Prevalence and antimicrobial resistance pattern of coagulase negative Staphylococci isolated from pigs and in-contact humans in Jos Metropolis, Nigeria

The nasal carriage and antibiotic susceptibility pattern of coagulase negative  staphylococci (CoNS) isolates from healthy pigs and in-contact humans were  investigated in 300 pigs and 101 in-contact humans from pig farms and abattoir. The results indicate that 13.2% (53/401) of the isolates were CoNS species based on confirmatory test with Microgen biochemical kit and were further subjected to antibiotic susceptibility testing. Nine CoNS species were identified; S. haemolyticus (n = 10), S. simulans (n =5), S. chromogen (n = 9), S. warneri (n =5), S. xylosus (12), S. epidermidis (n = 5), S. schleiferi (n = 5) and S. hominis (n = 2). Overall, resistance to beta-lactams was the most observed; 79.2% of the isolates were resistant to penicillin while 11.3% and 7.5% were respectively resistant to oxacillin and cefoxitin, respectively.  Resistance to 2 or more antimicrobial agents was observed in 39.6% (21/53) of the CoNS isolates. All the isolates were resistant to at least one antimicrobial agent except for gentamicin. Multidrug resistant CoNS are common colonizers of apparently healthy pigs and in-contact humans in the study area with S. xylosus and S. haemolyticus being the major species detected.Key words: Antibiotics, CoNS, pigs, humans

Farmers’ knowledge on forage production in smallholder dairy systems of Uganda

The aim of the study was to assess dairy farmers’ knowledge on forage production and utilization in the Lake Victoria crescent and Eastern Highlands Agro Ecological Zones (AEZs) of Uganda. Semi-structured questionnaires were administered to a total of 208 small holder dairy farmers in Masaka (100) and Mbale (108) districts. Data was analyzed using Statistical Package for Social Scientists. While the main source of forage is on farm (67.2%), forage growing is not taken as a tradition among small holder dairy farmers. The most prominent forage species used for feeding livestock are Pennisetum purpureum, Calliandra calothyrsus, Musa paradisiacal (peelings and stems), and Leucaena leucocephala. Milk production increases during months of forage abundance (March to May and September to November) and the observed trends are generally comparable to the seasonal rainfall patterns in Uganda. Forage production among dairy farmers is significantly (P < 0.05) influenced by location, household size, land ownership, forage source and livestock feeding system. Apart from chopping before feeding the animals, minimal processing is done to forage. The study provides a basis for designing interventions for improving fodder production and utilization among Uganda’s smallholder dairy farmers.Buyinza Joel, Sekatuba Jude, Ongodia Gerald, Eryau Kenneth, Nansereko Susan, Opolot Ibwala Vincent, Kwaga Phiona, Akellem Richard, Mudondo Scovia and Agaba Hillar

Diversity and antimicrobial resistance of Salmonella enterica isolated from fresh produce and environmental samples

In Nigeria, as in most developing countries, vegetable farmers depend largely on wastewater for irrigation and on untreated manure for soil enrichment. Salmonella is among the most important foodborne pathogens worldwide with fresh vegetables as major route of transmission to man. A total of 440 samples comprising vegetables and environmental samples (irrigation water and manure treated soil) were analyzed for the presence of Salmonella, resistance and virulence genes and diversity of isolates by genotyping. Samples were obtained from five irrigation fields in Kano and Plateau States and cultured using selective isolation with prior enrichment method. Presumptive isolates were identified and characterized using conventional biochemical methods and Microbact 24E (Oxoid, UK) identification kit. Amplification of virulence (invasive A and enterotoxin) genes by polymerase chain reaction (PCR) further confirmed Salmonella and its virulence potential. Enterobacterial repetitive intergenic concensus (ERIC) fingerprinting PCR showed genetic diversity of confirmed isolates. Confirmed isolates were evaluated for susceptibilities to eight commonly used antimicrobial agents. Sixty-one (13.9%) samples were positive for Salmonella. The distribution of serotypes included; Salmonella typhi (7.7%), Salmonella paratyphi (2.0%) and Salmonella typhimurium (4.1%). S. typhi had the highest isolation rate and was most commonly detected in vegetables. Simultaneous resistance to all antibiotics assayed was found amongst the salmonellae. Fingerprinting pattern of the Salmonella strains from the different samples showed marked similarities and close genetic relatedness. Cluster analysis at a coefficient of similarity of 0.82 grouped the fifteen strains of Salmonella assayed into five different groups. Our results indicate that irrigated vegetables are vehicles of transmission of potentially pathogenic Salmonella isolates that can contribute to the development of salmonellosis and other Salmonella related infections in Nigeria. This study provides data that support the potential transmission strains of Salmonella harboring virulence and resistance factors from vegetables and environmental sources to cause infections in humans

Electropherotypes and Subgroups of Group A Rotaviruses Circulating among Diarrhoeic Children in Kano, Nigeria

Background: It is estimated that about 600\u2009000 children die annually as a result of severe dehydrating diarrhea caused by rotaviruses. The virus is a double stranded RNA (dsRNA) virus with 11 segments. Group A rotaviruses show a characteristic 4-2-3-2 pattern following electrophoresis. The VP6 subgroups, I and II exist. This work was carried out to study the prevalence of rotavirus infection among children 0-5 years with diarrhea in Kano, and to determine the circulating subgroups and electropherotypes and of the rotavirus isolates. Methods: Two hundred and eighteen stool specimens from children 0-60 months (198 diarrheic and 20 non-diarrheic) were collected from different hospitals and health care centers in Kano and subjected to group A rotavirus enzyme linked immunosorbent assay (ELISA) to determine presence of group A rotavirus, subgroup ELISA to determine the VP6 subgroups and polyacrylamide gel electrophoresis (PAGE) to determine the electropherotypes present. Results: The long electropherotypes (47.05%) of four variations dominated over the short electropherotype (17.64%). About 11.76% of the isolates were of mixed infection. Dominance of subgroup II (45%) over subgroup I (25%), and the presence of both subgroups I and II (10%) and neither subgroup I nor II (15%) was observed in this study. Conclusion: Information on the genomic diversity of the RNA electropherotypes in this region, Kano, is reported in this study.Fond: On l'estime qu'environ 600.000 enfants meurent annuellement en raison de la diarrh\ue9e de d\ue9shydratation grave provoqu\ue9e par des rotaviruses. Le virus est un virus bicat\ue9naire d'ARN (dsRNA) avec 11 segments. Groupez l'exposition de rotaviruses d'A un mod\ue8le 4-2-3-2 caract\ue9ristique apr\ue8s l'\ue9lectrophor\ue8se. Les sous-groupes VP6, l'I et l'II existent. Ces travaux ont \ue9t\ue9 men\ue9s \ue0 bien pour \ue9tudier la pr\ue9dominance de l'infection de rotavirus parmi des enfants 0-5 ans avec la diarrh\ue9e dans Kano, et pour d\ue9terminer les sous-groupes et les electropherotypes de circulation et des isolats de rotavirus. M\ue9thodes: Deux cents et dix-huit sp\ue9cimens de selles des enfants 0-60 mois (198 diarrhoeic et 20 non-diarrhoeic) ont \ue9t\ue9 rassembl\ue9s de diff\ue9rents h\uf4pitaux et centres de sant\ue9 dans Kano et soumis au groupe que l'enzyme de rotavirus d'A a li\ue9 l'analyse d'immunosorbant (ELISA) pour d\ue9terminer la pr\ue9sence du rotavirus du groupe A, ELISA de sous-groupe pour d\ue9terminer les sous-groupes VP6 et l'\ue9lectrophor\ue8se de gel de polyacrylamide (PAGE) pour d\ue9terminer les electropherotypes actuels. R\ue9sultats: Les longs electropherotypes (47.05%) de quatre variations ont domin\ue9 sur l'electropherotype court (17.64%). Environ 11.76% des isolats \ue9taient de l'infection m\ue9lang\ue9e. On n'a observ\ue9 la dominance du sous-groupe d'exc\ue9dent du sous-groupe II (45%) I (25%), et la pr\ue9sence des deux sous-groupes I et II (10%) et ni sous-groupe I ni II (15%) dans cette \ue9tude. Conclusion: L'information sur la diversit\ue9 genomic des electropherotypes d'ARN dans cette r\ue9gion, Kano, est rapport\ue9e dans cette \ue9tude

Prevalence and distribution of dermatophytosis lesions on cattle in Plateau State, Nigeria

Background and Aim: Dermatophytosis is an infection of the superficial, keratinized structures of the skin, nails, and hair of man and animals caused by a group of fungi called dermatophytes in the genera Trichophyton, Microsporum, and Epidermophyton. The prevalence of dermatophytosis among cattle in Nigeria and Plateau State, in particular, is yet to be fully determined. This study aimed to determine the prevalence and the distribution of dermatophytosis lesions on cattle in Plateau State, Nigeria. Materials and Methods: Four hundred and thirty-seven cattle showing visible skin lesions suggestive of dermatophytosis were drawn from nine local government areas (three each) from the three senatorial districts of Plateau State, Nigeria. Skin scrapings were aseptically collected using a cross-sectional study, in which sampling units were selected using purposive sampling method. Samples were processed for both direct microscopic examination and isolation of dermatophytes in culture. The isolates were stained with lactophenol cotton blue and identified microscopically based on the size, shape, and arrangement of macro- and micro-conidia. The dermatophytes were further identified by determining the sequences of the internal transcribed spacer regions of their ribosomal DNA. Data were analyzed and presented as percentages, bar graph, and Chi-square test of association. p≤0.05 was considered statistically significant. Results: The overall prevalence rate of bovine dermatophytosis in Plateau State was found to be 11.0%. Trichophyton verrucosum was more frequently isolated (54.2%) than Trichophyton mentagrophytes (45.8%). Age, breed, management practice, and season were significantly associated with the occurrence of the disease (p<0.05). Conclusion: Dermatophytosis among cattle may be of public health significance in Plateau State, Nigeria. This is the first report on the prevalence and distribution of dermatophytosis lesions on cattle from Plateau State, Nigeria

A carAB mutant of avian pathogenic Escherichia coli serogroup O2 is attenuated and effective as a live oral vaccine against colibacillosis in turkeys.

Colibacillosis is a serious and economically important disease of the respiratory tract of chickens and turkeys. The serogroups of Escherichia coli commonly associated with colibacillosis in poultry are O1, O2, and O78. Although previous attempts to develop a vaccine have not been very successful, vaccination is still considered the most effective way of controlling the disease. Therefore, our laboratory has been involved in the development of an attenuated live vaccine that will be effective in the prevention of colibacillosis. The carAB operon coding for carbamoyl-phosphate synthetase, an essential enzyme in arginine and pyrimidine metabolism, was selected for study. Generalized transduction was used to transfer a Tn10-generated mutation from a laboratory strain to virulent avian field isolates of E. coli. Molecular techniques were used to determine the point of Tn10 insertion within the carAB operon. The insertion mutants were then cured of the tetracycline resistance gene of the transposon to select for antibiotic-sensitive and stable carAB mutants. The degree of attenuation obtained by the mutation was determined in day-old chickens. Typically, when 100-fold the 50% lethal dose (for the wild type) was given, no more than 50% mortality in the day-old chickens was observed. The deletion mutant of serotype O2 was also found to be avirulent in turkeys rendered susceptible to infection with hemorrhagic enteritis virus A. Turkey poults vaccinated orally at 4 weeks old with either the wild-type E. coli EC317 strain or its carAB mutant EC751 were completely protected from infection following challenge with the homologous wild-type strain. Our data indicate that carAB mutants of virulent avian strains of E. coli will be effective and safe as live oral vaccines for prevention of colibacillosis in poultry

Molecular Characterization and Phylogenetic Analysis of Listeria monocytogenes Isolated from Milk and Milk Products in Kaduna, Nigeria

In this study, Listeria (L.) monocytogenes isolated from milk and milk products in Kaduna, Nigeria, were subjected to a multiplex PCR assay to identify virulence-associated genes (such as prf A, inl A, hly A, act A, and iap). Of the 36 isolates, 9 (25%) were positive for one or two virulence-associated genes. Based on the sample type, 6 (16.9%) of the isolates that possessed virulence-associated genes were obtained from raw milk, 2 (3.2%) from “Manshanu,” and 1 (2.8%) from “Kindrimo.” Sequence and phylogenetic analysis based on the 16S rRNA revealed that Nigerian L. monocytogenes isolates (NGA 34A, NGA 35A, NGA 41A, and NGA 38A), when compared with reference L. monocytogenes, were grouped into two distinct clusters, A and B, with sequence (NGA 34A, NGA 35A, and NGA 41A) phylogenetically closer to J1776; N1-011A; R2-502; J1816; and J2-031, whereas L. monocytogenes isolate (NGA 38A) clustered with EDG; J1-220; J1926; J1817; and J2-1091. The separation of the Nigerian L. monocytogenes isolates into linage A (responsible for epidemic listeriosis) and lineage B (responsible for sporadic cases of listeriosis) is of public health concern and that local isolates might have potentials for human food borne listeriosis based on the virulence factors so far identified