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ABSTRACT: Diarrhoea is a hallmark of HIV infections in developing countries, and many diarrhoea-causing agents are often transmitted through water. The objective of the study was to determine the diversity and antibiotic susceptibility profiles of bacterial organisms isolated from samples of household drinking-water consumed by HIV-infected and AIDS patients. In the present study, household water stored for use by HIV-positive patients was tested for microbial quality, and isolated bacterial organisms were analyzed for their susceptibility profiles against 25 different antibiotics. The microbial quality of water was generally poor, and about 58% of water samples (n = 270) were contaminated with faecal coliforms, with counts varying from 2 colony-forming unit (CFU)/100 mL to 2.4 x 10(4) CFU/100 mL. Values of total coliform counts ranged from 17 CFU/100 mL to 7.9 x 10(5)/100 mL. In total, 37 different bacterial species were isolated, and the major isolates included Acinetobacter lwoffii (7.5%), Enterobacter cloacae (7.5%), Shigella spp. (14.2%), Yersinia enterocolitica (6.7%), and Pseudomonas spp. (16.3%). No Vibrio cholerae could be isolated; however, V. fluvialis was isolated from three water samples. The isolated organisms were highly resistant to cefazolin (83.5%), cefoxitin (69.2%), ampicillin (66.4%), and cefuroxime (66.2%). Intermediate resistance was observed against gentamicin (10.6%), cefepime (13.4%), ceftriaxone (27.6%), and cefotaxime (29.9%). Levofloxacin (0.7%), ceftazidime (2.2%), meropenem (3%), and ciprofloxacin (3.7%) were the most active antibiotics against all the microorganisms, with all recording less than 5% resistance. Multiple drug resistance was very common, and 78% of the organisms were resistant to three or more antibiotics. Education on treatment of household water is advised for HIV-positive patients, and measures should be taken to improve point-of-use water treatment as immunosuppressed individuals would be more susceptible to opportunistic infections.
Journal of Health Population and Nutrition 09/2012; 30(3):241-9. · 0.95 Impact Factor
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ABSTRACT: We investigated the prevalence, haemolytic activities and antibiotic susceptibility profiles of Campylobacter species isolated from pigs in three farms in the Venda region, Limpopo province, South Africa. During the period of investigation, which spanned over one year, 450 faeces samples from pigs comprising 150 each from the three farms were collected and appropriately transported to the base laboratory at the Department of Microbiology, University of Venda for analysis. In total, the prevalence rate of Campylobacter isolates from all three farms was 30.2%, whereas, the rates of 25 -26% were recorded for farms X, Y and Z, respectively. Out of the isolated Campylobacter species 10 (12.5%) were identified as Campylobacter jejuni and 70(87.5%) as Campylobacter coli. Of the Campylobacter isolates from the farms, 23, 22 and 35 were -haemolytic from farms X, Y and Z, respectively. Susceptibility of the isolates to 12 antibiotics was determined by disc diffusion technique. The overall rate of resistance determined in this study to most of the antibiotics was 84.2%. Most Campylobacter isolates from farm X (< 50%) were resistant to ciprofloxacin, cefexime, and erythromycin, while > 50% were resistant to tetracycline, (54.5%) to vancomycin, (100%) to ampicillin and methicillin. The rates of resistance to these antibiotics were not significantly different from farms X and Y (p < 0.005). However, most isolates from farm Y were more resistant to ciprofloxacin (57.1%) than isolates from farm X (36.4%) and Z (40.7%). Resistance rates to tetracycline by C. coli isolated from farm Y (48%), farm Z (45.5%) and farm X (44.4%) were noted. Similar trend was observed for C. coli from farm Y (40%), farm Z (31.8%) and farm X (22.2%) for ciprofloxacin. All C. coli from farm Z showed higher level of resistance to ampicillin (100%), Y (64%) and X (55.6%). The C. jejuni isolates though few were markedly resistant to fluoroquinolone and the macrolide as well as aminoglycoside antibiotics. Most of the isolates were resistant to at least seven (7) of the antibiotics tested. These observations indicate high levels of resistance to antibiotics commonly used in the swine industry (erythromycin and tetracycline) among the C. coli and C. jejuni isolates from pigs. Erythromycin and ciprofloxacin are drugs for treatment of human campylobacteriosis. The high prevalence rate of resistance to these drugs among C. coli and C. jejuni isolates from pig faeces is of public health significance.
AFRICAN JOURNAL OF BIOTECHNOLOGY 02/2011; 10:703-711. · 0.57 Impact Factor
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ABSTRACT: Helicobacter pylori is the most important risk factor in gastritis, peptic ulcer and gastric cancer. This study explored the antimicrobial activity of the stem bark of Peltophorum africanum on H. pylori isolated in South Africa. Strains were isolated from patients presenting with gastric related morbidities at the Livingston Hospital, Port Elizabeth for endoscopy. Five extracts of P. africanum and clarithromycin were tested for the zone diameters of inhibition against 31 clinical strains of H. pylori, followed by the minimum inhibitory concentration (MIC) using metronidazole and amoxicillin as control antibiotics; and thereafter the rate of kill. Zone diameters of inhibition which ranged from 0 -23 mm were observed for all the five extracts and 0 -35 mm for clarithromycin. Marked susceptibility of strains (100%) was recorded for the ethyl acetate extract (P < 0.05). The MIC 50 ranged from 0.0048 -0.313 mg/mL and MIC 90 from 0.156 -0.625 mg/mL for the ethyl acetate extract (P. africanum EA). There was a significant statistical difference observed in potency with P. africanum EA compared to metronidazole and amoxicillin (P < 0.05) at MIC 90 . Complete killing of strain PE466C by P. africanum EA was observed at 0.05 mg/mL (½ x MIC) in 66 and 72 h and 0.2 mg/mL (2 x MIC) in 72 h. For strain PE252C, total killing was observed at 0.2 mg/mL (2 x MIC) in 66 h and at 0.05 mg/mL (½ x MIC), 0.1 mg/mL (MIC), 0.2 mg/mL (2 x MIC) and 0.4 mg/mL (4 x MIC) in 72 h, respectively. Our findings demonstrate the in vitro activity of the crude extracts of P. africanum and therefore provide evidence to justify the use of this plant in traditional medicine.
Crude ethyl acetate extract of the stem bark of Peltophorum africanum (Sond, Fabaceae) possessing in vitro inhibitory and bactericidal activity against clinical isolates of Helicobacter pylori. 08/2010; 4:1432-1440.
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ABSTRACT: Multidrug-resistant tuberculosis (MDR-TB) has been a cause of concern in both developed and developing countries. The prevalence of drug resistance in Mycobacterium tuberculosis (MTB) isolates (n=692) from Mpumalanga province was assessed. In total, 692 (64%) MTB strains from cases with pulmonary TB were tested for susceptibility against rifampicin, isoniazid, ethambutol, and streptomycin using the MGIT 960 instrument. Two hundred and nine (30.2%) strains were resistant to one or more drugs. Resistance to one drug ranged from 1.4% for ethambutol to 17.7% for rifampicin. The prevalence of MDR-TB ranged from 6.7% for three drugs to 34% for four drugs, with significant predictors being patients' age-groups of 25-54 years (p=0.0012) and >55 years (p=0.007). The result showed a high level (58.4%) of MDR-TB from cases in Mpumalanga province. To achieve a higher cure rate in this province, drug-susceptibility tests must be done for every case.
Journal of Health Population and Nutrition 02/2010; 28(1):7-13. · 0.95 Impact Factor
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ABSTRACT: In a recent study in northern South Africa, the seroprevalence of Entamoeba histolytica infection among 257 HIV-positive and 117 HIV-negative individuals was determined, using an ELISA for the detection of antibodies reacting with the parasite's galactose/-acetyl-D-galactosamine(Gal/GalNAc)-inhibitable adherence lectin. Overall, 34.0% of the 374 participants (36.1% of the females and 28.1% of the males) were found seropositive for E. histolytica. Although all age-groups were affected by the amoebic pathogen, the subjects aged 50-59 years had the highest seroprevalence (69.2%). The seroprevalence of E. histolytica was also significantly higher among the HIV-positive subjects than among the HIV-negative (42.8% v. 14.5%; chi(2)=28.65; P<0.0001). Among the HIV-positive subjects, those with fewer than 200 CD4+ cells/microl were relatively more likely to be seropositive for E. histolytica (60.3% v. 43.8%; chi(2)=4.016; P=0.045). This is the first report indicating a positive association between E. histolytica infection and HIV in South Africa. Further studies, for example to determine the occurrence of diarrhoea or liver abscess in the study area, in relation to seropositivity for E. histolytica and/or HIV, are now needed.
Annals of Tropical Medicine and Parasitology 01/2010; 104(1):55-63. · 1.43 Impact Factor
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ABSTRACT: In the present study, a cross-sectional survey of intestinal parasitic and bacterial infections in relation to diarrhoea in Vhembe district and the antimicrobial susceptibility profiles of isolated bacterial pathogens was conducted. Stool samples were collected from 528 patients attending major public hospitals and 295 children attending two public primary schools and were analyzed by standard microbiological and parasitological techniques. Entamoeba histolytica/E. dispar (34.2%) and Cryptosporidium spp. (25.5%) were the most common parasitic causes of diarrhoea among the hospital attendees while Giardia lamblia (12.8%) was the most common cause of diarrhoea among the primary school children (p < 0.05). Schistosoma mansoni (14.4%) was more common in non-diarrhoeal samples at both hospitals (16.9%) and schools (17.6%). Campylobacter spp. (24.9%), Aeromonas spp. (20.8%), and Shigella spp. (8.5%) were the most common bacterial causes of diarrhoea among the hospital attendees while Campylobacter (12.8%) and Aeromonas spp. (12.8%) were most common in diarrhoeal samples from school children. Vibrio spp. was less common (3% in the hospitals) and were all associated with diarrhoea. Antimicrobial resistance was common among the bacterial isolates but ceftriaxone (91%) and ciprofloxacin (88.6%) showed stronger activities against all the organisms. The present study has demonstrated that E. histolytica/dispar, Cryptosporidium, Giardia, and Cyclospora are common parasitic causes of diarrhoea in Vhembe district while Campylobacter spp. and Aeromonas are the most common bacterial causes of diarrhoea in Vhembe district of South Africa.
Journal of Health Population and Nutrition 12/2009; 27(6):739-45. · 0.95 Impact Factor
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ABSTRACT: The polymorphism of the serine-rich Entamoeba histolytica protein (SREHP) among isolates obtained from different geographic regions was analyzed by a nested PCR followed by restriction analysis. Thirteen different profiles were generated from 23 E. histolytica isolates from Cameroon, Zimbabwe and South Africa while 20 others were generated from 38 E. histolytica PCR positive stool samples from South Africa. One of the profiles was common to isolates from Cameroon, Zimbabwe and South Africa and constituted the most prevalent (26.1%) of all the profiles. However, profiles unique to each country were also observed amongst the samples. A non-significant difference was observed between isolates from diarrheic and non-diarrheic samples. Of interest, of the five HIV positive stool samples three had the same profile indicating the possibility that some E. histolytica strains might be more common/pathogenic in immuno-compromised individuals. The results obtained showed that African isolates of E. histolytica may possess extremely complex genetic structures independent of geographic location. This study indicates that certain profiles might be responsible for the presentation of intestinal amoebic symptoms. However, more extended studies need to be performed in order to confirm these observations.
Experimental Parasitology 04/2008; 118(3):354-61. · 2.12 Impact Factor
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ABSTRACT: In the present study, the prevalence and species distribution of Cryptosporidium among school children and hospital patients in the Venda region of South Africa was determined. Real time PCR (qPCR) was used for initial screening to detect positive samples while a nested PCR followed by restriction fragment length polymorphism was used to determine the species genotype. From a total of 244 stool samples tested, 44 (18%) had Cryptosporidium with no significant difference (chi(2)=0.04; P=0.841) between samples collected from patients attending hospitals 36/197 (18%) and the samples from primary schools 8/47 (17%). The age groups most affected were those from 2 to 5 years old (28.6%) and 50 to 59 years old (50.0%). Cryptosporidium was detected in 4 (12.5%) of the 31 HIV positive individuals. Fifty-seven percent of the Cryptosporidium positive samples were diarrheic and 26 (59.1%) had elevated lactoferrin content. C. hominis (82%) was more common than C. parvum (18%). This study has demonstrated the high prevalence of Cryptosporidium infections in the Venda region and its implications in causing diarrhea and inflammation.
Experimental Parasitology 01/2007; 114(4):314-22. · 2.12 Impact Factor
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ABSTRACT: The microbial quality of several, usually untreated, surface domestic water sources, used by rural communities in the Venda Region of South Africa, was assessed to gauge their fitness for human consumption and to highlight the possible impact of waterborne diseases. The water sources studied were six points on the Levubu River and the rivers Mutale, Ngwedi, Tshinane, Makonde, Mutshindudi and Mudaswali. Total and faecal coliform, heterotrophic bacteria, enterococci and coliphage counts were used as indicators/surrogates to estimate the degree of bacterial and viral contamination respectively by standard methods. The presence of potential bacterial agents of diarrhoea such as Salmonella, Shigella, Campylobacter, Plesiomonas, Aeromonas and Vibrio was also determined. Results showed that the ranges of counts with regard to all the water sources investigated were 2.9 x 10(2) - 6.3 x 10(4) CFU/100 mL for faecal coliforms, 6.0 x 10(2) - 3.7 x 10(4) CFU/100 mL for total coliforms, 1.8 x 10(2) - 1.3 x 10(6) CFU/mL for heterotrophic plate count, 1.0 x 10(1) - 3.7 x 10(4) CFU/100 mL for enterococci and 0-13 PFU/100 mL for coliphages. These values are far higher than the acceptable maximum limits prescribed for South Africa by the Dept of Water & Forestry and the Water Research Commission - 0 CFU/100 mL, 5 CFU/100 mL, 1.0 x 10(2) CFU/mL, 0 CFU/100 mL and 1 PFU/100 mL for faecal coliforms, total coliforms, heterotrophic bacteria, enterococci and coliphages respectively. Salmonella, Shigella, Vibrio cholerae, Campylobacter, Aeromonas and Plesiomonas were isolated from several of the water sources investigated. The use of these water sources for drinking and domestic purposes poses a serious threat to the health and well being of the users and calls for urgent government intervention.
Water Science & Technology 01/2003; 47(3):59-64. · 1.12 Impact Factor
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ABSTRACT: In the present study, the prevalence and species distribution of Cryptosporidium among school children and hospital patients in the Venda region of South Africa was determined. Real time PCR (qPCR) was used for initial screening to detect positive samples while a nested PCR followed by restriction fragment length polymorphism was used to determine the species genotype. From a total of 244 stool samples tested, 44 (18%) had Cryptosporidium with no significant difference (χ2 = 0.04; P = 0.841) between samples collected from patients attending hospitals 36/197 (18%) and the samples from primary schools 8/47 (17%). The age groups most affected were those from 2 to 5 years old (28.6%) and 50 to 59 years old (50.0%). Cryptosporidium was detected in 4 (12.5%) of the 31 HIV positive individuals. Fifty-seven percent of the Cryptosporidium positive samples were diarrheic and 26 (59.1%) had elevated lactoferrin content. C. hominis (82%) was more common than C. parvum (18%). This study has demonstrated the high prevalence of Cryptosporidium infections in the Venda region and its implications in causing diarrhea and inflammation.
Experimental Parasitology.
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ABSTRACT: Molecular techniques were used to characterise clinical and environmental isolates of non-typhoidal Salmonella obtained from environmental (water and food) and clinical (stool) specimens in rural Venda communities, Limpopo Province of South Africa. Results obtained revealed that out of a total of 457 environmental and clinical isolates examined for the prevalence of Salmonella isolates, 293 (64%) were positive. Results further revealed that 266 (75%) out of 375 environmental samples screened and 27 (27%) of the clinical stool specimens were positive for Salmonella respectively. Phenotypic differentiation indicated that all 27 (100%) clinical specimens and 44 (15%) of the environmental isolates were identified as Salmonella subspecies I (human associated isolates) and a total of 222 (76%) as Salmonella subspecies II-VI (environmentally associated isolates) which are rarely isolated from humans. Only strains of Salmonella subspecies I were subjected to molecular characterization using PCR techniques to rapidly identify Salmonella typhimurium and Salmonella enteriditis. Sixteen (36%) environmental Salmonella isolates, 26 (96%) of clinical isolates and a Salmonella typhimurium reference strain gave a 559 bp amplified fragment with the Fli l5-Tym primer set only and did not a 488 bp amplified fragment with the AO58-AO1 primer set. These isolates were classified as Salmonella typhimurium. Only one clinical isolate (4%) and a Salmonella enteriditis reference strain produced a 488 bp fragment with the AO58-AO1 primer set and was classified as Salmonella enteriditis. No 559 or 488 bp amplified products were found for the remaining 28 (39%) environmental Salmonella subspecies I isolates. It is concluded that Salmonella isolates from stool specimens and environmental samples demonstrated the same PCR banding pattern with a 559 bp fragment, indicating relatedness. This may partly explain the endemic circulation of strains between the human population and the environment.
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C L Obi,
J Ramalivhana,
M.N.B. Momba,
B. Onabolu,
J.O. Igumbor,
M. Lukoto,
T.B. Mulaudzi, P O Bessong,
E.L. Jansen van Rensburg,
E Green,
S Ndou
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ABSTRACT: Antibiotic resistance profiles and the correlation of enteric bacterial pathogens from HIV positive individuals with and without diarrhoea and their household drinking water were determined using the Kirby Bauer disk diffusion and polymerase chain reaction methods respectively. The sef gene of Salmonella enteritidis was amplified with the primer pair sefA-1 and sefA-2. The fliC gene of Salmonella typhimurium was amplified with the primer pair flicA-1 and flicA-2. Heat-labile toxin (LT) primers (Lta and LTb) were used to amplify Escherichia coli isolates and VirA1 and VirA2 for the Vir A gene of Shigella dysenteriae . Results of antibiotic resistance profiles of enteric bacterial pathogens isolated from stool samples of HIV positive and negative individuals with and without diarrhea and their household drinking water showed very similar drug resistance patterns. Over 90% of all the organisms isolated from the various study cohorts showed resistance to penicillin, cloxacillin and amoxicillin. Conversely, almost all the organisms were sensitive to ciprofloxacin, gentamycin, meropenem and imipenem. About 50% of E. coli isolated from the various studycohortsshowed multipleantibiotic resistance to penicillin, amoxicillin, ampicillin, erythromycin, tetracycline, doxycycline and cotrimoxazole ( PR, AR, APR, ER, TR, DXTR, and TSR ) whereas less than 10% resistance was consistently reported for ofloxacin, gentamycin, meropenem cefotaxime, cefuroxime and imipenem ( OFXS, GMS, MEMS, CTXS, CXMS and IMIS ). The majority of Salmonella and Shigella isolates from all the groups were sensitive to ciprofloxacin, gentamicin, amikacin, meropenem, imipenem, nalidixic acid, kanamycin, piperacillintazo bactam, cefuroxime, doxycyclin, cefepime and ceftazidime (CIPS, GMS, AKS, MEMS, IMIS, NAS, KNS, DXTS, CXMS, CPMS, CAZS and PTZS). For Campylobacter, over 30% of the isolates were resistant to erythromycin, ampicillin, tetracycline, cotrimoxazole and ceftazidime (ER, APR TSR and CAZR) whereas over 85% were susceptible to ciprofloxacin, ofloxacin, gentamycin, amikacin, meropenem, and nalidixic acid (CIPS, OFXS, GMS, AKS, MEMS and NAS). In addition to penicillin, amoxicillin, ampicillin and erythromycin, Aeromonas and Plesiomonas spp were more resistant to chloramphenicol, but were susceptible to ciprofloxacin, gentamycin, amikacin, meropenem, imipenem and nalidixic acid (CIPS, GMS, AKS, MEMS, IMIS and NAS). Polymerase Chain Reaction (PCR) experiments using targeted species genes of S. enteritidis, S. typhimurium, E. coli, Sh. dysenteriae showed that isolates from stool samples of HIV positive and HIV negative individuals with and without diarrhoea were also present in the household drinking water of the same study cohorts, suggesting that drinking water may have been the sources of the organisms in stool sample. Furthermore, by showing that the primers were able to amplify the genes in both clinical and environmental isolates, the link between the virulence of the pathogens was established.
African Journal of Biotechnology (ISSN: 1684-5315) Vol 6 Num 8.
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ABSTRACT: The polymorphism of the serine-rich Entamoeba histolytica protein (SREHP) among isolates obtained from different geographic regions was analyzed by a nested PCR followed by restriction analysis. Thirteen different profiles were generated from 23 E. histolytica isolates from Cameroon, Zimbabwe and South Africa while 20 others were generated from 38 E. histolytica PCR positive stool samples from South Africa. One of the profiles was common to isolates from Cameroon, Zimbabwe and South Africa and constituted the most prevalent (26.1%) of all the profiles. However, profiles unique to each country were also observed amongst the samples. A non-significant difference was observed between isolates from diarrheic and non-diarrheic samples. Of interest, of the five HIV positive stool samples three had the same profile indicating the possibility that some E. histolytica strains might be more common/pathogenic in immuno-compromised individuals. The results obtained showed that African isolates of E. histolytica may possess extremely complex genetic structures independent of geographic location. This study indicates that certain profiles might be responsible for the presentation of intestinal amoebic symptoms. However, more extended studies need to be performed in order to confirm these observations.
Experimental Parasitology.
