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Synthetic gut microbiome: Advances and challenges
(Elsevier, 2020) Mabwi, Humphrey A.; Kim, Eunjung; Song, Dae-Geun; Yoon, Hyo Shin; Pan, Cheol-Ho; Komba, Erick V.G.; Ko, GwangPyo; Hyun Cha, Kwang
An exponential rise in studies regarding the association among human gut microbial communities, human health, and diseases is currently attracting the attention of researchers to focus on human gut microbiome research. However, even with the ever-growing number of studies on the human gut micro- biome, translation into improved health is progressing slowly. This hampering is due to the complexities of the human gut microbiome, which is composed of >1,000 species of microorganisms, such as bacteria, archaea, viruses, and fungi. To overcome this complexity, it is necessary to reduce the gut microbiome, which can help simplify experimental variables to an extent, such that they can be deliberately manip- ulated and controlled. Reconstruction of synthetic or established gut microbial communities would make it easier to understand the structure, stability, and functional activities of the complex microbial commu- nity of the human gut. Here, we provide an overview of the developments and challenges of the synthetic human gut microbiome, and propose the incorporation of multi-omics and mathematical methods in a better synthetic gut ecosystem design, for easy translation of microbiome information to therapies.
Sanitary practices and occurrence of zoonotic conditions in cattle at slaughter in Morogoro Municipality, Tanzania: implications for public health
(Tanzania Journal of Health Research, 2012) Komba, Erick V.G.; Komba, Ewaldo V; Mkupasi, Ernatus M.; Mbyuzi, Albano O.; Mshamu, Shaabani; Luwumba, Denice; Busagwe, Zablon; Mzula, Alexanda
As meat consumption is increasing worldwide to cover for protein demands, also raise concerns and challenges regarding meat hygiene and safety. The current one year follow up study aimed at investigating on sanitary practices and occurrence of zoonotic conditions, during post- mortem examination, in cattle at slaughter in Morogoro Municipality abattoir. Sanitary practices were assessed through direct observation where as routine post-mortem inspection procedures were employed to detect zoonotic conditions in cattle at slaughter. During the study period a total of 30,713 cattle were slaughtered and inspected at the abattoir. Results revealed poor hygienic practices at the level of abattoir surrounding, the slaughter operation area, personnel as well as meat vans. Whole carcasses, lungs, livers, hearts and heads were condemned due to zoonotic conditions at rates of 0.026%, 1.96%, 1.61%, 0.02% and 0.21% respectively. Bovine tuberculosis, Cysticercus bovis cysts, fasciolosis and hydatidosis were the responsible zoonotic conditions for the condemnations. Bovine tuberculosis was a leading zoonotic cause of condemnations accounting for 95.7% of lungs and 100% of all head and carcass condemnations. Cysticercus bovis cysts were ranking the second in serving as causes of condemnations closely followed by fasciolosis and lastly hydatidosis. Occurrence of disease conditions with zoonotic implication in cattle at slaughter, meant for human consumption, may pose significant economic and public health risks to especially disaster-prone marginalized communities. Thus, there is a need to introduce appropriate control measures of livestock diseases to minimize the rate of infection; and eventually reduce economic losses and safeguard public health.
Prevalence, risk factors, and antimicrobial resistance profiles of thermophilic campylobacter species in humans and animals in Sub-Saharan Africa: a systematic review
(International Journal of Microbiology, 2020) Gahamanyi, Noel; Mboera, Leonard E. G.; Matee, Mecky I.; Mutangana, Dieudonn´e; Komba, Erick V. G.
Termophilic Campylobacter species are clinically important aetiologies of gastroenteritis in humans throughout the world. -e colonization of different animal reservoirs by Campylobacter poses an important risk for humans through shedding of the pathogen in livestock waste and contamination of water sources, environment, and food. A review of published articles was conducted to obtain information on the prevalence and antimicrobial resistance (AMR) profiles of thermophilic Campylobacter species in humans and animals in sub-Saharan Africa (SSA). Electronic databases, namely, PubMed, Google Scholar, Resear- ch4life-HINARI Health, and Researchgate.net, were searched using the following search terms “thermophilic Campylobacter,” “Campylobacter jejuni,” “Campylobacter coli,” “diarrhea/diarrhoea,” “antimicrobial resistance,” “antibiotic resistance,” “humans,” “animals,” “Sub-Saharan Africa,” and “a specific country name.” Initially, a total of 614 articles were identified, and the lists of references were screened in which 22 more articles were identified. After screening, 33 articles on humans and 34 on animals and animal products were included in this review. In humans, Nigeria reported the highest prevalence (62.7%), followed by Malawi (21%) and South Africa (20.3%). For Campylobacter infections in under-five children, Kenya reported 16.4%, followed by Rwanda (15.5%) and Ethiopia (14.5%). -e country-level mean prevalence in all ages and under-five children was 18.6% and 9.4%, respectively. -e prevalence ranged from 1.7%–62.7% in humans and 1.2%–80% in animals. -e most reported species were C. jejuni and C. coli. -e AMR to commonly used antimicrobials ranged from 0–100% in both humans and animals. Poultry consumption and drinking surface water were the main risk factors for campylobacteriosis. -e present review provides evidence of thermophilic Campylobacter occurrence in humans and animals and high levels of AMR in SSA, emphasizing the need for strengthening both national and regional multisectoral antimicrobial resistance standard surveillance protocols to curb both the campylobacteriosis burden and increase of antimicrobial resistance in the region.
Ectoparasites and hemoparasites of the Emini Silvery Mole rats (Heliophobius Argentiocinereus Emini) in Morogoro region, Tanzania Essau Elly Mwalukasa
(Journal of Ideas in Health, 2025) Shija,Debora Elias; Ngalameno,Mungo Kisinza; Nzalawahe,Jahashi Said
Background: The silvery mole rat (Heliophobius Argentiocinereus Emini) is a subterranean rodent widely distributed across Sub-Saharan Africa and exploited as a protein source in some communities. Despite this, limited data exist on ectoparasite and hemoparasite infections in this species in Tanzania. This study aims to determine the prevalence of hemoparasites in silvery mole rats and to identify their potential arthropod vectors in the Morogoro region of Tanzania. Methods: A cross-sectional study was conducted in Mvomero and Morogoro districts, Tanzania, between March and June 2023. A total of 137 silvery mole rats were captured through manual excavation. Ectoparasites were collected from animal fur and identified morphologically using taxonomic keys. Blood samples were obtained directly from the heart, and smears were prepared, stained with Giemsa, and microscopically examined for hemoparasites. Statistical analysis was performed to assess associations between host factors, ectoparasite infestation, and hemoparasite infection. Results: Of the 137 captured mole rats, 65% (n=89) were females and 86.7% (n=120) were adults. The overall prevalence of ectoparasitism was 71.5% (98/137). A total of 1,503 ectoparasites were recovered, dominated by Androlaelaps spp. (93.15%, n=1400), followed by Echinolaelaps echidinus (6.19%, n=93), and Haemaphysalis spp. ticks (0.67%, n=10). Hemoparasites were detected in 29.2% (40/137) of hosts, including Anaplasma spp. (25.5%) and Babesia spp. (16.8%). Coinfections with both parasites occurred in 13.1% of individuals. Adult mole rats had significantly higher odds of hemoparasite infection (OR = 3.23, 95% CI: 1.15–9.11, p = 0.04). Tick infestation was strongly associated with Babesia spp. (χ² = 11.91, OR = 15.56, p < 0.001) and Anaplasma spp. (χ² = 5.82, OR = 8.3, p = 0.01). Conclusion: This study demonstrates a high prevalence of ectoparasites and hemoparasites among silvery mole rats in the Morogoro region. The dominance of mite infestations and significant associations between ticks and blood parasites highlight the potential role of mole rats as reservoirs of zoonotic pathogens. Further molecular studies are warranted to characterize these parasites and evaluate their public health implications.
Cestodes fauna of silvery mole rats (Heliophobius Argentiocinereus Emini) in Morogoro region, Tanzania
(Journal of Ideas in Health, 2024) Shija,Debora Elias; Nzalawahe,Jahashi Saidi; Ngalameno,Mungo Kisinza; Mafie,Eliakunda M
Background: Silvery mole rat (Heliophobius Argentiocinereus) is a subterranean rodent widely distributed throughout Sub-Saharan Africa. They have been reported to host several gastrointestinal parasites, however, the status of parasites from these rats in Tanzania has not been widely studied. This study aimed to investigate the prevalence of cestodes parasites in silvery mole rats from the Morogoro region. Methods: A cross-sectional study was conducted in the Mlali and Mji mkuu wards of the Mvomero and Morogoro urban districts in Tanzania, from March to June 2023. Silvery mole rats were collected through manual excavation of their burrows in agri-ecological areas. The captured rats were euthanized using Diethyl Ether and dissected to remove the gastrointestinal tract (GIT). GIT contents were gathered. Adult worms were collected and preserved in 70.0% ethanol. A flotation and aceto-carmine staining techniques were employed to process gastrointestinal contents and adult tapeworms respectively. Both cestode eggs and adult tapeworms were identified based on general morphological features using taxonomic keys. The prevalence of cestodes was computed, and a chi-square test was applied to assess association, a p-value≤ 0.05 was considered significant. Results: One hundred thirty-seven silvery mole rats were collected, adult females 65% (89/137) were dominant among collected rats. One species of gastrointestinal cestode was detected with an overall prevalence of 20.44% (28/137) and identified as Hymenolepis diminuta. A total of 392 adult worms and 1450 eggs per gram (EPG) for H. diminuta were collected from the gastrointestinal tract. A significant association was shown between cestodes infection with both host age and reproductive category (p< 0.05). Conclusion: This study has established that Hymenolepidae (H. diminuta) is prevalent in silvery mole rats of the Morogoro region, suggesting that this animal could be among the sources of hymenolepiasis disease in the community. Therefore, further studies are needed to investigate cestodes fauna in community members of the respective study area.
Prevalence of Gastrointestinal Nematodes in Silvery Mole-Rats in the Morogoro Region, Tanzania
(Journal of Applied Veterinary Science and Technology, 2025) Shija,Debora Elias; Nzalawahe,Jahashi S; Ngalameno,Mungo Kisinza; Mafie,Eliakunda M
Exploring the nematode diversity in silvery mole rats opens up a fascinating avenue for understanding the intricate relationships between underground-dwelling mammals and their parasites. It is intriguing to consider the potential transmission of parasitic zoonotic between humans, livestock, and silvery mole rats due to the notable interactions of these animals. This study aims to acquire crucial information about the nematode fauna in silvery mole rats in the Morogoro region, Tanzania. A survey of nematode parasites in silvery mole rats was conducted in the Morogoro region, from March to June 2023. Collected rats were euthanized using Diethyl Ether, and dissected to remove the gastrointestinal tract (GIT). Adult worms were collected and preserved in 70% ethanol. A flotation method and lactophenol mounting techniques were employed to process gastrointestinal contents and adult roundworms. The prevalence of nematodes was computed, and a chi-square test was applied to assess the relationship, a p-value< 0.05 was considered significant. The examination of the gastrointestinal tract contents revealed two nematode taxa; Physaloptera spp. and Strongyloides spp. The overall prevalence of nematode infection was 38.69% (53/137), with Physaloptera species being the most prevalent (37.22%). Adult rats had a lower infection risk than sub-adult rats. Female silvery mole rats were at higher risk of being infected compared to males. The study established two nematodes in silvery mole rats of Morogoro region, Tanzania, which are Physaloptera spp. and Strongyloides spp.
The efficacy of crude extract of aloe secundiflora on candida albicans
(Msoffe and Mbilu Afr. J. Trad. CAM, 2009) Peter L. M; Mbilu, Z. M
In- vitro studies on the efficacy of crude extracts of Aloe secundiflora on Candida albicans was conducted. Five mature leaves of Aloe secundiflora were collected and the crude extract was prepared, then autoclaved. The extract was then tested on Candida albicans grown on solid media. The results from these studies revealed complete inhibition of Candida albicans growth caused by Aloe secundiflora crude extract on solid media. The findings from this study suggest that the crude extract of Aloe secundiflora can inhibit the growth of Candida albicans. Further studies are required to establish the in-vivo activity of the crude extract, the active ingredient, dosage and safety of Aloe secundiflora, before recommending for clinical use.
Virulence pattern of circulating aeromonads isolated from farmed nile tilapia in Tanzania and novel antibiotic free attenuation of aeromonas hydrophila strain tzr7-2018
(Aquaculture Reports, 2020) Mzula, Alexanda; Wambura, Philemon N; Mdegela, Robinson H; Shirima, Gabriel M
Aeromonads are gram-negative, rod-shaped, facultative anaerobes bacteria known to cause motile aeromonads septicemia diseases (MAS) in warm freshwater farmed fish. Outbreaks are associated with pathogenicity of aeromonads in fish which is partly contributed by virulence characteristics of the etiological agent. The objective of this study was to assess the virulence characteristics of the previously isolated and identified aeromonads, and attenuate potential Aeromonas hydrophila strain TZR7-2018 to serve as local vaccine candidate. Six virulence genes and other virulence characteristics were molecularly and phenotypically assessed both using in-vitro and in-vivo approaches. Attenuation of A. hydrophila parent strain TZR7-2018 + was performed by passaging through thermal continuous sub-culturing 40 times in Tryptic soy agar (TSA). Bacterin was prepared by formalin in- activation from the same parent strain. Humoral responses were assayed using quantitative serological agglu- tination test (qSAT) while protective efficacy was measured through relative percent survival (RPS). A total 240 Nile tilapia fingerlings with an average weight of 8.1 ± 0.4 g were used in all in-vivo studies. The presence of aerolysin (aer), cytotoxic enterotoxin (act), elastase (ahy), haemolysin (hly), serine (ser) and polar flagella (fla) genes were determined using PCR. Out of 201 isolates, 75.1 % (151/201) of the aeromonads possessed virulence genes (120=A. hydrophila and 31=Aeromonas veronii). The virulence gene pattern of aer/hly/fla was the most prominent with the prevalence of 12.6 %. The attenuated strain TZR7-2018 − showed reduced: colon size, multiplication rate, cell size and loss in; haemolysis, motility and capsule. Humoral responses increased gra- dually and reached maximum at day 28 in both attenuated and bacterin formulation given through in- traperitoneal (IP) injection and immersion (IM). A RPS of 82.3 %, 71.4 % and 85.1 %, were recorded to the attenuated vaccine given through IP and IM and bacterin provided through IP respectively. Therefore the attenuated strain TZR7-2018 − obtained through thermal continuous subculture technique and the bacterin proved to be efficacious and can serve as vaccine candidate.
Current state of modern biotechnological-based aeromonas hydrophila Vaccines for aquaculture: a systematic review
(Hindawi BioMed Research International, 2019-07-29) Mzula, Alexanda; Wambura, Philemon N; Mdegela, Robinson H; Shirima, Gabriel M
This systematic review describes what “the cutting edge vaccines for Aeromonas hydrophila are”. The focus is on types of high tech biotechnological based vaccines, target gene or antigen in developing these vaccines, and challenge model fish species used in vaccines efficacy testing. Vaccines delivery methods, immune response, and their efficacy, adjuvant or carrier systems used, and the overall experimental setup or design of the vaccines under investigation are also described. The search for the original papers published between 2009 and 2018 was conducted in June of 2018, using the PubMed and Google scholar electronic database. Twenty- three (23/4386) studies were included in the final assembly using PRISMA guidelines (Protocol not registered). Recombinant protein vaccines were the highly experimented type of the modern biotechnological based vaccines identified in the selected studies (16/23; 70%). Outer membrane proteins (OMPs) of different β-barrels were shown to be a potential antigenic entity for A. hydrophila vaccines (57%). Intraperitoneal route with conventional carries or adjuvants was the highly applied delivery system while very few studies used herbal based vaccine adjuvants and nanomaterial as a vaccine carrier. Variation was observed in terms of protection levels in the selected studies. The experimental designs partly contributed to the observed variation. Therefore, recombinant vaccines that use new carrier system technologies and delivered through oral route in feeds would have been of great value for use in the prevention and control of A. hydrophila infections in fish. Despite the usefulness as academic tools to identify what is important in pathogenicity of the etiological agent to the host fish, these vaccines are only economically viable in very high-value animals. Therefore, if vaccination is a good option for A. hydrophila group, then simple autogenous vaccines based on accurate typing and evidence-based definition of the epidemiological unit for their use would be the most viable approach in terms of both efficacy and economic feasibility especially in low and middle-income countries (LMIC).
Antibiotic-resistant microbial populations in urban receiving waters and wastewaters from Tanzania
(Environmental Chemistry and Ecotoxicology, 2023) Ripanda, Asha Shabani; Rwiza, Mwemezi J; Nyanza, Elias Charles; Miraji, Hossein; Bih, Numfor Linda; Mzula, Alexanda; Mwega, Elisa; Njau, Karoli N; Vuai, Said Ali Hamad; Machunda, Revocatus L
Antimicrobial resistance against certain medications in the pathogenic microbial community is globally increasing due to the continual discharge and disposal of pharmaceuticals in the environment. The phenomenon resulted in significant antibiotic resistance among several exposed Enterobacteriaceae species, with wastewater treatment plants (WWTPs) and rivers serving as significant reservoirs. Despite antibiotic resistance being a tragedy, particularly in treating diseases by using antibiotics, local and regional studies indicating the severity, resistant species and the molecular level insight into these pathogens are scarce, thus requiring immediate intervention. This study, therefore, investigated wastewater from wastewater treatment ponds and receiving waters for the presence of resistant patho- gens through phenotypical and molecular approach screening of their genes. Among the 57 analyzed samples, 18 (67%, n = 27) isolates of Klebsiella spp.., 4 (80%, n = 5) isolates of Proteus spp., 1 (100%, n = 1) of isolated Pseudomonas aeruginosa and 6 (18%, n = 34) of E. coli found were resistant to at least 1 among the tested antibiotics. E. coli had an 83% higher proportion of multi-drug resistance (MDR) than Klebsiella spp.., which had 68.5%, and no MDR was shown by P. aeruginosa isolates. Among the 20 bacterial isolates of antibiotic-resistant genes, showed that E. coli harboured 39%, followed by 22% of Klebsiella spp. Eleven (11) isolates of these 20 (55%) contained sulphonamides resistant genes: Sul 1 (n = 4) and Sul 2 (n = 7). Ten (10) isolates (50%) contained the tetracycline- resistant genes in which 4 isolates showed the Tet A, Tet B – 1 and 5 isolates contained Tet D. β-lactamases (bla CTX-M and bla SHV) were found in 7 isolates (35%). The existence of these antibiotic-resistant species in the urban receiving and wastewater presents a threat of transmission of diseases to humans and animals that are not cured by the existing medications, jeopardizing public health safety.
Sanitary practices and occurrence of zoonotic conditions in cattle at slaughter in Morogoro municipality, Tanzania: implications for public health
(Tanzania Journal of Health Research, 2012-04) Komba, Erick V.G; Komba, Ewaldo V; Mkupasi, Ernatus M; Mbyuzi, Albano O; Luwumba, Denice; Busagwe, Zablon; Mzula, Alexanda
As meat consumption is increasing worldwide to cover for protein demands, also raise concerns and challenges regarding meat hygiene and safety. The current one year follow up study aimed at investigating on sanitary practices and occurrence of zoonotic conditions, during post- mortem examination, in cattle at slaughter in Morogoro Municipality abattoir. Sanitary practices were assessed through direct observation where as routine post-mortem inspection procedures were employed to detect zoonotic conditions in cattle at slaughter. During the study period a total of 30,713 cattle were slaughtered and inspected at the abattoir. Results revealed poor hygienic practices at the level of abattoir surrounding, the slaughter operation area, personnel as well as meat vans. Whole carcasses, lungs, livers, hearts and heads were condemned due to zoonotic conditions at rates of 0.026%, 1.96%, 1.61%, 0.02% and 0.21% respectively. Bovine tuberculosis, Cysticercus bovis cysts, fasciolosis and hydatidosis were the responsible zoonotic conditions for the condemnations. Bovine tuberculosis was a leading zoonotic cause of condemnations accounting for 95.7% of lungs and 100% of all head and carcass condemnations. Cysticercus bovis cysts were ranking the second in serving as causes of condemnations closely followed by fasciolosis and lastly hydatidosis. Occurrence of disease conditions with zoonotic implication in cattle at slaughter, meant for human consumption, may pose significant economic and public health risks to especially disaster-prone marginalized communities. Thus, there is a need to introduce appropriate control measures of livestock diseases to minimize the rate of infection; and eventually reduce economic losses and safeguard public health. _____________________________________________________________________________
Use of molecular methods to detect shedding of mycobacterium bovis in cattle faeces and milk
(Sokoine University of Agriculture, 2015) MALAKALINGA,JOSEPH
Bovine tuberculosis (BTB) is a chronic bacterial disease caused by Mycobacterium bovis. It affects cattle and occasionally other animals and human. Several techniques exist for detection of BTB in animals. In Tanzania, Single Intradermal Comparative Tuberculin Test (SC1TT) and abattoir meat inspection are the commonly used methods for screening of BTB. This study has used molecular biology method namely; RD4 Real time PCR (RD4 Rt PCR) to detect shedding M. bovis in milk and faecal samples from cattle tested by SCITT and Bovigam test. The study has also determined the detection limit of Immunomagnetic capture (IMC) and Centrifugation methods of M. bovis cells in spiked milk. A total of 63 cattle dairy form LITA farm Morogoro were tested for BTB with SCITT and Bovigam test. Faecal and milk samples-were collected and RJD4 Rt PCR was used to detect M. bovis DNA. BTB prevalence detected by SCITT and Bovigam was 3.1% and 3.1% respectively and BTB prevalence detected by RD4 Rt PCR in milk and faeces was 36.1% and 9.5% respectively. The kappa value between the SCITT and Bovigam was 1 and between shedding of M. bovis in milk and faeces detected using RD4 Rt PCR was 0.07. The detection limit of IMC and centrifugation coupled with Real time PCR ranges from 100 to 1 000 M. bovis cells per 500 pl milk and 10 to 100 M. bovis cells per 500 pl milk sample. High number of cattle was detected by Real time PCR to have BTB compared to SCITT or Bovigam. The confirmation of M. bovis in milk indicates potential root of transmission of M. bovis from cow to calf also to human who consume raw milk. Moreover, confirmation of M. bovis in feces indicates possible contamination of cattle carcasses during slaughter process. The study proposes that in order to improve BTB diagnosis for controlling and management of BTB, both conventional, SCITT or Bovigam and molecular methods in feces and milk need to be deployed in parallel but considering their own merits like cost and repeat access to animals.
Molecular investigation of multiplicity of infections and drug resistance to sulphadoxine-pyrimethamine (sp) in plasmodium falciparum malaria in Mlimba, Tanzania
(Sokoine University of Agriculture, 2004) MBUGI,ERASTO
The study was aimed at molecular investigation of multiplicity of infections and drug resistance to sulphadoxine-pyrimethamine (SP) in Plasmodium falciparum malaria. This molecular epidemiological study involved 141 blood samples from patients aged less than five years from malaria-endemic Mlimba division of Kilombero District, Morogoro, south eastern Tanzania. Blood samples were collected on filter papers (3MM Whatmann) and parasite DNA was extracted by Chelex technique. Molecular analysis on the merozoite surface protein 2 (MSP2), dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) was based on polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) of PCR products (PCR-RFLP). These techniques made it possible to determine the multiplicity of infections and SP resistance-associated point mutations anticipated at sorting out recrudescence from new infections. The commonly reported point mutations occurring at codons 51, 59, 108 and 164 in the DHFR and codons 437, 540 and 581 in the DHPS domains were investigated. The results showed the multiplicity of infection array of single to six infections per patient with an average multiplicity of 2.58 infections per patient. Fifty-one patients possessed single alleles of either allelic families of the MSP2 gene in PCR-RFLP successful samples. Double, triple and multiple infections were detected in 37.7%, 11.9% and 5.9% of patients, respectively. Regarding drug resistance molecular markers, 66.9% carried mutations at codon 108, 62.7% at codon 51 and 48.8% at codon 59 of DHFR domain. Fifty-six (43.7%) of samples carried mutations at codon 437, 39.2% at codon 540 and 0.8% at codon 581 on the DHPS domain. Proportions of mixed variants in the DHFR domain ranged from 0 - 21.5% and 0.8 - 6.3% in the DHPS domain. About 44 (36.4%) of isolatesiii harboured triple mutant DHFR genotypes, whereas quintuple mutation was observed in 24 (19.8%) of isolates. Ten (8.3%) isolates possessed at least double DHFR and double DHPS mutants. This study found a high proportion of SP resistance- associated point mutations in Mlimba two years after deployment of SP as a first-line antimalarial drug in Tanzania. However, the adequate clinical response (81.1%) observed clinically reflects the role of semi-immunity component in the study population. This implies that used molecular markers for monitoring drug resistance, be done simultaneously with studies on confounding factors pertaining to development of resistance against SP in falciparum malaria. The extensive use of antifolates other than SP for treatment of infections other than malaria is a probable candidate for potentiating selection of mutations ascribed to SP resistance. The SP resistance potential detected in this study, caution on its useful therapeutic life as an interim first-line drug against malaria in Tanzania
The role of rodents in the maintenance of the east African tick-borne relapsing fever aetiological agent, Borrelia duttonii
(Sokoine University of Agriculture, 2003) JESSEY,PAX
A total of 250 rodents, 251 adult and nymph ticks and seven human blood samples were collected from Mvumi township in Dodoma region, Tanzania, between November, 2001 and February, 2002, and analysed for the presence of the tick-borne relapsing fever agent (TBRF), Borrelia duttonii. Cultures of the spirochetes were made in Barbour-Stoenner-Kellys (BSK-II) medium, and molecular characterization of the spirochetes was done by polymerase chain reaction (PCR). Spirochete cultures were successfully grown from two out of the seven human blood samples. No spirochetes grew in either of the cultures of the rodent blood or the tick haemolymph and crushed tick samples. These samples were negative for spirochetes by staining and direct microscopy. PCR detected Borrelia DNA from two of the seven human blood samples, and from one of either rodent (Rat t us rattus), and tick samples. This is the first study on the possibility of rodents playing a role in the transmission of Borrelia spp in Tanzania. The detection of Borrelia DNA in rodents originating from this TBRF endemic area suggests the possibility of rodents playing a role in the maintenance of the TBRF agent, B. duttonii. Since it is generally accepted that only humans are the reservoirs of B. duttonii, this study calls for further investigation to determine the importance of commensal rodents and other mammals in the epidemiology of relapsing fever in Tanzania.
The distribution of contagious caprine pleuropneumonia in selected areas of Tanzania
(Sokoine University of Agriculture, 2005) KIMARYO,STEPHEN JAMES
A study was carried out to establish the distribution of Contagious Caprine Pleuropneumonia (CCPP) in Iringa, Mpwapwa and Kilosa districts, Tanzania. Information on the history of outbreaks was collected and clinical examination of goats with respiratory disease was conducted. Some typical cases were sacrificed for gross pathological evaluation. A total of 1247 serum samples (including 8 from sheep) were collected for serological analysis using the latex agglutination test (LAT). Nasal swab (57), lung (13), bronchial lymph node (13) and pleural fluid (6) samples were collected for microbiological culture and isolation of Mycoplasma capricoluni subsp. capripneiunoniae (M. capripneiunoniae') using a Ilayflick-based medium enriched with sodium pyruvate and containing 25% serum (H25P medium). Some samples were also cultured on a commercial freeze-dried CCPP diagnostic medium. Mycoplasma isolates on H25P medium were identified using the disc growth inhibition test while those on CCPP diagnostic medium were identified on the basis of their growth and colonial characteristics. All the sick and sacrificed goats showed clinical signs and post mortem features that were highly suggestive of CCPP. In Iringa district, out of the 250 goat sera from Mahenge division, 126 (approx. 50%) were positive for antibodies against M. capripneiunoniae, whereas of the 250 sera from Idodi division, 115 (46%) were seropositive. In Mpwapwa district, out of 301 analysed goat sera from Kibakwe division, 152 (approx. 50%) were seropositive compared to 47 (approx. 47%) of the 99 sera from Rudi division. Out of eight sheep sera, which were collected from Mpwapwa district, three (38%) had antibodies against M. capripneiunoniae. In Gairo division (Kilosa district), 339 goat sera were screened and 253 (approx. 75%) were seropositive. M. capripneiunoniaeiii was isolated from specimens from all the study districts. The results of this study indicate that the suspected outbreaks in the study areas were true CCPP. This provides additional information on the distribution of the disease in the country. The observation of characteristic colonics of M. capripneumoniae on the CCPP diagnostic medium demonstrates the latter’s potential in the field investigations of suspected CCPP outbreaks. The demonstration of M. capripneumoniae antibodies in sheep probably suggests that sheep are also susceptible to infection with the mycoplasma and may play a role in the epidemiology of CCPP. However, this aspect needs further investigation especially in pastoral and agro-pastoral systems where goats and sheep are often reared together.
Studies on canine transmissible venereal tumour of dogs in Mvomero and Morogoro municipality, Tanzania
(Tanzania Veterinary Association, 2018) Ishengoma, V. L.; Ndossi, D. G.; Nonga, H. E.
Canine transmissible venereal tumour (CTVT) is a contagious tumour that is naturally transmitted between dogs by the allogeneic transfer of living tumour cells during coitus. A cross-sectional study was conducted in Mvomero and Morogoro Municipality between September and November 2017 in order to determine the prevalence of CTVT and level of people’s awareness on the disease. The knowledge and interventions in reference to CTVT were evaluated using a structured questionnaire, whereas the status of the disease in animals was investigated through clinical examination. A total of 200 respondents were interviewed and 300 dogs were examined. Results on questionnaire showed that, most of the respondents had their dogs managed freely as stray dogs. Majority of the dog owners had one to five dogs and with no controlled breeding. It was further established that majority of the respondents knew CTVT as a disease of bleeding in dogs and had seen dogs affected by the disease suggesting that the disease is common in the study areas. Nevertheless, the real cause and treatment was not clear to most of the dog keepers. Based on clinical examination of dogs, the prevalence of CTVT in dogs was 12%, with Mvomero district having more cases of CTVT, 23 (15.4%) than Morogoro Municipality which had 13 (8.6%). In Mvomero district, Dakawa ward had the highest number of CTVT cases 12 (8.1%). Furthermore, it was found that male dogs were more affected by CTVT (15.3%) as compared to female dogs (8.7%). This study shows that magnitude of CTVT is high in the study area and insufficient knowledge and misconception on clinical presentation, spread, and treatments of the disease prevail. Therefore deliberate measures aimed at minimizing the problem need to be taken.
Effect of pyriproxyfen and ivermectin on survival and reproductive perfomance of plague flea vectors, xenopsylla cheopis
(Sokoine University of Agriculture, 2023-11) Mwakalinga, Nicolaus Anania
EXTENDED ABSTRACT One of the primary carriers of plague in many tropical and subtropical regions of the world is Xenopsylla Cheopis. Targeting flea vectors by sprinkling or dusting homes and surroundings with chemical insecticides is the primary method for controlling plague. However, the likelihood of insecticide resistance has increased because to the prolonged use and excessive reliance on chemical insecticides. Ivermectin and pyriproxyfen, which target both endoparasites and ectoparasites, will limit their actions and reduce their susceptibility to resistance. These substances have however not tested against plague fleas. The objectives of this study were to evaluate the effects of pyriproxyfen and ivermectin on reproduction and survival, as well as the viability of incorporating them into the current management methods. Two experimental designs were used; the first exposure to pyriproxyfen was investigated for its efficacy against adult, fecundity, and larval stages of the oriental rat flea. The contact bioassays against both the larval and adult stages of fleas conducted through series of laboratory experiments. In adult fleas, treatment and controls groups were tested in four replicates while larvae were six replicates. Exposure time of pyriproxyfen for adult fleas were 30 minutes and none for larvae Twelve rats were used in total for the second exposure method of the ivermectin and pyriproxyfen . Four rats were given 0.2 ml of ivermectin, four were given 0.3 g of pyriproxyfen powder, and four were left untreated. The adult fleas were exposed for 12 hours, and 10 days of observation followed. The survival curve of adult fleas was produced after data analysis using the R software. Additionally, the least square method was used to calculate the impact of pyriproxyfen and ivermectin on adult mortality. The survival rate of adult Xenopysylla cheopis fleas in a treatment group shown to be 100% at day 0. As time passed, there was a decreasing chance that the treated group would survive, and by day six, every flea in the treated group had died (P=0.0313). In comparison to the control group, the treatment group significantly produced less eggs (<0.0001). In the treatment group of flea larvae, ii 90% of the larvae died by day eight, and by day 20 of monitoring and observation, there were no cocooned flea larvae. 98% of the larvae in a control group survived and 60% of them formed cocoons. According to the research, adult fleas, egg viability, egg laying, and larval growth are all affected when 2g of pyriproxyfen mixed with sand and dried cattle blood powder is directly applied to them. Pyriproxyfen alone was considerably less toxic to adult fleas during a period of 24 hours, and mortalities began from day 2 and increased. However, similar hormone with other exposure methods in conjunction with ivermectin in action have shown that this is not the case. Pyriproxyfen was very effective in day four using the least square method, with an LS mean of 3.75 and a 0% egg-laying rate. Maximum mortalities were achieved at day five with an LS mean of 4.5 and a P-value of (0.0001), and 5% less eggs were deposited by adult fleas that were exposed to ivermectin. The combination of pyriproxyfen and ivermectin was effective against adult fleas, with the largest mortalities occurring on days three and four with LS Means of 4.75 and 5, respectively, and no eggs being deposited during the course of the monitoring period of ten days. This combination of pyriproxyfen and ivermectin may be utilized to better control the plague in endemic areas and as flea vector control agents.
Respiratory syndrome in relation to occupational pesticide exposure among farmworkers: A case study of Kilimanjaro and Arusha regions, Northern Tanzania
(Sokoine University of Agriculture, 2023-09) Owisso Rose Donati
In developing countries, the use of pesticides has been increasing due to an increase in new pests and diseases. This has resulted in the use of highly hazardous pesticides (HHPs) with the potential of causing health risks including respiratory syndromes and sometimes deaths to humans. The World Health Organization (WHO) estimated three million cases of acute pesticide poisoning and 220,000 deaths annually worldwide. Despite the significance of pesticide exposure to pesticides, studies on long health effects associated with pesticide exposure among the working population are limited in low- and middle-income countries (LMICs). A previous study conducted among farmworkers in Arumeru District of Tanzania revealed health problems resulting from Acute Pesticide Poisoning (APP) were related to other diseases such as malaria and pneumonia that lead to misdiagnosis and underreporting of the health challenges resulting from exposure to occupational pesticides. Thus, the current study aimed at investigating the association between occupational exposure to pesticides and respiratory syndromes among farmworkers in Arumeru and Moshi Districts in Arusha and Kilimanjaro regions. A cross-sectional study involving both semi- structured questionnaire and Key informative interview data collection methods was used to assess the respiratory health challenges experienced by farmworkers when applying either synthesized pesticides or organic inputs to either coffee or flowers farm. Key Informant Interviews (KIIs) was used to gain a deeper understanding of the farmworkers’ awareness of occupational exposure to pesticides and organic inputs in relation to the respiratory syndrome. The study participants included both male and female farmworkers of between 18 and 48 years of age working in flower and coffee plantation farms in Arumeru and Moshi Districts. 194 non-organic and 195 organic farmers who were directly engaged in agricultural activities were randomly selected from their farms to participate in the study. Among 389 study participants, 24 farmworkers were purposively selected to participate in the key informative interview (KII). Supporting staff such as Human Resource Officers found in the study farms but not engaged directly in agricultural activities were excluded from this study. adj. OR (95% CI)4.58(1.68, 12.54), 4.74 (1.83, 12.29) and 6.30 (1.29,30.72] . In the KII, it was reported that pesticide mixers and sprayers were using person protective equipment, taking baths and changing clothes after farm work while other farmworkers such as flower pruners, flower graders and coffee pickers were not using protective equipment. The visited coffee organic farm was not equipped with sanitary facilities and farmworkers were not protecting themselves from direct contact with the organic inputs. The results in the quantitative study indicate that pesticide mixers and sprayers in flower farms were significantly associated with cough, rhinitis and wheezing, [ respectively. Moreover, there was a decreasing risk of cough and rhinitis for flower farmworkers taking baths after work, [adj. OR (95% CI) 0.33 (0.16, 0.68) and 0.44(0.26, 0.75)] results showed the association between respiratory syndrome and occupational exposure to pesticides among to chemical pesticides. There was an inconclusive result on Furthermore, non-organic farmworkers who were at high risk of exposure the association between respiratory syndrome and organic inputs given that other causes such as allergies were not investigated.
Hatching of artemia franciscana and it’s performance in fertilized ponds
(Sokoine University of Agriculture, 2024-05) Jacob, Augustino Tegemea
This study was conducted to assess the general performance of Artemia franciscana from saltworks in Tanga, Tanzania. The study aimed to determine Artemia cysts’ biometry and hatching efficiency, and effect of pond fertilization on growth performance and nutritional composition of Artemia. For the study on biometry and hatching efficiency, Artemia cysts were collected from salt farms in Tanga, Tanzania, using a 100-150 mesh net. Then the cysts were processed and packed in airtight containers. In the laboratory, the diameter of each cyst was measured from a sub sample of 200 cysts and another sub-samples were incubated in beakers at 28 °C, 35 ppt, and a pH of 8. After 24 hours, newly hatched nauplii were moved in triplicate to the culturing tanks, where they were cultured for 15 days while being fed microalgae (Nannochloropsis oculate). As a reference, the Vinh Chau Artemia cyst strain (from Vietnam) was used as control. The findings showed that Artemia cyst from Tanga had a higher value of capsulated cyst diameter (213.4μm) and chorion thickness (9.7μm) compared to Vinh Chau Artemia cysts (208.3 μm; 8.3 μm) respectively. Also, a higher hatching percentage and efficiency was observed in Vinh Chau Artemia cyst compared to Tanga (p < 0.05). However a higher growth performance and survival percentage (74.56%) were observed in Tanga Artemia strain compared to Vinh Chau Artemia strain (53.85%) which is very promising. Hence, Tanga Artemia strain showed good quality hence its prospects to production in pond. However, the study on the effects of pond fertilization, examined the growth performance and nutritional composition of Artemia. At 28 °C, 35 ppt, and a pH of 8, six buckets each holding 20 liters of water were used to hatch a total of 30g cysts. The newly hatched nauplii were then inoculated in triplicates into the fertilized and non-fertilized ponds, where they were cultured for 28 days at a density of 100 nauplii/litre. The results on Artemia’s growth performance and nutritional composition were significantly greater in fertilized ponds (p<0.05). Phytoplankton communities were also more abundant in fertilized ponds compared to non-fertilized ponds. All the environmental parameters monitored were within the recommended range for example the mean salinity was above 70ppt. The findings from this study suggested that pond fertilization is of great importance for quality and optimal production of Artemia in ponds. The results of this study lead to the conclusion that Tanga cysts exhibit good biometric characteristics as well as good growth performance when exposed to pond fertilization. As a result, we recommend further research in order to enhance more traits of the local Artemia breed in pond production.
Estimating risk of introduction of ebola virus disease from the democratic republic of Congo to Tanzania: a qualitative assessment
(MDPI, 2022-02-11) Rugarabamu Sima; Mwanyika Gaspary O.; Misinzo Gerald; Mboera Leonard E. G.; George Janeth; Mbanzulu Kennedy M.
Between April 2018 and November 2020, the Democratic Republic of Congo (DRC) experi- enced its 11th Ebola virus disease (EVD) outbreak. Tanzania’s cross-border interactions with DRC through regular visitors, traders, and refugees are of concern, given the potential for further spread to neighboring countries. This study aimed to estimate the risk of introducing EVD to Tanzania from DRC. National data for flights, boats, and car transport schedules from DRC to Tanzania covering the period of May 2018 to June 2019 were analyzed to describe population movement via land, port, and air travel and coupled with available surveillance data to model the risk of EVD entry. The land border crossing was considered the most frequently used means of travel and the most likely pathway of introducing EVD from DRC to Tanzania. High probabilities of introducing EVD from DRC to Tanzania through the assessed pathways were associated with the viability of the pathogen and low detection capacity at the ports of entry. This study provides important information regarding the elements contributing to the risk associated with the introduction of EBV in Tanzania. It also indicates that infected humans arriving via land are the most likely pathway of EBV entry, and therefore, mitigation strategies including land border surveillance should be strengthened.

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