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Trypanosomes transmitted by mosquitoes: occurrence in hosts, transmission, and specificity
Kulich Fialová, Magdaléna ; Svobodová, Milena (advisor) ; Bernotienė, Rasa (referee) ; Modrý, David (referee)
7 Abstract Trypanosomes (Trypanosoma, Kinetoplastea) are dixenous blood protists that require not only a vertebrate host but also a blood-feeding invertebrate to complete their life cycle. Infection of vertebrates can be asymptomatic, but on the other hand can cause serious diseases affecting lives of humans and animals. Thus, researchers usually focus on Trypanosoma species causing Chagas disease and sleeping sickness in humans or nagana and surra in animals, and on their vectors: tsetse flies and kissing bugs. However, mosquitoes are able to transmit trypanosomes as well, specifically, avian trypanosomes and probably mammalian trypanosomes from the T. theileri group. Nevertheless, the role of mosquitoes in the life cycle of trypanosomes has substantial gaps, which are focused in this dissertation. Within the experimental work, it has been demonstrated that mosquitoes of the genus Culex are susceptible hosts of two species of avian trypanosomes: T. thomasbancrofti and T. tertium n. sp. On the other hand, Culex mosquitoes were unsuitable hosts for T. theileri, while the genus Aedes and surprisingly even sand flies (Phlebotomus perniciosus) turned up to be competent vectors. All investigated trypanosomes were able to develop within the guts of mosquitoes and were also found in their prediuretic liquid. This...
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Prevalence and risk factors of malaria among children under 5 years and the prevention and treatment regimens in the Kitase community of Ghana
Amponsah, Ebo Owusu
The purpose of this study was to investigate the incidence of malaria in children under the age of five living in the Kitase Community in Ghana, as well as possible causes, preventative measures, and therapeutic approaches. The principal goals of the research were accomplished through the use of a hospital-based cross-section design, which required the gathering of primary data from women living in the Kitase township, which is located within the Akuapim South Municipal Assembly in Ghana. For the analysis, we utilised version 16 of the STATA statistical software. The chi-squared test and logistic regression were performed to determine the relationship between malaria incidence and household and environmental characteristics. Findings showed that malaria prevalence among under 5 children was 19.62% with a total of 46.15% with at least occurrence of malaria illness in the past three months. Also, ownership of Long-Lasting Insecticidal Nets (LLINs) was 77.31%, and its use among 58.46% of mothers. However, Environmental characteristics such as bushes, waste dumpsites, stagnant water, and breeding areas around the house increase the odds of malaria infection by AOR of 1.885, 2.455, 2.197, and 2.060, respectively. Therefore, the study recommends that health authorities in the study area ensure the proper usage of LLINs (mosquito nets) through regular and effective education on preventive measures and ensure that good sanitation is observed in settlements.
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Trypanosomes from the T. theileri group in ungulates in the Czech Republic
Brotánková, Anna ; Brzoňová, Jana (advisor) ; Juránková, Jana (referee)
The Trypanosoma theileri group are blood parasites of ungulates. Confirmed vectors of these protists are horseflies or sheep keds for T. melophagium, but these trypanosomes were also detected in deer keds, mosquitoes and phlebotomus. We targeted on the investigation of possibility mosquitoes acting as vectors and additionally we targeted on the prevalence of T. theileri in mosquitoes at selected locations in the Czech Republic due to previous positive detection there. The measured prevalence has reached 6,4 % in mosquitoes, 4 % in deer keds and 16,7 % in sheep keds. The aim of experimental infections was to discover a potential of mosquitoes and phlebotomus acting as vectors of the T. theileri. Phlebotomus perniciosus and three species of mosquitoes Culex pipiens molestus, Culex pipiens quinquefasciatus and Aedes vexans were used for those experiments. Furthermore, isolates of T. theileri and T. melophagium from different sources were used. The divergence among these isolates and among used species of insect was found. The best results were achieved with Ae. aegypti and isolates from mosquitoes, where prevalence had reached 90,8 %. The infected mosquitoes were used for prediuresis research which had shown infection forms of the trypanosomes in the urine liquid. The phylogenetic analyse of T....
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Trypanosomes from the T. theileri group in ungulates in the Czech Republic
Brotánková, Anna ; Brzoňová, Jana (advisor) ; Juránková, Jana (referee)
The Trypanosoma theileri group are blood parasites of ungulates. Confirmed vectors of these protists are horseflies or sheep keds for T. melophagium, but these trypanosomes were also detected in deer keds, mosquitoes and phlebotomus. We targeted on the investigation of possibility mosquitoes acting as vectors and additionally we targeted on the prevalence of T. theileri in mosquitoes at selected locations in the Czech Republic due to previous positive detection there. The measured prevalence has reached 6,4 % in mosquitoes, 4 % in deer keds and 16,7 % in sheep keds. The aim of experimental infections was to discover a potential of mosquitoes and phlebotomus acting as vectors of the T. theileri. Phlebotomus perniciosus and three species of mosquitoes Culex pipiens molestus, Culex pipiens quinquefasciatus and Aedes vexans were used for those experiments. Furthermore, isolates of T. theileri and T. melophagium from different sources were used. The divergence among these isolates and among used species of insect was found. The best results were achieved with Ae. aegypti and isolates from mosquitoes, where prevalence had reached 90,8 %. The infected mosquitoes were used for prediuresis research which had shown infection forms of the trypanosomes in the urine liquid. The phylogenetic analyse of T....
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Indukce autogenie biologicky aktivními látkami u druhu \kur{Culex quinquefasciatus Say}
ŠEFČÍK, David
The main aim of this study was determinate which factors could induce autogeny and compare differences between autogenous and anautogenous populations of mosquitoes. All experiments were done with \kur{Culex quinquefasciatus Say}. Effects on temperature and food on the inductuion of autogeny were studied. Autogenous females usually don´t have to receive a blood during the first ovarian cycle. Our results confirmed that autogeny can be induced by temperature and different food high nutritive level.
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Mosquitoes as hosts and vectors of protozoa transmitted to birds
Fialová, Magdaléna ; Svobodová, Milena (advisor) ; Munclinger, Pavel (referee)
Mosquitoes belong to significant representatives of inscet which are particularly studied due to their ability to transmit pathogens (viruses, bacteria, protozoa, worms) in many cases causing serious illnesses. The hosts of these pathogens can be various animals including birds. In this study I have focused on protozoa (especially Plasmodium and Trypanosoma) transmitted by a mosquito. Concerning trypanosomes the mosquito is one of several possible vectors and up to now there have been named two trypanosomes transmitted by birds, namely Trypanosoma culicavium and Trypanosoma thomasbancrofti. In the case of the genus Plasmodium the mosquito is the only vector and there are many more species of the genus Plasmodium, which mosquito transmits between birds. Key words: vector, mosquito, host, bird, Trypanosoma, Plasmodium, infection
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Differences of autogeny and anautogeny population of mosquitoes Culex pipiens quinquefasciatus Say
DIVOKÁ, Petra
The aim of submited Thesis was to contribute to illustration on differences in development of female genital organs in autogeny and anautogeny population of mosquito Culex pipiens quinquefasciatus Say. Currently, a consequence of ekdyson agonists was tested for change evoked in the development and fertility this species. Gained results showed that in anautogeny population is process of vitellogenesis depended on blood- feeding. In autogeny population, there is no need to blood- fed during the first gonotrophic cycle. Tested compound indicated vitellogenesis in a sublethal doses then egg-laying was followed. In comparison with that, application of higher doses showed sterilisation effect. Gained results show this compound useful for regulation of mosquitoes population, especially in the area of disease transmitted by them.
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Histological and histochemical methods used in study of development of internal male sex organs
VÁVROVÁ, Martina
Presented thesis devotes to comparative study of usability of fixation agents and colouring methods for the study of histology and histochemistry of Culex pipiens s.l. mosquito males. The study was carried out in males of Culex pipiens quinquefasciatus Say, which is a significant transmitter of filariasis. Histological and histochemistry studies of the structure of the whole abdomens or prepared testicles were carried out on the material fixed by fixation agents Carnoy and Bouin of Dubosque-Brasil modification. Fixed tissue was cast in paraplast or resin. Histological sections were done by means of automatic microtome Leica and half-thin sections by means of ultra microtone Reichert. Section preparations were coloured by Mayer or Harris haematoxylin or by colouring method according to Mallory. Semi-thin sections from materials cast in resin were coloured by toluidine blue. Fixation agent Bouin, Dubosque-Brasil modification proved as more convenient than Carnoy, either for the preparation of paraffin sections or for fabrication of half-thin sections from tissues cast in resin. The next advantage of this fixation is that fixed tissue can be stored for unlimited period of time without over fixation of the tissue as it is in the case of fixation by Carnoy. For general histological preparations Mallory colouring is apparently the most convenient from the used methods; it provides better orientation in coloured tissue thanks to the whole spectrum of colours-pink to red colouring of cell nuclei, blue colouring of tissue and secretions. In case of colouring of male genital organs all used colourings (Mallory, Harris and Mayer haematoxylin) seem to be comparable. Casting in resin with connection to colouring by toluidine blue (also histochemistry proof for carbohydrates) has shown to be suitable for visualisation of finer structures, in male genital organs particular developmental phases of male sex cells were distinguished.
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