Asseged Bogale

Molecular characterization of Mycobacterium bovis isolates from Ethiopian cattle

BackgroundBovine Tuberculosis (BTB) is a widespread and endemic disease of cattle in Ethiopia. Information relating to genotypic characteristics of Mycobacterium bovis strains affecting the cattle population in Ethiopia is limited. We carried out molecular characterization of M. bovis strains isolated from BTB infected cattle using the spoligotyping technique. The relationship between distribution of spoligotypes and recorded variables was also investigated. A new approach that can numerically reflect the degree of genetic polymorphism in a M. bovis population was also developed. The study was conducted from July 2006 to January 2007 in cattle slaughtered at five representative abattoirs in Ethiopia.ResultsForty-five M. bovis isolates were obtained from 406 pathologic tissue specimens collected from 337 carcasses with lesions compatible with BTB. Twelve spoligotypes were identified from 34 distinct strains; with SB1176 as a dominant spoligotype (41.2% of the isolates) followed by SB0133 (14.7%). Comparison of spoligotypes with an M. bovis global database http://www.mbovis.org revealed six new spoligotypes which were subsequently registered in the database with international identification codes of SB1517, SB1518, SB1519, SB1520, SB1521 and SB1522. The majority of strains were obtained from cattle slaughtered at Addis Ababa abattoir. On the basis of the Spoligotype Evolutionary Index, SEI (a numeric expression approach to make standardized comparison of spoligotype evolution), M. bovis isolates from Ethiopia were relatively more heterogeneous (SEI = 3.2) compared to isolates from other countries. This might be attributed to extensive livestock movement linked to trading or seasonal migration, high degree of livestock mingling, and also diversities of the countrys agricultural and livestock ecosystems, in addition to lack of disease control measures that led to high infection prevalence. Multiple spoligotype infection was recorded in nine (50%) of infected carcasses and this may indicate the prevailing high degree of super infection.ConclusionsThis study provided molecular evidence for the widespread distribution of M. bovis in the cattle population in Ethiopia. It also demonstrated a relatively high degree of genetic polymorphism of the isolates. Further molecular investigation of M. bovis strains in humans and other domestic animals is recommended in order to elucidate the zoonotic importance as well as reservoirs and pattern of transmission among various hosts.

Factors associated with severity of bovine tuberculosis in Ethiopian cattle.

Bovine TB is a disease of high economic and public health importance particularly in resource poor countries. Many aspects of pathogenesis of bovine TB in cattle have not been well understood. We carried out an investigation on 337 Ethiopian cattle with characteristic TB-like lesions to describe severity of pathology and factors associated with it. Severity of pathology was determined based upon gross lesion characteristics, distribution and presence/absence of viable mycobacteria. Molecular speciation of mycobacteria was performed using Gene-Probe’s Accu-Probe method. Mycobacterium bovis was identified by genomic deletion analysis and spoligotyping. Data were analysed using descriptive statistics and regression model. The results showed that TB-like lesions and M. bovis were more frequently observed in lungs and respiratory lymph nodes. Mammary lesions yielded significant proportion of M. bovis upon culturing. Intestinal lesions were the second most frequently encountered pathology; upon culturing, however, the tissue specimens yielded the lowest proportion of M. bovis isolates. Sex, breed and management system were found to significantly affect TB manifestation. Female (β ± SE = 4.1 ± 1.0; P = 0.00) and exotic breed (β ± SE = 1.7 ± 0.9; P = 0.045) were at a relatively higher risk of developing severe tuberculosis. TB pathology was more severe in cattle raised under large-scale farming (β ± SE = 2.3 ± 0.5; P = 0.00). The fact that severe tuberculosis is linked to high degree of disease transmission potential warrants implementation of proper disease surveillance programs in large-scale farms. Isolation of M. bovis from mammary and muscle tissues implies a potential threat of zoonotic transmission, where raw milk and raw beef constitute a customary dietary regimen in Ethiopia.

Assessing the Key Attributes of Low Utilization of Mammography Screening and Breast-self Exam among African-American Women

PURPOSE: African-American (AA) women living in four Black Belt Counties (BBC) of Alabama; consisting of Barbour, Macon, Green and Wilcox are known to have lower mammogram utilization and breast self-exam rates when compared to their white female counterparts. The influence of socioeconomic and demographic factors on these disparities has not been clearly defined so far. Our study was designed to determine whether these observed disparities can be predicted with the socioeconomic and other demographic attributes. METHODS: Health Disparity Questionnaires data (n = 516) for BBC of Alabama was analyzed using a logistic regression model to examine the association of breast cancer screening rates and breast self-exam with income, the level of education, family doctor, type of health insurance, obesity, and age. RESULTS: Income, education, family doctor, age and health insurance were independent predictors for the low utilization rate of mammography and breast self-exam (BSE). CONCLUSION: Improving socioeconomic conditions such as level of education and availability of health care are essential to increase the rates of breast cancer screening test and breast self-exam in the BBC of Alabama.

Risk factors associated with prevalence of tuberculosis-like lesions and associated mycobacteria in cattle slaughtered at public and export abattoirs in Ethiopia

This study was aimed at investigating risk factors associated with prevalence of tuberculosis (TB)-like lesions and associated mycobacteria in Ethiopian cattle slaughtered. The study was carried out during 2006–2007 in five selected municipal and export abattoirs. Methods of investigation involved detailed necropsy examination of carcasses and isolation of mycobacteria from pathologic tissue specimens. Factors of animal and environment origin were recorded and examined as explanatory variables in relation to the presence or absence of TB-like lesions and the presence of viable mycobacteria. Multivariable logistic regression analysis was used to identify risk factors associated with prevalence of TB-like lesions and mycobacteria. Out of 3,322 carcasses inspected, 10.2% (95% confidence interval (CI) [9.2–11.3]) and 3.2% (95% CI [2.6–3.8]) were positive, respectively, based on necropsy and bacteriologic examinations. The highest and lowest lesion prevalence was recorded in Adama (24.7%) and Yabello (4.2%), respectively. Multivariable logistic regression analysis identified age, breed, abattoir location, geographic origin and management system as being risk factors for prevalence of TB-like lesions and occurrence of viable mycobacteria in Ethiopian cattle. The study demonstrated mycobacterial infection as important infectious disease of Ethiopian cattle. The reported confirmed cases of the disease in different management and geographic settings in Ethiopia disproved the earlier held opinion of its occurrence as a low sporadic profile. In view of a dietary proclivity of Ethiopian communities (milk and meat are predominantly consumed raw) and lifestyle (close contact of people with animals), the risk of bovine tuberculosis as a public health threat is eminent.

The Association between Interrelationships and Linkages of Knowledge about HIV/AIDS and its Related Risky Behaviors in People Living with HIV/AIDS

The relationship between knowledge about HIV/AIDS and its associated risky behaviors is complex and has not been sufficiently explored. It is especially important to look at some of the aspects of this relationship among people living with HIV/AIDS (PLWHA) in order to develop effective intervention strategies to reduce HIV/AIDS risky behaviors. The objective of this study was to investigate the association between knowledge about HIV/AIDS and its risky behaviors among PLWHA. Methods Risk taking behavior among the participants was measured as the number of all risky behaviors before and after the knowledge of their HIV/AIDS positive status. Knowledge was measured by the extent to which participants answered the HIV/AIDS related questions. The relationships between the identified HIV/AIDS risky behaviors and the knowledge among PLWHA were analyzed using Structural Equation Modelling. Results 341 questionnaires were administered and 326 (96%) were completed and returned from PLWHA clients of HIV/AIDS outreach facility in Alabama. Analysis revealed that, knowledge of HIV/AIDS, and knowledge of a properly used condom in preventing the infection through sexual activity were positively related with knowledge of where to get tested for HIV/AIDS. Using drugs before sex was significantly related with having sex with prostitutes (total effects’ standardized regression coefficient (TESRC)=0.29, p<0.001). Sharing the same syringe or needle with another person or other people to inject oneself was strongly related with number of sexual partners within one year (TESRC=0.25, p<0.001), and sex with injecting drug users (TESRC=0.45, p<0.001). Conclusion A deeper understanding of HIV/AIDS and some of its transmission pathways appears to be very effective in practicing the taking of preventive measures such as using condoms or getting tested for HIV. Increasing access to HIV/AIDS education could therefore be very useful in providing further gains in HIV/AIDS awareness among PLWHA.