Carriage of linezolid-resistant enterococci (LRE) among humans and animals in Nigeria: coexistence of the cfr, optrA, and poxtA genes in Enterococcus faecium of animal origin

Objectives: In contrast to increasing reports of the emergence of linezolid-resistant enterococci (LRE) emanating from many countries in Europe, Asia, and North America, data on its status and dissemination from the African continent remain scarce, with the information available limited to countries in North Africa. This study investigated the carriage of LRE and the genetic mechanism of resistance among Enterococcus faecium and Enterococcus faecalis strains recovered from humans and animals in Makurdi, Nigeria. Methods: We conducted a cross-sectional study between June 2020 and July 2021 during which 630 nonduplicate human and animal faecal samples were collected and processed for the recovery of LRE. The genetic mechanisms for resistance were investigated using polymerase chain reaction (PCR) and Sanger sequencing. Results: Linezolid-resistant enterococci were recovered from 5.87% (37/630; 95% CI: 4.17–8.00) of the samples, with the prevalence in animals and humans being 6.22% [(28/450); 95% CI: 4.17–8.87] and 5.00% [(9/180); 95% CI: 2.31–9.28], respectively. All isolates remained susceptible to vancomycin. No known point mutation mediating linezolid resistance was detected in the 23S rRNA and ribosomal protein genes; however, acquisition of one or more potentially transferable genes (cfr, optrA, and poxtA) was observed in 26 of the 37 LRE isolates. Co-existence of all three transferable genes in a single isolate was found in four E. faecium strains of animal origin. Conclusion: This study provides baseline evidence for the emergence and active circulation of LRE driven majorly by the acquisition of the optrA gene in Nigeria. To the best of our knowledge, our study is the first to report a co-carriage of all three transferable linezolid resistance determinants in E. faecium. Active LRE surveillance is urgently required to understand the extent of LRE spread across sub-Saharan Africa and to develop tailored mitigation strategies

Identification of Adult Fasciola spp. Using Matrix-Assisted Laser/Desorption Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry

Fascioliasis is a neglected trematode infection caused by Fasciola gigantica and Fasciola hepatica. Routine diagnosis of fascioliasis relies on macroscopic identification of adult worms in liver tissue of slaughtered animals, and microscopic detection of eggs in fecal samples of animals and humans. However, the diagnostic accuracy of morphological techniques and stool microscopy is low. Molecular diagnostics (e.g., polymerase chain reaction (PCR)) are more reliable, but these techniques are not routinely available in clinical microbiology laboratories. Matrix-assisted laser/desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is a widely-used technique for identification of bacteria and fungi; yet, standardized protocols and databases for parasite detection need to be developed. The purpose of this study was to develop and validate an in-house database for Fasciola species-specific identification. To achieve this goal, the posterior parts of seven adult F. gigantica and one adult F. hepatica were processed and subjected to MALDI-TOF MS to create main spectra profiles (MSPs). Repeatability and reproducibility tests were performed to develop the database. A principal component analysis revealed significant differences between the spectra of F. gigantica and F. hepatica. Subsequently, 78 Fasciola samples were analyzed by MALDI-TOF MS using the previously developed database, out of which 98.7% (n = 74) and 100% (n = 3) were correctly identified as F. gigantica and F. hepatica, respectively. Log score values ranged between 1.73 and 2.23, thus indicating a reliable identification. We conclude that MALDI-TOF MS can provide species-specific identification of medically relevant liver flukes

Evidence of Cryptococcosis in cattle in Zaria Kaduna state, Nigeria

Aim: Cryptococcosis is azoonotic infection caused by fungal of the Cryptococcus neoformans complex comprising of C. neoformans and C. gattii.The disease affects humans and animals worldwide causing morbidity and mortality. This work was carried out to determine the occurrence of cryptococcal antigens and factors associated with presence of antigens in cattle in Zaria, Nigeria. Materials and Methods: Three hundred and ninety (390) serum samples from cattle of various ages were collected from 11 farms in Zaria, Nigeria. The samples were analysed using alatex agglutination test and lateral flow assay kit which detectsthe polysaccharide capsular antigens of Cryptococcus species. Results:Out of the 390 samples tested 28 (7.17%) were found to be positive using the latex agglutination test while only of these 22 (5.64%) were positive using the lateral flow assay. There was a strong correlation (r=0.939, p=0.0002) between the results of the latex agglutination test and the lateral flow assay. There was no statistically significant difference (p>0.005) in positivity for cryptococcal antigens between sex, age and sex, though, there was a statistically significant difference (p<0.05) in positivity between management systems i.e. semi-intensive and intensive farming systems. Conclusions: The epidemiological value of this report lies in its demonstration that the risk of cattle and humans infection with cryptococcosis exist in farms in Zaria. The presence of this pathogen among these cattle poses an economic threat to the livestock industry due to the mastitis it causes. It also poses a significant public health threat because of its zoonotic nature and the increasing population of immunocompromised individuals. Large scale studies to determine specific risk factors and the role of the environment and experimental studies to determine what governs the transition from nasal colonisation to infection are recommended. [Vet World 2013; 6(2.000): 64-67

Serological prevalence of leptospirosis in cattle slaughtered in the Zango abattoir in Zaria, Kaduna State, Nigeria

Leptospirosis is an occupational zoonosis caused by pathogenic leptospires. In this study, the presence and prevalence of antibodies specific to Leptospira spp. serovar Hardjo in 142 cattle slaughtered between June and July 2011 was investigated using the enzyme-linked immunosorbent assay (ELISA). Five (3.50%) of the 142 cattle sampled were seropositive for antibodies to Leptospira spp. serovar Hardjo. Despite the fact that there was no significant difference (p>0.05) in seropositivity between sexes and between breeds sampled, there was a significant difference (p<0.05) in sero-positivity between the different age groups examined. Leptospirosis is present in cattle slaughtered in the Zango abattoir; butchers and abattoir workers are exposed to infected animals and are at risk of being infected by Leptospira spp. serovar Hardjo

Avian influenza (H5 subtype) antibodies in village chickens in four local government areas of Kaduna state, Nigeria

Aim: Biosecurity measures are rarely implemented in traditional farming systems especially in the villages. Given the importance of the village chickens as a source of income for rural families and its public health concern due to the frequent contact that exist between these birds and humans a study was conducted to assess the presence of antibodies to the H5 avian influenza virus subtype in village chickens in some Local Government Areas (LGAs) in Kaduna State. Materials and Methods: A total of 480 sera samples were obtained from apparently healthy local chickens in five LGAs where the avian influenza outbreak has not been reported. The sera were subjected to the Haemagglutination inhibition (HI) test using the H5N2 avian influenza antigen. Results: An overall prevalence of 2.9% with an individual seroprevalence of 10%, 0.8%, 4.1% and 3.3% in Jaba, Jemma'a, Kaura and Zango Kataf local government areas respectively. There was no association between presence of pigs and detection of avian influenza antibodies, p=0.8723, OR 0.9153 (95% CI: 0.3108&amp;#150;2.695), but there was an association between presence of water birds (Gesse and Ducks) and detection of avian influenza antibodies, p= 0.0203, OR 3.488 (95% CI: 1.146&amp;#150;10.61). Conclusions: This result highlights the important role apparently healthy village chickens may play in virus perpetuation (reservoir) and in the spread of avian influenza to other animals and humans. An enhanced and sustained virological surveillance for the virus in village chickens was recommended. [Vet World 2012; 5(12.000): 713-717

Carriage of linezolid-resistant enterococci (LRE) among humans and animals in Nigeria: coexistence of the cfr, optrA, and poxtA genes in Enterococcus faecium of animal origin

ABSTRACT: Objectives: In contrast to increasing reports of the emergence of linezolid-resistant enterococci (LRE) emanating from many countries in Europe, Asia, and North America, data on its status and dissemination from the African continent remain scarce, with the information available limited to countries in North Africa. This study investigated the carriage of LRE and the genetic mechanism of resistance among Enterococcus faecium and Enterococcus faecalis strains recovered from humans and animals in Makurdi, Nigeria. Methods: We conducted a cross-sectional study between June 2020 and July 2021 during which 630 non-duplicate human and animal faecal samples were collected and processed for the recovery of LRE. The genetic mechanisms for resistance were investigated using polymerase chain reaction (PCR) and Sanger sequencing. Results: Linezolid-resistant enterococci were recovered from 5.87% (37/630; 95% CI: 4.17–8.00) of the samples, with the prevalence in animals and humans being 6.22% [(28/450); 95% CI: 4.17–8.87] and 5.00% [(9/180); 95% CI: 2.31–9.28], respectively. All isolates remained susceptible to vancomycin. No known point mutation mediating linezolid resistance was detected in the 23S rRNA and ribosomal protein genes; however, acquisition of one or more potentially transferable genes (cfr, optrA, and poxtA) was observed in 26 of the 37 LRE isolates. Co-existence of all three transferable genes in a single isolate was found in four E. faecium strains of animal origin. Conclusion: This study provides baseline evidence for the emergence and active circulation of LRE driven majorly by the acquisition of the optrA gene in Nigeria. To the best of our knowledge, our study is the first to report a co-carriage of all three transferable linezolid resistance determinants in E. faecium. Active LRE surveillance is urgently required to understand the extent of LRE spread across sub-Saharan Africa and to develop tailored mitigation strategies

Serological detection of antibodies against Hepatitis E virus among Camels (Camelus dromedarius) in Nigeria

Hepatitis E virus (HEV) is a zoonotic disease with increasing endemicity in many countries around the world. At the moment no data on the status of and epidemiology of HEV in camels an important livestock in the semi-arid and arid parts of Nigeria. This study determined HEV seroprevalence in two areas (with high population of camel in Nigeria) using indirect Enzyme Linked Immunosorbent Assay. Out of 88 camels sampled, HEV antibodies were detected in 27 suggesting a prevalence rate of 30.7%. Higher rates were observed among camels in Maigatari LGA (22.7%) compared with 7.9% in Suletankarkar LGA, Jigawa State. These findings reinforce the need for further studies on molecular characterization and evolutionary diversity in Camel as well as pastoralists in Nigeria

Identification of Adult Fasciola spp. Using Matrix-Assisted Laser/Desorption Ionization Time-of-Flight (MALDI-TOF) Mass Spectrometry

Fascioliasis is a neglected trematode infection caused by Fasciola gigantica and Fasciola hepatica. Routine diagnosis of fascioliasis relies on macroscopic identification of adult worms in liver tissue of slaughtered animals, and microscopic detection of eggs in fecal samples of animals and humans. However, the diagnostic accuracy of morphological techniques and stool microscopy is low. Molecular diagnostics (e.g., polymerase chain reaction (PCR)) are more reliable, but these techniques are not routinely available in clinical microbiology laboratories. Matrix-assisted laser/desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is a widely-used technique for identification of bacteria and fungi; yet, standardized protocols and databases for parasite detection need to be developed. The purpose of this study was to develop and validate an in-house database for Fasciola species-specific identification. To achieve this goal, the posterior parts of seven adult F. gigantica and one adult F. hepatica were processed and subjected to MALDI-TOF MS to create main spectra profiles (MSPs). Repeatability and reproducibility tests were performed to develop the database. A principal component analysis revealed significant differences between the spectra of F. gigantica and F. hepatica. Subsequently, 78 Fasciola samples were analyzed by MALDI-TOF MS using the previously developed database, out of which 98.7% (n = 74) and 100% (n = 3) were correctly identified as F. gigantica and F. hepatica, respectively. Log score values ranged between 1.73 and 2.23, thus indicating a reliable identification. We conclude that MALDI-TOF MS can provide species-specific identification of medically relevant liver flukes