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Prevalence, predilection sites and pathological findings of <i>Taenia multiceps</i> coenuri in slaughtered goats from south-east Iran Full text
2012
Reza Kheirandish | Masoud Sami | Shahrzad Azizi | Mohammad Mirzaei
Coenurosis is a zoonotic disease in a variety of ruminants caused by the metacestode of<em> Taenia multiceps</em>. The coenuri in the brain and spinal cord of sheep and goats have been identified as Coenurus cerebralis whilst those reported in other tissues have been named Coenurus gaigeri. This study was conducted during the spring and summer of 2011. Out of 25 739 goats inspected in slaughterhouses, 23 carcasses (0.09%) revealed one or multiple visible swellings on the different muscles and visceral organs. The coenuri, of variable sizes, were found mainly in the muscles of the thigh, shoulder and neck, and were less common in the abdominal muscles and subcutaneous tissues. Coenuri were also found in the diaphragm, tongue, intercostal muscles, lung, parotid area and tunica adventitia of the aorta in a goat with severe infection. The brains of slaughtered goats that had coenuri in their skeletal muscles were examined and coenuri were found in two specimens (8.69%). The coenuri were located in the occipital lobe, the anterior part of the right cerebrum and the parietal lobe of the left cerebrum. Histopathologically, coenuri in the brain caused pressure atrophy and liquefactive necrosis in the surrounding tissues, hyperaemia, perivascular cuffing, neuronal degeneration, neuronophagia, satellitosis, diffuse microgliosis and astrocytosis. Coenuri in the skeletal muscles caused degenerative and necrotic changes, hyalinisation and myositis. In the lung, tissues around the coenurus revealed atelectasis and focal interstitial fibrosis. In the present study, concurrent occurrence of coenuri in the central nervous system and skeletal muscles supports the hypothesis that C. cerebralis and C. gaigeri are different names for the metacestodes of the same species of tapeworm.
Show more [+] Less [-]Rift Valley fever: Real or perceived threat for Zambia? Full text
2012
George Dautu | Calvin Sindato | Aaron S. Mweene | Kenny L. Samui | Polly Roy | Robert Noad | Janusz Paweska | Phelix A.O. Majiwa | Antony Musoke
Rift Valley fever: Real or perceived threat for Zambia? Full text
2012
George Dautu | Calvin Sindato | Aaron S. Mweene | Kenny L. Samui | Polly Roy | Robert Noad | Janusz Paweska | Phelix A.O. Majiwa | Antony Musoke
Rift Valley fever (RVF) in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE) disease occurrence data on RVF for the period 2005−2010 in the Southern Africa Development Community (SADC) was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.
Show more [+] Less [-]Rift Valley fever: Real or perceived threat for Zambia? Full text
2012
Dautu, George(University of Zambia Department of Disease Control) | Sindato, Calvin(National Institute for Medical Research) | Mweene, Aaron S.(University of Zambia Department of Disease Control) | Samui, Kenny L.(University of Zambia Department of Disease Control) | Roy, Polly(London School of Hygiene and Tropical Medicine) | Noad, Robert(Royal Veterinary College) | Paweska, Janusz(National Institute for Communicable Diseases) | Majiwa, Phelix A.O.(Onderstepoort Veterinary Institute) | Musoke, Antony J.(Onderstepoort Veterinary Institute)
Rift Valley fever (RVF) in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE) disease occurrence data on RVF for the period 2005-2010 in the Southern Africa Development Community (SADC) was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.
Show more [+] Less [-]Ectoparasites of sheep in three agro-ecological zones in central Oromia, Ethiopia Full text
2012
Bersissa Kumsa | Kebede Beyecha | Mesula Geloye
A cross-sectional study was conducted to determine the prevalence and risk factors for ectoparasites infestation in sheep in three agro-ecological zones in central Oromia, Ethiopia, from October 2009 to April 2010. The study revealed that 637 (48.1%) of the 1325 sheep examined were infested with one or more ectoparasites. The ectoparasites identified were <em>Bovicola ovis</em> (27.2%), <em>Melophagus ovinus</em> (16.4%), <em>Ctenocephalides</em> sp. (2.3%), <em>Linognathus africanus</em> (1.2%), <em>Linognathus ovillus </em> (0.3%),<em> Sarcoptes</em> sp. (1.2%), <em>Amblyomma variegatum</em> (4.4%), <em>Rhipicephalus evertsi evertsi</em> (1.9%), <em>Rhipicephalus pravus</em> (1.9%), <em>Rhipicephalus</em> (<em>Boophilus</em>) <em>decoloratus</em> (1.1%), <em>Rhipicephalus sanguineus</em> (0.9%), <em>Rhipicephalus praetextatus</em> (1.1%) and <em>Hyalomma truncatum</em> (1.6%). Statistically significant difference was observed in prevalence of <em>B. ovis</em> amongst study agroecological zones: highland 36.6%, midland 20.9% and lowland 14.0%. Significantly higher prevalence was recorded in highland agroecological zone. A significantly (OR = 0.041, <em>p</em> < 0.001) higher prevalence of <em>M. ovinus</em> in the highland (31.7%) than in both the lowland (0%) and midland (1.9%) was observed. The risk of tick infestation in the lowland and midland was 9.883 times and 13.988 times higher than the risk in the highland, respectively. A significantly higher prevalence of <em>Ctenocephalides</em> species was encountered in both the lowland (OR = 4.738, <em>p</em> = 0.011) and midland (OR = 8.078, <em>p</em> = 0.000) than in the highland agro-ecological zone. However, a significant difference (<em>p</em> = 0.191) amongst agro-ecological zones was not found for the prevalence of <em>Linognathus</em> and <em>Sarcoptes </em>species. Statistically significant variation (<em>p</em> > 0.05) was never recorded in the prevalence of all the identified species of ectoparasites between male and female sheep hosts. However, a significantly (<em>p</em> = 0.006) higher prevalence of<em> B. ovis</em> was recorded between young and adult sheep. The risk of <em>B. ovis</em> infestation was 1.45 times higher in young than the adult sheep. Furthermore, a significantly (<em>p</em> < 0.001) higher prevalence of <em>M. ovinus</em>, <em>B. ovis</em> and <em>Sarcoptes</em> sp. was found between sheep with poor and a good body condition. The ever increasing threat of ectoparasites on overall sheep productivity and tanning industry in Ethiopia warrants urgent control intervention. Further studies on the role of ectoparasites in transmission of diseases to sheep, zoonotic importance, comparative prevalence and load, and the importance of sheep as alternative hosts in different agroecological zones, breeds and management systems in Ethiopia are recommended so as to design applicable control programme in the country.
Show more [+] Less [-]MSc One Health Analytical Epidemiology Full text
2012
Martin C. Simuunza
Leptospirosis in South Africa Full text
2012
Adrienne Saif | John Frean | Jenny Rossouw | Anastasia N. Trataris
Leptospirosis is a common zoonosis worldwide. It has a ubiquitous distribution and causes a wide spectrum of disease. Leptospirosis therefore has a broad reservoir host range, and many infected species of animals excrete leptospires in their urine, which leads to contamination of soil and water. Typical descriptions of the disease include a biphasic (anicteric form) and fulminant disease in the icterohaemorrhagic form. Only a few local case reports of human leptospirosis have been published, the most recent one being in 1974. A rodent-related zoonosis study (RatZooMan) was conducted from 2003 until 2006 in three provinces (Limpopo, KwaZulu-Natal and the Eastern Cape). Of the people sampled in Cato Crest (Durban, KwaZulu-Natal Province), 43/217 (19.8%) were seropositive for leptospirosis. Of the clinical samples sent to the Special Bacterial Pathogens Reference Unit from all over the country for testing in 2009, 16/176 (9%) were IgM positive; in 2010 and January 2011 to May 2011, 14/215 (6.5%) and 12/96 (12.5%), respectively, were IgM positive. The apparent incidence of leptospirosis in the South African population is moderately high based on the detected positives in suspected cases; it is thought that the circulating infection rate may be even higher when looking at the RatZooMan results. This may be due to underreporting and undiagnosed cases. Communities in informal settlements in urban areas are especially at risk as infected rodent populations are a continuous source of transmission.
Show more [+] Less [-]Orf in South Africa: Endemic but neglected Full text
2012
Alessandra Scagliarini | Silvia Piovesana | Filippo Turrini | Federica Savini | Fortune Sithole | Cheryl M. McCrindle
A survey amongst sheep and goat producers and veterinarians was undertaken to collect epidemiological data on orf in South Africa. Previous epidemiological studies on the presence of the disease in the country have not been documented and this report is the first descriptive epidemiological study of orf in South Africa. A seven-month investigation, realised by direct and indirect interviews and field observation, enabled us to outline incidence and risk factors of this disease and to better understand how the local farmers in rural areas relate to it. The results may contribute to better management of the disease in rural areas. By means of molecular analyses the phylogenetic relationships between field isolates from different areas have been identified. The findings gave a first important contribution to the general assessment of the economic impact of orf virus infections and the extent of the risk to human health.
Show more [+] Less [-]Descriptions of strigea cercariae from the Gauteng and North West Provinces, South Africa Full text
2012
Esmey B.E. Moema | Pieter H. King | Chantelle Baker
Freshwater snails are known to serve as first intermediate hosts for various parasitic diseases such as schistosomosis, amphistomosis and fasciolosis. Two freshwater snail species, <em>Lymnaea natalensis</em>, Krauss 1848 and <em>Bulinus tropicus</em>, Krauss 1848 were sampled from five localities in Gauteng and one locality in the North West Province from 2007 to 2010. These snails were collected in order to study their cercarial sheddings. They were found to be infected with three different types of strigea cercariae, of which the morphology was studied using standard light and scanning electron microscopy techniques.
Show more [+] Less [-]Comparing effects of freezing at -196 °C and -20 °C on the viability of mastitis pathogens Full text
2012
Inge-Marie Petzer | Joanne Karzis | Theodorus J. van der Schans | Johanna C. Watermeyer | Norman Mitchell-Innes | Stephanie Eloff | Geoffrey T. Fosgate
Comparing effects of freezing at -196 °C and -20 °C on the viability of mastitis pathogens Full text
2012
Inge-Marie Petzer | Joanne Karzis | Theodorus J. van der Schans | Johanna C. Watermeyer | Norman Mitchell-Innes | Stephanie Eloff | Geoffrey T. Fosgate
The aim of this study was to compare the effects of cryopreservation at approximately -196 °C in liquid nitrogen (N) and freezing at approximately -20 °C in a freezer, on the viability and survival of eight different mastitogenic bacteria inoculated in milk. Bacteria were frozen at approximately -20 °C in a freezer and cryopreserved at approximately -196 °C in liquid nitrogen. An effective preservation method was needed for follow-up samples from cows identified in the South African National Milk Recording Scheme (NMRS) with somatic cell counts above 250 000 cells/mL milk. The organisation responsible for sample collection of the NMRS milk samples also provides producers with liquid nitrogen for their semen flasks at the collection sites. This existing mode of storage and transport could therefore be utilised. Ten samples of each organism were thawed and cultured bi-weekly until week 18 for both temperature treatments. An additional sampling was performed at week 30 for samples frozen at approximately -20 °C. Freezing and cryopreservation did not impair subsequent isolation of Streptococcus dysgalactiae, Streptococcus uberis, Enterococcus faecalis, Staphylococcus aureus (STH) (phage type lytic group III) or Sta. aureus (STA) (phage typed, other than lytic group III). Survival was indicated by the isolation of bacteria from samples, and viability by the strength of growth of the bacteria isolated. The survival of Streptococcus agalactiae decreased after week 12 and Escherichia coli after week 16 of freezing, but both organisms survived under cryogenic preservation until week 18. Coagulase-negative staphylococci survived until week 18 for both freezing and cryogenic preservation. Both storage methods could thus contribute to the improvement of a pro-active approach towards udder health management in South African dairy herds.
Show more [+] Less [-]Diversity of metazoan parasites of the Mozambique tilapia, <i>Oreochromis mossambicus</i> (Peters, 1852), as indicators of pollution in the Limpopo and Olifants River systems Full text
2012
Grace N. Madanire-Moyo | Wilmien J. Luus-Powell | Pieter A. Olivier
Diversity of metazoan parasites of the Mozambique tilapia, <i>Oreochromis mossambicus</i> (Peters, 1852), as indicators of pollution in the Limpopo and Olifants River systems Full text
2012
Grace N. Madanire-Moyo | Wilmien J. Luus-Powell | Pieter A. Olivier
Aquatic systems are affected by a variety of anthropogenic activities that decrease water quality through the introduction of organic and inorganic pollutants. To investigate the relationship between fish parasite communities and water quality, metazoan parasites were examined in 140 specimens of the Mozambique tilapia (Oreochromis mossambicus) sampled in three lakes in the Limpopo Province, namely the Luphephe–Nwanedi Dams (regarded as unpolluted), the Flag Boshielo Dam (regarded as moderately polluted) and a return water dam on a mine site (regarded as polluted). The monogenean parasites Cichlidogyrus halli, digenean larval stages of Clinostomum and Diplostomum spp. and a gryporynchid cestode were found in or on O. mossambicus in all the sampled sites. The distribution of monogeneans (Cichlidogyrus sclerosus, Cichlidogyrus dossoui, Cichlidogyrus tilapiae, Scutogyrus longicornis and three Enterogyrus spp.), metacercarial stages of two digeneans (Neascus and Acanthostomum spp.) and nematodes (an unidentified nematode, Contracaecum sp., Paracamallanus cyathopharynx and Procamallanus laevionchus) was limited to the unpolluted and moderately polluted lakes. Larval stages of Diplostomum sp. were present in O. mossambicus collected from the unpolluted and polluted sites. The variability of the calculated infection indices (prevalence, mean abundance and mean intensity) and the parameters of species richness and diversity suggest that the structure of parasite communities are affected by the pollution levels of the water. The unpolluted reference site had the highest species richness and the highest overall parasite abundance values.
Show more [+] Less [-]Diversity of metazoan parasites of the Mozambique tilapia, <i>Oreochromis mossambicus</i> (Peters, 1852), as indicators of pollution in the Limpopo and Olifants River systems Full text
2012
Grace N. Madanire-Moyo | Wilmien J. Luus-Powell | Pieter A. Olivier
Aquatic systems are affected by a variety of anthropogenic activities that decrease water quality through the introduction of organic and inorganic pollutants. To investigate the relationship between fish parasite communities and water quality, metazoan parasites were examined in 140 specimens of the Mozambique tilapia (<em>Oreochromis mossambicus</em>) sampled in three lakes in the Limpopo Province, namely the Luphephe–Nwanedi Dams (regarded as unpolluted), the Flag Boshielo Dam (regarded as moderately polluted) and a return water dam on a mine site (regarded as polluted). The monogenean parasites <em>Cichlidogyrus halli</em>, digenean larval stages of <em>Clinostomum</em> and <em>Diplostomum</em> spp. and a gryporynchid cestode were found in or on <em>O. mossambicus</em> in all the sampled sites. The distribution of monogeneans (<em>Cichlidogyrus sclerosus, Cichlidogyrus dossoui, Cichlidogyrus tilapiae, Scutogyrus longicornis</em> and three <em>Enterogyrus</em> spp.), metacercarial stages of two digeneans (<em>Neascus</em> and <em>Acanthostomum</em> spp.) and nematodes (an unidentified nematode, <em>Contracaecum </em>sp., <em>Paracamallanus cyathopharynx</em> and <em> Procamallanus laevionchus</em>) was limited to the unpolluted and moderately polluted lakes. Larval stages of <em>Diplostomum</em> sp. were present in <em>O. mossambicus</em> collected from the unpolluted and polluted sites. The variability of the calculated infection indices (prevalence, mean abundance and mean intensity) and the parameters of species richness and diversity suggest that the structure of parasite communities are affected by the pollution levels of the water. The unpolluted reference site had the highest species richness and the highest overall parasite abundance values.<p><strong>How to cite this article:</strong> Madanire-Moyo, G.N., Luus-Powell, W.J. & Olivier, P.A., 2012, ‘Diversity of metazoan parasites of the Mozambique tilapia, <em>Oreochromis mossambicus</em> (Peters, 1852), as indicators of pollution in the Limpopo and Olifants River systems’, <em>Onderstepoort Journal of Veterinary Research </em>79(1), Art. #362, 9 pages. http://dx.doi.org/10.4102/ojvr.v79i1.362</p>
Show more [+] Less [-]Identification of the plague reservoir in an endemic area of Zambia Full text
2012
Bernard M. Hang’ombe | I. Nakamura | D. Kaile | A.S. Mweene | K.L. Samui | B.S. Kilonzo | H. Sawa | C. Sugimoto | B. Wren
Yersinia pestis, the bacterial agent of plague, is primarily a parasite of wild rodents that persists in permanent, discrete enzootic foci throughout the world. The disease is transmitted in humans by bites from fleas of wildlife rodent species. Therefore surveillance is the ultimate public health solution through plague detection in domestic dogs, other carnivores and wild rodents. The investigations of die-offs amongst plague-susceptible colonial rodents are also significant to determine the presence of Y. pestis in a susceptible population. This study details the identification of the plague reservoir in a suspected endemic area of Zambia. The study was undertaken through rodent investigation for the presence of Y. pestis. A total of 105 rodents were sampled routinely and during a suspected plague period. On dissection 4 (3.81%, 95% CI: 1.23−10.0) rodents sampled during an outbreak showed signs of spleen enlargement. The blood, liver, lymph nodes and spleen of each rodent were subjected to culture on 6% sheep blood agar and MaCconkey agar. Colonies obtained were identified as Y. pestis by colony morphologic features, biochemical profiles, mouse inoculation assay and polymerase chain reaction (PCR). The PCR primers used targeted the Y. pestis plasminogen activator gene, chromosomal ferric iron uptake regulation gene and the outer membrane protein B gene. The isolates were also subjected to antibiotic sensitivity tests using the disk diffusion method on Mueller-Hinton agar with sensitivity being observed with ampicillin, amoxicillin, chloramphenicol, gentamycin, streptomycin, tetracycline and trimethoprim-sulfamethoxazole. The findings, identifies a natural reservoir of Y. pestis in Zambia providing the public health officials with a definite host for the control strategy.
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