Table S2. Species diversity and relative abundance (%) of Culicoides collected with OVI traps fro... more Table S2. Species diversity and relative abundance (%) of Culicoides collected with OVI traps from 2007 to 2011 at 7 sites in Belgium). (DOCX 28 kb)
Identification of different trypanosome species in Conclusion: The presence of Trypanosoma brucei... more Identification of different trypanosome species in Conclusion: The presence of Trypanosoma brucei in tsetse mid-guts associated with human blood meals is
Table S1. Location, sampling period, local ecological factors in the immediate vicinity of the co... more Table S1. Location, sampling period, local ecological factors in the immediate vicinity of the collection site and eco-region with its characteristic ecological aspects for all 7 collection sites. (DOCX 14 kb)
To identify possible vectors of Schmallenberg virus (SBV), we tested pools containing heads of bi... more To identify possible vectors of Schmallenberg virus (SBV), we tested pools containing heads of biting midges (Culicoides) that were caught during the summer and early autumn of 2011 at several places in Belgium by real time RT-PCR. Pools of heads originating from following species: C. obsoletus complex, C. dewulfi and C. chiopterus were found positive, strongly indicating that these species are relevant vectors for SBV.
During the past decades the publication of papers interest related to the use of geographical inf... more During the past decades the publication of papers interest related to the use of geographical information systems (GIS) and/or remote sensing (RS) and of particular interest to veterinary parasitology veterinary followed an exponential trend. The use of GIS and RS is now generally accepted by the scientific community as a major tool contributing to the understanding of epidemiological processes sensu lato: disease –vector –host –environment. Nevertheless, whilst most people now are aware of the potential of these techniques, many still hesitate to use these tools for research or decision making. This paper reviews recent advances towards more widespread ‘routine’ use of GIS and RS in parasitology. After a brief introduction setting historical trends and milestones, followed by a more detailed review of past work in three chosen fields, tsetse transmitted trypanosomosis, liver fluke and East Coast fever, the authors discuss how Geographical Information Systems-Science (GIS) is curren...
INTRODUCTION A variety of techniques have been used to control tsetse with varying degrees of suc... more INTRODUCTION A variety of techniques have been used to control tsetse with varying degrees of success. In a study on the population structure of Glossina fuscipes fuscipes that recovered after a previous vector control trial on 2 Kenyan islands, it was reported that the average fly size on the intervention islands was significantly smaller than on the none intervention islands and also compared to the size before the intervention. The conclusion was that vector control using tiny targets exerted size selection pressure on the population. The study recommended for further studies and suggested that this phenomenon could be among the reasons why targets used as a sole control method have rare reports of successful elimination of tsetse populations. Therefore, in this paper we report on a study of body size of tsetse flies caught in epsilon traps (as a stationary device) and black screen fly rounds (as a mobile trapping device). MATERIALS AND METHODS The study was carried out in eastern Zambia to test the hypothesis that the body size (measured as wing length) of G. m. morsitans males or females, captured by epsilon traps and fly rounds is the same. RESULTS A total of 1,442 (489 females and 953 males) wing length measurements of G. m. morsitans were used in the analysis. It was established that tsetse flies caught by epsilon traps are on average larger than those caught by fly rounds. The likelihood of a large female or male fly being caught by traps, relative to a small one, significantly increased by 5.088 times (95% CI: 3.138-8.429) and by 2.563 times (95% CI: 1.584-4.148), respectively, p<0.0001, compared with being caught by fly rounds. The hypothesis was rejected. CONCLUSION This study showed that epsilon traps capture significantly larger G. m. morsitans than fly rounds do. Therefore, further research is recommended to verify (i) whether the predilection of traps to capture larger flies has an effect on the process of tsetse elimination when targets are used e.g. targets may take longer to reach elimination than if the predilection was not there, ii) whether different results can be obtained on ecogeographic distribution of different sizes of the species if fly rounds are used for sampling instead of epsilon traps. The results from such studies could influence the strategies used in future control operations.
Naive Beagle dogs (n = 5) were experimentally inoculated with two stocks of Babesia canis. Dogs w... more Naive Beagle dogs (n = 5) were experimentally inoculated with two stocks of Babesia canis. Dogs were examined regularly for parasitaemia and for antibodies, using the indirect immunofluorescent antibody test (IFAT). This test proved to be useful for the diagnosis of babesiosis. After primo-infection dogs seem to develop a certain degree of immunity, although this immunity is neither absolute nor of long duration. Treatment of infected dogs with imidocarb (6 mg/kg) cleared the infection, but did not prevent the production of IFAT-antibodies. An infected dog treated with long acting oxytetracycline (20 mg/kg) became a subclinical, chronic carrier of the disease.
Fragmentation of tsetse habitat in eastern Zambia is largely due to encroachments by subsistence ... more Fragmentation of tsetse habitat in eastern Zambia is largely due to encroachments by subsistence farmers into new areas in search of new agricultural land. The impact of habitat fragmentation on tsetse populations is not clearly understood. This study was aimed at establishing the impact of habitat fragmentation on physiological and demographic parameters of tsetse flies in order to enhance the understanding of the relationship between fragmentation and African animal trypanosomosis (AAT) risk. A longitudinal study was conducted to establish the age structure, abundance, proportion of females and trypanosome infection rate of Glossina morsitans morsitans Westwood (Diptera: Glossinidae) in areas of varying degrees of habitat fragmentation in Eastern Zambia. Black screen fly rounds were used to sample tsetse populations monthly for 1 year. Logistic regression was used to analyse age, proportion of females and infection rate data. Flies got significantly older as fragmentation increase...
In an effort to understand better the transmission risk as well for the animal African trypanosom... more In an effort to understand better the transmission risk as well for the animal African trypanosomosis (AAT) as for the human trypanosomosis (HAT) in the peri-urban zone of Kinshasa, a serologic study was carried out in local pig farms from 2003 to 2005. An indirect ELISA was used to detect the presence of trypanosome antibodies in 1,240 pigs originating from 404 farms. Seropositivity was recorded in 155 farms (38%), but varied considerably according to the district. In 6% of the farms TAA could be confirmed by parasitological examination. Trapping sites (n = 367) established in the neighbourhood of pig farms made it possible to capture 1,935 tsetse flies (Glossina fuscipes quanzensis). Among 562 dissected flies 23 were found to harbour trypanosomes resulting in an infection rate of 4.1%. In the majority of the districts the transmission risk for animal trypanosomosis anticipated from the apparent vector densities was corroborated by the serology. Zones with strong indications of loc...
Tsetse-transmitted human or livestock trypanosomiasis is one of the major constraints to rural de... more Tsetse-transmitted human or livestock trypanosomiasis is one of the major constraints to rural development in sub-Saharan Africa. The epidemiology of the disease is determined largely by tsetse fly density. A major factor, contributing to tsetse population density is the availability of suitable habitat. In large parts of Africa, encroachment of people and their livestock resulted in a destruction and fragmentation of such suitable habitat. To determine the effect of habitat change on tsetse density a study was initiated in a tsetse-infested zone of eastern Zambia. The study area represents a gradient of habitat change, starting from a zone with high levels of habitat destruction and ending in an area where livestock and people are almost absent. To determine the distribution and density of the fly, tsetse surveys were conducted throughout the study area in the dry and in the rainy season. Landsat ETM+ imagery covering the study area were classified into four land cover classes (mun...
Table S2. Species diversity and relative abundance (%) of Culicoides collected with OVI traps fro... more Table S2. Species diversity and relative abundance (%) of Culicoides collected with OVI traps from 2007 to 2011 at 7 sites in Belgium). (DOCX 28 kb)
Identification of different trypanosome species in Conclusion: The presence of Trypanosoma brucei... more Identification of different trypanosome species in Conclusion: The presence of Trypanosoma brucei in tsetse mid-guts associated with human blood meals is
Table S1. Location, sampling period, local ecological factors in the immediate vicinity of the co... more Table S1. Location, sampling period, local ecological factors in the immediate vicinity of the collection site and eco-region with its characteristic ecological aspects for all 7 collection sites. (DOCX 14 kb)
To identify possible vectors of Schmallenberg virus (SBV), we tested pools containing heads of bi... more To identify possible vectors of Schmallenberg virus (SBV), we tested pools containing heads of biting midges (Culicoides) that were caught during the summer and early autumn of 2011 at several places in Belgium by real time RT-PCR. Pools of heads originating from following species: C. obsoletus complex, C. dewulfi and C. chiopterus were found positive, strongly indicating that these species are relevant vectors for SBV.
During the past decades the publication of papers interest related to the use of geographical inf... more During the past decades the publication of papers interest related to the use of geographical information systems (GIS) and/or remote sensing (RS) and of particular interest to veterinary parasitology veterinary followed an exponential trend. The use of GIS and RS is now generally accepted by the scientific community as a major tool contributing to the understanding of epidemiological processes sensu lato: disease –vector –host –environment. Nevertheless, whilst most people now are aware of the potential of these techniques, many still hesitate to use these tools for research or decision making. This paper reviews recent advances towards more widespread ‘routine’ use of GIS and RS in parasitology. After a brief introduction setting historical trends and milestones, followed by a more detailed review of past work in three chosen fields, tsetse transmitted trypanosomosis, liver fluke and East Coast fever, the authors discuss how Geographical Information Systems-Science (GIS) is curren...
INTRODUCTION A variety of techniques have been used to control tsetse with varying degrees of suc... more INTRODUCTION A variety of techniques have been used to control tsetse with varying degrees of success. In a study on the population structure of Glossina fuscipes fuscipes that recovered after a previous vector control trial on 2 Kenyan islands, it was reported that the average fly size on the intervention islands was significantly smaller than on the none intervention islands and also compared to the size before the intervention. The conclusion was that vector control using tiny targets exerted size selection pressure on the population. The study recommended for further studies and suggested that this phenomenon could be among the reasons why targets used as a sole control method have rare reports of successful elimination of tsetse populations. Therefore, in this paper we report on a study of body size of tsetse flies caught in epsilon traps (as a stationary device) and black screen fly rounds (as a mobile trapping device). MATERIALS AND METHODS The study was carried out in eastern Zambia to test the hypothesis that the body size (measured as wing length) of G. m. morsitans males or females, captured by epsilon traps and fly rounds is the same. RESULTS A total of 1,442 (489 females and 953 males) wing length measurements of G. m. morsitans were used in the analysis. It was established that tsetse flies caught by epsilon traps are on average larger than those caught by fly rounds. The likelihood of a large female or male fly being caught by traps, relative to a small one, significantly increased by 5.088 times (95% CI: 3.138-8.429) and by 2.563 times (95% CI: 1.584-4.148), respectively, p<0.0001, compared with being caught by fly rounds. The hypothesis was rejected. CONCLUSION This study showed that epsilon traps capture significantly larger G. m. morsitans than fly rounds do. Therefore, further research is recommended to verify (i) whether the predilection of traps to capture larger flies has an effect on the process of tsetse elimination when targets are used e.g. targets may take longer to reach elimination than if the predilection was not there, ii) whether different results can be obtained on ecogeographic distribution of different sizes of the species if fly rounds are used for sampling instead of epsilon traps. The results from such studies could influence the strategies used in future control operations.
Naive Beagle dogs (n = 5) were experimentally inoculated with two stocks of Babesia canis. Dogs w... more Naive Beagle dogs (n = 5) were experimentally inoculated with two stocks of Babesia canis. Dogs were examined regularly for parasitaemia and for antibodies, using the indirect immunofluorescent antibody test (IFAT). This test proved to be useful for the diagnosis of babesiosis. After primo-infection dogs seem to develop a certain degree of immunity, although this immunity is neither absolute nor of long duration. Treatment of infected dogs with imidocarb (6 mg/kg) cleared the infection, but did not prevent the production of IFAT-antibodies. An infected dog treated with long acting oxytetracycline (20 mg/kg) became a subclinical, chronic carrier of the disease.
Fragmentation of tsetse habitat in eastern Zambia is largely due to encroachments by subsistence ... more Fragmentation of tsetse habitat in eastern Zambia is largely due to encroachments by subsistence farmers into new areas in search of new agricultural land. The impact of habitat fragmentation on tsetse populations is not clearly understood. This study was aimed at establishing the impact of habitat fragmentation on physiological and demographic parameters of tsetse flies in order to enhance the understanding of the relationship between fragmentation and African animal trypanosomosis (AAT) risk. A longitudinal study was conducted to establish the age structure, abundance, proportion of females and trypanosome infection rate of Glossina morsitans morsitans Westwood (Diptera: Glossinidae) in areas of varying degrees of habitat fragmentation in Eastern Zambia. Black screen fly rounds were used to sample tsetse populations monthly for 1 year. Logistic regression was used to analyse age, proportion of females and infection rate data. Flies got significantly older as fragmentation increase...
In an effort to understand better the transmission risk as well for the animal African trypanosom... more In an effort to understand better the transmission risk as well for the animal African trypanosomosis (AAT) as for the human trypanosomosis (HAT) in the peri-urban zone of Kinshasa, a serologic study was carried out in local pig farms from 2003 to 2005. An indirect ELISA was used to detect the presence of trypanosome antibodies in 1,240 pigs originating from 404 farms. Seropositivity was recorded in 155 farms (38%), but varied considerably according to the district. In 6% of the farms TAA could be confirmed by parasitological examination. Trapping sites (n = 367) established in the neighbourhood of pig farms made it possible to capture 1,935 tsetse flies (Glossina fuscipes quanzensis). Among 562 dissected flies 23 were found to harbour trypanosomes resulting in an infection rate of 4.1%. In the majority of the districts the transmission risk for animal trypanosomosis anticipated from the apparent vector densities was corroborated by the serology. Zones with strong indications of loc...
Tsetse-transmitted human or livestock trypanosomiasis is one of the major constraints to rural de... more Tsetse-transmitted human or livestock trypanosomiasis is one of the major constraints to rural development in sub-Saharan Africa. The epidemiology of the disease is determined largely by tsetse fly density. A major factor, contributing to tsetse population density is the availability of suitable habitat. In large parts of Africa, encroachment of people and their livestock resulted in a destruction and fragmentation of such suitable habitat. To determine the effect of habitat change on tsetse density a study was initiated in a tsetse-infested zone of eastern Zambia. The study area represents a gradient of habitat change, starting from a zone with high levels of habitat destruction and ending in an area where livestock and people are almost absent. To determine the distribution and density of the fly, tsetse surveys were conducted throughout the study area in the dry and in the rainy season. Landsat ETM+ imagery covering the study area were classified into four land cover classes (mun...
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