Molecular Detection of Acinetobacter Species in Lice and Keds of Domestic Animals in Oromia Regional State,Ethiopia

This study was conducted to determine the presence of Acinetobacter and Rickettsia species DNA in lice and Melophagus ovinus (sheep ked) of animals from Oromia Regional State in Ethiopia. From September through November 2011, a total of 207 cattle, 85 sheep, 47 dogs and 16 cats were examined for ectoparasites. Results of morphological identification revealed several species of ectoparasites: Linognathus vituli (L. vituli), Bovicola bovis (B. bovis) and Solenopotes capillatus (S. capillatus) on cattle; B. ovis and Melophagus ovinus (M. ovinus) on sheep; and Heterodoxus spiniger (H. spiniger) on dogs. There was a significantly (p≤0.0001) higher prevalence of L. vituli observed in cattle than both S. capillatus and B. bovis. Molecular identification of lice using an 18S rRNA gene analysis confirms the identified lice species by morphological methods. We detected different Acinetobacter species among lice (11.1%) and keds (86.4%) including A. soli in L. vituli of cattle, A. lowffii in M. ovinus of sheep, A. pittii in H. spiniger of dogs, 1 new Acinetobacter spp. in M. ovinus and 2 new Acinetobacter spp. in H. spiniger of dogs using partial rpoB gene sequence analysis. There was a significantly higher prevalence of Acinetobacter spp. in keds than in lice (p≤0.00001). Higher percentage of Acinetobacter spp. DNA was detected in H. spiniger than in both B. ovis and L. vituli (p≤0.00001). Carbapenemase resistance encoding genes for blaOXA-23, blaOXA-24, blaOXA-58, blaNDM-1 and blaOXA-51 were not found in any lice and keds. These findings suggest that synanthropic animals and their ectoparasites might increase the risk of human exposure to zoonotic pathogens and could be a source for Acinetobacter spp. infections in humans. However, additional epidemiological data are required to determine whether ectoparasites of animals can act as environmental reservoirs and play a role in spreading these bacteria to both animal and human hosts.     

An ethnobotanical study of medicinal plants in Wayu Tuka District,East Welega Zone of Oromia Regional State,West Ethiopia

Background

Himalayan forests are the most important source of medicinal plants and with useful species for the local people. Kedarnath Wildlife Sanctuary (KWLS) is situated in the interior part of the Garhwal Himalayan region. The presented study was carried out in Madhmeshwar area of KWLS for the ecological status of medicinal plants and further focused on the ethnomedicinal uses of these plants in the study area.

Methods

Ecological information about ethnomedicinal plants were collected using random quadrats in a random sampling technique along an altitudinal gradient in the KWLS. Information on medicinal properties of plants encountered in the present study was generated by questionnaire survey and was also compared with relevant literature.

Results

A total of 152 medicinally important plant species were reported, in which 103 were found herbs, 32 shrubs and 17 were tree species which represented 123 genera of 61 families. A total of 18 plant species fell into the rare, endangered (critically endangered) and vulnerable status categories.

Conclusion

The present study documented the traditional uses of medicinal plants, their ecological status and importance of these plants in the largest protected area of Garhwal Himalaya. This study can serve as baseline information on medicinal plants and could be helpful to further strengthen the conservation of this important resource.     

Plant biodiversity and ethnobotany of Borana pastoralists in Southern Oromia, Ethiopia

A survey of plant biodiversity and ethnobotanical studies was conducted in southern Ethiopia using an integrated approach of botanical collections, group discussions, interviews and questionnaires. Species richness, growth forms and uses of native wild plants are described. Borana pastoralists distinguished and named 86% of the plant species identified. A total of 327 plant species distributed among 197 genera and 69 families are documented: 40% are trees/shrubs, 30% forbs (non-woody plants other than grasses and sedges), 16% grasses, 10% climbers, 2% sedges and 2% succulents. Based on richness of species and usefulness, the most important families are Poaceae, Fabaceae, Lamiaceae and Asteraceae. Two hundred forty-eight species (76%) are used by Borana pastoralists, out of which 42% have multiple uses. Indigenous knowledge of pastoralists on use and management of their plant resources is a valuable source of information for conservation and sustainable utilization of the plant biodiversity and, hence, conservation based on indigenous knowledge is recommended.     

Inappropriate infant feeding practices of HIV-positive mothers attending PMTCT services in Oromia regional state,Ethiopia: a cross-sectional study

Background

Inappropriate infant feeding affects the probability of mother-to-child transmission of HIV and HIV-free survival of infants. However, in Ethiopia limited evidence exists regarding the infant feeding practice of mothers who are HIV-positive. The aim of this study was to determine the prevalence and predictors of inappropriate infant feeding among HIV-positive mothers attending the prevention of mother-to-child transmission (PMTCT) service in Adama and Bushoftu towns, Oromia, central Ethiopia.

Methods

A cross-sectional study was conducted in ten PMTCT service providing health facilities in the towns; 283 mother-infant pairs were enrolled. Appropriate infant feeding practice was defined as exclusive breastfeeding in the first six months of age. Logistic regression was employed to analyze the data and the outputs are presented using adjusted odds ratio (AOR) with 95% confidence intervals (CI).

Results

One hundred thirty of the infants were aged below six months, 103 between 6 and 11 months and 50 were older than 12 months. The prevalence of inappropriate infant feeding was 14.5% (95% CI 10.6, 18.7). About 6.3% and 8.3% practiced exclusive replacement feeding and mixed feeding respectively, in the first six months. Only 1.8% ever expressed their breast milk to feed their baby and none practiced wet nursing. Among 38 mothers who already discontinued breastfeeding 52.6% did so before 12 months of age. Mothers who were HIV-positive and had received antenatal (AOR?=?0.05: 0.01, 0.30) and postnatal visits (AOR?=?0.18: 0.04, 0.81); received infant feeding counseling (AOR?=?0.18: 0.06, 0.55); and disclosed their HIV status to their partners (AOR?=?0.28: 0.12, 0.63), showed a reduction of practicing inappropriate infant feeding. Mothers having breast problems (AOR?=?4.89: 1.54, 15.60) and infants with mouth ulcers (AOR?=?6.41: 2.07, 19.85) were more likely to practice inappropriate feeding.

Conclusion

Prompt management of breast complaints in mothers and mouth ulcer in infants; and provision of nutrition counseling to HIV-positive mothers, especially during antenatal and postnatal care, may help to improve the infant feeding practices for HIV exposed infants.

     

Interrupting malaria transmission: quantifying the impact of interventions in regions of low to moderate transmission

Malaria has been eliminated from over 40 countries with an additional 39 currently planning for, or committed to, elimination. Information on the likely impact of available interventions, and the required time, is urgently needed to help plan resource allocation. Mathematical modelling has been used to investigate the impact of various interventions; the strength of the conclusions is boosted when several models with differing formulation produce similar data. Here we predict by using an individual-based stochastic simulation model of seasonal Plasmodium falciparum transmission that transmission can be interrupted and parasite reintroductions controlled in villages of 1,000 individuals where the entomological inoculation rate is <7 infectious bites per person per year using chemotherapy and bed net strategies. Above this transmission intensity bed nets and symptomatic treatment alone were not sufficient to interrupt transmission and control the importation of malaria for at least 150 days. Our model results suggest that 1) stochastic events impact the likelihood of successfully interrupting transmission with large variability in the times required, 2) the relative reduction in morbidity caused by the interventions were age-group specific, changing over time, and 3) the post-intervention changes in morbidity were larger than the corresponding impact on transmission. These results generally agree with the conclusions from previously published models. However the model also predicted changes in parasite population structure as a result of improved treatment of symptomatic individuals; the survival probability of introduced parasites reduced leading to an increase in the prevalence of sub-patent infections in semi-immune individuals. This novel finding requires further investigation in the field because, if confirmed, such a change would have a negative impact on attempts to eliminate the disease from areas of moderate transmission.     

Incidence of malaria among children living near dams in northern Ethiopia: community based incidence survey

ObjectiveTo assess the impact of construction of microdams on the incidence of malaria in nearby communities in terms of possibly increasing peak incidence and prolonging transmission.DesignFour quarterly cycles of malaria incidence surveys, each taking 30 days, undertaken in eight at risk communities close to dams paired with eight control villages at similar altitudes but beyond flight range of mosquitoes.SettingTigray region in northern Ethiopia at altitudes of 1800 to 2225 m.SubjectsAbout 7000 children under 10 years living in villages within 3 km of microdams and in control villages 8-10 km distant.ResultsOverall incidence of malaria for the villages close to dams was 14.0 episodes/1000 child months at risk compared with 1.9 in the control villages—a sevenfold ratio. Incidence was significantly higher in both communities at altitudes below 1900 m.ConclusionsThere is a need for attention to be given to health issues in the implementation of ecological and environmental development programmes, specifically for appropriate malaria control measures to counteract the increased risks near these dams.

Key messages

• Environmental development may have important effects on the epidemiology of vector borne diseases such as malaria
• This may be particularly important where disease transmission is unstable—for example, in highland areas
• Children in villages near recently constructed microdams in northern Ethiopia had a significantly increased risk of malaria
• It seems that this irrigation development programme is leading to increased malaria transmission across a range of altitudes and seasons
• Intersectoral collaboration is necessary in development projects that may affect communities both positively and negatively

     

Genetic fingerprints of parasites causing severe malaria in a setting of low transmission in Sudan

In this study we intended to examine the extent of genetic diversity of Plasmodium falciparum parasites causing severe malaria (SM). For this purpose, 100 parasite isolates were obtained from patients with SM and uncomplicated malaria, from an area of low and unstable malaria transmission in Sudan. The diversity of infection (DOI) was estimated by relating the number of the different parasite genotypes that were detected to the total number of parasites that were genotyped (parasite population/subpopulation). We used different molecular markers individually (pfcrt-76, pfmr1-86, GLURP size and MSP2 family and size) and as a group to set a multilocus genetic profile for each parasite isolate. The DOI as estimated by MSP2 and GLURP was 0.553 and 0.435, respectively. However, combination of all four molecular markers (multilocus genetic profile) revealed a fingerprint pattern of genetic diversity with a DOI of 0.936, indicating that in SM infection, diversity is the rule and homogeny is the exception. Furthermore, our clinical data suggest that the virulence markers might also be more diverse than expected. In conclusion, the results are unexpected and overturn the assumption that parasites causing SM are a limited subpopulation of virulent parasites or of a clonal nature. However, it was more likely that there was a genetically unique parasite in each infection.     

Fossil Tragelaphini (Artiodactyla: Bovidae) from the Late Pliocene Hadar Formation,Afar Regional State,Ethiopia

The fossil tragelaphins from the late Pliocene of Hadar are described. These are Tragelaphus lockwoodi, new species, and Tragelaphus aff. T. nakuae. Tragelaphus lockwoodi bears long horns that define one complete spiral and that are mediolaterally compressed at the base. In these and other morphological characteristics it approaches the greater kudu, T. strepsiceros, and makes a good ancestral candidate for this living species. The Hadar T. aff. T. nakuae is similar to other specimens of this species from sites >2.8 Ma in East Africa and demonstrates well the major differences between the earlier and later representatives of this taxon. The sizes and morphological variation in the large Hadar T. aff. T. nakuae sample supports the idea that female individuals of this species were horned as is the case today in the elands and the bongo. Tragelaphus lockwoodi is present only in the lower beds of the Hadar Formation, and in small numbers, while T. aff. T. nakuae is recovered in relative abundance from throughout the ca. 3.4-ca. 2.9 Ma sequence.     

Spatial and temporal variation in malaria transmission in a low endemicity area in northern Tanzania

Background

Current detection or screening for malaria infection necessitates drawing blood by fingerprick or venipuncture, which poses risks and limitations for repeated measurement. This study presents PCR detection of Plasmodium falciparum in human urine and saliva samples, and illustrates this potential application in genotyping malaria infections.

Methods

Urine and saliva were obtained from 47 thick film positive and 4 negative individuals one day after collection of blood slides and filter paper blood spots. P. falciparum DNA was extracted from blood, urine and saliva, in separate groups, using the Chelex method or Qiagen DNEasy^® kit (urine and saliva only). Blood, urine and saliva extracts were subjected to PCR in separate batches. Amplicons from the various sample types were examined for MSP2 polymorphisms and restriction fragment patterns on DHFR amino acid codon 59.

Results and discussion

Malaria infections exhibited primarily low-grade parasite densities, with a geometric mean of 775 asexual parasites/μl. Regularly matching polymorphic MSP2 genotypes were found between the corresponding urine, saliva and peripheral blood amplicons of each individual, with different inter-individual polymorphic genotypes. Amplicon yields were significantly dependent on DNA extraction method, parasite density and primer set (p < 0.001). A Qiagen^® kit extraction had more than 2× higher amplicon yield than the Chelex method, for both urine and saliva. Amplicon yields were 1.6 fold higher from saliva than urine. For each unit increase in log parasite density, the probability of amplicon enhanced 1.8 fold. Highest amplicon yields were obtained from the primer set with the shortest PCR product.

Conclusion

P. falciparum infection is detectable by PCR on human urine and saliva samples. Subject to further refinement of extraction technique and amplicon yields, large-scale malaria parasite screening and epidemiological surveys could be possible without the need to collect blood and use of needles or sharps.     

Encroachment of woody plants and its impact on pastoral livestock production in the Borana lowlands, southern Oromia, Ethiopia

Encroachment of woody plants has been among the major threats to the livelihoods of Borana pastoralists and their ecosystem. An approach that integrated vegetation survey and pastoralists’ perception was followed to study the impacts of encroachment of woody plants in the Borana lowlands, Ethiopia. Density of woody species was determined in 192 plots of 500 m². Canopy cover of woody plants was estimated in 123 quadrates of 400 m². Pastoralists’ perception was assessed through group discussions and a semi‐structured questionnaire. Results showed that plant density was 3014 woody plants ha^?1. Cover of woody plants was 52%, indicating an increasing trend from ≤40% cover reported in the early 1990s. It was concluded that the increase of woody plants density and cover has crossed the critical threshold and has entered into the encroached condition. Principal components analysis (PCA) and redundancy analysis (RDA) also showed that woody plants were negatively correlated with herbaceous biomass. Commiphora africana, Acacia melliphera, A. drepanolobium, A. brevispica and Lannea rivae were among the dominant encroachers. RDA revealed that soil nutrients were positively correlated with woody plants density and cover. The pastoralists perceived that encroachment of woody plants had decreased the production of their grazingland. A ban on fire was perceived as the major factor that caused encroachment of woody plants. Re‐utilization of fire and strengthening of traditional rangeland management strategies are recommended.     

Vector bionomics and malaria transmission along the Thailand‐Myanmar border: a baseline entomological survey

Baseline entomological surveys were conducted in four sentinel sites along the Thailand‐Myanmar border to address vector bionomics and malaria transmission in the context of a study on malaria elimination. Adult Anopheles mosquitoes were collected using human‐landing catch and cow‐bait collection in four villages during the rainy season from May‐June, 2013. Mosquitoes were identified to species level by morphological characters and by AS‐PCR. Sporozoite indexes were determined on head/thoraces of primary and secondary malaria vectors using real‐time PCR. A total of 4,301 anopheles belonging to 12 anopheline taxa were identified. Anopheles minimus represented >98% of the Minimus Complex members (n=1,683), whereas the An. maculatus group was composed of two dominant species, An. sawadwongporni and An. maculatus. Overall, 25 Plasmodium‐positive mosquitoes (of 2,323) were found, representing a sporozoite index of 1.1% [95%CI 0.66–1.50]. The transmission intensity as measured by the EIR strongly varied according to the village (ANOVA, F=17.67, df=3, P<0.0001). Our findings highlight the diversity and complexity of the biting pattern of malaria vectors along the Thailand‐Myanmar border that represent a formidable challenge for malaria control and elimination.     

Timing of enteral feeding in cerebral malaria in resource-poor settings: a randomized trial

Background

Early start of enteral feeding is an established treatment strategy in intubated patients in intensive care since it reduces invasive bacterial infections and length of hospital stay. There is equipoise whether early enteral feeding is also beneficial in non-intubated patients with cerebral malaria in resource poor settings. We hypothesized that the risk of aspiration pneumonia might outweigh the potential benefits of earlier recovery and prevention of hypoglycaemia.

Method and Findings

A randomized trial of early (day of admission) versus late (after 60 hours in adults or 36 hours in children) start of enteral feeding was undertaken in patients with cerebral malaria in Chittagong, Bangladesh from May 2008 to August 2009. The primary outcome measures were incidence of aspiration pneumonia, hypoglycaemia and coma recovery time. The trial was terminated after inclusion of 56 patients because of a high incidence of aspiration pneumonia in the early feeding group (9/27 (33%)), compared to the late feeding group (0/29 (0%)), p = 0.001). One patient in the late feeding group, and none in the early group, had hypoglycaemia during admission. There was no significant difference in overall mortality (9/27 (33%) vs 6/29 (21%), p = 0.370), but mortality was 5/9 (56%) in patients with aspiration pneumonia.

Conclusions

In conclusion, early start of enteral feeding is detrimental in non-intubated patients with cerebral malaria in many resource-poor settings. Evidence gathered in resource rich settings is not necessarily transferable to resource-poor settings.

Trial Registration

Controlled-Trials.com ISRCTN57488577     

Congenital malaria with atypical presentation: A case report from low transmission area in India

Drug resistant malaria was a major factor contributing to the failure of a worldwide campaign to eradicate malaria in the last century, and now threatens the large investment being made by the global community in the rollout of effective new drug combinations to replace failed drugs. Four related papers in this issue of Malaria Journal make the case for creating the World Antimalarial Resistance Network (WARN), which will consist of four linked open-access global databases containing clinical, in vitro, molecular and pharmacological data, and networks of reference laboratories that will support these databases and related surveillance activities. WARN will serve as a public resource to guide antimalarial drug treatment and prevention policies and to help confirm and characterize the new emergence of new resistance to antimalarial drugs and to contain its spread.     

Controlling malaria transmission with genetically-engineered, Plasmodium-resistant mosquitoes: milestones in a model system

We are developing transgenic mosquitoes resistant to malaria parasites to test the hypothesis that genetically-engineered mosquitoes can be used to block the transmission of the parasites. We are developing and testing many of the necessary methodologies with the avian malaria parasite, Plasmodium gallinaceum, and its laboratory vector, Aedes aegypti, in anticipation of engaging the technical challenges presented by the malaria parasite, P. falciparum, and its major African vector, Anopheles gambiae. Transformation technology will be used to insert into the mosquito a synthetic gene for resistance to P. gallinaceum. The resistance gene will consist of a promoter of a mosquito gene controlling the expression of an effector protein that interferes with parasite development and/or infectivity. Mosquito genes whose promoter sequences are capable of sex- and tissue-specific expression of exogenous coding sequences have been identified, and stable transformation of the mosquito has been developed. We now are developing the expressed effector portion of the synthetic gene that will interfere with the transmission of the parasites. Mouse monoclonal antibodies that recognize the circumsporozoite protein of P. gallinaceum block sporozoite invasion of mosquito salivary glands, as well as abrogate the infectivity of sporozoites to a vertebrate host, the chicken, Gallus gallus, and block sporozoite invasion and development in susceptible cell lines in vitro. Using the genes encoding these antibodies, we propose to clone and express single-chain antibody constructs (scFv) that will serve as the effector portion of the gene that interferes with transmission of P. gallinaceum sporozoites.     

Scattered trees as modifiers of agricultural landscapes: the role of waddeessa (Cordia africana Lam.) trees in Bako area, Oromia, Ethiopia

Scattered trees in general and scattered waddeessa (Cordia africana Lam.) trees in particular are very common across the agricultural landscapes in Oromia, Ethiopia. A study on this scattered waddeessa trees commonly growing on farmers' agricultural fields was conducted at Bako in western Oromia, Ethiopia with the objective of assessing their role in modifying the soil properties in the agricultural landscape. Soil samples from surface layers (0–10 cm) were taken at three concentric transects (0.5, 2 and 4 m) around the tree and compared with soil samples from the adjacent open areas (15 m distance from the tree), and then analysed following the standard procedures. Results showed that scattered waddeessa trees significantly modified the overall properties of the soil in the agricultural landscape of Bako area. But soil texture was not affected, indicating that it is more related to parent material than the tree influence. Hence, the soil patches observed under these waddeessa trees can be important local nutrient reserves that may influence the rural agricultural landscape. They also play an important role in generating local household income from the sale of products and conserving biodiversity by providing habitats and resources that are otherwise absent or scarce in agricultural landscape.     

School-based participatory health education for malaria control in Ghana: engaging children as health messengers

Background

Infected humans make protective antibody responses to the PfEMP1 adhesion antigens exported by Plasmodium falciparum parasites to the erythrocyte membrane, but little is known about the kinetics of this antibody-receptor binding reaction or how the topology of PfEMP1 on the parasitized erythrocyte membrane influences antibody association with, and dissociation from, its antigenic target.

Methods

A Quartz Crystal Microbalance biosensor was used to measure the association and dissociation kinetics of VAR2CSA PfEMP1 binding to human monoclonal antibodies. Immuno-fluorescence microscopy was used to visualize antibody-mediated adhesion between the surfaces of live infected erythrocytes and atomic force microscopy was used to obtain higher resolution images of the membrane knobs on the infected erythrocyte to estimate knob surface areas and model VAR2CSA packing density on the knob.

Results

Kinetic analysis indicates that antibody dissociation from the VAR2CSA PfEMP1 antigen is extremely slow when there is a high avidity interaction. High avidity binding to PfEMP1 antigens on the surface of P. falciparum-infected erythrocytes in turn requires bivalent cross-linking of epitopes positioned within the distance that can be bridged by antibody. Calculations of the surface area of the knobs and the possible densities of PfEMP1 packing on the knobs indicate that high-avidity cross-linking antibody reactions are constrained by the architecture of the knobs and the large size of PfEMP1 molecules.

Conclusions

High avidity is required to achieve the strongest binding to VAR2CSA PfEMP1, but the structures that display PfEMP1 also tend to inhibit cross-linking between PfEMP1 antigens, by holding many binding epitopes at distances beyond the 15-18 nm sweep radius of an antibody. The large size of PfEMP1 will also constrain intra-knob cross-linking interactions. This analysis indicates that effective vaccines targeting the parasite's vulnerable adhesion receptors should primarily induce strongly adhering, high avidity antibodies whose association rate constant is less important than their dissociation rate constant.     

A rapid genotyping method for the vivax malaria transmission-blocking vaccine candidates, Pvs25 and Pvs28

The antigenic diversity observed in many vaccine candidates is one of the difficulties to design effective malaria vaccine. Since it is prerequisite to survey genetic polymorphism of the vaccine candidate antigens for the vaccine development, it is necessary to establish efficient screening method to detect the genetic polymorphism from a large number of samples. Here, we have established efficient polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) method to detect nucleotide diversity of the malaria transmission-blocking vaccine candidates Pvs25 and Pvs28. We can distinguish all 4 haplotypes of Pvs25 by this method. By introducing BsmI-digestion step for Pvs28, we can distinguish 15/16 haplotypes by single electrophoresis. Since this method requires neither sequencing nor radioisotope labeling, it will be easy to transfer the method into a field based high throughput screening of genetic polymorphism.     

A negative binomial model for sampling mosquitoes in a malaria survey

Sampling models are investigated for counts of mosquitoes from a malaria field survey conducted by the World Health Organization in Nigeria. The data can be described by a negative binomial model for two-way classified counted data, where the cell means are constrained to satisfy row-by-column independence and the parameter k is constant across rows. An algorithm, based on iterative proportional fitting, is devised for finding maximum likelihood estimates. Sampling properties of the estimates and likelihood-ratio statistics for the small sample sizes of the data are investigated by Monte Carlo experiments. The WHO reported an observation that the relative efficiencies of four trapping methods vary over time. Out of eight villages in the survey area, this observation is found to be true in only the one village that is near a swamp.     

Net gain: a new method for preventing malaria deaths

edited by C. Lengeler, J. Cattani and D. de Savigny, IDRC, 1996. $30.00 (189 pages) ISBN 0 88936 792 2.