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1.
Proteome Sci ; 18(1): 10, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33292280

RESUMO

BACKGROUND: Tuberculosis (TB) is one of the world's most problematic infectious diseases. The pathogen Mycobacterium tuberculosis (Mtb) is contained by the immune system in people with latent TB infection (LTBI). No overt disease symptoms occur. The environmental and internal triggers leading to reactivation of TB are not well understood. Non-tuberculosis Mycobacteria (NTM) can also cause TB-like lung disease. Comparative analysis of blood plasma proteomes from subjects afflicted by these pathologies in an endemic setting may yield new differentiating biomarkers and insights into inflammatory and immunological responses to Mtb and NTM. METHODS: Blood samples from 40 human subjects in a pastoral region of Ethiopia were treated with the ESAT-6/CFP-10 antigen cocktail to stimulate anti-Mtb and anti-NTM immune responses. In addition to those of active TB, LTBI, and NTM cohorts, samples from matched healthy control (HC) subjects were available. Following the generation of sample pools, proteomes were analyzed via LC-MS/MS. These experiments were also performed without antigen stimulation steps. Statistically significant differences using the Z-score method were determined and interpreted in the context of the proteins' functions and their contributions to biological pathways. RESULTS: More than 200 proteins were identified from unstimulated and stimulated plasma samples (UPSs and SPSs, respectively). Thirty-four and 64 proteins were differentially abundant with statistical significance (P < 0.05; Benjamini-Hochberg correction with an FDR < 0.05) comparing UPS and SPS proteomic data of four groups, respectively. Bioinformatics analysis of such proteins via the Gene Ontology Resource was indicative of changes in cellular and metabolic processes, responses to stimuli, and biological regulations. The m7GpppN-mRNA hydrolase was increased in abundance in the LTBI group compared to HC subjects. Charged multivesicular body protein 4a and platelet factor-4 were increased in abundance in NTM as compared to HC and decreased in abundance in NTM as compared to active TB. C-reactive protein, α-1-acid glycoprotein 1, sialic acid-binding Ig-like lectin 16, and vitamin K-dependent protein S were also increased (P < 0.05; fold changes≥2) in SPSs and UPSs comparing active TB with LTBI and NTM cases. These three proteins, connected in a STRING functional network, contribute to the acute phase response and influence blood coagulation. CONCLUSION: Plasma proteomes are different comparing LTBI, TB, NTM and HC cohorts. The changes are augmented following prior blood immune cell stimulation with the ESAT-6/CFP-10 antigen cocktail. The results encourage larger-cohort studies to identify specific biomarkers to diagnose NTM infection, LTBI, and to predict the risk of TB reactivation.

2.
Glob Health Action ; 13(1): 1841963, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33200686

RESUMO

The Coronavirus pandemic is recording unprecedented deaths worldwide. The temporal distribution and burden of the disease varies from setting to setting based on economic status, demography and geographic location. A rapid increase in the number of COVID-19 cases is being reported in Africa as of June 2020. Ethiopia reported the first COVID-19 case on 13 March 2020. Limited molecular laboratory capacity in resource constrained settings is a challenge in the diagnosis of the ever-increasing cases and the overall management of the disease. In this article, the Ethiopian Public Health Institute (EPHI) shares the experience, challenges and prospects in the rapid establishment of one of its COVID-19 testing laboratories from available resources. The first steps in establishing the COVID-19 molecular testing laboratory were i) identifying a suitable space ii) renovating it and iii) mobilizing materials including consumables, mainly from the Malaria and Neglected Tropical Diseases (NTDs) research team at the EPHI. A chain of experimental design was set up with distinct laboratories to standardize the extraction of samples, preparation of the master mix and detection. At the commencement of sample reception and testing, laboratory contamination was among the primary challenges faced. The source of the contamination was identified in the master mix room and resolved. In summary, the established COVID-19 testing lab has tested more than 40,000 samples (August 2020) and is the preferred setting for research and training. The lessons learned may benefit the further establishment of emergency testing laboratories for COVID-19 and/or other epidemic/pandemic diseases in resource-limited settings.

3.
BMC Infect Dis ; 20(1): 750, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33050903

RESUMO

BACKGROUND: Tuberculosis (TB) is caused by Mycobacterium tuberculosis complex (MTBC). Mapping the genetic diversity of MTBC in high TB burden country like Ethiopia is important to understand principles of the disease transmission and to strengthen the regional TB control program. The aim of this study was to investigate the genetic diversity of Mycobacterium tuberculosis complex (MTBC) isolates circulating in the South Omo, southern Ethiopia. METHODS: MTBC isolates (N = 156) were genetically analyzed using spacer oligotyping (spoligotyping) and mycobacterial interspersed repetitive unit-variable number of tandem repeat (MIRU-VNTR) typing. Major lineages and lineages were identified using MTBC databases. Logistic regression was used to correlate patient characteristics with strain clustering. RESULTS: The study identified Euro-American (EA), East-African-Indian (EAI), Indo-Oceanic (IO), Lineage_7/Aethiops vertus, Mycobacterium bovis and Mycobacterium africanum major lineages in proportions of 67.3% (105/156), 22.4% (35/156), 6.4% (10/156), 1.9% (3/156), 1.3% (2/156) and 0.6% (1/156), respectively. Lineages identified were Delhi/CAS 23.9% (37/155), Ethiopia_2 20.6% (32/155), Haarlem 14.2% (22/155), URAL 14.2%(22/155), Ethiopia_3 8.4% (13/155), TUR 6.5% (10/155), Lineage_7/Aethiops vertus 1.9% (3/155), Bovis 1.3% (2/155), LAM 1.3% (2/155), EAI 0.6% (1/155), X 0.6% (1/155) and Ethiopia H37Rv-like strain 0.6% (1/155). Of the genotyped isolates 5.8% (9/155) remained unassigned. The recent transmission index (RTI) was 3.9%. Orphan strains compared to shared types (AOR: 0.09, 95% CI: 0.04-0.25) were associated with reduced odds of clustering. The dominant TB lineage in pastoral areas was EAI and in non-pastoral areas was EA. CONCLUSION: The epidemiological data, highly diverse MTBC strains and a low RTI in South Omo, provide information contributing to the TB Control Program of the country.


Assuntos
Variação Genética , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Etiópia/epidemiologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites/genética , Epidemiologia Molecular , Reação em Cadeia da Polimerase Multiplex , Mycobacterium bovis/isolamento & purificação , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/microbiologia , Adulto Jovem
4.
Infect Immun ; 88(12)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32958527

RESUMO

Cell (CD3+ T cell and CD68+ macrophages), cytokine (interferon gamma-positive [IFN-γ+] and tumor necrosis factor alpha-positive [TNF-α+]), and effector molecule (inducible nitric oxide synthase-positive [iNOS+]) responses were evaluated in the lymph nodes and tissues of cattle naturally infected with Mycobacterium bovis Detailed postmortem and immunohistochemical examinations of lesions were performed on 16 cows that were positive by the single intradermal cervical comparative tuberculin (SICCT) test and that were identified from dairy farms located around the city of Addis Ababa, Ethiopia. The severity of the gross lesion was significantly higher (P = 0.003) in M. bovis culture-positive cows (n = 12) than in culture-negative cows (n = 4). Immunohistochemical techniques showed that in culture-positive cows, the mean immunolabeling fraction of CD3+ T cells decreased as the stage of granuloma increased from stage I to stage IV (P < 0.001). In contrast, the CD68+ macrophage, IFN-γ+, TNF-α+, and iNOS+ immunolabeling fractions increased from stage I to stage IV (P < 0.001). In the early stages, culture-negative cows showed a significantly higher fraction of CD68+ macrophage (P = 0.03) and iNOS+ (P = 0.007) immunolabeling fractions than culture-positive cows. Similarly, at advanced granuloma stages, culture-negative cows demonstrated significantly higher mean proportions of CD3+ T cells (P < 0.001) than culture-positive cows. Thus, this study demonstrates that, following natural infection of cows with M. bovis, as the stage of granuloma increases from stage I to stage IV, the immunolabeling fraction of CD3+ cells decreases, while the CD68+ macrophage, IFN-γ+, TNF-α+, and iNOS+ immunolabeling fractions increases.

5.
PLoS One ; 15(5): e0233314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428042

RESUMO

BACKGROUND: Latent tuberculosis infection (LTBI) is the major source of active TB and is an obstacle to the strategy of World Health Organization to end TB by 2035. In Ethiopia, there are hundreds of prisons and they are conducive settings for the transmission of TB and could serve as the sources of infection to the general public. However, there is little data on the epidemiology of TB in prisons in Ethiopia. The objective of the present study was to estimate the prevalence of LTBI and evaluate associated risk factors in prisons in East Wollega Zone in western Ethiopia. METHODS: A cross-sectional design and systematic sampling technique were used to select 352 prisoners from a total of 2620 prisoners during the two months (May and June, 2019). The selected inmates were consented for their willingness to participate in the study. Thereafter, they were interviewed and 2ml of blood sample was collected from each prisoner and screened for LTBI using interferon-gamma release assay (IGRA). The data were analyzed using SPSS version 25 and logistic regression was used to model the likelihood of LTBI occurrence and to identify risk factors associated with LTBI. RESULTS: The prevalence of LTBI was 51.2% (95% CI: 46.45-57%) and higher prevalence was recorded in males (53%) than in females (43.5%) although the difference was not significant. Prisoners whose age ≥45 years (AOR = 2.48, 95%CI, 1.04-5.9), who chewed khat (AOR = 2.27; 95% CI, 1.27-4.19), who were prisoned over a year (AOR = 1.81, 95%CI, 1.04-3.18) and who were in overcrowded pens (AOR = 1.91, 95% CI, 1.002-3.65) were at higher risk of LTBI. CONCLUSIONS: The prevalence of LTBI in prisoners in West Wollega Zone of western Ethiopia was high and could serve as sources of infection to the public. Hence optimum handling of prisoners, and regular follow up and treatment of TB cases in prisons were recommended to minimize the burden of TB in the Zone.


Assuntos
Tuberculose Latente/epidemiologia , Adolescente , Adulto , Criança , Estudos Transversais , Etiópia/epidemiologia , Feminino , Humanos , Testes de Liberação de Interferon-gama , Tuberculose Latente/metabolismo , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Prisioneiros/estatística & dados numéricos , Prisões/estatística & dados numéricos , Fatores de Risco , Teste Tuberculínico , Tuberculose/epidemiologia , Tuberculose/metabolismo , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/metabolismo , Adulto Jovem
6.
Tuberc Res Treat ; 2019: 2106981, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737364

RESUMO

Background: Tuberculosis (TB) has been an important public health concern in Ethiopia, particularly at areas of human-animal intersection. However, limited epidemiological information is available in this respect in the country. Therefore, the present study was conducted to investigate the transmission of TB at human-cattle interface, associated risk factors and public awareness about the disease at South Gondar Zone, northwest Ethiopia. Methods: A cross sectional study was conducted between March 2015 and April 2018 on 186 farmers and 476 cattle in South Gondar Zone, northwest Ethiopia. Bacteriological examination, region of difference (RD) 9-based polymerase chain reaction (PCR), single intradermal comparative tuberculin test (SICTT), and questionnaire were used for undertaking this study. Results: Culture positivity in farmers was 59.7% (111/186) and all the culture positive isolates were M. tuberculosis. About 68% (74/111) of culture positive respondents did not know about the transmission of TB from cattle to human or vice versa. The animal and herd prevalence of bovine TB were 1.5% (7/476) and 7.4% (7/95), respectively. Although the result was not statistically significant, the odds of bovine TB in cattle owned by TB positive households was slightly higher than those owned by TB free households (adjusted odds ratio, AOR = 1.39; 95% CI: 0.31-7.10; p = 0.76). Conclusion: Although SIDCTT reactivity was slightly higher in cattle owned by TB positive households, all the human isolates were M. tuberculosis and no M. bovis was isolated from farmers, which could be due to the low prevalence of bovine TB in the area.

7.
BMC Vet Res ; 15(1): 359, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640672

RESUMO

BACKGROUND: Bovine tuberculosis (bTB) is prevalent in dairy cattle in Ethiopia. Currently used diagnostic tools such as the single intradermal comparative tuberculin test (SICTT) are time consuming and labor intensive. A rapid, easy-to-use and cost-effective diagnostic test would greatly contribute to the control of bTB in developing countries like Ethiopia. In the present study, two point-of-care diagnostic tests were evaluated for the detection of bTB: LIONEX® Animal TB Rapid test, a membrane-based test for the detection of antibodies to Mycobacterium bovis in blood and ALERE® Determine TB Lipoarabinomannan (LAM) Ag, an immunoassay for the detection of lipoarabinomannan (LAM) antigen (Ag) of mycobacteria in urine. A combination of the SICTT and gamma interferon (IFN-γ) test was used as the gold standard for the validation of these point-of-care tests, as it was not feasible to slaughter the study animals to carry out the historical gold standard of mycobacterial culture. A total of 175 heads of cattle having three different bTB infection categories (positive SICTT, negative SICTT, and unknown SICTT status) were used for this study. RESULT: The sensitivity and specificity of TB LAM Ag were 72.2% (95% CI = 62.2, 80.4) and 98.8% (95% CI = 93.6, 99.7), respectively, while the sensitivity and specificity of the LIONEX Animal TB rapid test assay were 54% (95% CI = 44.1 64.3) and 98.8% (95% CI = 93.6, 99.7) respectively. The agreement between TB LAM Ag and SICTT was higher (κ = 0.85; 95% CI = 0.65-0.94) than between TB LAM Ag and IFN-γ (κ = 0.67; 95% CI = 0.52-0.81). The agreement between LIONEX Animals TB Rapid blood test and SICTT was substantial, (κ = 0.63; 95% CI = 0.49-0.77) while the agreement between LIONEX Animal TB rapid blood test and IFN-γ test was moderate (κ = 0.53; 95% CI = 0.40-0.67). Analysis of receiver operating curve (ROC) indicated that the area under the ROC curve (AUC) for TB LAM Ag was 0.85 (95% CI = 0.79-0.91) while it was 0.76 (95% CI; =0.69-0.83) for LIONEX Animal TB rapid test assay. CONCLUSION: This study showed that TB LAM Ag had a better diagnostic performance and could potentially be used as ancillary either to SICTT or IFN-γ test for diagnosis of bTB.


Assuntos
Imunoensaio/veterinária , Lipopolissacarídeos/sangue , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Bovina/diagnóstico , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Etiópia , Interferon gama/sangue , Lipopolissacarídeos/imunologia , Mycobacterium tuberculosis/imunologia , Sensibilidade e Especificidade , Teste Tuberculínico/veterinária , Tuberculose Bovina/sangue , Tuberculose Bovina/imunologia
8.
Sci Adv ; 5(7): eaax4899, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328169

RESUMO

Bovine tuberculosis (bTB) is a major zoonotic disease of cattle that is endemic in much of the world, limiting livestock productivity and representing a global public health threat. Because the standard tuberculin skin test precludes implementation of Bacille Calmette-Guérin (BCG) vaccine-based control programs, we here developed and evaluated a novel peptide-based defined antigen skin test (DST) to diagnose bTB and to differentiate infected from vaccinated animals (DIVA). The results, in laboratory assays and in experimentally or naturally infected animals, demonstrate that the peptide-based DST provides DIVA capability and equal or superior performance over the extant standard tuberculin surveillance test. Together with the ease of chemical synthesis, quality control, and lower burden for regulatory approval compared with recombinant antigens, the results of our studies show that the DST considerably improves a century-old standard and enables the development and implementation of critically needed surveillance and vaccination programs to accelerate bTB control.


Assuntos
Antígenos de Bactérias/imunologia , Bovinos/microbiologia , Testes Cutâneos , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/imunologia , Animais , Interferon gama/metabolismo , Peptídeos/imunologia , Teste Tuberculínico
9.
PLoS One ; 14(6): e0218545, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31233535

RESUMO

BACKGROUND: Tuberculosis (TB) is one of the major public health problems in Ethiopia. Data on genetic diversity and resistance profile of circulating TB strains is critical for informing the national TB control program. METHODS: A cross-sectional study was conducted on 213 smear positive pulmonary TB patients between 2015 and 2016. Sputum samples were cultured on LJ media following the Petroff's method. Region of difference-9 (RD9)-deletion typing and spoligo-typing were performed for molecular analysis of M. tuberculosis at species and strain levels, respectively. Drug sensitivity and mutation patterns of the isolates were assessed by the conventional indirect proportion method and molecular line probe assays (LPAs), respectively. Data were analyzed using statistical package for social sciences (SPSS) software version 20. RESULTS: Spoligo-typing of 150 M. tuberculosis isolates led to 57 different patterns of which 25 were new strains. The majority (71.6%) of the isolates were grouped in to 17 clusters consisting 2 to 24 isolates. The majority of the strains belonged to Euro-American lineage and the predominant spoligotypes were SIT 37 and SIT 149. MDR-TB was detected in 5.2% and 20.3% of new and retreatment cases, respectively. Two MDR-TB isolates exhibited additional resistance to one of the second line anti-TB drugs. Common gene mutations including S531L, S315T1 and M306V were detected in RIF, INH and EMB resistant strains, respectively. CONCLUSIONS: The identification of several new strains, higher proportion of MDR-TB and higher clustering rate in this study, warrants the need for re-enforcement of the national TB control program. The detection of common gene mutations in the majority drug resistant strains might suggest the feasibility of LPAs for rapid screening of drug resistant M. tuberculosis strains in Ethiopia.


Assuntos
Infecção Hospitalar , Farmacorresistência Bacteriana/efeitos dos fármacos , Variação Genética , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , Tuberculose/microbiologia , Adolescente , Adulto , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Estudos Transversais , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Mycobacterium tuberculosis/classificação , Razão de Chances , Tuberculose/tratamento farmacológico , Adulto Jovem
10.
J Vet Med ; 2019: 8315137, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941376

RESUMO

Mycobacterium bovis (M. bovis) has an exceptionally wide host range including sheep. Information on tuberculosis (TB) in sheep is scarce, and there appears to be conflicting opinions about the relative susceptibility of sheep to infection. In Ethiopia, there was no single previous report on tuberculosis in sheep, though mixed farming of cattle and sheep is a common practice. In this study, following the observation of TB-like lesions on sheep died from sheep flock kept in contact with cattle herd, further investigation was conducted on the flock to assess the magnitude of the infection and identify and characterize the causative M. bovis strain. An outbreak investigation was carried out on 26 eligible sheep out of 33 sheep found on the farm. Comparative intradermal tuberculin (CIDT) test, postmortem examination, Mycobacterium culturing, and spoligotyping were the techniques used in the study. The prevalence of TB in the tested sheep was 15% (4/26). All the sheep that were positive to CIDT had gross lesions suggestive of TB. Three of the positive sheep had extensive and multiple lesions. M. bovis was isolated from all four sheep and the strain was identified as spoligotype SBO134. The in-contact dairy cows were screened for TB and 98% (45/46) of the cows tested positive to CIDT. Furthermore, the same strain, SB0134, was also isolated from the two in-contact cows. The isolation of a matching genotype (SB0134) of M. bovis from both species sharing a known epidemiologic link strongly suggests that the sheep flock might have acquired the pathogen from the dairy cows. This warrants strict physical separation of the sheep flock from the cattle herd to prevent such interspecies transmission of M. bovis.

11.
BMC Infect Dis ; 19(1): 343, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023267

RESUMO

BACKGROUND: Drug resistant tuberculosis (TB) has become a persistent health threat in Ethiopia. In this respect, baseline data are scarce in many parts of high TB burden regions including the different zones of Ethiopia. METHODS: A total of 111 culture positive M. tuberculosis isolates were recovered from TB patients and identified using region of difference (RD) 9 based polymerase chain reaction (PCR) and spoligotyping. Thereafter, their drug sensitivities to Rifampicin (RIF) and Isoniazid (INH) were evaluated using GenoType MTBDRplus assay. RESULTS: The result showed that 18.0% (20/111) of the isolates were resistant to either RIF or INH. Furthermore, 16.7 and 23.8% of the isolates from new and retreatment cases were resistant to any of the two anti-TB drugs, respectively. Multi-drug resistant (MDR) TB was detected on 1.8% (2/111) of all cases. Significantly higher frequencies of any drug resistance were observed among Euro-American (EA) major lineage (χ2: 9.67; p = 0.046). CONCLUSION: Considerably high proportion of drug resistant M. tuberculosis strains was detected which could suggest a need for an increased effort to strengthen TB control program in the study area.


Assuntos
Tipagem Molecular/métodos , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
12.
BMC Vet Res ; 14(1): 396, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30547772

RESUMO

BACKGROUND: Bovine brucellosis is considered as an important disease among livestock and people in sub-Saharan African countries including Ethiopia. A cross-sectional study was conducted from November 2016 to May 2017 to estimate the prevalence and associated risk factors, and to assess knowledge-attitude and practices (KAP) of farm workers about bovine brucellosis in Addis Ababa dairy farms. RESULTS: A total of 1550 cattle from 127 dairy farms were serially tested using the Rose Bengal Plate Test (RBPT), Competitive Enzyme-Linked Immunosorbant Assay (c-ELISA) and Complement Fixation Test (CFT). Forty-three (2.77%) of the collected sera were positive by the RBPT and only one of these was positive by c-ELISA (0.06%) and none was positive by CFT. The knowledge of farm workers towards the disease was very low and risk factors associated with Brucella infection were apparent in the study area. CONCLUSION: Seropositivity for Brucella spp. was found in only a very small percentage by c-ELISA test, although risk factors for transmitting Brucella infection were present. The results suggest that bovine brucellosis is currently not a generalized problem in dairy cattle of Addis Ababa. Since this favorable disease situation is not the result of informed policy, there is no guarantee that it will continue unchanged. Setting clear policy in control of the disease and implementing "One Health" are the most constructive approaches recommended.


Assuntos
Brucelose Bovina/epidemiologia , Técnicas e Procedimentos Diagnósticos/veterinária , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Estudos Transversais , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática , Etiópia/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos
13.
Trop Anim Health Prod ; 50(7): 1665-1670, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29721803

RESUMO

Dromedary camels are the main sources of milk, meat and income for the Ethiopian pastoralists as they withstand the harsh environments of the regions of the country. Tuberculosis (TB) affects dromedary camels causing morbidity and mortality in these animals. Hence, early diagnosis and identification of infected camels play a significant role in reducing the transmission of TB in camels. This study was conducted on 168 camels between October 2014 and July 2015 to evaluate the performance of single intra-dermal comparative cervical tuberculin (SICCT) to diagnose TB in camels. Gross pathology was used as a gold standard to define disease status of each camel. The result showed that at the cutoff value of ≥ 3 mm SICCT had optimum performance with sensitivity and specificity of 60.7 and 85%, respectively. Moreover, at a cutoff ≥ 3 mm, the receiver operating characteristics (ROC) revealed area under the ROC curve was 0.729 (0.615-0.842) which is statistically significant (p = 0.000). Thus, the result of the present study could suggest the use of ≥ 3 mm cutoff value for the diagnosis of TB in dromedary camels in Ethiopia.


Assuntos
Camelus/microbiologia , Teste Tuberculínico/veterinária , Tuberculose/diagnóstico , Tuberculose/veterinária , Matadouros , Criação de Animais Domésticos/métodos , Animais , Área Sob a Curva , Estudos Transversais , Etiópia/epidemiologia , Feminino , Geografia , Gado , Masculino , Curva ROC , Padrões de Referência , Sensibilidade e Especificidade , Tuberculose/epidemiologia , Tuberculose/transmissão
14.
BMC Public Health ; 18(1): 266, 2018 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-29454325

RESUMO

BACKGROUND: Research pertaining to the community-based prevalence of latent tuberculosis infection (LTBI) is important to understand the magnitude of this infection. This study was conducted to estimate LTBI prevalence and to identify associated risk factors in the Omo Zone of Southern Ethiopia. METHODS: A community-based cross-sectional study was conducted in six South Omo districts from May 2015 to February 2016. The sample size was allocated to the study districts proportional to their population sizes. Participants were selected using a multi-stage sampling approach. A total of 497 adult pastoralists were recruited. Blood samples were collected from the study participants and screened for LTBI using a U.S. Food and Drug Administration approved interferon-gamma release assay (IGRA). Logistic regression was used to model the likelihood of LTBI occurrence and to identify risk factors associated with LTBI. RESULTS: The prevalence of LTBI was 50.5% (95% CI: 46%, 55%) with no significant gender difference (49.8% among males versus 51.2% among females; Chi-square (χ2) = 0.10; P = 0.41) and marginally non-significant increasing trends with age (44.6% among those below 24 years and 59.7% in the age range of 45-64 years; χ2 = 6.91; P = 0.075). Being residence of the Dasanech District (adjusted odds ratio, AOR = 2.62, 95% CI: 1.30, 5.28; P = 0.007) and having a habit of eating raw meat (AOR = 2.89, 95% CI: 1.09, 7.66; P = 0.033) were significantly associated with an increased odds of being positive for LTBI. A large family size (size of 5 to 10) has significant protective effect against associated a reduced odds of being positive for LTBI compared to a family size of below 5 (AOR = 0.65, 95% CI: 0.42, 0.99; P = 0.045). CONCLUSIONS: A high prevalence of LTBI in the South Omo Zone raises the concern that elimination of TB in the pastoral communities of the region might be difficult. Screening for and testing individuals infected with TB, independent of symptoms, may be an effective way to minimize the risk of disease spread.


Assuntos
Tuberculose Latente/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criação de Animais Domésticos , Estudos Transversais , Etiópia/epidemiologia , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Adulto Jovem
15.
PLoS One ; 13(2): e0193083, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29447273

RESUMO

INTRODUCTION: Tuberculosis (TB) is caused by M. tuberculosis complex and remains a major global public health problem. The epidemic remains a threat to sub-Saharan Africa, including Ethiopia, with further emergence of drug resistant TB. We investigated the drug sensitivity pattern and molecular epidemiology of mycobacterial strains isolated from pulmonary TB patients in and around Ambo town in Oromia Region, Central Ethiopia. METHODS: A cross-sectional study was conducted involving 105 consecutive new smear positive pulmonary TB patients diagnosed at Ambo Hospital and surrounding Health Centers between May 2014 and March 2015 upon informed consent. Sputum samples were cultured on Löwenstein-Jensen (LJ) media using standard techniques to isolate mycobacteria. Region of difference 9 (RD9)-based polymerase chain reaction (PCR) and spoligotyping was employed for the identification of the isolates at species and strain levels. The spoligotype patterns were entered into the SITVIT database to determine Octal and SIT (Spoligotyping International Typing) numbers for each strain. The sensitivity of the isolates to isoniazid (INH), rifampicin (RIF), ethambutol (ETB) and streptomycin (STM) was evaluated on LJ-medium with the indirect proportion method. RESULTS: Cultures were positive in 86/105 (82%) of newly diagnosed smear positive pulmonary TB cases. All of the 86 isolates were confirmed as M. tuberculosis. The majority (76.7%) of them were clustered into seven groups while the rest (23.3%) appeared unique. The most predominant Spoligotypes were SIT53 and SIT149, consisting of 24.4% and 20.9% of the isolates, respectively. Assigning of the isolates to family using SPOTCLUST software revealed that 45.3% of the isolates belonged to T1, 23.3% to T3 and 13% to CAS family. The majority (76.7%) of the M. tuberculosis isolates were susceptible to all the four drugs. Any resistance to any one of the four drugs was detected in 23.3% of the isolates. The highest proportion of any resistance was observed against isoniazid (9.3%) and ethambutol (7%). There was only a single case (1.2%) of multidrug resistant/rifampicin resistant (MDR/RR) TB. CONCLUSION: The majority of the isolates were clustered suggesting on-going active transmission in the study area. Mono resistance is relatively prevalent while the magnitude of MDR/RR-TB was found to be lower than in previous studies.


Assuntos
Mycobacterium tuberculosis/genética , RNA Viral/genética , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Estudos Transversais , Etambutol/farmacologia , Etambutol/uso terapêutico , Etiópia/epidemiologia , Feminino , Humanos , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Epidemiologia Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/farmacologia , Rifampina/uso terapêutico , Estreptomicina/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/microbiologia , Adulto Jovem
16.
Infect Immun ; 86(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29311240

RESUMO

Accurate diagnosis and early treatment of tuberculosis (TB) and latent TB infection (LTBI) are vital to prevent and control TB. The lack of specific biomarkers hinders these efforts. This study's purpose was to screen immunological markers that discriminate Mycobacterium tuberculosis infection outcomes in a setting where it is endemic, Ethiopia. Whole blood from 90 participants was stimulated using the ESAT-6/CFP-10 antigen cocktail. The interferon gamma (IFN-γ)-based QuantiFERON diagnostic test was used to distinguish between LTBI and uninfected control cases. Forty cytokines/chemokines were detected from antigen-stimulated plasma supernatants (SPSs) and unstimulated plasma samples (UPSs) using human cytokine/chemokine antibody microarrays. Statistical tests allowed us to identify potential biomarkers that distinguish the TB, LTBI, and healthy control groups. As expected, the levels of IFN-γ in SPSs returned a high area under the receiver operating characteristic curve (AUC) value comparing healthy controls and LTBI cases (Z = 0.911; P < 0.001). The SPS data also indicated that interleukin 17 (IL-17) abundance discriminates LTBI from healthy controls (Z = 0.763; P = 0.001). RANTES and MIP-1ß were significantly elevated in SPSs of TB-infected compared to healthy controls (P < 0.05), while IL-12p40 and soluble tumor necrosis factor receptor II (sTNF-RII) were significantly increased in active TB cases compared to the combined LTBI and control groups (P < 0.05). Interestingly, quantitative changes for RANTES were observed using both SPSs and UPSs, with P values of 0.013 and 0.012, respectively, in active TB versus LTBI cases and 0.001 and 0.002, respectively, in active TB versus healthy controls. These results encourage biomarker verification studies for IL-17 and RANTES. Combinations of these cytokines may complement IFN-γ measurements to diagnose LTBI and distinguish active TB from LTBI cases.


Assuntos
Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Adulto , Biomarcadores , Estudos de Casos e Controles , Citocinas/sangue , Citocinas/metabolismo , Etiópia/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Tuberculose/epidemiologia , Tuberculose/metabolismo , Adulto Jovem
17.
BMC Vet Res ; 13(1): 237, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28810868

RESUMO

BACKGROUND: The main cause of bovine tuberculosis (bTB) is believed to be Mycobacterium bovis (M. bovis). Nontuberculosis mycobacteria (NTM) are neglected but opportunistic pathogens and obstacles for bTB diagnosis. This study aimed to isolate and characterize the mycobacteria organisms involved in causing TB-like lesions in cattle in northwestern Ethiopia. RESULTS: A total of 2846 carcasses of cattle were inspected for TB lesions. Ninety six tissues (including lymph nodes such as submandibular, retropharyngeal, tonsilar, mediatinal, bronchial and mesenteric, and organs such as lung, liver and kidney) with suspicious TB lesion(s) were collected and cultured on Lowenstein-Jensen medium. Twenty one showed culture growth, of which only 17 were identified containing acid fast bacilli (AFB) by Ziehl-Neelsen staining. Among the 17 AFB isolates 15 generated a polymerase chain reaction product of 1030 bp by gel electrophoresis based on the 16S ribosomal RNA gene amplification. No M. tuberculosis complex species were isolated. Further characterization by Genotype Mycobacterium CM assay showed 6 isolates identified as M. peregrinum. Eight isolates represented by mixed species, which includes M. fortuitum-peregrinum (3 isolates), M. gordonae-peregrinum (3 isolates) and M. fortuitum-gordonae-peregrinum (2 isolates). One NTM could not be interpreted. CONCLUSION: A significant number of NTM species were isolated from TB-like lesions of grazing cattle slaughtered at Bahir Dar Abattoir. Such finding could suggest the role of NTM in causing lesions in cattle. Further investigations are recommended on the pathogenesis of the reported NTM species in cattle, and if they have public health significance.


Assuntos
Doenças dos Bovinos/microbiologia , Infecções por Mycobacterium não Tuberculosas/veterinária , Micobactérias não Tuberculosas/classificação , Matadouros , Animais , Bovinos , Etiópia/epidemiologia , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico 16S
18.
BMC Res Notes ; 10(1): 31, 2017 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-28061860

RESUMO

BACKGROUND: The feeding habits and close physical contact between Ethiopian farmers and their cattle promote the transmission of tuberculosis (TB) between the farmers and their cattle. This study aimed to investigate the transmission of TB between farmers and their cattle in smallholder farms in northwestern Ethiopia. RESULTS: A total of 70 human TB lymphadenitis (TBLN) cases visiting the Felegehiwot Comprehensive Specialized Hospital in Bahir Dar City and 660 cattle were investigated. Half of the cattle were owned by households with TB cases, and the remaining half by TB free households. Among the 70 human TBLN patients interviewed, 65.7% (46 out of 70) of the respondents were not aware of zoonotic TB, and 67.1% (47/70) of them consumed raw milk. Positive cultures of TB were obtained in 40 of the 70 cases where TBLN tests were positive with fine needle aspiration cytology. Spoligotyping resulted in 31 different patterns, of which 25 isolates were Mycobacterium (M.) tuberculosis, and the remaining were M. africanum (4 isolates) and M. bovis (2 isolates). None of the animals showed positive test results for bovine TB by comparative intradermal tuberculin test. CONCLUSIONS: Based on the identification of M. bovis from two patients diagnosed with TBLN, we obtained preliminary evidence of zoonotic transmission of TB in northwestern Ethiopia. We did not identify a direct route of transmission between cattle and its owners. This is the objective of further investigations.


Assuntos
Fazendeiros , Tuberculose Bovina/transmissão , Tuberculose dos Linfonodos/transmissão , Tuberculose/transmissão , Zoonoses/transmissão , Animais , Biópsia por Agulha Fina , Bovinos , Estudos Transversais , Etiópia , Contaminação de Alimentos , Microbiologia de Alimentos , Humanos , Mycobacterium bovis , Exposição Ocupacional , Tuberculina/química , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/microbiologia , Tuberculose dos Linfonodos/diagnóstico , Tuberculose dos Linfonodos/microbiologia , Zoonoses/diagnóstico , Zoonoses/microbiologia
19.
Parasit Vectors ; 9: 218, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27090082

RESUMO

BACKGROUND: Epidemiological studies in Ethiopia have documented that the risk of visceral leishmaniasis (VL, Kala-azar) is higher among people living with domestic animals. The recent report on isolation of Leishmania donovani complex DNA and the detected high prevalence of anti-leishmanial antibodies in the blood of domestic animals further strengthen the potential role of domestic animals in the epidemiology of VL in Ethiopia. In mammalian hosts polymorphonuclear cells (PMN) and macrophages are the key immune cells influencing susceptibility or control of Leishmania infection. Thus to substantiate the possible role of cattle in VL transmission we investigate the permissiveness of bovine PMN and monocyte derived macrophages (MDM) for Leishmania (L.) donovani infection. METHODS: Whole blood was collected from pure Zebu (Boss indicus) and their cross with Holstein Friesian cattle. L. donovani (MHOM/ET/67/HU3) wild and episomal green fluorescent protein (eGFP) labelled stationary stage promastigotes were co-incubated with whole blood and MDM to determine infection of these cells. Engulfment of promastigotes by the cells and their transformation to amastigote forms in MDM was studied with direct microscopy. Microscopy and flow cytometry were used to measure the infection rate while PCR-RLFP was used to confirm the infecting parasite. RESULTS: L. donovani infected bovine whole blood PMN in the presence of plasma factors and all cellular elements. Morphological examinations of stained cytospin smears revealed that PMN engulfed promastigotes. Similarly, we were able to show that bovine MDM can be infected by L. donovani, which transformed to amastigote forms in the cells. CONCLUSIONS: The in vitro infection of bovine PMN and MDM by L. donovani further strengthens the possibility that cattle might serve as source of L. donovani infection for humans.


Assuntos
Doenças dos Bovinos/parasitologia , Leishmania donovani/fisiologia , Leishmaniose Visceral/veterinária , Macrófagos/parasitologia , Neutrófilos/parasitologia , Animais , Bovinos , Doenças dos Bovinos/imunologia , Etiópia , Leishmania donovani/genética , Leishmania donovani/isolamento & purificação , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Macrófagos/imunologia , Neutrófilos/imunologia
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