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Copper levels in three commonly edible fruits: Are consumers at risk?
(JOURNAL OF AGRICULTURE AND APPLIED BIOLOGY, 2021) Minati, Sahu; Kacholi, David Sylvester
This study aimed to investigate levels of copper in three commonly edible fruits, namely, Lycopersicon esculenta (tomato), Citrullus la-natus (watermelon) and Cucumis sativus (cucumber) traded in Dar es Salaam city. Also, the study scrutinized risk associated with heavy metal intake in the fruits. The fruits were collected from Buguruni Market, one of the biggest markets in the city, and thereafter, were processed, and analyzed to determine copper levels. The average daily intake and human health risk indices were calculated based on the obtained copper levels. The findings revealed that the mean levels and average daily intake in L. esculenta (0.3267 mg kg-1, 0.0279 mg kg-1 person-1) and C. lanatus (0.2523 mg kg-1, 0.0216 mg kg-1 person-1) did not differ considerably (p = 0.05) from each other while the two fruits had significantly higher values than C. sativus (0.1610 mg kg-1, 0.0137 mg kg-1 person-1). The copper levels and average daily intake values were below WHO/FAO and Tanzania Bureau of Standards per-missible limits. The human health index (HRI) was in the order: L. es-culenta > C. lanatus > C. sativus and all the values were less than unit, suggesting that there is no health risk from consuming the fruits. Con-cerning copper levels, the study concludes that the fruits are safe for human consumption.
Plants Used by Nyamwezi Traditional Health Practitioners To Remedy Sexually Transmitted Infections in Sikonge, Tanzania
(JEHS DUCE, 2021) Kacholi, David Sylvester; Amir, Halima Mvungi
This study aims to document medicinal plants used by Nyamwezi traditional health practitioners (NTHPs) in managing sexually transmitted infections (STIs) in Sikonge District. The data on medicinal plants were collected using a semi-structured questionnaire. A total of 23 NTHPs were interviewed. The findings revealed that 28 medicinal plants, belonging to 16 families and 25 genera, are used for the management of STIs in Sikonge. Most species belonged to family Fabaceae (17.9%), Apocynaceae, Combretaceae and Euphorbiaceae (10.7% each), and Olacaceae and Rutaceae (7.1% each). Out of the recorded plants, 45.7% are used to manage gonorrhoea, 25.7% syphilis, 17.1% vaginal candidiasis, 8.6% HIV/AIDS related infections and 2.9% chlamydia. Cassia abbreviata (47.8%), Ximenia caffra (39.1%) and Abrus precatorius (34.8%) were plants with high citation index. Tree (50.0%) and root (70.9%) were the most utilized growth form and plant part, respectively. 85.7% of the species were collected from the wild. Decoction (73.3%) and oral (86.2%) were the most used methods of preparation and administration of remedies, respectively. These study findings can serve as resource for the probe of bioactive components, which can lead to the discovery of contemporary drugs. Thus, the study recommends for pharmacological investigations of the reported plants, provision of awareness to NTHPs on sustainable harvest and conservation of the plants, and mentorship to the younger generation in an effort to preserve the indigenous knowledge.
Ethnobotanical survey of medicinal plants used by traditional healers in managing Gonorrhoea and Syphilis in Urambo District, Tabora Region, Tanzania
(Taylor and Francis, 2022-02-18) Kacholi, David Kacholi; Amir, Halima Mvungi
Medicinal plants used by traditional healers (THs) in managing gonorrhea and syphilis in Urambo District, Tabora Region, Tanzania, were documented. A semi-structured questionnaire was used to gather information on the use of medicinal plants. The findings revealed that 33 medicinal plants belonging to 18 families were used by the THs to manage gonorrhea and/or syphilis in Urambo District. Among the listed plants, Ximenia caffra, Friesodielsia obovata and Clerodendrum myricoides were frequently used by THs to manage gonorrhea while Ozoroa reticulata, Catunaregam spinosa, Annona senegalensis and Aloe vera were used to manage syphilis. Cassia abreviata, Strychnos spinosa, Strychnos potatorum and Entanda abyssinica were frequently used for the management of both ailments. Five species namely Oldfieldia dactylophylla, Flaucortia indica, Strophanthus eminii, Musa sapeintum and Phyllanthus engleri were recorded for the first time in the country’s ethnobotanical literature as a treatment of STIs. Many of the recorded plants also possessed antimicrobial properties.
Density and Aboriginal Uses of Wild Tree Species in Milawilila Forest Reserve in Morogoro Region, Tanzania
(College of Natural and Applied sciences, University Of Dar es Salaam, 2020-03) Kacholi, David Sylvester
This study assessed density and local uses of wild tree species in Milawilila forest reserve, Morogoro rural district. A total of six transects were set in the forest for assessing density and diversity of trees. In each transect, three plots of 20 m x 20 m were established and all trees with Diameter at Breast Height (DBH) ≥ 10 cm were identified, counted and DBH recorded in each plot. A semi structured questionnaire was used to obtain data on the use of tree species by the locals. Data were analyzed using Microsoft Excel and Statistical Package for Social Science software. A total of 172 trees/ha belonging to 20 species and 15 families were recorded in the forest. Among the families, Fabaceae was the richest family with 3 species, followed by Annonaceae and Cluciaceae with 2 species each. The most abundant species were Xylopia parviflora, Ehretia amoena and Diospyros squarrosa, which contributed 46% of the total tree density in the forest while the remaining 17 species contributed 54%. The Shannon-Wiener diversity index and basal area of the forest was 2.62 and 13.0 m2/ha, respectively. The forest exhibited good regeneration pattern. The proportion of tree species used for medicines was 76%, constructions 60%, fuelwood 56%, crafts 52%, and food/fodder 28%. The three species with high citation index were Albizia glaberrima (3.58), Annona senegalensis (3.38) and Scorodophleous fischeri (3.16). Since, majority of the observed species were less dense, the study suggests planting of the wild tree species should be prioritized to guarantee sustainability of the forest reserve and viable supply of forest products and services to the community.
Population structure, harvesting rate and regeneration status of four woody species in Kimboza forest reserve, Morogoro region - Tanzania
(Plants and Environment Research Institute, India, 2020-09-30) Kacholi, David Sylvester
Kimboza forest reserve is recognized as an IUCN category IV-habitat and species management area, but the information on population structure, harvesting rate and regeneration status of four commercial woody species, namely; Khaya anthotheca, Milicia excelsa, Pterocarpus angolensis and Dalbergia melanoxylon in the forest are lacking. This study, therefore, aims to fill this gap. A total of five transects were established in the forest whereby within each transect, five nested quadrats of 20 m × 20 m were placed at 200 m distance for sampling stems with diameter at breast height (DBH) ≥ 10 cm and stumps of the target species. Stems with DBH <10 cm were counted in a quadrat of 5 m × 5 m placed within the big quadrat. The findings show that density of stems & harvesting rate for Khaya anthotheca, Milicia excelsa, Pterocarpus angolensis and Dalbergia melanoxylon were 4.8 stems/ha & 6.6 stumps/ha, 12.6 stems/ha & 3.4 stumps/ha, 16.0 stems/ha & 2.8 stumps/ha, and 5.6 stems/ha & 1.2 stumps/ha, respectively. The DBH class distribution for Khaya anthotheca, Milicia excelsa and Pterocarpus angolensis displayed a good regeneration pattern, however, the last two were interrupted in high size classes. The Dalbergia melanoxylon revealed a poor regeneration pattern. The study recommends that illegal harvest of the species should be controlled, environmental education be provided to locals, and stringent measures be institutionalized against illegal loggers.
Ultra-Sensitive Detection of Plasmodium falciparum by Amplification of Multi-Copy Subtelomeric Targets
(PLOS, 2015-03-03) Hofmann, Natalie; Mwingira, Felista; Shekalaghe, Seif; Robison, Leanne; Muller, Ivo; Felger, Ingrid
Background Planning and evaluating malaria control strategies relies on accurate definition of parasite prevalence in the population. A large proportion of asymptomatic parasite infections can only be identified by surveillance with molecular methods, yet these infections also contribute to onward transmission to mosquitoes. The sensitivity of molecular detection by PCR is limited by the abundance of the target sequence in a DNA sample; thus, detection becomes imperfect at low densities. We aimed to increase PCR diagnostic sensitivity by targeting multi-copy genomic sequences for reliable detection of low-density infections, and investigated the impact of these PCR assays on community prevalence data. Methods and Findings Two quantitative PCR (qPCR) assays were developed for ultra-sensitive detection of Plasmodium falciparum, targeting the high-copy telomere-associated repetitive element 2 (TARE-2, *250 copies/genome) and the var gene acidic terminal sequence (varATS, 59 copies/genome). Our assays reached a limit of detection of 0.03 to 0.15 parasites/μl blood and were 10× more sensitive than standard 18S rRNA qPCR. In a population cross-sectional study in Tanzania, 295/498 samples tested positive using ultra-sensitive assays. Light microscopy missed 169 infections (57%). 18S rRNA qPCR failed to identify 48 infections (16%), of which 40% carried gametocytes detected by pfs25 quantitative reverse-transcription PCR. To judge the suitability of the TARE-2 and varATS assays for high-throughput screens, their performance was tested on sample pools. Both ultra-sensitive assays correctly detected all pools containing one low-density P. falciparum–positive sample, which went undetected by 18S rRNA qPCR, among nine negatives. TARE-2 and varATS qPCRs improve estimates of prevalence rates, yet other infections might still remain undetected when absent in the limited blood volume sampled. Conclusions Measured malaria prevalence in communities is largely determined by the sensitivity of the diagnostic tool used. Even when applying standard molecular diagnostics, prevalence in our study population was underestimated by 8% compared to the new assays. Our findings highlight the need for highly sensitive tools such as TARE-2 and varATS qPCR in community surveillance and for monitoring interventions to better describe malaria epidemiology and inform malaria elimination efforts.
Comparison of detection methods to estimate asexual Plasmodium falciparum parasite prevalence and gametocyte carriage in a community survey in Tanzania
(Springer Nature, 2014-11-18) Mwingira, Felista; Genton, Blaise; Kabanywanyi, Abdu-Noor M; Felger, Ingrid
Background The use of molecular techniques to detect malaria parasites has been advocated to improve the accuracy of parasite prevalence estimates, especially in moderate to low endemic settings. Molecular work is time-consuming and costly, thus the effective gains of this technique need to be carefully evaluated. Light microscopy (LM) and rapid diagnostic tests (RDT) are commonly used to detect malaria infection in resource constrained areas, but their limited sensitivity results in underestimation of the proportion of people infected with Plasmodium falciparum. This study aimed to evaluate the extent of missed infections via a community survey in Tanzania, using polymerase chain reaction (PCR) to detect P. falciparum parasites and gametocytes. Methods Three hundred and thirty individuals of all ages from the Kilombero and Ulanga districts (Tanzania) were enrolled in a cross-sectional survey. Finger prick blood samples were collected for parasite detection by RDT, LM and molecular diagnosis using quantitative 18S rRNA PCR and msp2 nPCR. Gametocytes were detected by LM and by amplifying transcripts of the gametocyte-specific marker pfs25. Results Results from all three diagnostic methods were available for a subset of 226 individuals. Prevalence of P. falciparum was 38% (86/226; 95% CI 31.9–44.4%) by qPCR, 15.9% (36/226; 95% CI 11.1–20.7%) by RDT and 5.8% (13/226; 95% CI 2.69- 8.81%) by LM. qPCR was positive for 72% (26/36) of the RDT-positive samples. Gametocyte prevalence was 10.6% (24/226) by pfs25-qRT-PCR and 1.2% by LM.
Population Pharmacokinetics and Clinical Response for Artemether-Lumefantrine in Pregnant and Nonpregnant Women with Uncomplicated Plasmodium falciparum Malaria in Tanzania
(American Society for Microbiology, 2014-07) Mosha, Dominic; Guidi, Monia; Mwingira, Felista; Abdulla, Salim; Mercier, Thomas; Decosterd, Laurent Arthur; Csajka, Chantal; Genton, Blaise
ABSTRACT Artemether-lumefantrine (AL) is the first-line treatment for uncomplicated malaria in the second and third trimesters of pregnancy. Its efficacy during pregnancy has recently been challenged due to altered pharmacokinetic (PK) properties in this vulnerable group. The aim of this study was to determine the PK profile of AL in pregnant and nonpregnant women and assess their therapeutic outcome. Thirty-three pregnant women and 22 nonpregnant women with malaria were treated with AL (80/480 mg) twice daily for 3 days. All patients provided five venous plasma samples for drug quantification at random times over 7 days. Inter- and intraindividual variability was assessed, and the effects of covariates were quantified using a nonlinear mixed-effects modeling approach (NONMEM). A one-compartment model with first-order absorption and elimination with linear metabolism from drug to metabolite fitted the data best for both arthemether (AM) and lumefantrine (LF) and their metabolites. Pregnancy status and diarrhea showed a significant influence on LF PK. The relative bioavailability of lumefantrine and its metabolism rate into desmethyl-lumefantrine were, respectively, 34% lower and 78% higher in pregnant women than in nonpregnant patients. The overall PCR-uncorrected treatment failure rates were 18% in pregnant women and 5% in nonpregnant women (odds ratio [OR] = 4.04; P value of 0.22). A high median day 7 lumefantrine concentration was significantly associated with adequate clinical and parasitological response (P = 0.03). The observed reduction in the relative bioavailability of lumefantrine in pregnant women may explain the higher treatment failure in this group, mostly due to lower posttreatment prophylaxis. Hence, a modified treatment regimen of malaria in pregnancy should be considered.
Effectiveness of intermittent preventive treatment with sulfadoxine–pyrimethamine during pregnancy on placentalmalaria, maternal anaemia and birthweight in areas with highand low malaria transmission intensity in Tanzania
(2014 John Wiley & Sons Ltd, 2014-09) Mosha, Dominic; Chilongola, Jaffu; Ndeserua, Rabi; Mwingira, Felista; Genton, Blaise
objective To assess the effectiveness of IPTp in two areas with different malaria transmission intensities. methods Prospective observational study recruiting pregnant women in two health facilities in areas with high and low malaria transmission intensities. A structured questionnaire was used for interview. Maternal clinic cards and medical logs were assessed to determine drug intake. Placental parasitaemia was screened using both light microscopy and real-time quantitative PCR. results Of 350 pregnant women were recruited and screened for placental parasitaemia, 175 from each area. Prevalence of placental parasitaemia was 16.6% (CI 11.4–22.9) in the high transmission area and 2.3% (CI 0.6–5.7) in the low transmission area. Being primigravida and residing in a high transmission area were significant risk factors for placental malaria (OR 2.4; CI 1.1–5.0; P = 0.025) and (OR 9.4; CI 3.2–27.7; P < 0.001), respectively. IPTp was associated with a lower risk of placental malaria (OR 0.3; CI 0.1–1.0; P = 0.044); the effect was more pronounced in the high transmission area (OR 0.2; CI 0.06–0.7; P = 0.015) than in the low transmission area (OR 0.4; CI 0.04–4.5; P = 0.478). IPTp use was not associated with reduced risk of maternal anaemia or low birthweight, regardless of transmission intensity. The number needed to treat (NNT) was four (CI 2–6) women in the high transmission area and 33 (20–50) in the low transmission area to prevent one case of placental malaria. conclusion IPTp may have an effect on lowering the risk of placental malaria in areas of high transmission, but this effect did not translate into a benefit on risks of maternal anaemia or low birthweight. The NNT needs to be considered, and weighted against that of other protective measures, eventually targeting areas which are above a certain threshold of malaria transmission to maximise the benefit.
Malaria prevalence in asymptomatic and symptomatic children in Kiwangwa, Bagamoyo district, Tanzania
(Springer Nature, 2017-05-25) Sumari, Deborah; Mwingira, Felista; Majige, Selemani; Mugittu, Kefas; Mugasa, Joseph; Gwakisa, Paul
Background Malaria prevalence continues to decline across sub-Saharan Africa as a result of various intervention strategies. However, the diseases still poses a public health concern in the region. While symptomatic malaria is recognized and treated, asymptomatic infections become increasingly important for interrupting transmission. A cross-sectional survey was conducted to assess malaria prevalence in symptomatic and asymptomatic children in Kiwangwa ward in Bagamoyo District in Tanzania. Methods Four hundred school-aged children in Kiwanga ward were recruited in the study; 200 from Kiwangwa dispensary and 200 from nearby schools. Primary health parameters were examined and blood samples collected and examined for Plasmodium falciparum prevalence using rapid diagnostic test (RDT), light microscopy (LM) and reverse transcription quantitative PCR (RT-qPCR) targeting transcripts of A-type 18s rRNA of P. falciparum. Gametocytes were detected by LM and RT-qPCR targeting transcripts of gametocyte specific marker, Pfs25. Results Overall P. falciparum prevalence was 73.3, 40.8 and 36.3% by RT-qPCR, RDT and LM in the study area, respectively (P < 0.001). As expected symptomatic children had a significantly higher prevalence of 89, 67.5 and 64.5% by qPCR, RDT and LM, compared to 57.5, 14 and 8% in the asymptomatic group, respectively. However, gametocyte prevalence in asymptomatic individuals was higher by both LM (2%) and qPCR (14%) than in symptomatic individuals LM (0.5%) and qPCR (3%). Conclusions A substantial difference in prevalence of symptomatic and asymptomatic infections observed in Kiwangwa ward underpins the use of molecular tools in malaria surveillance aiming at estimating prevalence and transmission. Notably, the higher gametocytaemia observed in asymptomatic children indicates the reservoir infections and points to the need for detection and treatment of both asymptomatic and symptomatic malaria.
The temporal dynamics and infectiousness of subpatent Plasmodium falciparum infections in relation to parasite density
(Nature Communications, 2019-03-29) Slater, Hannah; Ross, Amanda; Felger, Ingrid; Hofmann, Natalie; Robison, Leanne; cook, Jackie; Gonçalves, Bronner; Bjòrkman, Andes; Ouedraogo, Andre; Morris, Ulrika; Msellem, Mwinyi; Koepfli, Christian; Muller, Ivo; Tadesse, Fitsum; Gadisa, Endalamaw; Das, Simita; Domingo, Gonzalo; Kapulu, Melissa; Midega, Janet; Owusu-Agyei, Seth; Nabet, Cecile; Piarroux, Renaud; Duombo, Ogobara; Niare, Safiatou; koram, Kwadwo; Lucci, Nami; Udhayakumar, Venkatachalam; Mosha, Jackline; Tiono, Alfred; Chandramohan, Daniel; Gosling, Roly; Mwingira, Felista; Sauerwein, Robert; Paul, Richard; Riley, Eleanor; White, Nicholas; Nosten, Francois; Imwong, Mallika; Bousema, Teun; Drakeley, Chris; Okell, Lucy
Malaria infections occurring below the limit of detection of standard diagnostics are common in all endemic settings. However, key questions remain surrounding their contribution to sustaining transmission and whether they need to be detected and targeted to achieve malaria elimination. In this study we analyse a range of malaria datasets to quantify the density, detectability, course of infection and infectiousness of subpatent infections. Asymptomatically infected individuals have lower parasite densities on average in low transmission settings compared to individuals in higher transmission settings. In cohort studies, subpatent infections are found to be predictive of future periods of patent infection and in membrane feeding studies, individuals infected with subpatent asexual parasite densities are found to be approximately a third as infectious to mosquitoes as individuals with patent (asexual parasite) infection. These results indicate that subpatent infections contribute to the infectious reservoir, may be long lasting, and require more sensitive diagnostics to detect them in lower transmission settings.
Assessment of Tree Species Richness, Diversity, Population Structure and Natural Regeneration in Nongeni Forest Reserve in Morogoro Region, Tanzania
(Tanzania Journal of Science, 2019) Kacholi, David Sylvester
This study examined tree species richness, diversity, population structure and regeneration in Nongeni forest reserve, Morogoro, Tanzania. The study deployed plot sampling technique whereby a total of 20 plots of 0.05 ha each were randomly established in the forest. All species and individuals encountered in each plot were counted, identified and DBH measured. A total of 751 individuals/ha representing 24 species belonging to 11 families were recorded. Family Fabaceae was dominant with 9 species. The Shannon-Wiener, Margalef, Simpson‟s and Pielou J index were calculated as 2.667, 3.474, 10.58 and 0.839, respectively. The Diplorhynchus condylocarpon (52.18) was the dominant species in terms of species importance value index (IVI) followed by Antidesma venosum (27.40) and Stereospermum kunthianum (21.16). The forest mean basal area was 10.80 m2/ha whereby D. condylocarpon (2.26 m2/ha) had highest value followed by Julbernardia globiflora (1.36 m2/ha). Of the observed species, 12.5% exhibited good regeneration, 45.8% poor regeneration, 29.2% new regeneration and 12.5% displayed fair/hampered regeneration pattern. Also, 29.1% of the species displayed both poor regeneration pattern and low IVI. The study concludes that the forest was rich in tree species and had good regeneration. However, conservation attention and proper management strategies for the species that exhibited poor regeneration and low IVI is imperative.
Floristic Similarity and Diversity Gradients in the Eastern Arc and Coastal Forests of Tanzania
(Dar es Salaam University College of Education (DUCE), 2018-12-19) Kacholi, David Sylvester
The Eastern Arc and Coastal forests of Tanzania are biodiversity hotspots, centres of endemism, and highest priority ecosystems for biodiversity conservation worldwide. But, their floristic similarity and species diversity gradients over geographical distances and longitudinal locations, respectively, are poorly understood. Thus, this study investigates the relationship between floristic similarity and geographical distances, as well as species diversity and longitudinal locations among the forests. A total of 37 inventories from the Eastern Arc and Coastal forests of Tanzania were selected based on inventories with minimum diameter at breast height (DBH) ≥ 10cm), and identification of trees done at species level. The floristic similarity was determined using the Sørensen’s similarity coefficient. The Pearson correlation test was used to study differences between floristic similarities and geographical distances, as well as species diversity and longitudinal location. The findings revealed three clusters of forests assembled due to their geographical proximity. The correlation between geographical distances and floristic similarities revealed a significant negative association (n = 528, R2 = 0.1821, p < 0.001), while species diversity and longitudinal location of forests had a significant positive correlation (n = 37, R2 = 0.5401, P < 0.05). The results suggest that high environmental heterogeneity across the forests should be well thought-out in their management plans to uphold their values
Distribution Patterns of Gastrointestinal Parasites in Vervet Monkeys (Chlorocebus pygerythrus) at Gombe National Park, Tanzania
(Tanzania Journal of Science, 2018) Bakuza, Jared S.
Vervet monkeys at Gombe National Park in western Tanzania constitute a key component of the park’s ecosystem through interactions with other animals and people in the area. However, the parasite fauna of these animals has not been investigated. Thus, 21 faecal samples obtained from the animals in September 2010 were examined for parasites using formol-ethyl technique. The parasites observed included Trichuris spp., Physaloptera spp., hookworms and unidentified nematodes. While egg counts for unidentified nematodes did not vary with vervet monkey communities (z = 0.759, p = 0.448), other parasites were significantly higher among vervets at north of the park near Mwamgongo village compared to those at southern park border close to Mtanga village (Trichuris spp.: z = 2.443, p = 0.0146; Hookworms: z = 2.084, p = 0.0371). This is the first baseline study on vervet monkey parasites at Gombe and it broadens our understanding of the animals’ ecology and health. The observed parasites namely Trichuris and hookworms are also common in human populations in the area, and this suggests a potential health risk given the existing animal-human interactions. This stresses the need to better understand how these findings
Trematodes of Primates. The International Encyclopedia of Primatology
(JohnWiley & Sons, Inc, 2017) Gilespie, Thomas R.; Bakuza, Jared S.
Variation over Time in Parasite Prevalence Among Free-ranging Chimpanzees at Gombe National Park, Tanzania
(International Journal of Primatology, 2009) Bakuza, Jared S.; Nkwengulila, Gamba
From January to September, 2005, we collected fecal samples from 60 chimpanzees at Gombe National Park, Tanzania and examined them for parasites. We compared current parasite prevalence data with previous studies to obtain a pattern of parasitism over time. There were considerable similarities in the parasite species composition and prevalence, although we noted some variations. Generally, parasite prevalence decreased over time, with the present prevalence being lower than in previous surveys. We identified 8 types of parasites, all of which had previously been documented in the chimpanzees of Gombe. Three nematodes — Oesophagostomum sp., Strongyloides fulleborni, and Abbreviata caucassica— occurred at higher prevalence (41.2–45.5%) but relatively lower than previous findings of 50–91%. We also diagnosed unidentified strongyles at a moderate prevalence (33%), lower than a previous record of 41%. Probstmayria gombensis occurred at relatively low prevalence (16.4%) vs. past observations (23–59%), while the prevalence of Trichuris sp. (7.3%) was closely similar to previous records of 5– 9%. We also observed unidentified ciliate at 9% within the same range as in previous studies (5–28%). The prevalence of Troglodytella abrassarti was 78%, closely similar to previous findings of 75%. There was no significant variation in parasite prevalence between chimpanzees of the Kasekela community and those of the Mitumba community, although the former tended to have higher prevalence of helminths than the latter. The causes of the similarities and variations in parasite prevalence over time are discussed. The study provides baseline data for monitoring of chimpanzee health at Gombe.
Prevalence and Intensity of Schistosomiasis in Communities around Water Reservoirs in Malawi
(Journal of Tropical Diseases, 2015) Mtethiwa, Austin; Nkwengulila, Gamba; Bakuza, Jared S.
Although schistosomiasis is endemic in Malawi, its epidemiology at water reservoir communities is not known. However, there are more than 750 water reservoirs spread throughout the country, providing water for various activities. The present study was conducted to determine schistosomiasis infection at reservoir communities in Malawi. Methods: This was across sectional study conducted during the rainy and dry seasons at three water reservoir communities. A total of 1594 individuals aged from 1 to 78 years from 1-2km, >2-5km and 5km away from the reservoir were randomly selected and enrolled into the study. They provided stool and urine samples which were examined for Schistosoma eggs using Kato-Katz and sedimentation methods, respectively. Results: An overall prevalence of 47.4% was found with 51.2% for S. haematobium and 9.5% for S. mansoni. Prevalence was significantly higher during the dry season (58.5%) than the rainy season (36.6%) (P=0.01). Prevalence was significantly higher in communities living 0-2km away from the reservoir than in those living > 5km away (P=0.00). Prevalence of S. haematobium was significantly different higher at Mlala reservoir than at Ukonde and Njala reservoirs (P=0.043). Prevalence of S. Mansoni was significantly higher at Ukonde reservoir than at Mlala and Njala reservoirs (P=0.037). Prevalence among different age groups was not significantly different (P=0.29). Age group of 6-15 years had significantly higher infection intensity, in both S. mansoni (129±3.6 epg) and S. haematobium (63.3±2.3 eggs/10ml of urine), than the other age groups. Conclusion: Water reservoirs are infested with Schistosoma cercariae and the communities are at risk. The closer to the reservoir, the higher the chances of being infected. We recommend annual MDA, since the prevalence found is within the ≥50% WHO recommended threshold for MDA. We also recommend a health education to the communities on transmission and prevention of schistosomiasis.
Extent of morbidity associated with schistosomiasis infection in Malawi: a review paper.
(Infectious Diseases of Poverty, 2015-05) Mtethiwa, Austin; Nkwengulila, Gamba; Sikawa, D.; Kazembe, A.
Data on the extent of the burden due to schistosomiasis is sparse in most Sub-Saharan African countries. However, this data is crucial for triggering medical attention. A review of extent of morbidity and determinants associated with schistosomiasis in Malawi was therefore conducted to quantify the infection in order to concretise the need for medical intervention. A systematic and traditional search strategy was used to find literature for the review, whilst exclusion and inclusion criteria were used to identify appropriate articles. Logistic regression curves of epidemiological model Y = (a + bxc)/(1 + bxc) and the recommendation that schistosomiasis prevalence can be used to estimate morbidity were employed to quantify morbidity at various infection stages. Morbidity was quantified as a direct proportion of the population and the respective national schistosomiasis prevalence. Findings showed that both S. mansoni and S. haematobium are present in Malawi with the latter highly prevalent (50%). Furthermore, out of the estimated population of 16,829 million, approximately 8.4 million have schistosomiasis, with about 4.4 million of these aged 18 years and below. The most frequent manifestation is Katayama syndrome, while ascites is the lowest, impacting about 3.0 million and 960 individuals, respectively. Localised studies on association of schistosomiasis infection to risk factors such as occupation, age and gender found odds ratio (OR) ranging from 1.29 to 5.37. Morbidity due to schistosomiasis is high in Malawi. It is therefore recommended that a more detailed study on the determinants of high schistosomiasis and re-evaluation of the current control measures be conducted if the current morbidity statistics are to be remarkably reduced
Socioecological correlates of clinical signs in two communities of wild chimpanzees (Pan troglodytes) at Gombe National Park, Tanzania
(American Journal of Primatology, 2016) Lonsdorf, Elizabeth V.; Gilespie, Thomas R.; Wolf, Tiffany M; Lipende, Idd; Raphael, Jane; Bakuza, Jared S.; Murray, Carson; Wilson, Michael; Kamenya, Shadrack; Mjungu, Deus; Collins, D Anthony; Gilby, Ian; Stanton, Margaret; Terio, Karen; Barbian, Hannah; Li, Yingying; Krupnick, Alexander; Seidl, Emily; Goodall, Jane; Hahn, Beatrice; Pusey, Anne; Dominic, Travis
Disease and other health hazards pose serious threats to the persistence of wild ape populations. The total chimpanzee population at Gombe National Park, Tanzania, has declined from an estimated 120 to 150 individuals in the 1960's to around 100 individuals by the end of 2013, with death associated with observable signs of disease as the leading cause of mortality. In 2004, we began a non-invasive health-monitoring program in the two habituated communities in the park (Kasekela and Mitumba) with the aim of understanding the prevalence of health issues in the population, and identifying the presence and impacts of various pathogens. Here we present prospectively collected data on clinical signs (observable changes in health) in the chimpanzees of the Kasekela (n=81) and Mitumba (n=32) communities over an 8-year period (2005–2012). First, we take a population approach and analyze prevalence of clinical signs in five different categories: gastrointestinal system (diarrhea), body condition (estimated weight loss), respiratory system (coughing, sneezing etc.), wounds/lameness, and dermatologic issues by year, month, and community membership. Mean monthly prevalence of each clinical sign per community varied, but typically affected <10% of observed individuals. Secondly, we analyze the presence of clinical signs in these categories as they relate to individual demographic and social factors (age, sex, and dominance rank) and simian immunodeficiency virus (SIVcpz) infection status. Adults have higher odds of being observed with diarrhea, loss of body condition, and wounds or lameness when compared to immatures, while males have a higher probability of being observed with wounds or lameness than females. In contrast, signs of respiratory illness appear not to be related to chimpanzee-specific factors and skin abnormalities are very rare. For a subset of known-rank individuals, dominance rank predicts the probability of wounding/lameness in adult males, but does not predict any adverse clinical signs in adult females. Instead, adult females with SIVcpz infection are more likely to be observed with diarrhea, a finding that warrants further investigation. Comparable data are needed from other sites to determine whether the prevalence of clinical signs we observe are relatively high or low, as well as to more fully understand the factors influencing health of wild apes at both the population and individual level.
Are small-scale coffee farmers in Tanzania safe from potential agrochemical health hazards? Week in Review, Biosciences for Farming in Africa (B4FA).
(Biosciences for Farming in Africa, 2016-01-15) Bakuza, Jared S.
http://b4fa.org/are-small-scale-coffee-farmers-in-tanzania-safe-from-potential-agrochemical-health-hazards/

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