Presentation of Trypanosomiasis in Nkhotakota

In 2002, we identified 28 people in Nkhotakota District who were suffering from Human African Trypanosomiasis (HAT). Sixteen of these were identified when they presented to the District Hospital with a febrile illness. The remaining twelve were identified through a rural cross-sectional survey, in which 500 people were visited in their homes, persons found to be febrile, were examined by blood film microscopy. Of the 28 people, 50% (14) presented within a month of the onset of symptoms. Sixteen (57%) had splenomegaly, and 24 were anaemic ([Hb

Role of Cytokines in Trypanosoma brucei-Induced Anaemia: A Review of the Literature

Background: Anaemia is an important complication of trypanosomiasis. The mechanisms through which trypanosomal infection leads to anaemia are poorly defined. A number of studies have implicated inflammatory cytokines, but these data are limited and inconsistent. In this article, we reviewed the published literature on cytokines associated with Trypanosoma brucei infections and their role in the immunopathology leading to anaemia.Methodology: Articles were searched in PubMed through screening of titles and abstracts with no limitation on date of publishing and study design. Articles in English were searched using keywords “African trypanosomiasis”, “sleeping sickness”, “Trypanosoma brucei”, in all possible combinations with “anaemia” and/or “cytokines”.Results: Twelve articles examining cytokines and their role in trypanosomeinduced anaemia were identified out of 1095 originally retrieved from PubMed. None of the articles identified were from human-based studies. A total of eight cytokines were implicated, with four cytokines (IFN-γ, IL-10, TNF-α, IL-12) showing an association with anaemia. These articles reported that mice lacking TNF-α were able to control anaemia, and that IFN-γ was linked to severe anaemia given its capacity to suppress erythropoiesis, while IL-10 was shown to regulate IFN-γ and TNF-α, providing a balance that was associated with severity of anaemia. IFN-γ and TNF-α have also been reported to work in concert with other factors such as nitric oxide and iron in order to induce anaemia.Conclusion: IFN-γ, IL-10, and TNF-α were the three major cytokines identified to beheavily involved in anaemia caused by Trypanosoma brucei infection. The anti-inflammatory cytokine, IL-10, was shown to counter the effects of proinflammatory cytokines in order to balance the severity of anaemia. The mechanism of anaemia is multifactorial and therefore requires further, more elaborate research. Data from human subjects would also shed more light

Oesophageal cancer and Kaposi’s Sarcoma in Malawi: a comparative analysis

Given that oesophageal cancer (OC) is common in Malawi and its outcome is so dismal, would it be pragmatic to promptly mitigate the effects of smoking, alcohol and aflatoxins rather than seek a higher degree of local evidencefor their role in OC? We retrospectively analysed a total of 13,217 OC andKaposi’s sarcoma (KS) cases as recorded in the Malawi National Cancer Registry from 1985 to February, 2006. We found no OC clustering to suggest a role for culturally variable habits like smoking, alcohol, maize use and maize storage in the country. It may be that drinking and eating hotfoods physically damages the oesophageal mucosa, this is in line with work recently reported from Asia. We also found that OC numbers have risen in line with KS (and HIV) suggesting a link between these conditions

Environmental risk factors for oesophageal cancer in Malawi: A case-control study

Aim There is a high burden of oesophageal cancer in Malawi with dismal outcomes. It is not known whether environmental factors are associated with oesophageal cancer. Without knowing this critical information, prevention interventions are not possible. The purpose of this analysis was to explore environmental factors associated with oesophageal cancer in the Malawian context.Methods A hospital-based case-control study of the association between environmental risk factors and oesophageal cancer was conducted at Kamuzu Central Hospital in Lilongwe, Malawi and Queen Elizabeth Central Hospital in Blantyre, Malawi. Ninety-six persons with squamous cell carcinoma and 180 controls were enrolled and analyzed. These two groups were compared for a range of environmental risk factors, using logistic regression models. Unadjusted and adjusted odds ratios and 95% confidence intervals (CI) were calculated.Results Firewood cooking, cigarette smoking, and use of white maize flour all had strong associations with squamous cell carcinoma of the oesophagus, with adjusted odds ratios of 12.6 (95% CI: 4.2-37.7), 5.4 (95% CI: 2.0-15.2) and 6.6 (95% CI: 2.3-19.3), respectively.Conclusions Several modifiable risk factors were found to be strongly associated with squamous cell carcinoma. Research is needed to confirm these associations and then determine how to intervene on these modifiable risk factors in the Malawian context

Environmental risk factors for oesophageal cancer in Malawi: A case-control study

There is a high burden of oesophageal cancer in Malawi with dismal outcomes. It is not known whether environmental factors are associated with oesophageal cancer. Without knowing this critical information, prevention interventions are not possible. The purpose of this analysis was to explore environmental factors associated with oesophageal cancer in the Malawian context

<i>Trypanosoma brucei rhodesiense</i> transmitted by a single tsetse fly bite in vervet monkeys as a model of human African trypanosomiasis

Sleeping sickness is caused by a species of trypanosome blood parasite that is transmitted by tsetse flies. To understand better how infection with this parasite leads to disease, we provide here the most detailed description yet of the course of infection and disease onset in vervet monkeys. One infected tsetse fly was allowed to feed on each host individual, and in all cases infections were successful. The characteristics of infection and disease were similar in all hosts, but the rate of progression varied considerably. Parasites were first detected in the blood 4-10 days after infection, showing that migration of parasites from the site of fly bite was very rapid. Anaemia was a key feature of disease, with a reduction in the numbers and average size of red blood cells and associated decline in numbers of platelets and white blood cells. One to six weeks after infection, parasites were observed in the cerebrospinal fluid (CSF), indicating that they had moved from the blood into the brain; this was associated with a white cell infiltration. This study shows that fly-transmitted infection in vervets accurately mimics human disease and provides a robust model to understand better how sleeping sickness develops

The epidemiology of trypanosomiasis in Rumphi district, Malawi: a ten year retrospective study

Background Human African Trypanosomiasis (HAT) is caused by two species of the tsetse fly vectored protozoan hemoflagellates belonging to Trypanosma brucei, namely T.b gambiense which predominates in Western Africa and follows a chronic disease course and T.b rhodensiense which is more prevalent in Southern and Eastern Africa, Malawi included, and follows a more acute and aggressive disease course. Previous studies in the Democratic Republic of Congo, Angola, Uganda and Sudan have demonstrated that the prevalence rates of T.b rhodensiense infection have reached epidemic proportions. Objectives To describe the epidemiology of Trypanosomiasis in Rumphi District over the past ten years. Methodology A total of 163 records from January 2000 to December 2006 were retrospectively studied. Results There were more males than females (121 vs. 40) with the 20 – 29 years age bracket having the highest number of cases (26.3%, n=160). Stage 2 HAT was the commonest stage at presentation (58.2%, n=158) with the patients in the same being 3.5 times more likely to die than those with stage 1 HAT. Case fatality rates for late and early stage disease were 21.5% (n = 92) and 7.2% (n = 66) respectively with 84.6% having been cured (n=162). Convulsions were associated with fatal disease outcome and the majority of cases (97.2%, n=103) lived within 5 kilometres of the Vwaza game reserve boundary. Conclusion More men have been infected than women, with a high involvement in the 20 – 29 age brackets. A dramatic increase with active case finding indicates a high under-detection of the disease with late stage HAT being predominant at presentation. Though it has been found that cases with late stage disease have an increased likelihood of dying compared to those in early stage HAT, the high proportion of successful treatment indicates that the disease still carries a high degree of favourable outcome with treatment. It has also been demonstrated in this study that more than 95% of trypanosomiasis cases live within 5 km of game reserve boundary. Disease interventions should be implemented in areas within 5km of marshland game reserve boundary as priority areas. Malawi Medical Journal Vol. 21 (1) 2009: pp. 22-2

Presentation of Trypanosomiasis in Nkhotakota

In 2002, we identified 28 people in Nkhotakota District who were suffering from Human African Trypanosomiasis (HAT). Sixteen of these were identified when they presented to the District Hospital with a febrile illness. The remaining twelve were identified through a rural cross-sectional survey, in which 500 people were visited in their homes, persons found to be febrile, were examined by blood film microscopy. Of the 28 people, 50% (14) presented within a month of the onset of symptoms. Sixteen (57%) had splenomegaly, and 24 were anaemic ([Hb] <12 g/dl). Four patients died (14%), of which two were in the late stage of the disease. None of the patients recall having a chancre that could be attributed to the bite of tsetse flies. 9 out of 28 (32%) reported illness longer than 90 days. Of the 9 patients 6 (66%) of them remained in the early stage after reporting illness of 180 days. This study reports on the prevalence and clinical features of Trypanosoma brucei rhodesiense infection in a endemic district in Malawi