Human African Trypanosomiasis and challenges to its control in Urambo, Kasulu and Kibondo Districts, western Tanzania

A study was carried out to determine the prevalence and management of Human African Trypanosomiasis (HAT) in Urambo, Kasulu and Kibondo districts of western Tanzania. Parasitological surveys for trypanosome and other blood parasites were conducted in selected villages. Interviews with health workers were conducted to explore facility capacity to diagnose and manage HAT. Community knowledge on tsetse and availability of trypanocidal drugs was explored. Results showed that, although health facility records showed HAT is an important public health problem in the three districts, typanosomes were found in 0.6% of the examined individuals in Urambo district only. Malaria parasites with a prevalence of 12.1%, 19.7% and 9.7%, in Urambo, Kibondo and Kasulu, respectively were detected in blood samples from the same individuals examined for trypanosomes. There was poor capacity for most of the health facilities in the diagnosis, treatment and control of HAT. In both districts, communities were knowledgeable of the tsetse identity (82.4%) and had experienced tsetse bites (94%). The majority (91.4%) of the community members knew that they were at risk of acquiring HAT. However, only 29% of the respondents knew that anti-trypanocidal drugs were readily available free of charge from health care facilities. Late treatment seeking behaviour was common in Kasulu and Urambo districts. In conclusion, health facilities in western Tanzania are faced with problems of poor capacity to diagnose and manage HAT and that treatment seeking behaviour among the communities at risk is poor. Efforts should be made to strengthen the capacity of the health facility to handle HAT cases and health education to the population at risk. Keywords: Human African Trypanosomiasis, diagnosis, control, TanzaniaTanzania Health Research Bulletin Vol. 8 (2) 2006: pp. 80-8

Comparative studies on the structure of an upland African stream ecosystem

Upland stream systems have been extensively investigated in Europe, North America and Australasia and many of the central ideas concerning their function are based on these systems. One central paradigm, the river continuum concept is ultimately derived from those North American streams whose catchments remain forested with native vegetation. Streams of the tropics may or may not fit the model. They have been little studied. The Amani Nature Reserve in the East Usambara Mountains of north-eastern Tanzania offers an opportunity to bring these naturally forested systems to the attention of the ecological community. This article describes a comparison made between two lengths of the River Dodwe in this area. The work was carried out by a group of postgraduate students from eighteen European and African countries with advice from five staff members, as part of a course organised by the Tropical Biology Association. Rigorous efforts were made to standardise techniques, in a situation where equipment and laboratory facilities were very basic, through a management structure and deliberate allocation of work to specialists in each area.The article offers a summary of invertebrate communities found in the stream and its biomass. Crabs seem to be the key organism in both sections of the streams

Incorporating scale dependence in disease burden estimates:the case of human African trypanosomiasis in Uganda

The WHO has established the disability-adjusted life year (DALY) as a metric for measuring the burden of human disease and injury globally. However, most DALY estimates have been calculated as national totals. We mapped spatial variation in the burden of human African trypanosomiasis (HAT) in Uganda for the years 2000-2009. This represents the first geographically delimited estimation of HAT disease burden at the sub-country scale.Disability-adjusted life-year (DALY) totals for HAT were estimated based on modelled age and mortality distributions, mapped using Geographic Information Systems (GIS) software, and summarised by parish and district. While the national total burden of HAT is low relative to other conditions, high-impact districts in Uganda had DALY rates comparable to the national burden rates for major infectious diseases. The calculated average national DALY rate for 2000-2009 was 486.3 DALYs/100 000 persons/year, whereas three districts afflicted by rhodesiense HAT in southeastern Uganda had burden rates above 5000 DALYs/100 000 persons/year, comparable to national GBD 2004 average burden rates for malaria and HIV/AIDS.These results provide updated and improved estimates of HAT burden across Uganda, taking into account sensitivity to under-reporting. Our results highlight the critical importance of spatial scale in disease burden analyses. National aggregations of disease burden have resulted in an implied bias against highly focal diseases for which geographically targeted interventions may be feasible and cost-effective. This has significant implications for the use of DALY estimates to prioritize disease interventions and inform cost-benefit analyses

Comparative studies on the structure of an upland African stream ecosystem

Upland stream systems have been extensively investigated in Europe,North America and Australasia and many of the central ideas concerningtheir function are based on these systems. One central paradigm, the rivercontinuum concept (Vannote et al. 1980) is ultimately derived from thoseNorth American streams whose catchments remain forested with nativevegetation

Predominant Leptospiral Serogroups circulating among humans, livestock and wildlife in Katavi-Rukwa ecosystem, Tanzania

PLOS Neglected Tropical Diseases March 25, 2015Background: Leptospirosis is a worldwide zoonotic disease and a serious, under-reported public health problem, particularly in rural areas of Tanzania. In the Katavi-Rukwa ecosystem, humans, livestock and wildlife live in close proximity, which exposes them to the risk of a number of zoonotic infectious diseases, including leptospirosis. Methodology/Principal Findings: A cross-sectional epidemiological study was carried out in the Katavi region, South-west Tanzania, to determine the seroprevalence of Leptospira spp in humans, domestic rumi- nants and wildlife. Blood samples were collected from humans (n = 267), cattle (n = 1,103), goats (n = 248), buffaloes (n = 38), zebra (n = 2), lions (n = 2), rodents (n = 207) and shrews (n = 11). Decanted sera were tested using the Microscopic Agglutination Test (MAT) for an- tibodies against six live serogroups belonging to the Leptospira spp , with a cutoff point of 1:160. The prevalence of leptospiral antibodies was 29.96% in humans, 30.37% in cattle, 8.47% in goats, 28.95% in buffaloes, 20.29% in rodents and 9.09% in shrews. Additionally, one of the two samples in lions was seropositive. A significant difference in the prevalence P < 0.05 was observed between cattle and goats. No significant difference in prevalence was observed with respect to age and sex in humans or any of the sampled animal species. The most prevalent serogroups with antibodies of Leptospira spp were Sejroe, Hebdoma- dis, Grippotyphosa, Icterohaemorrhagie and Australis, which were detected in humans, cattle, goats and buffaloes; Sejroe and Grippotyphosa, which were detected in a lion; Aus- tralis, Icterohaemorrhagie and Grippotyphosa, which were detected in rodents; and Austra- lis, which was detected in shrews. Antibodies to serogroup Ballum were detected only in humans. Conclusions: The results of this study demonstrate that leptospiral antibodies are widely prevalent in hu- mans, livestock and wildlife from the Katavi-Rukwa ecosystem. The disease poses a seri- ous economic and public health threat in the study area. This epidemiological study provides information on circulating serogroups, which will be essential in designing inter- vention measures to reduce the risk of disease transmission