA and RAVC, implemented alone and in combination, reduced malaria transmission and should be considered as alternatives to RACD for elimination of malaria. Funding Novartis Foundation, Bill & Melinda Gates Foundation, and Horchow Family Fund.

Background Subpatent malaria infections, or low-density infections below the detection threshold of microscopy or standard rapid diagnostic testing (RDT), can perpetuate persistent transmission and, therefore, may be a barrier for countries like Namibia that are pursuing malaria elimination. This potential burden in Namibia has not been well characterized. Methods Using a two-stage cluster sampling, cross-sectional design, subjects of all age were enrolled during the end of the 2015 malaria transmission season in Zambezi region, located in northeast Namibia. Malaria RDTs were performed with subsequent gold standard testing by loop-mediated isothermal amplification (LAMP) using dried blood spots. Infection prevalence was measured and the diagnostic accuracy of RDT calculated. Relationships between recent fever, demographics, epidemiological factors, and infection were assessed. Results Prevalence of Plasmodium falciparum malaria infection was low: 0.8% (16/1919) by RDT and 2.2% (43/1919) by LAMP. All but one LAMP-positive infection was RDT-negative. Using LAMP as gold standard, the sensitivity and specificity of RDT were 2.3% and 99.2%, respectively. Compared to LAMP-negative infections, a higher portion LAMP-positive infections were associated with fever (45.2% vs. 30.4%, p = 0.04), though 55% of infections were not associated with fever. Agricultural occupations and cattle herding were significantly associated with LAMP-detectable infection (Adjusted ORs 5.02, 95% CI 1.77–14.23, and 11.82, 95% CI 1.06–131.81, respectively), while gender, travel, bed net use, and indoor residual spray coverage were not. Conclusions This study presents results from the first large-scale malaria cross-sectional survey from Namibia using molecular testing to characterize subpatent infections. Findings suggest that fever history and standard RDTs are not useful to address this burden. Achievement of malaria elimination may require active case detection using more sensitive point-of-care diagnostics or presumptive treatment and targeted to high-risk groups. Electronic supplementary material The online version of this article (10.1186/s12936-018-2626-5) contains supplementary material, which is available to authorized users.

The growing prevalence of deadly microbes with resistance to previously life-saving drug therapies is a dire threat to human health. Detection of low abundance pathogen sequences remains a challenge for metagenomic Next Generation Sequencing (NGS). We introduce FLASH (Finding Low Abundance Sequences by Hybridization), a next-generation CRISPR/Cas9 diagnostic method that takes advantage of the efficiency, specificity and flexibility of Cas9 to enrich for a programmed set of sequences. FLASH-NGS achieves up to 5 orders of magnitude of enrichment and sub-attomolar gene detection with minimal background. We provide an open-source software tool (FLASHit) for guide RNA design. Here we applied it to detection of antimicrobial resistance genes in respiratory fluid and dried blood spots, but FLASH-NGS is applicable to all areas that rely on multiplex PCR.

Local and cross-border importation remain major challenges to malaria elimination and are difficult to measure using traditional surveillance data. To address this challenge, we systematically collected parasite genetic data and travel history from thousands of malaria cases across northeastern Namibia and estimated human mobility from mobile phone data. We observed strong fine-scale spatial structure in local parasite populations, providing positive evidence that the majority of cases were due to local transmission. This result was largely consistent with estimates from mobile phone and travel history data. However, genetic data identified more detailed and extensive evidence of parasite connectivity over hundreds of kilometers than the other data, within Namibia and across the Angolan and Zambian borders. Our results provide a framework for incorporating genetic data into malaria surveillance and provide evidence that both strengthening of local interventions and regional coordination are likely necessary to eliminate malaria in this region of Southern Africa., eLife digest : The number of malaria cases has dropped in some Southern Africa countries, but others still remain seriously affected. When people travel within and between countries, they can bring the parasites that cause the disease to different areas. This can fuel local transmission or even lead to outbreaks in a malaria-free area. When new malaria patients are diagnosed, they are often asked to report their recent travel history, so that the origin of their infection can be tracked. In theory, this would help to spot regions where the disease is imported from, and design targeted interventions. However, it is difficult to know exactly where the parasites come from based on self-disclosed travel history. At best, this history can provide information about that persons infection but nothing further in the past; at worst this history can be completely incorrect. Parasite DNA, on the other hand, has the potential to bring with it an indelible record of the past. To address the problem of determining where malaria infections came from, Tessema, Wesolowski et al. focused on Northern Namibia, a region where malaria persists despite being practically absent from the rest of the country. Patients movements were assessed using mobile phone call records as well as self-reported travel history In addition, samples a single drop of blood were taken so that the genetic information of the parasites could be examined. Combining genetic data with travel history and phone records, Tessema, Wesolowski et al. found that, in Northern Namibia, most people had gotten infected by malaria locally. However, the genetic analyses also revealed that certain infections came from places across the Angolan and Zambian borders, information that was much more difficult to obtain using self-report or mobile phone data. A new, separate study by Chang et al. also supports these results, showing that, in Bangladesh, combining genetic data with travel history and mobile phone records helps to track how malaria spreads. Overall, the work by Tessema, Wesolowski et al. indicate that, in Northern Namibia, it will be necessary to strengthen local interventions to eliminate malaria. However, different countries in the region may also need to coordinate to decrease malaria nearby and reduce the number of cases coming into the country. While genetic data can help to monitor how new malaria cases are imported, this knowledge will be most valuable if it is routinely collected across countries. New tools will also be required to translate genetic data into information that can easily be used for control and elimination programs.

Ethnopharmacological relevance Acanthosicyos naudininus, Gomphocarpus fruticosus, and Cryptolepis decidua are, according to the knowledge of traditional healers, used in Namibia to treat inflammatory disorders such as pain, fever and skin rashes. Aim of the study: The present study was conducted to evaluate the immunomodulatory effects and the possible underlying mechanisms of action of the plant extracts on peripheral blood mononuclear cells (PBMCs) such as T-lymphocytes. Materials and methods Methanolic and EtOAc extracts of A. naudinianus, G. fruticosus and C. decidua were analysed for their immunomodulatory potential. PBMCs were isolated from the blood of healthy donors and incubated with the plant extracts at concentrations 100, 30, 10, 3, 1 and 0.3 μg/mL. Effects on proliferation and viability of activated human lymphocytes were assessed in comparison to ciclosporin A by flow cytometry using carboxyfluorescein succinimidyl ester (CFSE) and WST-1 assay. Flow cytometry by annexin V/propidium iodide (PI) staining was performed to investigate the necrotic/apoptotic effect of the plant extracts on mitogen-activated human lymphocytes. In addition, analysis of the influence of plant extracts on the regulatory mechanisms of T-lymphocytes was performed using activation marker and cytokine production assays. An HPLC-PDA-ELSD-ESIMS profile was recorded for each of the extracts. Results T-lymphocyte proliferation was inhibited in a dose-dependent manner by the extracts of A. naudinianus, G. fruticosus, and C. decidua in concentrations not causing apoptosis or necrosis. This effect was mediated by inhibition of lymphocyte activation, specifically the suppression of CD25 and CD69 surface receptor expression. Moreover, the extracts suppressed effector functions, as indicated by reduced production of IFN-γ and IL-2. Based on the HPLC profile, possible responsible compound classes could be identified for the extracts of A. naudinianus (cucurbitacins) and C. decidua (indole alkaloids), but not for G. fruticosus. Conclusions The data show that the extracts of A. naudinianus, G. fruticosus and C. decidua have in vitro immunomodulatory activity and they interfere with the function of immunocompetent cells, suggesting an anti-inflammatory mode-of-action. The present chemical determination and pattern recognition results explain the therapeutic potency. However, further studies to investigate the therapeutic potential of the plants in inflammatory disorders should be done.

Background: In low-endemic malaria settings, screening and treatment near index cases (reactive case detection, RACD) is practiced for surveillance and response; however, other approaches may be more effective. Methods: We conducted a cluster-randomised controlled two-by-two factorial design trial to evaluate the impact of reactive focal mass drug administration, rfMDA, and reactive focal vector control, RAVC, in the low-endemic setting of Zambezi, Namibia. Fifty-six clusters were randomised to: RACD or rfMDA, and RAVC or no RAVC (RACD: rapid diagnostic testing and treatment with artemether-lumefantrine (AL); rfMDA: presumptive treatment with AL; RAVC: indoor residual spraying using pirimiphos-methyl), with interventions administered within 500 meters of index cases. To evaluate the effectiveness of interventions targeting the parasite reservoir in humans (rfMDA vs RACD), in mosquitos (RAVC vs no RAVC), and in both humans and mosquitoes (rfMDA+RAVC vs RACD only), a modified intention-to-treat analysis was used to compare cumulative incidence of locally acquired malaria cases and cross-sectional prevalence of infection with parasites. Trial registration: ClinicalTrials.gov NCT02610400. Findings: From Jan-Nov 2017, 55 clusters had index cases triggering 342 interventions that covered 8 948 individuals. Incidence per 1 000 person-years for rfMDA, RAVC, and rfMDA+RAVC clusters vs control was: 30·8 vs 38·3 (adjusted incidence rate ratio (aIRR) 0·54 [95% CI 0·14-0·94, p=0·03]), 30·2 vs 38·9 (aIRR 0·51 [0·12-0·90, p=0·01]), and 25·0 vs 41·4 (aIRR 0·28 [0·10-0·84, p=0·02]), respectively. Compared to control, prevalence of infection (%) for rfMDA, RAVC, and rfMDA+RAVC vs control was 3·2 vs 3·8 (adjusted prevalence ratio (aPR) 0·58 [95% CI 0·18-0·98, p=0·04]), 2·9 vs 4·1 (aPR 0·34 [0·11-0·57, p

Background As malaria transmission decreases, the proportion of infections that are asymptomatic at any given time increases. This poses a challenge for diagnosis as routinely used rapid diagnostic tests (RDTs) miss asymptomatic malaria cases with low parasite densities due to poor sensitivity. Yet, asymptomatic infections can contribute to onward transmission of malaria and therefore act as infectious reservoirs and perpetuate malaria transmission. This study compared the performance of RDTs to loop-mediated isothermal amplification (LAMP) in the diagnosis of malaria during reactive active case detection surveillance. Methods All reported malaria cases in the Engela Health District of Namibia were traced back to their place of residence and persons living within the four closest neighbouring houses to the index case (neighbourhood) were tested for malaria infection with RDTs and dried blood spots (DBS) were collected. LAMP and nested PCR (nPCR) were carried out on all RDTs and DBS. The same procedure was followed in randomly selected control neighbourhoods. Results Some 3151 individuals were tested by RDT, LAMP and nPCR. Sensitivity of RDTs and LAMP were 9.30 and 95.50%, respectively, and specificities were 99.27 and 99.92%, respectively, compared to nPCR. LAMP carried out on collected RDTs showed a sensitivity and specificity of 95.35 and 99.85% compared to nPCR carried out on DBS. There were 2 RDT samples that were negative by LAMP but the corresponding DBS samples were positive by PCR. Conclusion The study showed that LAMP had the equivalent performance as nPCR for the identification of Plasmodium falciparum infection. Given its relative simplicity to implement over more complex and time-consuming methods, such as PCR, LAMP is particularly useful in elimination settings where high sensitivity and ease of operation are important.

Malaria cases sometimes go undetected using RDTs due to their inaccurate use, poor storage conditions and failure to detect low parasitaemia (

Setting: Kavango, a 'moderate' transmission risk region located in north-eastern Namibia, borders Angola, a country with higher malaria transmission levels. Objective: To determine 1) the trends in malaria incidence between 2010 and 2014 in Kavango, 2) the socio-demographic and clinical characteristics of confirmed cases in 2014, and 3) associated risk factors of cases classified as imported. Design: This was a retrospective study of malaria case investigation forms conducted in all 52 public health facilities in 2014. Incidence was derived from aggregate routine surveillance data from the Health Information System (HIS). Results: During the 5-year study, incidence fell from 53.6 to 3.6 cases per 1000 population, then increased again to 47.3/1000. Fifty-five per cent of cases were males, and 49% were aged between 5 and 17 years. Of the 2014 cases, 23% were imported, and were associated with higher odds of severe malaria (adjusted odds ratio [aOR] 1.8; 95%CI 1.01-3.29), not having long-lasting insecticide treated nets (aOR 2.1, 95%CI, 1.3-3.4) and not receiving insecticide residual spraying (aOR 3.2, 95%CI, 2.1-5.1). Conclusion: Sporadic outbreaks in the 5-year period posed a threat to malaria elimination. Better targeting of vector control interventions, strong cross-border collaboration and robust health promotion will be key to achieving malaria elimination.

This study aimed to determine the suitability of ethnomedicinal plants as a suitable option for palliative care of cancer in Namibia. To achieve this, key informant interviews were conducted in central and northern parts of Namibia on the use of ethnomedicinal plant products for palliation of cancer. Information from surveys on the medicinal use of plants in Oshikoto and Zambezi regions of Namibia for ailments such as tumors were used to select plants for phytochemical analysis. Plants were collected and extracts were prepared for analysis for phytochemical detection using thin layer chromatography, anti-protease, antioxidant and phytochemical quantification of Colophospermum mopane and Shinziophyton rautanenii plants. Findings from key informant interviews revealed pain management for cancer patients was the primary form of disease management at health care facilities in contrast to an established holistic palliative care system. As a result, patients looked towards alternative treatment from ethnomedicinal plant sources in their bid to palliate cancer and seek hope. Phytochemical analysis of indigenous plants collected, revealed the presence of class compounds such as flavonoids, alkaloids, triterpenes, coumarins and anthraquinones as well as biological activities such as anti-protease, antioxidant properties. In conclusion, phytochemical properties of the six plants were consistent with their ethnomedicinal use, making them a suitable option for treatment of cancer in resource poor settings such as Namibia. Further studies are required to evaluate safety and mode of action. Key words: Palliative care, Namibia, medicinal plants, anti-cancer.

Cancer is a major health problem, not only in developed countries, but also in developing countries where the number of cancer-related ailments is growing. Chemotherapy is the most commonly used treatment option but side effects associated with its use necessitates the search for alternatives. Over 80% of the population in developing countries relies on ethnomedicinal plants for primary healthcare including cancer. There are concerns about the safety and efficacy of such ethnomedicines but unfortunately, the prerequisite laboratory set up for such evaluation is usually lacking. An inexpensive, sensitive, field oriented assay would greatly facilitate and improve research into alternative anticancer plant based medicinal therapies. This study proposes to evaluate the suitability of Dugesia dorotocephala as an alternative laboratory method for antiproliferative properties of indigenous plant extracts. Brown planaria, D. dorotocephala maintained under laboratory settings were divided into three groups, each containing a minimum of three planaria. Each planaria was dissected into two using a sterile scalpel. The tail section was transferred into a 24 well plate, after measuring its length in mm. Root and bark extracts of Colophospermum mopane and Schinziophyton rautanenii were prepared at concentrations (5 and 20 µg/ml) and incubated with dissected planaria for 8 days, fresh extracts were replaced every two days and the planaria was observed for its length in addition to the development of eye spots. Planaria regeneration was observed in control wells receiving no treatment, however, a growth promoting effect was exhibited by S. rautanenii root extract in a time and concentration dependant manner at 5 µg/ml. An anti-proliferative effect was observed for S. rautanenii bark extracts and this was observed at both concentrations, with the higher extract of 20 µg/ml exhibiting more growth antiproliferative activity. The extract of C. mopane root had a cytotoxic effect at concentration 20 µg/ml, causing planaria death. The use of Planaria represents an inexpensive, quantifiable, field oriented method to evaluate the effect of indigenous plant extracts in the absence of cell culture. This method is capable of distinguishing between different treatments, extract concentrations as well as time points. Key words: Dugesia dorotocephala, plant extracts, anti-proliferative, alternative method.

Setting: A comparison of routine Namibia National Malaria Programme data (reported) vs. household survey data (administrative) on indoor residual spraying (IRS) in western Zambezi region, Namibia, for the 2014-2015 malaria season. Objectives: To determine 1) IRS coverage (administrative and reported), 2) its effect on malaria incidence, and 3) reasons for non-uptake of IRS in western Zambezi region, Namibia, for the 2014-2015 malaria season. Design: This was a descriptive study. Results: IRS coverage in western Zambezi region was low, ranging from 42.3% to 52.2% for administrative coverage vs. 45.9-66.7% for reported coverage. There was no significant correlation between IRS coverage and malaria incidence for this region (r = -0.45, P = 0.22). The main reasons for households not being sprayed were that residents were not at home during spraying times or that spray operators did not visit the households. Conclusions: IRS coverage in western Zambezi region, Namibia, was low during the 2014-2015 malaria season because of poor community engagement and awareness of times for spray operations within communities. Higher IRS coverage could be achieved through improved community engagement. Better targeting of the highest risk areas by the use of malaria surveillance will be required to mitigate malaria transmission. Contexte : Une comparaison des donnees de routine du programme national de lutte centre le paludisme de Namibie (rapportees) et des donnees d'enquete dans les foyers (administratives) relatives a la pulverisation d'insecticide a effet remanent (IRS) dans la region ouest du Zambeze, en Namibie, pour la saison 2014–2015 du paludisme.Objectifs : Determiner 1) la couverture de l'IRS (administrative et rapportee), 2) son effet sur l'incidence du paludisme, et 3) les raisons de la non couverture de l'IRS dans la region ouest du Zambeze, Namibie, pendant la saison 2014–2015 du paludisme.Schema : Une etude descriptive.Resultats : La couverture de l'IRS dans la region ouest du Zambeze a ete faible, allant de 42,3% a 52,2% pour la couverture administrative contre 45,9% a 66,7% pour la couverture rapportee. Il n'y a pas eu de correlation significative entre couverture de l'IRS et incidence du paludisme dans cette region (r = −0,45 ; P = 0,22). Les raisons majeures pour lesquelles les foyers n'ont pas beneficie de pulverisations ont ete l'absence des residents a leur domicile lors de la pulverisation ou, inversement, la non-venue des operateurs de pulverisation dans les foyers.Conclusions : La couverture de l'IRS dans la region ouest du Zambeze, Namibie, a ete faible pendant la saison 2014–2015 du paludisme en raison de l'engagement mediocre de la communaute et de la meconnaissance des dates d'operations de pulverisation dans les communautes. Une couverture plus elevee de l'IRS pourrait etre obtenue avec une meilleur engagement de la communaute. Un meilleur ciblage des zones a risque les plus eleves en utilisant la surveillance du paludisme sera requis pour attenuer la transmission du paludisme. Marco de referencia: Una comparacion de los datos corrientes del Programa Nacional contra el Paludismo de Namibia (notificados), con los datos de una encuesta domiciliaria (administrativos) sobre la fumigacion de interiores con insecticidas de efecto residual (IRS) en la region occidental de Zambezi en Namibia, durante la temporada de paludismo del 2014–2015.Objetivos: Determinar 1) la cobertura de la IRS (administrativa y notificada), 2) su efecto sobre la incidencia de paludismo, y 3) las razones de la falta de IRS en la region occidental de Zambezi, en Namibia, durante la temporada de paludismo del 2014–2015.Metodo: Un estudio descriptivo.Resultados: La cobertura de la IRS en la region occidental de Zambezi fue baja, del 42,3% al 52,2% segun la cobertura administrativa, en comparacion con el 45,9% al 66,7% segun la cobertura notificada. paludismo en la region (r = −0,45; P = 0,22). Las principales razones por las cuales no se fumigaron los domicilios fueron que los residentes no se encontraban presentes en el momento de la fumigacion o que los operadores de fumigacion no visitaron los hogares.Conclusiones: La cobertura de la fumigacion de interiores con insecticidas de efecto residual en la region occidental de Zambezi, en Namibia, fue baja durante la temporada de paludismo del 2014–2015 por falta de participacion comunitaria y de conocimiento de los horarios de fumigacion en las comunidades. La cobertura se puede ampliar si se fomenta el compromiso comunitario y es necesario dirigir mejor las campanas a las zonas de mayor riesgo, segun lo indiquen los datos de la vigilancia del paludismo, con el proposito de disminuir la transmision de la enfermedad.

Background: Plants have consistently proven to be a reliable and yet not fully explored source of medicines. In light of this, there is a constant demand for new treatment regimens for cancer. Namibia has a rich diversity of plant species of over 4300 with 17 % of them being endemic to Namibia. Plants growing in Namibia’s diverse climatic zones produce many secondary metabolites as part of adaptation to their environment. This article focused on the screening of such phytochemicals and their cytotoxic and anticancer properties in vitro. Two Namibian plants Diospyros chamaethamnus and Guibourtia coleosperma were randomly selected for this purpose. Materials and Methods: The plants were screened for the presence of coumarins, alkaloids, flavonoids, anthraquinones, steroids and terpenoids using thin layer chromatography. Anticancer screening was performed on a panel of three cancer cell lines, while cytotoxicity was determined using a human fibroblast cell line, both using the SRB method. Results: Alkaloids, anthraquinones, flavonoids and steroids were detected in both organic and aqueous extracts of the two plants. The organic plant extracts had a greater anti-proliferative effect on the cancer cell lines than the aqueous extracts; the D. chamaethamnus organic root extract was the most potent with an IC50 of 16.08, 29.12 and 24.67 μg/mL against TK10, UACC62 and MCF7 cells, respectively. Furthermore, cytotoxicity analysis revealed the non-toxic nature of the extracts, except for the organic root extract of D. chamaethamnus that showed significant cytotoxicity (IC50 13.03 μg/mL). Conclusion: D. chamaethamnus is a potential candidate for the development of a plant based cancer treatment. The study showed the value of random screening in drug discovery from plants for pharmacological activity that is unrelated to their ethnomedicinal uses.

Background: Plants have consistently proven to be a reliable and yet not fully explored source of medicines. In light of this, there is a constant demand for new treatment regimens for cancer. Namibia has a rich diversity of plant species of over 4300 with 17 % of them being endemic to Namibia. Plants growing in Namibia’s diverse climatic zones produce many secondary metabolites as part of adaptation to their environment. This article focused on the screening of such phytochemicals and their cytotoxic and anticancer properties in vitro. Two Namibian plants Diospyros chamaethamnus and Guibourtia coleosperma were randomly selected for this purpose. Materials and Methods: The plants were screened for the presence of coumarins, alkaloids, flavonoids, anthraquinones, steroids and terpenoids using thin layer chromatography. Anticancer screening was performed on a panel of three cancer cell lines, while cytotoxicity was determined using a human fibroblast cell line, both using the SRB method. Results: Alkaloids, anthraquinones, flavonoids and steroids were detected in both organic and aqueous extracts of the two plants. The organic plant extracts had a greater anti-proliferative effect on the cancer cell lines than the aqueous extracts; the D. chamaethamnus organic root extract was the most potent with an IC50 of 16.08, 29.12 and 24.67 µg/mL against TK10, UACC62 and MCF7 cells, respectively. Furthermore, cytotoxicity analysis revealed the non-toxic nature of the extracts, except for the organic root extract of D. chamaethamnus that showed significant cytotoxicity (IC50 13.03 µg/mL). Conclusion: D. chamaethamnus is a potential candidate for the development of a plant based cancer treatment. The study showed the value of random screening in drug discovery from plants for pharmacological activity that is unrelated to their ethnomedicinal uses.

This paper describes the evolution of indigenous knowledge systems documentation at the Multidisciplinary Research Centre, University of Namibia. As awareness of the value of indigenous knowledge systems has increased it has become apparent that it is threatened with extinction and there is a need to document it. Documentation of indigenous knowledge systems is important to preserve indigenous knowledge so it continues to provide local solutions or alternatives to Western knowhow and instill pride in rural communities about their indigenous knowledge systems. There is no clearly defined approach to document indigenous knowledge systems accurately and in its entirety; such a process has to develop, evolve and improve over time. Documentation at the Multidisciplinary Research Centre at the University of Namibia has gone through several phases of refinement with lessons being learnt and efforts being made to improve the process of documentation to capture indigenous knowledge as accurately as possible. The a...

Some formulations of liposomal doxorubicin with intermediate rates of drug release have shown increased levels of toxicity in mice. Because antibody-mediated targeting of liposomal drugs influences the pharmacokinetics, mechanism of uptake, and selectivity of the associated drugs, we hypothesized that anti-CD19-mediated targeting of liposomal doxorubicin might moderate the toxicity of the problem formulations. Phosphatidylcholine/cholesterol liposomal formulations of doxorubicin having faster, intermediate, and slower drug release rates were prepared by altering the fatty acyl chain length or degree of saturation of the phosphatidylcholine component. Pharmacokinetic and biodistribution studies and in vivo drug release rates were determined in mice using liposomes dual labeled with [3H]cholesteryl hexadecylether and [14C]doxorubicin. Therapeutic studies were done in xenograft models of human B lymphoma (Namalwa cells). The rate of clearance of the liposomal lipid was similar for all formulations (average t1/2, 18 hours), but the rate of clearance of doxorubicin was dependent on the release rate of the formulation (t1/2, 2-315 hours). Liposomes with the slowest drug release rates showed no toxicity and exhibited therapeutic activity that was superior to the other formulations when targeted with anti-CD19; liposomes with the most rapid drug release rates also showed no toxicity but showed little therapeutic effect even when targeted. Liposomes with intermediate drug release rates exhibited varying degrees of toxicity. The toxicities could be reduced and even overcome by targeting with anti-CD19 antibodies. For these formulations, therapeutic effects were intermediate between those found for liposomes with the fastest and slowest drug release rates.

A method was developed for identification and quantification of polyphenols in the leaves ofXimenia caffrausing HPLC/UV/MS. Based on analyzing the MS and UV data and in comparison to the authentic standards, a total of 10 polyphenols were identified and quantified, including gallic acid, catechin, quercetin, kaempferol, and their derivatives. The total content of these compounds was found to be approximately 19.45 mg/g in the leaf and the most abundant is quercetin-rutinoside (9.08 mg/g). The total phenolic content as measured by Folin-Ciocalteu assay was 261.87 ± 7.11 mg GAE/g and the total antioxidant capacity as measuredin vitrowas 1.46 ± 0.01 mmol Trolox/g. The antiproliferative effect of the leaf extract was measured by MTS assay with IC50value of 239.0 ± 44.5 μg/mL. Cell-based assays show that the leaf extract inhibits the mRNA expression of proinflammatory genes (IL-6, iNOS, and TNF-α) by using RT-qPCR, implying its anti-inflammatory effects. It was further demonstrated that the underlying therapeutic mechanism involves the suppression of NF-κB, a shared pathway between cell death and inflammation.

Patients with advanced or metastatic melanoma have a very poor prognosis, due to the resistance of melanoma cells to conventional chemotherapy. We previously reported that coated cationic liposomes targeted with a monoclonal antibody against the disialoganglioside GD 2 and containing c-myc antisense oligodeoxynucleotides (αGD 2 -CCL[c-myc-as]) induced partial tumor growth arrest in melanoma xenografts. Here we addressed the role of c-myc-asODN treatment in the susceptibility to doxorubicin (DXR) in human melanoma cells. Cytotoxicity studies revealed that growth of melanoma cells was inhibited to a greater extent by αGD 2 -CCL[c-myc-as] than by the corresponding non-targeted formulations or by free c-myc-as. Targeted c-myc-as sensitized cells to DXR, reducing the IC 50 by approximately 10-fold. Scrambled ODNs had no effect on the IC 50 of DXR. Compared to either treatment alone, combination of targeted c-myc-as and DXR resulted in earlier apoptosis and in cell death after 2 days of treatment. In vivo experiments revealed that liposomal formulations of c-myc-as and DXR, both targeted via GD 2 , led to the most pronounced delay in tumor growth when administered in a sequential manner. As a result, their combination translates into a statistically significant suppression of blood vessel density and an enhanced apoptosis, compared to all treatments given separately. Our data indicate the increasing cell sensitivity to DXR by c-myc-asODNs as a promising basis for developing novel anti-tumor strategy against advanced melanoma.

The selective toxicity of anticancer drugs can be improved with the use of antibody-targeted liposomes. We hypothesize that liposomes targeted via antibodies against two or more receptor populations will increase the apparent receptor density on the target cells, resulting in improved therapeutic affects. A fluorescent assay was developed, using the fluorophores Alexa Fluor 350 and 532 to label monoclonal antibodies (mAb), and used to quantitate two different mAb populations coupled to the same liposome surface to within +/-10% of the values obtained with radiolabeled antibody (125I) tracers. The binding and uptake of targeted liposomes by B lymphoma (Namalwa) cells were examined for either individual populations of alphaCD19-targeted or alphaCD20-targeted liposomes, mixed populations (1:1) of alphaCD19-targeted liposomes plus alphaCD20-targeted liposomes, and dual-targeted liposomes, i.e., equal amount of both alphaCD19 and alphaCD20 on the same liposomes. At similar antibody densities, the binding and uptake of the dual-targeted liposomes were greater than that of either individually targeted liposomes alone, and showed additivity. At the same total lipid and antibody densities, 1:1 mixtures of individually targeted liposomes gave similar results to dual-targeted liposomes. Cytotoxicity was also improved, with DXR-loaded dual-targeted liposomes appearing to have higher cytotoxicity than 1:1 mixtures of individually targeted liposomes.