Mycobacterium bovis and M. tuberculosis in Goats, Nigeria

No abstract available

Direct detection of Mycobacterium tuberculosis with nitrate reductase assay and microscopic observation drug susceptibility

The global increase in tuberculosis drug resistant which is a threat to its control, require low cost method of diagnosis and detection. Available conventional and molecular methods consume time, and are expensive for countries with high disease burden. Nitrate Reductase Assay (NRA) and Microscopic Observation Drug Susceptibility (MODS) performance to directly detect tuberculosis resistance to four drugs was evaluated. The NRA (liquid and solid) and MODS performance of smear-positive sputum samples were evaluated; Sensitivities and specificities were compared with Proportion Method (PM). Sensitivity and specificity of liquid NRA (LNRA) were 90% and 98% (rifampicin), 81.8% and 100% (isoniazid), 88.9% and 98.1% (streptomycin), and 57.1% and 94.4% (ethambuthol). Also, the sensitivity and specificity for solid NRA (SNRA) were 69.2% and 98.3% (rifampicin); 100% and 100% (isoniazid); 88.9% and 95.2% (streptomycin); 70% and 80.6% (ethambuthol). Moreover, For MODS, rifampicin and isoniazid sensitivity and specificity was 100%, it was 100% and 98.1% for streptomycin, and 71.4% and 98.2% for ethambuthol. At day 14, the results available for LNRA, SNRA and MODS were 93%, 68.5% and 100% respectively. The agreement between LNRA and PM was 97% (RIF, INH and SM) and 90% (EMB). For SNRA, it was 93% (RIF), 100% (INH), 94% (SM) and 89% (EMB). While for MODS, it was 100% (RIF and INH), 98% (SM) and 95% (EMB). Direct NRA and MODS are sensitive, reliable and fast for antituberculosis drug susceptibility; they have potential to effectively and reliably detect drug resistant tuberculosis in the low resource countries. DOI: http://dx.doi.org/10.5281/zenodo.429588

Patterns of drug resistance in Mycobacterium tuberculosis from tuberculosis patients in Ibadan Nigeria

The success of the global tuberculosis (TB) control program has been threatened with drug resistant strains emergence; especially the Multidrug Resistant Tuberculosis (MDR-TB). Despite that Nigeria is one of the countries with high tuberculosis burden, little is known on the magnitude of MDR-TB in the country. This study was to determine drug resistant patterns of Mycobacterium tuberculosis isolated from patients that attended Directly Observed Treatment Short-course (DOTS) centres in Ibadan, Nigeria. Sputum samples collected from confirmed TB patients were processed using the N-acetyl L-cysteine-sodium hydroxide decontamination method. Direct drug susceptibility test was carried out against rifampicin, isoniazid, ethambuthol and streptomycin. Out of the 319 samples collected, 149 (46.7%) were culture positive and susceptibility test was completed for 101 (67.8%) isolates, out of which any resistance and mono-resistance to rifampicin was 23.8% and 8.9% respectively. In all 11.9% MDR-TB was observed comprising 30.8% (acquired), and 8.3% (primary) while, 3.96% showed resistance to all tested drugs. The patterns of MDR-TB in this study indicates that active case findings as well as expansion of drug susceptibility testing is required to effectively control TB, drug resistant strains and to forestall the transmission and spread of the drug-resistant TB in the society. DOI: http://dx.doi.org/10.5281/zenodo.428850

Isolation of Mycobacterium tuberculosis from livestock workers and implications for zooanthroponotic transmission in Ibadan, South-western Nigeria

Introduction: Tuberculosis (TB) remains a public health problem in sub-Saharan Africa coupled with dearth of information about the disease among livestock workers at risk of infection. We determined the prevalence of pulmonary TB infection and risk factors associated with its occurrence among livestock workers in south-western Nigeria. Methods:  A cross-sectional study was conducted using active case-finding among livestock workers with sub-clinical pulmonary TB between August, 2014 and March, 2015. Sputum samples were cultured and subjected to a two-step multiplex-PCR technique based on genus-typing and genomic regions-of-difference. Interviewer-administered questionnaire was utilized in assessing worker’s TB related knowledge, attitude and practices. Data were analysed using STATA 12.Results: Overall, 206 livestock workers (traders =136; butchers = 70) were screened; 5.1% (7/136) of the traders and 7.1% (5/70) of the butchers had positive mycobacterial cultures. Molecular techniques identified one Mycobacterium tuberculosis with six non-tuberculous mycobacteria (NTM) from the traders and four M. tuberculosis with one NTM from the butchers.Participants within the age range of 50 years and above were at higher risk of being infected with TB (OR=7.7; 95%CI:1.7–35.6).Conclusion: We confirmed M. tuberculosis as the cause of pulmonary TB among the livestock workers, with implications for zooanthroponotic transmission of the disease along the human-animal ecosystem interface in Nigeria

SEROLOGICAL SURVEY OF TOXOPLASMOSIS, NEOSPOROSIS AND BRUCELLOSIS AMONG CATTLE HERDS IN OYO STATE, SOUTH-WESTERN NIGERIA

Background: Several zoonotic diseases are known to constitute great impediment to livestock management and production worldwide, especially in developing countries where control measures are largely non-existent. This study sets out to investigate the occurrence of toxoplasmosis, neosporosis and brucellosis among cattle herds in Oyo State, southwest Nigeria. Materials and Methods: A cross-sectional survey to screen for antibodies to Toxoplasma gondii, Neospora caninum and Brucella abortus was conducted among 174 cattle in 17 herds. Sera obtained from the cattle were screened for antibodies to Toxoplasma gondii and Neospora caninum using enzyme-linked immunosorbent assay (ELISA) and for Brucella abortus antibodies using Rose Bengal test and Competitive Enzyme Linked Immunosorbent Assay (cELISA). Results: Overall, herd level prevalence of 52.9%, 23.5% and 23.5% as well as individual prevalence of 7.5%, 3.4% and 3.4% was obtained for toxoplasmosis, neosporosis and brucellosis, respectively. Antibodies to T. gondii, N. caninum and B. abortus were detected in 2 of the 17 herds, T. gondii and N. caninum in 4 herds, and T. gondii and B. abortus in 4 herds. Statistically significant association was only found between seropositivity to T. gondii antibodies and sex (

Exposure of Dentists to Mycobacterium tuberculosis, Ibadan, Nigeria

To determine the prevalence of Mycobacterium tuberculosis infection among dental patients and to assess dentists’ risk for exposure, we conducted a study among dental patients at a large tertiary hospital in Nigeria, a country where tuberculosis is endemic. Ten (13%) of 78 sputum samples obtained were positive for M. tuberculosis

Genetic profiling of Mycobacterium bovis strains from slaughtered cattle in Eritrea

<div><p><i>Mycobacterium bovis</i> (<i>M</i>.<i>bovis</i>) is the main causative agent for bovine tuberculosis (BTB) and can also be the cause of zoonotic tuberculosis in humans. In view of its zoonotic nature, slaughterhouse surveillance, potentially resulting in total or partial condemnation of the carcasses and organs, is conducted routinely. Spoligotyping, VNTR profiling, and whole genome sequencing (WGS) of <i>M</i>. <i>bovis</i> isolated from tissues with tuberculosis-like lesions collected from 14 cattle at Eritrea’s largest slaughterhouse in the capital Asmara, were conducted.The 14 <i>M</i>. <i>bovis</i> isolates were classified into three different spoligotype patterns (SB0120, SB0134 and SB0948) and six VNTR profiles. WGS results matched those of the conventional genotyping methods and further discriminated the six VNTR profiles into 14 strains. Furthermore, phylogenetic analysis of the <i>M</i>. <i>bovis</i> isolates suggests two independent introductions of BTB into Eritrea possibly evolving from a common ancestral strain in Europe.This molecular study revealed the most important strains of <i>M</i>. <i>bovis</i> in Eritrea and their (dis)similarities with the strains generally present in East Africa and Europe, as well as potential routes of introduction of <i>M</i>. <i>bovis</i>. Though the sample size is small, the current study provides important information as well as platform for future in-depth molecular studies on isolates from both the dairy and the traditional livestock sectors in Eritrea and the region. This study provides information onthe origin of some of the <i>M</i>. <i>bovis</i> strains in Eritrea, its genetic diversity, evolution and patterns of spread between dairy herds. Such information is essential in the development and implementation of future BTB control strategy for Eritrea.</p></div

Diagnostic performance of GeneXpert and Ziehl-Neelson microscopy in the detection of tuberculosis in Benue State, Nigeria

Background: Accurate and timely diagnosis of tuberculosis (TB) is key to effective treatment and management. This study was designed to compare the diagnostic performance of GeneXpert and Ziehl-Neelson (ZN) microscopy test using culture as the reference.Methods: Cross-sectional study was conducted in a tertiary hospital to compare the performance of GeneXpert and ZN test among HIV and non-HIV patients. Sputum samples were collected from 261 suspected TB patients and analyzed in the laboratory using GeneXpert, ZN test and culture. Statistical analysis included calculation of sensitivity, specificity, positive predictive value and negative predictive value. X2 was used to compare the outcome of diagnostic test and demographic variables. p-value &lt; 0.05 was considered significant.Results: Comparison of TB prevalence among urban versus rural areas using the three diagnostic tests are: ZN test: 32 (12.3%) vs 16 (6.1%; X2 7.63, P = 0.007); GeneXpert: 63 (16.1%) vs 20 (7.7%, X2 9.01, P = 0.003) and culture: 22 (8.4%) vs 10 (3.8% X2 4.44, P = 0.05). Also, prevalence of TB was significantly (P &lt; 0.05) higher among HIV negative 25 (9.6%) than HIV positive 23 (8.8%) patients. The overall prevalence of rifampicin resistance was 12 (4.60%). Out of 261 sputum samples examined for TB, 48 (18.38%) tested positive by ZN test, 62 (23.76%) by GeneXpert and 32 (12.26%) by culture. Two out of 32 samples that tested positive by culture were negative by GeneXpert. GeneXpert had higher sensitivity (93.75%) than ZN test (50.00%). However, they had equal specificity (86.03%). The sensitivity and specificity of ZN and GeneXpert among HIV patients was 58.33% (95% CI = 29.66–84.83) and 79.31% (95% CI; 69.24–87.26) and 91.67% (95% CI 61.51–99.79) and 80.67 (95% CI; 70.58–88.17) while among HIV negative patients; ZN test and GeneXpert assay had 45.00% (23.05–68.45) and 90.14% (84.04–94.50) and 95.00% (75.13–99.87) and 89.44% (83.13–93.96), respectively.Conclusion: GeneXpert demonstrated higher level of performance than ZN microscopy. We recommend the use of GeneXpert for diagnosis of TB in Benue State and Nigeria in general for effective treatment and management of tuberculosis.Keywords: Diagnostic performance, GeneXpert MTB/Rif, Ziehl-Neelson, Tuberculosis, HI

Genetic diversity of Mycobacterium tuberculosis complex strains isolated from livestock workers and cattle in Nigeria

CITATION: Adesokan, H. K. et al. 2019. Genetic diversity of Mycobacterium tuberculosis complex strains isolated from livestock workers and cattle in Nigeria. PLoS ONE, 14(2):e0211637, doi:10.1371/journal.pone.0211637.The original publication is available at https://journals.plos.org/plosoneENGLISH ABSTRACT: Molecular typing techniques are useful in understanding tuberculosis epidemiology; yet, they have been under-utilised at the human-animal interface in Nigeria. Sixty-four Mycobacterium tuberculosis complex (MTBC) isolates including 42 M. tuberculosis, 13 M. bovis and nine M. africanum obtained from livestock workers (LW, n = 47) and their cattle (n = 17) in three geographical zones of Nigeria were genotyped to identify and evaluate the genetic diversity of the circulating MTBC using spoligotyping. Distribution into clades of M. tuberculosis revealed; 45.3% Uganda I- [SIT46- cattle: 1; LW: 28], 14.1% Latin American Mediterranean- [SIT61, cattle: 1; LW: 8], and 1.6% T- [SIT53—LW: 1]. The M. bovis strains were 6.3% SB0944 [cattle: 4] and 1.6% each of SB0300, SB1026, SB1027 and SB1439 [cattle: 4]. Seventeen MTBC isolates [cattle: 7; LW: 10] yielded 14 new spoligotype patterns including three M. tuberculosis strains (three isolates), five M. bovis strains (five isolates) and six M. africanum strains (nine isolates), two of which belonged to MAF1. Only few families namely, the not previously described Uganda I-, LAM and SB0944 are predominant among the LW and cattle, with other types in lower prevalences. The strain population structure indicates an intriguing diversity and possible zoonotic linkage with consequences for TB control in the country. The need to employ newer molecular techniques such as Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeats and whole genome sequence to decipher circulating MTBC strains in Nigeria is advocated.Tertiary Education Trust Fund (TETFund, 2015) under the Staff Training and Development (ST&D) Scheme of the University of Ibadan, Nigeria.Publisher's versio