Browsing by Author "Mwita, Chacha"
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Item Detection of Porcine Cysticercosis in Meat Juice Samples from Infected Pigs(Springer, 2021-02-15) Maganira, Justine; Kidima, Winifrida; Mwita, Chacha; Hoglund, JohanBackground Seroprevalence of porcine cysticercosis has been generally studied using enzyme-linked immunosorbent assays (ELISA) detecting either antigens or antibodies in sera. However, serum is not always readily available. The objective of this study was to assess the diagnostic potential of meat juice in detecting porcine cysticercosis using a cysticercosis antibody ELISA. Methods Sera and meat juice samples from 13 different organs/tissues were collected from nine pigs naturally infected with cysticercosis and from six uninfected pigs reared under hygienic conditions. The sensitivity of the cysticercosis antibody ELISA in detecting porcine cysticercosis in meat juice samples was compared to that in serum samples from the same pigs. Results Using sera, cysticercosis was detected in all nine pigs harbouring cysticerci, but not in those reared under hygienic conditions. The sensitivity of the ELISA was highest in meat juice extracted from the diaphragm (100%), heart (89%) and neck muscle (78%) of the nine infected pigs, whereas it varied between 0 and 44% in the other samples. Conclusion To the best of our knowledge, this is the first study for T. solium cysticercosis serology to use meat juice. Our results show that meat juice from pig carcass organs or muscles is a promising diagnostic specimen for the detection of porcine cysticercosis. More studies including a large sample size of pigs with varying degrees of cysticercosis infection are needed to further prove this concept.Item Determinants of the parasite community of clariid fishes from Lake Victoria, Tanzania(Cambridge University Press, 2008) Mwita, Chacha; Gamba, NkwengulilaThe factors that determine parasite assemblages among the clariid fishes of Lake Victoria, Tanzania were studied between August 2003 and February 2005. Six hundred and fifty-six fish belonging to seven species were necropsied and examined for parasites, from which 31 species of metazoan parasites were recorded. The community was dominated by the nematodes both in species and numbers. Most species were generalists with only two trematodes, Diplostomum mashonense and Tylodelphys species, being specialists of Clarias gariepinus. Ten species were considered core and predictable. Parasite species richness, number of individuals per host and Shannon–Wiener diversity indices were generally high. At the compound community level, a mean number of 7.8 parasites were shared among different species of fish and the maximum number of parasites species per fish at the infracommunity level was seven. Levels of similarity in parasite species richness at the component community level ranged from 29.6 to 61.5%. The study concludes that parasite communities in clariid fishes of Lake Victoria are structured by ecological factors. At the infracommunity level, host size, diet and vagility promoted a richer parasite community. At the compound level, two factors were crucial, namely the intermixing of the waters in the lake and the predominant and mobile C. gariepinus.Item Determinants of the Parasite Community of Clariid Fishes from Lake Victoria, Tanzania(2008) Mwita, Chacha; Nkwengulila, GambaThe factors that determine parasite assemblages among the clariid fishes of Lake Victoria, Tanzania were studied between August 2003 and February 2005. Six hundred and fifty-six fish belonging to seven species were necropsied and examined for parasites, from which 31 species of metazoan parasites were recorded. The community was dominated by the nematodes both in species and numbers. Most species were generalists with only two trematodes, Diplostomum mashonense and Tylodelphys species, being specialists of Clarias gariepinus. Ten species were considered core and predictable. Parasite species richness, number of individuals per host and Shannon –Wiener diversity indices were generally high. At the compound community level, a mean number of 7.8 parasites were shared among different species of fish and the maximum number of parasites species per fish at the infracommunity level was seven. Levels of similarity in parasite species richness at the component community level ranged from 29.6 to 61.5%. The study concludes that parasite communities in clariid fishes of Lake Victoria are structured by ecological factors. At the infracommunity level, host size, diet and vagility promoted a richer parasite community. At the compound level, two factors were crucial, namely the intermixing of the waters in the lake and the predominant and mobile C. gariepinus.Item Determination of Heavy Metal Content in Water, Sediment and Microalgae from Lake Victoria, East Africa(Bentham Open, 2011) Ogoyi, Dolington O.; Mwita, Chacha; Nguu, Edward K; Shiundu, Paul M.Lake Victoria, which is the largest fresh water lake in Africa, represents a unique ecosystem that has the largest fresh water fishery in the continent. However, increased anthropogenic activities has increased the potential pollution of the lake especially the heavy metal pollutants which may be toxic to humans and aquatic fauna. There is need therefore for continuous monitoring of pollution levels in the lake. Samples of water, soil sediments and algae were collected in dry, long and short rainy periods of 2008 and analyzed for heavy metal by Atomic Absorption Spectrophotometry. The highest concentration of trace metals were found in sediment samples with Zn having the highest mean concentration values in both Winam (1.019 ppm) and Mwanza gulf (0.889 ppm). The mean concentration of Pb was higher in water samples from Winam gulf (0.823 ppm), while Hg in microalgae samples from Winam gulf had a mean concentration of 0.000148 ppm. The highest concentration of Zn (1.589 ppm) was determined in the sediment samples from Kirumba bay of the Mwanza gulf and the lowest was in sediments from Kishimba bay (0.327 ppm). Levels of trace metals in microalgae were not significant in different sites of the Mwanza Gulf. Like in the Mwanza gulf, levels of Zn was high in sediments from all the sites sampled in Winam Gulf, the highest recorded at Kisat. Pb levels were highest in the water samples from Hippo point, whereas concentration levels of Cd, Cr and Hg were lowest in all the four sites sampled. The maximum biomass of microalgae occurred at Kisat during the short rain season (November-December) followed by Kamito in the same season.Item Indigenous Knowledge, Practices, Beliefs and Social Impacts of Porcine Cysticercosis and Epilepsy in Iringa Rural(Scientific Research, 2014) Mwita, Chacha; Yohana, Coletha; Nkwengulila, GambaPorcine Cysticercosis (PCC) and Human Cysticercosis (HCC)/Neurocysticercosis (NCC) are a burden to the community owing to the reduced value of animals, associated costs of treatment, decreased labour productivity and social discrimination. There is limited knowledge on the management and prevention of PCC and epilepsy in Iringa rural. Therefore, the present study aimed at assessing indigenous knowledge, practices, attitudes and social impacts of PCC and epilepsy in Iringa rural district. A total of 588 people participated in the survey whereby 306 were pig farmers, 223 non-pig farmers and 59 families with epileptic individuals. It was found that 49.8% (χ2 = 0.003, DF = 1, p = 0.954) of pig keepers were aware of PCC, whereas the remaining 50.2% were not aware (χ2 = 25.5, DF = 1, p < 0.001). The prevalence of late onset epilepsy was significantly higher (62.7%) than that of those who manifested seizures and convulsions in childhood 37.3% (χ2 = 3.814, DF = 1, p = 0.51). People in Iringa rural believe epilepsy is caused by evil spirits, witchcraft and/or inheritance. It was concluded that there was limited knowledge on T. solium cysticercosis and epilepsy. This ignorance is the cause of poor practices, negative beliefs and attitudes that negatively affect the social life of People with Epilepsy (PWE) in communities. This study recommends that health education to raise awareness on cysticercosis/taeniosis and epilepsy should be one of the intervention measures for elimination of cysticercosis and epilepsy in Iringa rural district.Item Life history shifts in an exploited African fish following invasion by a castrating parasite(John Wiley & Sons Ltd., 2020-09-24) Gabagambi, Nestory; Skorping, Arne; Mwita, Chacha; Kihedu, Kwendwa; Mennerat, AdeleEvolutionary theory predicts that infection by a parasite that reduces future host survival or fecundity should select for increased investment in current reproduction. In this study, we use the cestode Ligula intestinalis and its intermediate fish host Engraulicypris sardella in Wissman Bay, Lake Nyasa (Tanzania), as a model system. Using data about infection of E. sardella fish hosts by L. intestinalis collected for a period of 10 years, we explored whether parasite infection affects the fecundity of the fish host E. sardella, and whether host reproductive investment has increased at the expense of somatic growth. We found that L. intestinalis had a strong negative effect on the fecundity of its intermediate fish host. For the noninfected fish, we observed an increase in relative gonadal weight at maturity over the study period, while size at maturity decreased. These findings suggest that the life history of E. sardella has been shifting toward earlier reproduction. Further studies are warranted to assess whether these changes reflect plastic or evolutionary responses. We also discuss the interaction between parasite and fishery-mediated selection as a possible explanation for the decline of E. sardella stock in the lake.Item Molecular phylogeny of the clariid fishes of Lake Victoria, Tanzania, inferred from cytochrome b DNA sequences(The Fisheries Society of the British Isles, Blackwell-synergy, 2008) Mwita, Chacha; Gamba, NkwengulilaMitochondrial DNA cytochrome b (cyt b) sequence variation among the clariid fishes of Lake Victoria and the Malagarasi wetland Tanzania were studied between August 2003 and February 2005. Seven species were sampled and together with 26 cyt b sequences from GenBank were used to reconstruct phylogenetic relationships in the family Clariidae. The study revealed two clades: one consisting of the big-head species, Clarias gariepinus and Heterobranchus longifilis, and the other of small-sized species, Clarias werneri, Clarias alluaudi, Clarias liocephalus and Clariallabes petricola. The study further revealed that the genus Clarias is paraphyletic and that H. longifilis clusters deeply inside the Clarias group. Although H. longifilis is thought to be the oldest in evolutionary age in Tanzania, it is not close to the ancestor of the Clariidae family. The results also showed that C. werneri and C. alluaudi are genetically distinct from each other.Item Parasites of Clarias Gariepinus (Burchell, 1822) (Pisces: Clariidae) From The Mwanza Gulf, Lake Victoria(2005) Mwita, Chacha; Nkwengulila, GambaSeventeen species of parasites were recovered from 1071 Clarias gariepinus examined from the Mwanza Gulf of Lake Victoria. The parasite fauna comprised of four ectoparasites, a Monogenea, Hirudinea, crustacean and a Digenea; and fourteen endoparasites, five nematodes, five trematodes and three cestodes. Twelve parasite species were adults and five were larval forms. Ten were identified to species, six to genus and one to family level. Many species recorded are common to C. gariepinus, a few, e.g. Tylodelphys species is a first record in fish of Africa, thus represents a new host record. Spinitectus petterae is reported for the first time in Tanzania, as such represents a new geographical citing. The proteocephalid cestode is also a new record in this host in Tanzania.Item Phylogenetic Relationships of the Metazoan Parasites of the Clariid Fishes of Lake Victoria Inferred from Partial 18S rDNA Sequences(2010) Mwita, Chacha; Nkwengulila, GambaPhylogenetic relationships among twenty two metazoan parasites recovered from seven species of clariid fish from Lake Victoria were analysed using partial 18S rDNA sequences. The 18S rDNA gene was amplified by polymerase chain reaction, directly sequenced, aligned and phylogenies inferred using maximum parsimony. Heuristic bootstrap MP searches yielded one most parsimonious tree (CI = 61%, HI = 39%), which showed that clariid parasites are monophyletic at higher taxonomic levels (Cestodea, Nematodea, Digenea and Crustacea). However the position of two trematodes (Allocredium mazoensis and Clinostomum sp.) and a nematode (Contracaecum sp.) were not stable. Despite the present findings, the study utilised single species from each taxa, hence further analysis with additional sequences from a multitude of species is recommended to further resolve the phylogeny of the parasites of the clariids in Lake Victoria and elsewhere.Item PHYLOGENETIC RELATIONSHIPS OF THE METAZOAN PARASITES OF THE CLARIID FISHES OF LAKE VICTORIA INFERRED FROM PARTIAL 18S rDNA SEQUENCES(Tanzania Journal of Science (TSJ), 2010) Mwita, Chacha; Gamba, NkwengulilaPhylogenetic relationships among twenty two metazoan parasites recovered from seven species of clariid fish from Lake Victoria were analysed using partial 18S rDNA sequences. The 18S rDNA gene was amplified by polymerase chain reaction, directly sequenced, aligned and phylogenies inferred using maximum parsimony. Heuristic bootstrap MP searches yielded one most parsimonious tree (CI = 61%, HI = 39%), which showed that clariid parasites are monophyletic at higher taxonomic levels (Cestodea, Nematodea, Digenea and Crustacea). However the position of two trematodes (Allocredium mazoensis and Clinostomum sp.) and a nematode (Contracaecum sp.) were not stable. Despite the present findings, the study utilised single species from each taxa, hence further analysis with additional sequences from a multitude of species is recommended to further resolve the phylogeny of the parasites of the clariids in Lake Victoria and elsewhere.Item The Prevalence of Porcine Cysticercosis and Risk Factors for Taeniasis in Iringa Rural District(2013) Yohana, C.; Mwita, Chacha; Nkwengulila, GambaThe present study aimed at determining the prevalence of porcine cysticercosis and associated risk factors for taeniosis in Iringa rural. A total of 110 households rearing pigs from sixteen villages were involved in a survey in which 308 pigs were examined for Cysticercus cysts by antemortem and postmortem methods. The risk factors for taeniosis were assessed and evaluated through questionnaires, interviews and by direct observation. Of 308 pigs examined by lingual palpation, 23 (7.5%, p＜0.001) had cysticerci; the prevalence rates was higher in male pigs than female 16 (69.5%) and 7 (30.4%), respectively. Likewise the prevalence was higher in villages away from the main roads where there were pigs that customarily ran loose or fed human feaces. The triceps muscle had the highest number of cysts 44 (51.1%) and the diaphragm had the lowest 6 (6.9%). Of 4020 people who sought for treatment in five wards per month, 155 (21.8%) had history of intestinal worms, 6 (2.2%) consumed uninspected pork from peoples house, 82 (74.5%) lack tap water, 13 (12%) had no toilets and 40 (22.7%) practiced free range pig husbandry or tethering method. The findings from this study identified community behavioral, household hygiene and environmental practices that should be modified to prevent continued transmission of cysticercosis and taeniosis in Iringa rural district.Item Seroprevalence of circulating taeniid antigens in pigs and associated risk factors in Kongwa district, Tanzania(Elsevier, 2019-10-29) Maganira, Justine; Mwang'onde, Beda; Kidima, Winifrida; Mwita, Chacha; Hoglund, JohanThe aim of this study was to investigate exposure to porcine cysticercosis (PC) and associated risk factors in the Kongwa District, eastern-central Tanzania. For the first time a cross-sectional investigation of the seroprevalence in pigs using a commercial genus specific cysticercosis enzyme linked immunosorbent assay (apDia Ag-ELISA) was undertaken in eastern-central Tanzania. Moreover, the identity of suspected T. solium cysts from pigs in the study area were confirmed by sequencing parasites’ mitochondrial cox1 gene. Structured questionnaires and direct observations were used to investigate risk factors associated with parasite transmission. A total of 102 pig-keeping households were surveyed during the dry season between July and August 2017 and 126 households in the rainy season between March and April 2018. Of the 447 examined pigs, 77 (17%, 95% C.I. 14%e20%) tested positive in the ELISA. Seroprevalence was higher in pigs examined during the rainy (21%, 95% C.I. 16%e26%) than dry (12%, 95% C.I. 7%e17%) season (p ¼ 0.019). Eight cyst-positive-pigs were confirmed to be infected with T. solium by sequencing. Risk factors associated with PC seropositivity included origin of piglets or pigs (OR ¼ 0.27, 95% C.I. 0.13 e0.42, p ¼ 0.001), socioeconomic factors and pig production system (OR ¼ 0.22, 95% C.I. 0.07e0.37, p ¼ 0.005) and sanitation and hygiene practices (OR ¼ 0.19, 95% C.I. 0.04e0.34, p ¼ 0.014). This study has recorded a high Taenia spp. seroprevalence in pigs in Kongwa suggesting the presence of people in the community carrying the adult parasite, Taenia solium. Our findings also suggest risk of infection by T. solium to people in urban centres and cities consuming pigs from rural areas in Kongwa. The high seroprevalence in Kongwa calls for further studies on taeniasis and cysticercosis in the human population in order to determine suitable control strategiesItem Soil contamination by Taenia solium egg DNA in rural villages in Kongwa district, Tanzania(Taylor & Francis, 2020-06-04) Maganira, Justine; Kidima, Winifrida; Mwita, Chacha; Halvarsson, Peter; Hoglund, JohanThe presence ofTaenia solium DNA from eggs in soils around the households in four Tanzanian villages in Kongwa district were analysed in relation to seasonal fluctuations and infection risk implications. A total of 192 pooled soil samples from five sampling points per household were examined by droplet digital Polymerase Chain Reaction (ddPCR) from 96 pigkeeping households both during the dry and rainy seasons. The pooled samples were first processed by a flotation-double sieving technique, followed by screening for worm DNA employing universal primers targeting the mitochondrial cytochrome c oxidase subunit I (cox1) gene of human taeniid species and some other helminths. All DNA positive samples were later confirmed by a specific ddPCR probe assay targeting the mitochondrial cox1 gene of T. solium. A total of 17.2% (n = 33) samples were positive with the universal ddPCR, whereas T. solium DNA was confirmed by the specific ddPCR only in 3.1% (n = 3) of the surveyed households. The detection of T. solium DNA in this study spells out a low risk of exposure to T. solium eggs from contaminated household soil. Based on our results, ddPCR seems to be a promising technology for screening T. solium eggs in soil.Item Spatial Distribution of Parasites along the Gut of the Catfish Clarias Gariepinus (Burchell, 1822) (Clariidae) from the Mwanza Gulf, Lake Victoria(2005) Nkwengulila, Gamba; Mwita, ChachaThe diversity, abundance and spatial distribution of parasites in the alimentary tract of Clarias gariepinus from the Mwanza Gulf were investigated. Ten parasite species were recovered; the Trematoda, Cestoda and Nematoda were each represented by three species while Dolops ranarum was the only crustacean recovered from the posterior part of the buccal cavity. Parasites diversity was highest in the small intestine and the stomach. Although the gut community of C. gariepinus studied was rich in intensity and individual numbers of helminth species, helminth infection in most sections of the gut comprised of monospecific infection and thus cohabiting interspecific interaction was not evident. Differences in physicochemical environment in the gut, availability, nature and amount of food supply are factors that most likely limit the distribution of parasites in different sections of the alimentary tract.Item The status and health burden of neurocysticercosis in Mbulu district, northern Tanzania(BioMed Central (BMC), 2018) Mwang'onde, Beda; Mwita, Chacha; Nkwengulila, GambaObjective: The objective of this study was to assess the extent and health burden of neurocysticercosis in the general community of the Mbulu district, northern Tanzania. About 1051 randomly select participants were screened for human cysticercosis. The Cysticercus Western Blot IgG and Computed Tomography scan were used to detect infection by cysticerci. The DALYs was used to assess the community’s health burden vis-a-vis neurocysticercosis. Results: The sero-prevalence of HCC was 16.27%. About 76% of 25 selected human cysticercosis sero-positives had neurocysticercosis suggestive lesions on CT scan and 74% had history of epilepsy. Epilepsy caused 2.8 years of life lost and 2.2 healthy years of life lost due to disability per 1000 person-years in Mbulu. The average DALYs imposed due to neurocysticercosis and epilepsy were 3.0 and 3.9 per 1000 person-years, respectively. Neurocysticercosis is a serious public health concern in northern Tanzania.Item Testing the performance of environmental DNA metabarcoding for surveying highly diverse tropical fish communities: A case study from Lake Tanganyika(John Wiley & Sons Ltd, 2019-10-02) Doble, Christopher; Hipperson, Helen; Salzburger, Walter; Horsburgh, Gavin; Mwita, Chacha; Murrell, David; Day, JuliaBackground and Aims: Environmental DNA (eDNA) metabarcoding provides a highly sensitive method of surveying freshwater fish communities, although studies to date have largely been restricted to temperate ecosystems. Due to limited reference sequence availability and challenges identifying closely related and rare species in diverse tropical ecosystems, the effectiveness of metabarcoding methods for surveying tropical fish communities from eDNA samples remains uncertain. To address this, we applied an eDNA metabarcoding approach to survey Lake Tanganyika's (LT) species‐rich littoral fish communities. Materials and Methods: As this system contains many closely related species, particularly cichlid fishes, we used four primer sets including a cichlid‐specific primer set (Cichlid_CR). A reference database was built for the 12s, 16s, and control region for 358 fish species including over 93% of known cichlids. Results and Discussion: In silico and in situ results demonstrated wide variability in the taxonomic resolution of assignments by each primer with the cichlid‐specific marker (Cichlid_CR) enabling greater species‐level assignments for this highly diverse family. A greater number of non‐cichlid teleost species were detected at sites compared to the visual survey data. For cichlid species however, sequencing depth substantially influenced species richness estimates obtained from eDNA samples, with increased depths producing estimates comparable to that obtained from the visual survey data. Conclusions: Our study highlights the importance of sequencing depth and local reference databases when undertaking metabarcoding studies within diverse ecosystems, as well as demonstrating the potential of eDNA metabarcoding for surveying diverse tropical fish communities, even those containing closely related species within evolutionary radiations.Item Validation of droplet digital Polymerase Chain Reaction for the detection and absolute quantification of Taenia solium eggs in spiked soil samples(Elsevier, 2019-09-14) Maganira, Justine; Mwang'onde, Beda; Kidima, Winifrida; Mwita, Chacha; Nkwengulila, Gamba; Hoglund, JohanTo enable the detection of taeniid eggs in environmental samples, a sensitive technology is required. In this study, we validated the effectiveness of a digital droplet Polymerase Chain Reaction (ddPCR) assay for detection, identification and absolute quantification of taeniid DNA from artificially contaminated soils with varying numbers of taeniid eggs using a set of universal primers, JB3 & JB4.5. The results showed that the number of cox1 copies detected increased gradually for both species with the number of taeniid eggs added to the different soil types. The highest cox1 DNA copies recovery for Taenia solium and T. lynciscapreoli was from the sand soil with lowest recovery being observed in clay soils. Therefore, ddPCR is a promising technology for screening of taeniid eggs from soil samples collected in the environment irrespective of the soil type and the number of eggs. The potential of the ddPCR protocol to detect taeniid egg DNA in spiked soil samples has great practical application for taeniid egg screening in soils from endemic areas. However, when universal primers are used in screening environmental samples, the identity of ddPCR positive samples must be confirmed by sequencing. In addition, more validation studies using species-specific primers and field soil samples is recommended.