Visceral leishmaniasis treatment outcome and its determinants in northwest Ethiopia

Survival analysis of adult visceral leishmaniasis patients admitted to Metema Hospital, Metema, Ethiopia: a hospital-based cross-sectional study

BACKGROUND

Visceral leishmaniasis (VL) is a neglected tropical disease that mostly affects the working class and impoverished segments of society, having a significant negative effect on the economic development of the affected nation. While anti-leishmanial medications lower mortality among VL patients, patients may still die or require more time to recover while receiving treatment. In this regard, there are limited studies in Ethiopia. This study aims to determine the time to recovery and its associated predictors among adult VL patients at Metema Hospital, Metema, Ethiopia.

METHODS

A hospital-based cross-sectional study was employed and the data were collected from patient's charts from September 2017 to September 2021. Data were entered and analysed using EpiData version 3.1, Stata version 14.2 and R version 3.4.0 statistical software. Kaplan-Meier survival curves and logrank tests were used to compare the survival time. The Cox proportional hazards model assumption and model fitness were checked and used to identify statistical association predictors in VL patients.

RESULTS

The Cox proportional hazards model was fitted. The overall medium recovery time was 7 d (minimum 4, maximum 14). The variables of nasal bleeding (adjusted hazard ratio [aHR] 0.44 [95% confidence interval {CI} 0.19 to 0.89]), no comorbidity (aHR 2.29 [95% CI 1.27 to 4.11]), relapse of VL (aHR 0.33 [95% CI 0.15 to 0.75]), low parasite load (aHR 2.58 [95% CI 1.48 to 4.51]) and ambulatory (aHR 3.26 [95% CI 2.45 to 6.53]) were significantly associated with time to recovery in VL patients.

CONCLUSIONS

Patients with comorbidities, nasal bleeding, relapse of VL, bedridden and high parasite load should be treated and monitored carefully to recover quickly from their illness.

Fever of unknown origin and splenomegaly: a case report of visceral leishmaniasis diagnosed by metagenomic next-generation sequencing

Visceral leishmaniasis (VL) is a parasitic disease caused by Leishmania spp., which is transmitted by sandflies. As China is not the main epidemic area and VL has complex and atypical clinical manifestations, it is easily misdiagnosed or even missed in clinical practice. Without prompt and efficient treatment, the mortality rate of VL is extremely high; therefore early diagnosis of VL is crucial. Herein we describe a case of fever and splenomegaly of unknown origin, which was finally diagnosed as VL by metagenomic next-generation sequencing.

Hematological and Clinical Features Associated with Initial Poor Treatment Outcomes in Visceral Leishmaniasis Patients with and without HIV Coinfection in Gondar, Northwest Ethiopia

Ethiopia is among the countries with a high leishmaniasis burden. In this retrospective review, we aimed to determine hematological and clinical features associated with initial poor treatment outcomes of visceral leishmaniasis (VL) patients. The majority of VL cases in this study had leucopenia (94.3%), thrombocytopenia (87.1%), and anemia (85.9%). HIV coinfection was present in 7.0% (n = 23) of VL cases. At the center, VL patients without HIV coinfection were treated with sodium stibogluconate and paromomycin combination, whereas HIV coinfected cases were treated with AmBisome and miltefosine combination therapy. End-of-treatment cure rates among HIV-positive and HIV-negative visceral leishmaniasis cases, respectively, were 52.2% and 96.9%. Case fatality rates were 34.8% and 2.7% in HIV-positive and HIV-negative cases, respectively. Overall, non-survivors in this study were more likely to have HIV (55.0% vs. 4.1%, p < 0.001), sepsis (15.0% vs. 1.4%, p = 0.019), and dyspnea (40.0% vs. 2.7%, p < 0.001) at admission. In this regard, particular attention to the management of superimposed disease conditions at admission, including sepsis, HIV, and dyspnea, is needed to improve VL patients’ treatment outcomes. The inadequacy of the current treatments, i.e., AmBisome and miltefosine combination therapy, for HIV coinfected visceral leishmaniasis patients requires further attention as it calls for new treatment modalities.

Bioprospecting marine actinomycetes for antileishmanial drugs: current perspectives and future prospects

Revived analysis interests in natural products in the hope of discovering new and novel antileishmanial drug leads have been driven partially by the increasing incidence of drug resistance. However, the search for novel chemotherapeutics to combat drug resistance had previously concentrated on the terrestrial environment. As a result, the marine environment was often overlooked. For example, actinomycetes are an immensely important group of bacteria for antibiotic production, producing two-thirds of the known antibiotics. However, these bacteria have been isolated primarily from terrestrial sources. Consequently, there have been revived efforts to discover new compounds from uncharted or uncommon environments like the marine ecosystem. Isolation, purification and structure elucidation of target compounds from complex metabolic extract are major challenges in natural products chemistry. As a result, marine-derived natural products from actinomycetes that have antileishmanial bioactivity potentials have been understudied. This review highlights metagenomic and bioassay approaches which could help streamline the drug discovery process thereby greatly reducing time and cost of dereplication to identify suitable antileishmanial drug candidates.

Efficacy and safety of a combined treatment of sodium stibogluconate at 20mg/kg/day with upper maximum daily dose limit of 850mg and Paromomycin 15mg/kg/day in HIV negative visceral leishmaniasis patients. A retrospective study, northwest Ethiopia

BACKGROUND

Visceral leishmaniasis (VL) is one of the most neglected tropical infectious diseases. It is fatal if left untreated. The objective of this study was to assess the efficacy and safety of 17-day injections of combined regimen of sodium stibogluconate and paromomycin (SSG/PM) in HIV-negative VL patients.

METHODS

A retrospective analysis of medical records of VL patients treated in the University of Gondar Hospital during period 2012-2019 was carried out.

RESULTS

A total of 2836 patients were treated for VL from 2012 to 2019. Of these 1233 were treated with SSG-PM, and 1000 of them were included in the study. Initial cure was achieved in 922 (92.2%) patients. The frequency of treatment failure, treatment interruptions, default and deaths respectively were 30 (3%), 20 (2%), 13 (1.3%) and 15 (1.5%). Among 280 patients who completed 6-month follow up, the final cure was 93.9% (263/280), 4 (1.4%) relapsed and 13 (4.6%) developed post-kala-azar dermal leishmaniasis (PKDL). The most common adverse events (AEs) were raised liver transaminases (35.1%; 351 patients), injection site pain (29.1%, 291 patients) and raised serum alpha-amylase (29.1%, 291 patients). Factors associated with poor treatment outcomes were sepsis, pneumonia, and adverse events.

CONCLUSION

A combination of SSG at 20mg/kg with upper daily maximum dose of 850mg and PM was effective for achieving initial cure at end of treatment and safe for treatment of HIV negative VL patients in northwestern Ethiopia. Our data are consistent with previous reports and confirms effectiveness of SSG/PM treatment regimen in the Eastern African countries. Efficacy at 6-months (93.9%) was estimated on data derived from patients who completed follow up and needs to be interrogated by future studies.

Inequalities of visceral leishmaniasis case-fatality in Brazil: A multilevel modeling considering space, time, individual and contextual factors

Background

In Brazil, case-fatality from visceral leishmaniasis (VL) is high and characterized by wide differences between the various political-economic units, the federated units (FUs). This study was designed to investigate the association between factors at the both FU and individual levels with the risk of dying from VL, after analysing the temporal trend and the spatial dependency for VL case-fatality.

Methodology

The analysis was based on individual and aggregated data of the Reportable Disease Information System-SINAN (Brazilian Ministry of Health). The temporal and spatial distributions of the VL case-fatality between 2007 and 2017 (27 FUs as unit of analysis) were considered together with the individual characteristics and many other variables at the FU level (socioeconomic, demographic, access to health and epidemiological indicators) in a mixed effects models or multilevel modeling, assuming a binomial outcome distribution (death from VL).

Findings

A linear increasing temporal tendency (4%/year) for VL case-fatality was observed between 2007 and 2017. There was no similarity between the case-fatality rates of neighboring FUs (non-significant spatial term), although these rates were heterogeneous in this spatial scale of analysis. In addition to the known individual risk factors age, female gender, disease’s severity, bacterial co-infection and disease duration, low level schooling and unavailability of emergency beds and health professionals (the last two only in univariate analysis) were identified as possibly related to VL death risk. Lower VL incidence was also associated to VL case-fatality, suggesting that unfamiliarity with the disease may delay appropriate medical management: VL patients with fatal outcome were notified and had VL treatment started 6 and 3 days later, respectively, in relation to VL cured patients. Access to garbage collection, marker of social and economic development, seems to be protective against the risk of dying from VL. Part of the observed VL case-fatality variability in Brazil could not be explained by the studied variables, suggesting that factors linked to the intra FU environment may be involved.

Conclusions

This study aimed to identify epidemiological conditions and others related to access to the health system possibly linked to VL case-fatality, pointing out new prognostic determinants subject to intervention.

Visceral leishmaniasis (VL) is a potentially fatal disease if not diagnosed and treated promptly. The VL case-fatality in Brazil is the highest rate in the world, reaching an average of 7% and in some regions, more than 15%. In the last years, some improvements in the VL approach have been reached in Brazil, such as the widespread use of rapid diagnostic tests and liposomal amphotericin B for treatment of selected high risk of death cases. Despite these interventions, increase in case-fatality rates were observed. In this study we explored the factors related to the case-fatality from VL using a mixed modeling that encompasses different intervening factors such as time/spatial trends and factors linked to the individual and socio-economic indicators. For the first time, factors unrelated to the patients’ clinical condition emerge as possibly related to VL case-fatality, such as low educational level, unavailability of emergency beds and health professionals, suggesting the harmful influence of conditions of limited access to health services. In addition to these significant effects observed in the spatial scale of analysis, this study points to the influence of contextual factors linked to each geopolitical unit. The determinants of death among VL cases may differ according to the region, which requires specific actions planned locally, including increased access to health system qualified to recognize and properly treat VL.

Infectivity and Drug Susceptibility Profiling of Different Leishmania-Host Cell Combinations

Protozoan parasites of the genus Leishmania are the causative agents of leishmaniasis, a spectrum of a disease that threatens public health worldwide. Although next-generation therapeutics are urgently needed, the early stage of the drug discovery process is hampered by very low hit rates from intracellular Leishmania phenotypic high-throughput screenings. Designing and applying a physiologically relevant in vitro assay is therefore in high demand. In this study, we characterized the infectivity, morphology, and drug susceptibility of different Leishmania and host cell infection combinations. Primary bone marrow-derived macrophage (BMDM) and differentiated human acute monocytic leukemia (THP-1) cells were infected with amastigote or promastigote forms of Leishmania amazonensis and Leishmania donovani. Regardless of host cell types, amastigotes were generally well phagocytosed and showed high infectivity, whereas promastigotes, especially those of L. donovani, had predominantly remained in the extracellular space. In the drug susceptibility test, miltefosine and sodium stibogluconate (SSG) showed varying ranges of activity with 14 and >10-fold differences in susceptibility, depending on the host-parasite pairs, indicating the importance of assay conditions for evaluating antileishmanial activity. Overall, our results suggest that combinations of Leishmania species, infection forms, and host cells must be carefully optimized to evaluate the activity of potential therapeutic compounds against Leishmania.

Incidence of Mortality and Its Predictors Among Adult Visceral Leishmaniasis Patients at the University of Gondar Hospital: A Retrospective Cohort Study

Background

Visceral leishmaniasis (VL) is a neglected tropical disease, affecting the poor and productive age group of a country, resulting in a huge impact on its economic development. Even though anti-leishmanial drugs reduce the incidence of mortality among VL patients, there is still death of these patients while on treatment. In this aspect, there are limited studies in Ethiopia; therefore, this study aimed to determine the incidence of mortality and its predictors among adult VL patients at the University of Gondar Hospital.

Methods

Institution-based retrospective cohort study was conducted among 586 adult visceral leishmaniasis patients who were admitted to the University of Gondar Hospital from 2013 to 2018. Data were collected from the patients’ charts and registration books, and analyzed using Stata 14 software. Kaplan–Meier failure curve and Log rank test was used to compare the survival probability of patients with independent variables. A multivariable stratified Cox regression model was used to identify predictors of mortality among VL patients. P≤ 0.05 was employed to declare statistically significant factors. Adjusted hazard ratio (AHR) and 95% confidence interval (95% CI) were estimated for potential risk factors included in the multivariable model.

Results

A total of 586 VL patients were included in the study. The age of patients ranged from 18 to 55 years with a median age of 27 years. The incidence of mortality was 6.6 (95% CI: 5.2–8.4) per 1000 person-days of observation. Independent predictors of mortality were presence of comorbidity (AHR=2.29 (95% CI: 1.27–4.11)), relapse VL (AHR=3.03 (95% CI: 1.25–7.35)), treatment toxicity (AHR=5.87 (95% CI: 3.30–10.44)), nasal bleeding (AHR=2.58 (95% CI: 1.48–4.51)), jaundice (AHR=2.84 (95% CI: 1.57–5.16)) and being bedridden at admission (AHR=3.26 (95% CI: 1.86–5.73)).

Conclusion

The incidence of mortality among VL patients was high. Mortality was higher among VL patients with concomitant disease, relapse VL, treatment toxicity, nasal bleeding, jaundice, and those who were bedridden at admission, which implies that great care should be taken for these risky groups through strict follow-up and treatments.

Prevalence estimates of human immunodeficiency virus (HIV) infection among visceral leishmaniasis infected people in Northwest Ethiopia: a systematic review and meta-analysis

Background

In Ethiopia, by the end of 2018, an estimated 690,000 people are infected with HIV and the annual cases of Visceral Leishmaniasis (VL) is estimated to be between 4000 and 5000 with over 3.2 million people are at risk. Northwest Ethiopia accounts for over 60% cases of VL in the country. Prevalence of HIV infection among VL infected people in Ethiopia has not yet been synthesized. Therefore, we aimed to estimate the pooled prevalence of HIV infection among VL infected people in Northwest Ethiopia with the hope that it would guide the development of a more robust and cost-effective intervention strategies.

Methods

In this systematic review and meta-analysis, we searched six international databases: PubMed, Ovid MEDLINE®, Embase, Scopus, Google Scholar, and ProQuest Dissertations & Theses. We also searched reference lists of included studies and Ethiopian universities electronic thesis and dissertation repositories. The search was performed until June 30,2019. Funnel plot symmetry visualization confirmed by Egger’s regression asymmetry test and Begg rank correlation methods was used to assess publication bias. Pooled prevalence estimate was calculated using Der Simonian and Laird’s random Effects model. We went further to perform univariate meta-regression and subgroup analysis to identify a possible sources of heterogeneity among the studies. STATA software (version 14, Texas, USA) was used for analysis.

Results

From 1286 citations identified by our search, 19 relevant studies with 5355 VL infected individuals were included in this meta-analysis. The pooled prevalence of HIV infection among VL infected individuals in Northwest Ethiopia was 24% (95%CI: 17–30%). The result of sensitivity analysis demonstrated that the pooled prevalence estimate was robust and not one-study dependent. The pooled prevalence estimate of HIV infection among VL infected people in Northwest Ethiopia ranged from 20.88% (95%CI: 15.91–25.86) to 24.86% (95%CI: 18.57–31.14) after a single study was deleted.

Conclusions

The burden of HIV infection in people infected with VL in Northwest Ethiopia is considerably high. Integrating HIV/AIDS surveillance among VL infected people would improve case detection as well as prevention and control of disease spread.

Cutaneous leishmaniasis a neglected tropical disease: community knowledge, attitude and practices in an endemic area, Northwest Ethiopia

Background

Cutaneous leishmaniasis is one of the neglected tropical diseases in the Ethiopian highlands and studies on assessment of knowledge, attitude and practice of the community in endemic areas are scanty. The study aimed to assess the knowledge, attitude towards cutaneous leishmaniasis and treatment seeking practices in people living in the endemic highlands areas in the Northwest, Ethiopia and to provide evidence-based information to guide development of appropriate interventions to reduce the impact of cutaneous leishmaniasis on communities.

Methods

Quantitative cross-sectional study was conducted in cutaneous leishmaniasis endemic districts (woredas) using a semi structured questionnaire. Households were randomly selected according to probability proportional to size of households in each enumeration area. Systematic random sampling of eligible households was based on the number of households recorded during listing of households. Descriptive statistics was used to describe numerical data, organise and summarise the data in a manner that gave meaning to the numerical form. Frequency tables were used to show descriptive analysis and regression analysis was used to determine correlation between variables.

Results

Majority of respondents 321(78.7%) lived in rural areas, age ranged between 18 and 85 years and most were farmers. Illiteracy was high (47.6%) among respondents and majority 358(87.8%) had seen patients with CL. Less than quarter (21.6%) had heard about sand flies and knowledge on the peak transmission period was low (46.3%). About 192 (47.1%) of the respondents indicated disfiguring lesions were the major clinical presentations, less than half 55(27.5%) of urban residents believed CL was treatable compared to 145(72.5%) of rural residents (P < 0.001). Traditional medicines were indicated as best treatment option by 209(51.2%) compared to 114(27.9%) for modern treatment. Major factors influencing treatment options included accessibility to treatment facilities, distance and short duration of treatment. Participants expressed negative experiential attitude and perceived control towards modern treatment because of inaccessibility and distance from where modern treatment is provided.

Conclusion

Priority should be given to primary prevention and appropriate awareness campaigns on lesion recognition. Information on modern treatment should be intensified.

Relationship of Serum Antileishmanial Antibody With Development of Visceral Leishmaniasis, Post-kala-azar Dermal Leishmaniasis and Visceral Leishmaniasis Relapse

Introduction

To sustain the achievement of kala-azar elimination program (KEP), early detection and treatment of the visceral leishmaniasis (VL) cases and associated modalities such as treatment failure (TF), relapse VL (RVL), and Post-kala-azar dermal leishmaniasis (PKDL) is the cornerstone. A predictive biomarker for VL development and related complications could also play a crucial role in curtailing disease incidence and transmission. Investigations to find a biomarker with prospective capabilities are, however, scarce. Using samples and known clinical outcomes generated within two previous longitudinal cohort studies, we aimed to determine if fluctuations in serum anti-rK39 antibody levels could provide such predictive value.

Materials and Methods

Serum samples collected at four different time points (Baseline, 12, 18, and 24 months) from 16 patients who had developed VL within the monitoring period and 15 of their asymptomatic healthy controls counterparts were investigated. To investigate potential prediction of VL related complications, serum samples of 32 PKDL, 10 RVL, 07 TF, and 38 cured VL from a single dose AmBisome trial were analyzed. Of this second panel, all patients were monitored for 5 years and sera were collected at four time points (Baseline then 1, 6, and 12 months after treatment). The level of anti-rK39 antibodies in archived samples was measured by a semi-quantitative ELISA.

Results

The mean antibody level was significantly higher in VL patients compared to their asymptomatic healthy counterparts at each time point. Likewise, we observed a trend toward elevations in antibody levels for PKDL, RVL, TF relative to the reducing levels observed in cured VL. Receiver operating characteristic (ROC) analysis found a promising predictive power of rK39 antibody levels to reveal progression from asymptomatic Leishmania donovani infection stage to VL, defined as 87.5% sensitive and 95% specific. Following treatment, rk39 antibody notably showed 100% sensitivity and 95% specificity in predicting TF.

Conclusion

Our data indicate that the relative quantity of serum anti-rK39 antibody has promise within either a predictive or prognostic algorithm for VL and VL-related modalities. These could enable VL control programs to implement more effective measures to eliminate the disease. Further research is, however, imperative to standardize the rK39 antibody ELISA between sites prior to broader use.

Visceral Leishmaniasis Treatment Outcome and Associated Factors in Northern Ethiopia

Background

Visceral leishmaniasis (VL), one of the most neglected tropical diseases, is placing a huge burden on Ethiopia. Despite the introduction of antileishmanial drugs, treatment outcomes across regions are variable due to drug resistance and other factors. Thus, understanding of VL treatment outcomes and its contributing factors helps decisions on treatment. However, the magnitude and the risk factors of poor treatment outcome are not well studied in our setting. Therefore, our study was designed to assess treatment outcomes and associated factors in patients with VL.

Materials and Methods

A cross-sectional study was conducted in VL patients admitted between June 2016 and April 2018 to Ayder Comprehensive Specialized Hospital, Tigray, Northern Ethiopia. Data was collected through chart review of patient records. Logistic regression analysis was used to identify factors associated with poor treatment outcome.

Results

A total of 148 VL patients were included in the study. The mean age (SD) of the patients was 32.86 (11.9) years; most of them (94.6%) were male patients. The proportion of poor treatment outcome was 12.1%. Multivariable logistic regression analysis showed that long duration of illness (> four weeks) (adjusted odds ratio (AOR): 6.1 [95% confidence interval (CI); 1.3-28.6], p=0.02) and concomitant tuberculosis (TB) infection (AOR 4.6 [95% CI; 1.1-19.1], p=0.04) were the independent predictors of poor treatment outcome.

Conclusions

Poor treatment outcome was observed in a considerable proportion of VL patients. Long duration of illness and coinfection with TB were associated with poor VL treatment outcome. Hence, early diagnosis and effective prompt treatment are important to improve treatment outcomes among VL patients. Special attention should also be given in the treatment of VL/TB coinfected patients in our setting.

Discovery of novel hit compounds with broad activity against visceral and cutaneous Leishmania species by comparative phenotypic screening

The limited success of recent phenotypic anti-leishmanial drug screening campaigns calls for new screening strategies for the discovery of clinically relevant hits. Here we present such a novel strategy based on physiologically relevant, ex vivo biology. We established high content phenotypic assays that combine primary murine macrophages and lesion-derived, virulent L. donovani and L. amazonensis amastigotes, which we applied to validate previously identified, anti-leishmanial hit compounds referred to as ‘GSK Leish-Box’. Together with secondary screens using cultured promastigotes, our pipeline distinguished stage- and/or species-specific compounds, including 20 hits with broad activity at 10 µM against intracellular amastigotes of both viscerotropic and dermotropic Leishmania. Even though the GSK Leish-Box hits were identified by phenotypic screening using THP-1 macrophage-like cells hosting culture-derived L. donovani LdBob parasites, our ex vivo assays only validated anti-leishmanial activity at 10 µM on intra-macrophagic L. donovani for 23 out of the 188 GSK Leish-Box hits. In conclusion, our comparative approach allowed the identification of hits with broad anti-leishmanial activity that represent interesting novel candidates to be tested in animal models. Physiologically more relevant screening approaches such as described here may reduce the very high attrition rate observed during pre-clinical and clinical phases of the drug development process.

Treatment outcomes of visceral leishmaniasis in Ethiopia from 2001 to 2017: a systematic review and meta-analysis

Background

Ethiopia has the highest number of visceral leishmaniasis (VL) cases after Sudan in Sub-Saharan Africa. However, there was lack of comprehensive data on VL treatment outcome despite the huge burden of the diseases in the country. Hence, we aimed to perform a systematic review and meta-analysis on this topic to obtain stronger evidence on treatment outcomes of VL from the existing literature in Ethiopia.

Methods

The Cochrane guidelines to conduct meta-analysis following the Preferred Reporting Items for Systematic review and Meta-Analysis statement was used to conduct a computerized systematic search of the PubMed, Google Scholar, and ScienceDirect databases. Random effects model was used to combine studies showing heterogeneity of Cochrane Q P < 0.10 and I² > 50. Treatment outcomes were assessed at end of treatment and at 6 months follow-up. Subgroup analyses were performed on treatment outcomes based on the different antileishmanial treatment options and patients’ HIV status.

Results

Fifteen studies were included in the final analyses. At end of treatment, an overall treatment success rate of 82.6% was noticed. At 6 months follow-up, the overall treatment success rate was 72.2%. For patients treated with sodium stibogluconate (SSG), the treatment success rates at the end of treatment and at six-month follow-up were 81.5% and 80.7%, respectively. Multiple doses of liposomal-amphotericin B (L-AMB) had treatment success rates of 96.7 and 71–100% at the end of treatment and at 6 months follow-up, respectively. The combination of SSG with paromomycin (PM) gave treatment success rates of up to 90.1% at the end of treatment. HIV-infected individuals were found to have a higher mortality (odds ratio = 4.77, 95% CI: 1.30–17.43, P = 0.009) rate at 6 months follow-up.

Conclusions

SSG alone has shown lower treatment efficacy in the management of VL when compared to combination of SSG with PM and multiple doses of L-AMB. The combination of SSG with PM gave good treatment success rates with shorter duration of treatment. Hence, the combination of SSG with PM should be used preferentially over SSG monotherapy. Multiple doses of L-AMB showed great efficacy especially among patients with complications, severe disease, HIV co-infection, and intolerance to the adverse effects of antimonials. HIV-infected individuals had a worse prognosis than their HIV-negative counterparts.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0491-7) contains supplementary material, which is available to authorized users.

A preliminary survey of major diseases of ruminants and management practices in Western Tigray province, northern Ethiopia

BACKGROUND

Despite the highest population, the productivity of Ethiopian livestock is low, and the direct contribution to the national economy is limited. Poor genetic potential, shortage of feed in quantity and quality, poor health care and management practices are the main contributors to low productivity and production. Data on animal disease and management practices are not in place, in this regard; we estimate the burden of animal health ailments and management practices in ruminants via simple cross-sectional study design in randomly selected peasant associations in western Tigray of northern Ethiopia.

RESULTS

A preliminary disease survey in ruminants and their management practices comprising of cattle, sheep and goats was undertaken to evaluate the existence, burden of ruminant diseases and management practices. A total of 121 randomly selected household respondents of Maikhadrah and Bakhar (26.2%), Dansha (19.7%), Adi-Hirdi (18.0%), Adi-Remets and Inda-Selassie (36.1%) sub-districts were inspected throughout the study period. Most (81%) of farmers feed their animals on free grazing in the open environment travelling from highlands and midlands to lowlands in search of adequate feed (different species of grasses) and crop residues during the wet season up to the beginning of the dry season. Majority of farmers (43.8%) had veterinary access from governmental veterinary officers. Thirty-four (33.9%) of the respondents got veterinary access from illegal drug dealers in mini shops or market. Among the major disease constraints identified; Tick infestation (89.3%), lice infestation (68.6%) mange mite infestation (77.7%) lumpy skin disease (LSD) (42.1%), trypanasomiasis (62.8%) bovine pasteurellosis (52.1) mastitis (13.2%), sheep and goat pox (15.7), abortion (19.0%), dystocia (24.8%), retained fetal membrane (25.6%), prolapsed uterus (13.2%) delayed heat period (38.8%) were most endemic ailments directly affecting livestock production and farmers livelihood.

CONCLUSION

In conclusion management practices in livestock production is poor to a large extent. Burden and endemicity of livestock diseases are substantially higher. The data obtained could be the source of facts for planners in animal health service delivery system in this sub region.

Leishmaniasis in Ethiopia: A systematic review and meta-analysis of prevalence in animals and humans

Leishmaniasis is a neglected tropical disease caused by obligate intracellular protozoa of the genus Leishmania. Ethiopia does not have an overall estimation of prevalence of leishmaniasis infection at a country level. The objective of this systematic review and meta-analysis was to summarize and pool estimates of studies that report the prevalence of leishmaniasis in Ethiopia. The literature search was conducted to identify all published studies reporting the prevalence of leishmaniasis with clearly designed inclusion and exclusion criteria. From all screened articles, 30 studies were eligible for final meta-analysis and systematic review. Because substantial heterogeneity was expected, random-effects meta-analyses were carried out using the total sample size and number of positives to estimate the prevalence of the disease at a country level. Between-study variability was high (τ² = 0.02; heterogeneity I² = 99.72% with Heterogeneity chi-square = 11985.41, a degree of freedom = 33 and P = 0.001). The overall random pooled prevalence of leishmaniasis was 19% (95% CI 14%-24%). Meta-regression analysis showed that diagnosis method used have contributed to the heterogeneity of studies. Molecular diagnosis has significantly lower prevalence than microscopic examination with a coefficient of -0.32, a p-value of 0.024, and CI (-0.6-0.05). The result of effect estimates against its standard error showed there was no publication bias with a P value of 0.084. This review indicated that there is still a higher prevalence of Leishmaniasis in the country. Reporting on risk factors like sex and age affected, species of Leishmania involved and many more other risk factors reviewing was not possible in this study due to lack of completeness in articles included. However, this report is an indication that the country needs nationally coordinated extensive prevention and control plan to reduce public health and socio-economic impact of the disease.

The criminal association of Leishmania parasites and viruses

In nature, humans infected with protozoan parasites can encounter viruses, which could alter their host immune response. The impact of viruses on human parasitic diseases remains largely unexplored due to the highly sterilized environment in experimental studies and the difficulty to draw a correlation between co-infection and pathology. Recent studies show that viral infections exacerbate pathology and promote dissemination of some Leishmania infections, based on a hyper-inflammatory reaction driven by type I interferons. Thus, not only the infecting parasite species, but also bystander viral infections could be a major determinant of the outcome of Leishmania infection. In this review, we focus on the contribution of viral co-infection to the exacerbation of leishmaniasis's pathology and its possible impact on treatment and vaccination strategies.