scholarly journals Trends in the control of theileriosis in sub-Saharan Africa : tick-borne diseases

2009 ◽  
Vol 76 (1) ◽  
Author(s):  
D. McKeever
Keyword(s):  
Genotypic Diversity ◽  
Treatment Method ◽  
Sub Saharan Africa ◽  
Cold Chain ◽  
Theileria Parva ◽  
Protective Mechanisms ◽  
Subunit Vaccines ◽  
Substantial Progress ◽  
Sub Saharan ◽  
Infection And Treatment Method

The declining efficacy of acaricide treatment as a means of reducing the prevalence of Theileria parva infections in sub-Saharan Africa has intensified efforts to achieve control through immunization of susceptible cattle. The infection and treatment method of immunization has enjoyed a resurgence with the availability of more effective cold chain facilities, although concerns remain regarding the possibility of vaccine strains spreading in local tick populations. In addition, an in-depth understanding of protective mechanisms deployed by immune cattle and the antigens targeted by them has led to substantial progress in the development of candidate subunit vaccines against both sporozoite and schizont stages of the parasite. The likely success of these vaccines, as well as infection and treatment immunization, will ultimately depend on the extent to which they disturb the endemic status of the parasite. These issues are discussed in the light of recent information on the genotypic diversity of T. parva in the field and the extent to which this is compromised by the immune response.

scholarly journals Occurrence of Theileria parva and other haemoprotozoa in cattle at the edge of Hluhluwe-iMfolozi Park, KwaZulu-Natal, South Africa

2010 ◽  
Vol 81 (1) ◽  
Author(s):  
S. B.A.S. Yusufmia ◽  
N. E. Collins ◽  
R. Nkuna ◽  
M. Troskie ◽  
P. Van Den Bossche ◽  
...  
Keyword(s):  
South Africa ◽  
Buffy Coat ◽  
Babesia Bovis ◽  
Sub Saharan Africa ◽  
Significant Finding ◽  
Theileria Parva ◽  
Mortality And Morbidity ◽  
Kwazulu Natal ◽  
Pcr Rflp ◽  
Sub Saharan

Theileria parva, the most important bovine theilerial species in sub-Saharan Africa, causes widespread mortality and morbidity in endemic areas. A survey was conducted using buffy-coat specimens from 60 apparently healthy adult communally herded Nguni-type cattle at the northeastern edge of the Hluhluwe-iMfolozi Park to determine, by means of PCR and Reverse Line Blot (RLB) hybridisation, the occurrence of Theileria and Babesia species. The presence of Trypanosoma species was determined using PCR-RFLP. Results showed that 6.7 % of the specimens were positive for Theileria parva. This significant finding suggests that cattle in South Africa, and not only African buffaloes (Syncerus caffer), may be subclinical carriers of T. parva. Other species identified were T. mutans (83.3 %), T. velifera (70.0 %), Theileria sp. (sable) (46.8 %) and T. taurotragi (1.7 %). Two specimens (3.3 %) were positive for Babesia bovis and single specimens (1.7 %) positive for B. bigemina and B. rossi, respectively. Mixed infections, of up to 4 species, were common (65.0 %). Only 1 specimen was found to be positive for Trypanosoma vivax, and 2 for T. theileri, of which only the first species is pathogenic.

scholarly journals Production, Utilization and Nutritional benefits of Orange Fleshed Sweetpotato (OFSP) Puree Bread: A Review

2018 ◽  
Vol 6 (3) ◽  
pp. 644-655 ◽  
Author(s):  
JOSHUA OMBAKA OWADE ◽  
GEORGE OOKO ABONG ◽  
MICHAEL WANDAYI OKOTH
Keyword(s):  
Vitamin A Deficiency ◽  
Scientific Progress ◽  
Food Product ◽  
Production Costs ◽  
Sub Saharan Africa ◽  
Cold Chain ◽  
Cereal Product ◽  
Sub Saharan ◽  
Bread Production ◽  
Nutritional Benefits

Bread though an exotic food product in sub-Saharan Africa, has been an important cereal product consumed by most individuals among the vast Sub-Saharan African population. Bread formulations in both the local and industrial production have evolved. The latest and emerging technology in bread formulation involve the incorporation of orange-fleshed sweetpotato (OFSP) puree. OFSP puree-based bread is commercially available across sub-Saharan Africa (SSA) and is being promoted due to the potential nutritional benefits that it possesses. Together with OFSP flour based bread, OFSP puree based bread serves as a good food vehicle for β-carotene; this serves to alleviate vitamin A deficiency (VAD) especially among the vulnerable population in SSA. The production of OFSP puree based bread has so far been relying on fresh OFSP puree or cold-chain stored OFSP puree. However, this has presented economic challenges and problems to the sustainability and expansion in OFSP puree bread production. Cold chain stored OFSP puree is capital intensive and has inconsistent supply. With the development of shelf-storable preservative treated OFSP puree, most of these challenges will be overcome without undoing the currently harnessed benefits. The use of OFSP puree in bread baking can then be expanded easily at minimal production costs and maximum retention of nutritional quality. Therefore, the use of the shelf-storable OFSP puree in bread baking needs to be evaluated further to present a substantiated case for its use. The current review has been developed with focus on the scientific advances in the production of OFSP puree based bread from both historical and a forecast perspective. The scientific progress and breakthroughs in the use of OFSP puree in bread are critically reviewed.

scholarly journals STATUS, CHALLENGES AND OPPORTUNITIES OF THE COLD CHAIN SYSTEM IN KENYA: THE CASE OF THE FISHERIES SECTOR IN LAMU AND MOMBASA COUNTIES

2022 ◽  
Vol 1 (2) ◽  
pp. 28-46
Author(s):  
Sofia Tumaini Kabibi ◽  
Benards Okeyo ◽  
M. H. Khalil Timamy
Keyword(s):  
Sub Saharan Africa ◽  
Cold Chain ◽  
Primary Data ◽  
Unique Contribution ◽  
Fishing Sector ◽  
Challenges And Opportunities ◽  
The Status ◽  
Fish Catch ◽  
Sub Saharan ◽  
Study Sites

Purpose: This study examined the status, challenges and opportunities of the fishing sub-sector in Mombasa and Lamu counties in Kenya. The study examined the various opportunities cold chain have in development of the fisheries sector. The study zeroed on factors like the economic, administrative, financial, technological and cultural attributes that influence the efficiency of the cold chain. Methodology: Literature reviewed showed that shortage of reliable and adequate cold chain facilities in sub-Saharan Africa is one of the main causes of losses of perishable products however there’s little documentation of the study on the status, challenges and opportunities of cold chain technologies in the fishing sector in Kenya.  The study adopted a descriptive research design. The study focusses on 2 counties in Coastal Kenya i.e. Mombasa and Lamu Counties. The justification for selecting the 2 sites was that Lamu fisheries industry is extensive and highly developed, Lamu receives the highest number of fish harvest. Primary data was obtained through questionnaires and personal interviews. The personal interviews took 5 days in Mombasa and 5 days in Lamu. The data was analyzed using the Statistical Package for the Social Sciences; SPSS version 20. Results: The main result of the study was showed that cold chain is widely used and required in the advancement of fishing in all the study sites. The study also revealed that Lamu County is more dependent on cold chain for fishing to earn profit for the sector as it final market is Mombasa a distance of over 200km away. The needs of the type, capacity and partnership is different from one Beach Management Unit to the other. This is primarily due to factor such fish catch, governance dynamics, access and affordability of cold chain technology and distance to the market. Unique contribution to theory, practice and policy: The study indicated that there has been deliberate effort by the two tier government – National and County to invest in Cold chain however this has been faced with myriad challenges where this installed equipment are either not operating efficiently or have stalled. The study indicated and showed that there needs to be systematic approach when selecting and managing cold chain equipment in the fishing sector.

scholarly journals Flow Cytometric Analysis of the Cytotoxic T-Cell Recall Response to Theileria parva in Cattle Following Vaccination by the Infection and Treatment Method

2021 ◽  
Vol 8 (6) ◽  
pp. 114
Author(s):  
Mahmoud M. Elnaggar ◽  
Donald P. Knowles ◽  
William C. Davis ◽  
Lindsay M. Fry
Keyword(s):  
T Cells ◽  
Cd8 T Cells ◽  
Vaccine Development ◽  
Treatment Method ◽  
Theileria Parva ◽  
Recall Response ◽  
Infected Cells ◽  
Infection And Treatment Method ◽  
Ctl Activity ◽  
Stimulation Of

The apicomplexan hemoparasite, Theileria parva, causes East Coast fever (ECF), a frequently fatal disease of African cattle. Vaccine development has been impeded by incomplete understanding of protective immunity following natural exposure or the infection and treatment method (ITM) of immunization. This is attributable to a paucity of methods to characterize the memory T-cell repertoire following infection. To overcome this impediment, assays developed to study the immune response to other intracellular pathogens were adapted for use in studies with T. parva to enable definition of the phenotype and function of effector T cells in T. parva-immune cattle, facilitating vaccine development. As reported herein, stimulation of peripheral blood mononuclear cells (PBMC) from ITM-immunized steers with irradiated, autologous, T. parva-infected cell lines elicited a proliferative recall response comprised of CD45R0+/CCR7− CD4+ and CD8+ T cells. Subsequent co-incubation of stimulated cultures with infected cells demonstrated the presence of cytotoxic T cells (CTLs) with the ability to kill infected cells. Comparison of CTL activity in cultures depleted of CD4+ or CD8+ T cells demonstrated CTL activity was primarily attributed to CD8+ T cells. Importantly, stimulation of PBMC from vaccinated steers always elicited proliferation of CD4+ and CD8+ T cells. This was the first important observation obtained from the use of the assay described herein.

Theilerial parasites isolated from carrier cattle after immunization with Theileria parva by the infection and treatment method

Parasitology ◽  
1989 ◽  
Vol 99 (1) ◽  
pp. 139-147 ◽  
Author(s):  
A. C. Maritim ◽  
A. S. Young ◽  
A. C. Lesan ◽  
S. G. Ndungu ◽  
J. J. Mutugi ◽  
...  
Keyword(s):  
Cell Culture ◽  
Monoclonal Antibody ◽  
Treatment Method ◽  
Rhipicephalus Appendiculatus ◽  
Carrier State ◽  
Concomitant Treatment ◽  
Theileria Parva ◽  
Experimental Animals ◽  
Cell Culture Isolation ◽  
Infection And Treatment Method

SUMMARYGroups of cattle were immunized with 10−2 dilutions of sporozoite stabilates of Theileria parva lawrencei derived from African buffaloes either alone or in combination with Theileria parva parva derived from cattle and concomitant treatment with either long or short-acting formulations of oxytetracyline. At 90 or 120 days after infection, uninfected Rhipicephalus appendiculatus nymphal ticks were applied to individual immunized cattle and the resultant adults ticks were applied to individual susceptible cattle. Theilerial infection developed from ticks fed on 6 out of 11 animals investigated for evidence of a carrier state. Two additional animals were shown by cell-culture isolation to have persistent theilerial infections. Nine cattle infected with the parasites from carrier animals were treated with parvaquone and 7 recovered. These recovered cattle were then challenged with the original immunizing stabilates at 10° dilution together with the original immunized and carrier cattle. Six out of 7 cattle which had recovered from carrier-derived infection succumbed to this challenge and died but none of the original immunized cattle showed theilerial reactions. When a carrier-derived sporozoite stabilate was used to challenge cattle immune to the original immunizing parasite, they proved to be immune. Cattle immune to the carrier-derived parasites were all immune to challenge with the original parasite. A monoclonal antibody profile aginst T. parva schizonts isolated by cell culture from samples of the experimental animals did not appear to be sensitive enough to determine the antigenic differences between the carrier-derived parasite and the original immunizing parasite. Indications are that the carrier state is not likely to produce new antigenic strains which would be dangerous to immunized cattle.

scholarly journals Development of a yeast-based vaccine for Theileria parva infection in cattle

2021 ◽  
Author(s):  
Shan Goh ◽  
Jeannine Kolakowski ◽  
Angela Holder ◽  
Mark Pfuhl ◽  
Daniel Ngugi ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Response ◽  
Sub Saharan Africa ◽  
Cytotoxic T Cell ◽  
Control Group ◽  
Theileria Parva ◽  
Serum Igg ◽  
Cell Immunity ◽  
Freeze Dried ◽  
Sub Saharan

AbstractEast Coast Fever (ECF), caused by the tick-borne apicomplexan parasite Theileria parva, remains one of the most important livestock diseases in sub-Saharan Africa with more than 1 million cattle dying from infection every year. Disease prevention relies on the so-called “Infection and Treatment Method” (ITM), which is costly, complex, laborious, difficult to standardise on a commercial scale and results in a parasite strain specific, MHC class I restricted cytotoxic T cell response. We therefore attempted to develop a safe, affordable, stable, orally applicable and potent subunit vaccine for ECF using five different T. parva schizont antigens (Tp1, Tp2, Tp9, Tp10 and N36) and Saccharomyces cerevisiae as an expression platform. Full-length native Tp2 and Tp9 as well as fragments of native Tp1 were successfully expressed on the surface of S. cerevisiae. In vitro analyses highlighted that recombinant yeast expressing Tp2 can elicit IFNy responses using PBMCs from ITM-animals, while Tp2 and Tp9 induced IFNy responses from enriched bovine CD8+ T cells. A subsequent in vivo study showed that oral administration of heat-inactivated, freeze-dried yeast stably expressing Tp2 increased total murine serum IgG over time, but more importantly, induce Tp2 specific serum IgG antibodies in individual mice compared to the control group. While these results will require subsequent experiments to verify induction of protection in neonatal calves, our data indicates that oral application of yeast expressing Theileria antigens could provide an affordable and easy vaccination platform for sub-Saharan Africa. Evaluation of antigen specific cellular immune responses, especially cytotoxic CD8+ T cell immunity in cows will further contribute to the development of a yeast-based vaccine for ECF.

Theilerial parasites isolated from carrier cattle afterimmunization with Theileria parva by the infection and treatment method

Parasitology ◽  
1989 ◽  
Vol 99 (S1) ◽  
pp. 139-147
Author(s):  
A. C. Maritim ◽  
A. S. Young ◽  
A. C. Lesan ◽  
S. G. Ndungu ◽  
J. J. Mutugi ◽  
...  
Keyword(s):  
Cell Culture ◽  
Monoclonal Antibody ◽  
Treatment Method ◽  
Rhipicephalus Appendiculatus ◽  
Carrier State ◽  
Concomitant Treatment ◽  
Theileria Parva ◽  
Experimental Animals ◽  
Cell Culture Isolation ◽  
Infection And Treatment Method

Groups of cattle were immunized with 10−2 dilutions of sporozoite stabilates of Theileria parva lawrencei derived from African buffaloes either alone or in combination with Theileria parva parva derived from cattle and concomitant treatment with either long or short-acting formulations of oxytetracyline. At 90 or 120 days after infection, uninfected Rhipicephalus appendiculatus nymphal ticks were applied to individual immunized cattle and the resultant adults ticks were applied to individual susceptible cattle. Theilerial infection developed from ticks fed on 6 out of 11 animals investigated for evidence of a carrier state. Two additional animals were shown by cell-culture isolation to have persistent theilerial infections. Nine cattle infected with the parasites from carrier animals were treated with parvaquone and 7 recovered. These recovered cattle were then challenged with the original immunizing stabilates at 10° dilution together with the original immunized and carrier cattle. Six out of 7 cattle which had recovered from carrier-derived infection succumbed to this challenge and died but none of the original immunized cattle showed theilerial reactions. When a carrier-derived sporozoite stabilate was used to challenge cattle immune to the original immunizing parasite, they proved to be immune. Cattle immune to the carrier-derived parasites were all immune to challenge with the original parasite. A monoclonal antibody profile aginst T. parva schizonts isolated by cell culture from samples of the experimental animals did not appear to be sensitive enough to determine the antigenic differences between the carrier-derived parasite and the original immunizing parasite. Indications are that the carrier state is not likely to produce new antigenic strains which would be dangerous to immunized cattle.

scholarly journals Geospatial assessment of the voluntary medical male circumcision programme in Tanzania, 2011–2016

2019 ◽  
Vol 4 (6) ◽  
pp. e001922
Author(s):  
Hana Kim ◽  
Adam Branscum ◽  
F DeWolfe Miller ◽  
Diego F Cuadros
Keyword(s):  
Incidence Rate ◽  
Male Circumcision ◽  
Age Groups ◽  
Incidence Rates ◽  
Sub Saharan Africa ◽  
Voluntary Medical Male Circumcision ◽  
Cross Sectional ◽  
Medical Male Circumcision ◽  
Substantial Progress ◽  
Sub Saharan

IntroductionTanzania is one of the 14 priority countries in sub-Saharan Africa scaling up voluntary medical male circumcision (VMMC) for HIV prevention. In this study, we assessed the progress of VMMC by evaluating changes in the spatial structure of male circumcision (MC) prevalence and identifying age groups with low MC uptake.MethodsWe use data from two waves of the Demographic and Health Survey (DHS) conducted in Tanzania in 2011–2012 and 2015–2016. MC incidence rate was estimated using a method developed to calculate incidence rates from two successive cross-sectional surveys. Continuous surface maps of MC prevalence were generated for both DHS waves and compared with identified areas with high MC prevalence changes and high density of uncircumcised males.ResultsNational MC prevalence in Tanzania increased from 73.5% in 2011–2012 to 80.0% in 2015–2016. The estimated national MC incidence rate was 4.6 circumcisions per 100 person-years (py). The lowest circumcision rate was observed in males aged 20–24 years, with 0.61 circumcisions per 100 py. An estimated 1 567 253 males aged 15–49 years residing in low-MC prevalence areas were uncircumcised in 2015–2016.ConclusionTanzania has shown substantial progress in the implementation of VMMC. However, extensive spatial variation of MC prevalence still exists in the country, with some areas having an MC prevalence <60%. Here, we identified locations where VMMC needs to be intensified to reach the ~1.5 million uncircumcised males age 15–49 living in these low-MC areas, particularly for men aged 20–34.

Comparison of manual and homogenizer methods for preparation of tick-derived stabilates of Theileria parva: equivalence testing using an in vitro titration model

Parasitology ◽  
2005 ◽  
Vol 131 (1) ◽  
pp. 45-49 ◽  
Author(s):  
V. MBAO ◽  
N. SPEYBROECK ◽  
D. BERKVENS ◽  
T. DOLAN ◽  
P. DORNY ◽  
...  
Keyword(s):  
East Coast ◽  
Treatment Method ◽  
Rhipicephalus Appendiculatus ◽  
Equivalence Testing ◽  
Theileria Parva ◽  
Control Option ◽  
Infected Adult ◽  
Effective Doses ◽  
Infection And Treatment Method

Theileria parva sporozoite stabilates are used in the infection and treatment method of immunization, a widely accepted control option for East Coast fever in cattle. T. parva sporozoites are extracted from infected adult Rhipicephalus appendiculatus ticks either manually, using a pestle and a mortar, or by use of an electric homogenizer. A comparison of the two methods as a function of stabilate infectivity has never been documented. This study was designed to provide a quantitative comparison of stabilates produced by the two methods. The approach was to prepare batches of stabilate by both methods and then subject them to in vitro titration. Equivalence testing was then performed on the average effective doses (ED). The ratio of infective sporozoites yielded by the two methods was found to be 1·14 in favour of the manually ground stabilate with an upper limit of the 95% confidence interval equal to 1·3. We conclude that the choice of method rests more on costs, available infrastructure and standardization than on which method produces a richer sporozoite stabilate.

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