Open Access Original Research Article

Molecular Epidemiology of Vibrio cholerae Recovered from Sewage Drains, Captured Fish and Humans in 2015/16 Cholera Outbreak in Zanzibar, Tanzania

A. R. Rabia, P. N. Wambura, G. Misinzo, S. I. Kimera, R. H. Mdegela, A. Mzula, F. A. Khamis

Journal of Advances in Microbiology, Page 1-11
DOI: 10.9734/JAMB/2017/36036

Aims: Zanzibar shares global burden of cholera epidemic suffering annual outbreaks with case fatality rates (CFR) of 1.8%. This study aimed at determining the transmission chain of the outbreak through marine fish by molecular characterization of Vibrio cholerae isolates.

Study Design: Cross sectional design was used to collect samples from fish, sewage sites and stool from clinical cases.

Place and Duration of Study: The study was carried out in Zanzibar municipality between November 2015 and May 2016.

Methodology: Epidemiological data on the outbreak was provided by the Ministry of Health and Social Affairs, Zanzibar. Sixty samples from fish intestines, 23 samples from sewage drains and 38 human stools were investigated. Vibrio cholerae was identified biochemically and serology was done using Polyvalent, Inaba, Ogawa and O139 antisera. Kirby-Bauer disc diffusion was used for antibiotic sensitivity against seven antibiotics. DNA was extracted and PCR performed using ctxB forward and reverse ctxB primers. Gene sequences were interpreted by Mega 7.0 software.

Results: Thirty stool samples (79%), 9 fish samples (15%) and 6 sewage samples (26%) were positive for Vibrio cholerae. All isolates were identified: serogroup O1, biotype El Tor and serotype Ogawa. Age category 16-30 yrs old had highest number of cases (37.6%). Case fatality rate (CFR) was 1.8%, more mortalities were in males and >5yrs old. None of the isolates was resistant to ciprofloxacin. High resistance was against nalidixic acid, erythromycin, co-trimaxozole, ampicillin and tetracycline. Multidrug resistance was observed in 40% of isolates. CtxB gene sequencing revealed that the current Vibrio cholerae strain was homologous to Haiti 2013-2015 and China 2016 strains, but distinct from Zanzibar 2013 strain.

Conclusion: Fish could be the source of Vibrio cholerae transmission in Zanzibar. Presence of rapidly emerging endemic reservoir of Vibrio cholerae in Zanzibar environment was suspected favouring horizontal gene transfer with resultant novel strains. High drug resistance and multidrug resistance are matters of public health concern.


Open Access Original Research Article

A New Spore Wall Protein 9 Gene Cloned from Nosema pernyi (Microsporidia) Isolated from Chinese Oak Silkworm, Antheraea pernyi

Yue- Yyue Ma, Piao Lei, Deyi Wang, Weihao Zhong, Yong Wang, Li Qin

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/JAMB/2017/36015

Aims: China has plenty of oak trees that form the cradle of tussah (Antheraea pernyi) industry. Pebrine is a serious disease along with tussah rearing and is difficult to solve. This pathogen named Nosema pernyi, which can infect the Chinese oak silkworm. The spores of N. pernyi have thick spore wall constructed by exospore and endospore. Spore wall proteins contact with host cells are related to microsporidia infection.

Methodology: In this study, we used the percoll gradient centrifugation method to purify spores of N. pernyi. Electron microscopy was used to detect the spore wall structure. Recombinant prokaryotic expression vector was constructed and induced in Escherichia coli. SDS-PAGE and Western blot (WB) was performed to detect the protein expression.

Results: A gene was cloned including an open reading frame (ORF) of 954 bp coding for a theoretical 317 amino acids protein. BLASTp showed a high amino acid sequence homology with spore wall protein in other microsporidia species. We named this gene NpSWP9, and a prokaryotic expression vector was constructed. Recombinant plasmid of NpSWP9-E1 Vector was transferred into Transetta (DE3). According to SDS-PAGE result, the molecular weight of the target protein was 38 kDa under the condition of IPTG (Isopropyl β-D-Thiogalactoside) for 5 h. According to the WB result, about 40 kDa band was detected by anti-HIS tag antibody.

Conclusion: A new spore wall protein gene was identified in N. pernyi from A. pernyi. This research provided a good basis for further studies on cellular localization and immunodetection of NpSWP9 in N. pernyi.


Open Access Original Research Article

Potency of Plant-based Fungicides against a Rot Pathogen of White Yam (Dioscorea rotundata Poir)

Markson, Aniedi-Abasi Akpan, Omosun, Garuba, Umana, Etim Johnson, Amadioha, Anderson Chidi, Udo, Samuel Effiong

Journal of Advances in Microbiology, Page 1-9
DOI: 10.9734/JAMB/2017/35718

Aims: This study assessed the in vitro antifungal potential of crude extracts of ten plants on the mycelial dry weight and spore germination of Botryodiplodia theobromae using hyphal extension bioassay.

Study Design: The experiment was a 10 x 2 x 6 factorial laid out in a Completely Randomized Design (CRD) and replicated three times. Means were separated using LSD (P<0.05).

Place and Duration of Study: Department of Botany, University of Calabar, Calabar and National Roots Crop Research Institute, Umudike both in Nigeria. The study was carried out between May 2015 and March, 2016.

Methodology: The plant materials of Afromomum melegueta, Zingiber officinale, Allium sativum, Cola attiensis, Ocimum gratissimum, Xylopia aethiopica, Piper guineense, Garcina cola, Monodora myristica and Senna occidentalis were extracted in water and ethanol. Infected yams were collected and packaged in sterile polythene bags and taken to the laboratory for isolation of microorganisms and isolates identified. The pathogenicity of the isolates used was confirmed using axenic cultures.

Results: Solvent of extraction and concentration of the extracts exerted significant influence on the performance of the extracts. Water extract treatments of Aframomum melegueta and Zingiber officinale were the best and comparable (P<0.05) in reducing spore germination each recording a value of 97%. The most impressive result obtained for ethanol extracted plant material was a 100% spore reduction value recorded for Z. officinale at 100 g/l concentration. Seeds of Aframomum melegueta and rhizomes of Zingiber officinale extracted in both water and ethanol were superior in reducing the mycelial biomass of B. theobromae compared to others. Water extracts of Aframomum melegueta and Zingiber officinale reduced the mycelial biomass of the test pathogen by 84.7% and 85.7% at 100 g/l concentration respectively. Their performances were comparable (P<0.05). Extracts of Allium sativum and Cola attiensis recorded the least spore germination reduction and mycelial dry weight reduction values irrespective of the solvent of extraction. No growth reduction was evident in the control treatments throughout the course of the study.

Conclusion: All the plant extracts tested inhibited the growth and development of B. theobromae to varying degrees. Solvent of extraction and concentrationof the extractsexerted significant influence on the performance of the extracts.


Open Access Original Research Article

Prevalence and Associated Pre-Disposing Factors of Amoebiasis among School Children in Makurdi Metropolis, Benue State, Nigeria

M. O. Iboyi, N. G. Imandeh, E. T. Azua

Journal of Advances in Microbiology, Page 1-6
DOI: 10.9734/JAMB/2017/36609

An epidemiological survey was conducted to determine the Prevalence and associated pre-disposing factors of amoebiasis among school children in Makurdi Metropolis, Benue state, Nigeria. Information on sex, age, location, source of drinking water, occupation of caregivers was retrieved through structured questionnaires. Three hundred and eighty five (385) stool samples were randomly collected and examined from children less than five years of age attending different Hospitals and Schools. Direct wet mount and Formol-ether concentration technique were adopted. Findings were subject to Chi-square analysis at P= 0.05. Findings revealed that a total of 8.31% children were infected with amoebiasis. Age related prevalence of infection showed the highest rate among children of 49-60 months (19.2%) and lowest among children of <12 months (1.5%; p<0.05). The males showed the highest prevalence (14.1%) than the females (8.46%) without a significant differences (p>0.05). Location related prevalence showed that the infection rate in Wadata was highest (18.4%), and the lowest prevalence was at High-Level (4.5%; p<0.05). Distribution of Entamoeba histolytica infection based on the major sources of drinking water showed that subjects who depended on tank reservoir as their major source of drinking water recorded the highest prevalence (18.8%), while those that drank packet water recorded no case of infection (p<0.05). Occupational prevalence showed that infection rate was highest among children whose caregivers were traders (13.5%), followed by farmers (9.6%), while civil servants showed the lowest prevalence of infection (9.0%; p>0.05). Increased health education, awareness creation, and provision of essential amenities for the children and their caregivers will go a long way in mitigating the present scenario.


Open Access Original Research Article

The Prevalence of Coagulase-Positive Staphylococci Colonization among Diabetic Patients with Foot Ulcers at Vihiga County Referral Hospital, Kenya

Tuvei Susan Mamusavu, Guyah Benard, Abong’o Benard

Journal of Advances in Microbiology, Page 1-8
DOI: 10.9734/JAMB/2017/32826

Aim: To investigate the prevalence of Coagulase-positive Staphylococci colonization among diabetic patients with foot ulcers at Vihiga County Referral Hospital, Kenya.

Study Design: This study employed a hospital based cross- sectional study design of diabetic patients with foot ulcers at Vihiga County Referral Hospital, Vihiga County, Kenya.

Place and Duration of Study: Vihiga County Referral Hospital, Kenya between February 2016 and April 2016.

Methodology: The study population comprised of 225 adult diabetic patients and a sample size of 156 patients with foot ulcers who attend Vihiga County Referral Hospital for treatment. Pus specimens from foot ulcers of diabetic patients were swabbed aseptically for Coagulase-positive Staphylococci screening. Gram staining was done to determine the organism present. Subsequently, the specimens were inoculated on to Blood Agar (BA) plates incubated at 37°C for 24 - 48 hours. Isolated colonies were further tested for the production of free coagulase enzyme using the tube coagulase test, based on standard methods. Coagulase-positive Staphylococci ATCC 25923, a known coagulase producer was included as a control strain.

Results: 94 out of 156 pus swabs were coagulase positive. This implied that the prevalence of Coagulase-positive staphylococci was 94(60.3%) among Diabetic patients with foot ulcers seeking treatment at Vihiga County Referral Hospital, Kenya. Socio demographics of participants indicated that majority of the participants were; male at (51.3%), over 60 years at (43.6%), married at (85.3%) and had up to primary education at (60.3%).

Conclusion: Diabetic patients with foot ulcers at Vihiga County Referral Hospital, Kenya are prone to Coagulase-positive staphylococci colonization.