Browsing by Author "Misinzo, Gerald"

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A study of rift valley fever virus in Morogoro and Arusha regions of Tanzania - serology and farmers’ perceptions
(Taylor & Francis Group, 2015-11-18) Wensman, Jonas J; Lindahl, Johanna; Wachtmeister, Nica; Torsson, Emeli; Gwakisa, Paul; Kasanga, Christopher; Misinzo, Gerald
Introduction: Rift Valley fever (RVF) is a zoonosis primarily affecting ruminants, resulting in epidemic abortions, fever, nasal and ocular discharges, haemorrhagic diarrhoea, and a high mortality rate among young animals. Rift Valley fever virus (RVFV) is an arthropod-borne RNA virus occurring in epizootic periods associated with heavy rainfall. The last outbreak of RVF in Tanzania was in 2006 2007, resulting in severe economic losses and impaired food security due to greater number of deaths of livestock. The aim of this study was to investigate the presence of antibodies against RVFV in sheep and goats in two different regions of Tanzania during an inter-epidemic period (IEP). In addition, the perception of important diseases among livestock keepers was assessed. Material and methods: A cross-sectional serological survey was conducted in three purposively selected districts in Arusha and Morogoro regions of Tanzania. Serum samples from 354 sheep and goats were analysed in a commercial RVFV competitive ELISA. At the sampling missions, a questionnaire was used to estimate the socio-economic impact of infectious diseases. Results and discussion: In total, 8.2% of the analysed samples were seropositive to RVF, and most seropositive animals were younger than 7 years, indicating a continuous circulation of RVFV in the two regions. None of the livestock keepers mentioned RVF as an important livestock disease. Conclusions: This study confirms that RVFV is circulating at low levels in small ruminants during IEPs. In spite of recurring RVF outbreaks in Tanzania, livestock keepers seem to have a low awareness of the disease, making them poorly prepared and thus more vulnerable to future RVF outbreaks.
Aedes aegypti abundance, larval indices and risk for dengue virus transmission In Kinondoni district, Tanzania
(BMC, 2022) Ngingo, Baraka L; Mboera, Leonard E. G; Chengula, Augustino; Machelle, Ines; Makange, Mariam R; Msolla, Michael; Mwanyika, Gaspary O; Rugarabamu, Sima; Misinzo, Gerald
Background: Tanzania has experienced periodic dengue outbreaks with increased incidence since 2010. However, there is limited information on vector dynamics and transmission risk in most parts of the country. This study was conducted to determine Aedes mosquito abundance, larval indices and dengue virus infection rate as risk indicators for DENV transmission in Kinondoni district, Dar es Salaam, Tanzania. Methods: A cross-sectional study was conducted in three wards of Kinondoni district in Tanzania between Decem- ber 2019 and January 2020. In each ward, three streets were randomly selected for adult and immature mosquito sampling. The adult mosquitoes were collected using Mosquito Magnet traps, while mosquito larvae and pupae were inspected in water-holding containers in the selected household compounds. The detection of dengue virus (DENV) in female Aedes mosquitoes was done using a one-step reverse transcription–polymerase chain reaction (RT–PCR) method. Results: Of the 1416 adult female mosquitoes collected, Ae. aegypti accounted for 16.8% (n = 238). A total of 333 water-holding containers were inspected and 201 (60.4%) had at least an Aedes larvae or pupae. Water-holding containers supporting the breeding of Aedes larvae and pupae included discarded car tires, flowerpots and small and large plastic containers. The overall House Index, Container Index and Breteau Index were 55.1%, 60.4% and 114.2, respectively. None of the 763 female Aedes mosquitoes tested by RT–PCR was found to be infected with DENV. Conclusion: The presence and abundance Ae. aegypti mosquitoes and the large proportion of water-holding con- tainers infested with the mosquito larvae and pupae put residents of Kinondoni district at high risk of DENV trans- mission. Our findings emphasize the need for continuous mosquito vector surveillance and control to prevent the possibility of future DENV outbreaks in Tanzania.
Batrachochytrium dendrobatidis detected in Kihansi spray toads at a captive breeding facility (Kihansi, Tanzania)
(Inter Research [Commercial Publisher]) Makange, Mariam; Kulaya, Neema; Biseko, Emiliana; Kalenga, Parson; Mutagwaba, Severinus; Misinzo, Gerald
Batrachochytrium dendrobatidis detected in Kihansi spray toads at a captive breeding facility (Kihansi, Tanzania)
(Inter Research [Commercial Publisher], 2014-09-30) Makange, Mariam; Kulaya, Neema; Biseko, Emiliana; Kalenga, Parson; Mutagwaba, Severinus; Misinzo, Gerald
The chytrid fungus Batrachochytrium dendrobatidis (Bd) is the aetiological agent of amphibian chytridiomycosis, a disease associated with global amphibian population declines. In November 2012, mass mortalities of Kihansi spray toads Nectophrynoides asperginis were observed at the Kihansi captive breeding facility, located in the Udzungwa Mountains, Tanzania. Mortalities increased rapidly, and dead toads showed typical clinical signs of chytridiomycosis, including reddening of the skin that was especially evident on the toe pads. Treatment of toads with itraconazole rapidly reduced mortalities. Dead toads (n = 49) were collected and used to per- form Bd-specific polymerase chain reaction and subsequent nucleotide sequencing. All toads col- lected at the facility were positive for Bd. The obtained Bd 5.8S rRNA gene and flanking internal transcribed spacer regions (ITS1 and ITS2) were not 100% identical to any other Bd sequences in GenBank, but closely resembled isolates from Ecuador, Japan, USA, Brazil, Korea, and South Africa. To our knowledge, this is the first study reporting molecular characteristics of Bd isolated from the Udzungwa Mountains. Strict biosecurity measures at the breeding facility and in Kihansi spray wetlands where toads have been reintroduced have been implemented. Further studies on Bd epidemiology in the Udzungwa Mountains are recommended in order to understand its origin, prevalence, and molecular characteristics in wild amphibian populations. This will be important for conservation of several endemic amphibian species in the Udzungwa Mountains, which are part of the Eastern Arc Mountains, a global biodiversity hotspot.
Circulation of dengue serotype 1 viruses during the 2019 outbreak in Dar es Salaam, Tanzania
(Informa UK Limited, trading as Taylor & Francis Group.) Mwanyika, Gaspary O.; Mboera, Leonard E. G.; Rugarabamu, Sima; Makange, Mariam; Sindato, Calvin; Lutwama, Julius J.; Paweska, Janusz T.; Misinzo, Gerald
Crossing the line: seroprevalence and risk factors for transboundary animal diseases along the Tanzania-Zambia border
(Veterinary Epidemiology and Economics, a section of the journal Frontiers in Veterinary Science) Lysholm, Sara; Lindahl, Johanna F.; Munyeme, Musso; Misinzo, Gerald; Mathew, Coletha; Alvåsen, Karin; Dautu, George; Linde, Siri; Mitternacht, Lydia; Olovsson, Emelie; Wilén, Elsa; Berg, Mikael; Wensman, Jonas J.
Crossing the line: seroprevalence and risk factors for transboundary animal diseases along the Tanzania-Zambia border
(Veterinary Epidemiology and Economics, a section of the journal Frontiers in Veterinary Science, 2022) Lysholm, Sara; Lindahl, Johanna F.; Munyeme, Musso; Misinzo, Gerald; Mathew, Coletha; Alvåsen, Karin; Dautu, George; Linde, Siri; Mitternacht, Lydia; Olovsson, Emelie; Wilén, Elsa; Berg, Mikael; Wensman, Jonas J.
Transboundary pathogens pose a threat to livelihood security in countries such as Zambia and Tanzania. This study aimed to investigate the seroprevalence of peste des petits ruminants virus (PPRV), foot and mouth disease virus (FMDV), sheep and goat pox virus (SGPV), Rift Valley fever virus (RVFV) and Brucella spp. in sheep and goats along the Tanzania-Zambia border. Another aim was to assess the association between certain predictor variables and seroprevalence, focusing on trade and proximity to an international border, to a town and to the Tanzania-Zambia highway. During September-October 2018, 486 serum samples from small ruminants in Zambia and 491 in Tanzania were collected and analyzed using enzyme-linked immunosorbent assays (ELISA). A questionnaire focused on management strategies was administered to each household. The animal-level seroprevalence in Zambia was 0.21% [95% confidence interval (CI) (0.01–1.14) for PPRV, 1.03% (95% CI 0.33–2.39) for FMDV, 0% (95% CI 0–0.76) for SGPV, 2.26% (95% CI 1.14–4.01) for RVFV and 1.65% (95% CI 0.71–3.22) for Brucella spp.]. In Tanzania, animal-level seroprevalence was 2.85% (95% CI 1.57–4.74) for PPRV, 16.9% (95% CI 13.7–20.5) for FMDV, 0.20% (95% CI 0.01–1.13) for SGPV, 3.26% (95% CI 1.87–5.24) for RVFV and 20.0% (95% CI 14.5–26.5) for Brucella spp. For PPRV (OR 6.83, 95% CI 1.37–34.0, p = 0.019) and FMDV (OR 5.68, 95% CI 1.58–20.3, p = 0.008), herds situated more than 30 km from an international border were more likely to be seropositive, while being located 10–30 km (OR 4.43, 95% CI 1.22–16.1 p = 0.024) from a border was identified as a risk factor for Brucella spp. For FMDV (OR 79.2, 95% CI 4.52–1388.9, p = 0.003), being situated within 30 km from a town was associated with seropositivity. Furthermore, contact with wild ruminants (OR 18.2, 95% CI 1.36–244), and the presence of sheep in the household (OR 5.20, 95% CI 1.00–26.9, p = 0.049), was associated with seropositivity for PPRV, and FMDV. No significant associations between trade or distance to the Tan-Zam highway and seroprevalence were found. We recommend that the impact of trade and proximity to borders, towns and roads should be further evaluated in larger studies, ideally incorporating aspects such as temporal trade fluctuations.
Culturing circular ssDNA viruses for the production of vaccines Inventors
Meerts, Peter; Nauwynck, Hans; Misinzo, Gerald
Culturing circular ssDNA viruses for the production of vaccines Inventors
(2007-11-27) Meerts, Peter; Nauwynck, Hans; Misinzo, Gerald
The present invention relates to the use of interferon in the in vitro cultivation of animal circular ssDNA virus such as Porcine Circovirus 2 or human TT virus in an animal cell line. Increased titres of animal circular ssDNA virus are obtained by addition of interferons or agents which ensure the production of endogenous interferons by said cell line.
Dengue virus infection and associated risk factors in Africa: a systematic review and meta-analysis
(MDPI) Mwanyika, Gaspary O.; Mboera, Leonard E. G.; Rugarabamu, Sima; Ngingo, Baraka; Sindato, Calvin; Lutwama, Julius J.; Paweska, Janusz T.; Misinzo, Gerald
Detection of peste des petits ruminants and concurrent secondary diseases in sheep and goats in Ngorongoro district, Tanzania
(Springer) Kgotlele, Tebogo; Chota, Andrew; Chubwa, Choby C.; Nyasebwa, Obed; Lyimo, Beatus A.; Torsson, Emeli; Karimuribo, Esron; Kasanga, Christopher J.; Wensman, Jonas J.; Misinzo, Gerald; Shirima, Gabriel M.; Kusiluka, Lughano
Diagnosis and genotyping of African swine fever viruses from 2015 outbreaks in Zambia
(AOSIS Publishing, 2016-04-29) Thoromo, Jonas; Simulundu, Edgar; Chambaro, Herman M; Mataa, Liywalii; Lubaba, Caesar H; Pandey, Girja S; Takada, Ayato; Misinzo, Gerald; Mweene, Aaron S
In early 2015, a highly fatal haemorrhagic disease of domestic pigs resembling African swine fever (ASF) occurred in North Western, Copperbelt, and Lusaka provinces of Zambia. Molecular diagnosis by polymerase chain reaction targeting specific amplification of p72 (B646L) gene of ASF virus (ASFV) was conducted. Fourteen out of 16 domestic pigs from the affected provinces were found to be positive for ASFV. Phylogenetic analyses based on part of the p72 and the complete p54 (E183L) genes revealed that all the ASFVs detected belonged to genotypes I and Id, respectively. Additionally, epidemiological data suggest that the same ASFV spread from Lusaka to other provinces possibly through uncontrolled and/or illegal pig movements. Although the origin of the ASFV that caused outbreaks in domestic pigs in Zambia could not be ascertained, it appears likely that the virus may have emerged from within the country or region, probably from a sylvatic cycle. It is recommended that surveillance of ASF, strict biosecurity, and quarantine measures be imposed in order to prevent further spread and emergence of new ASF outbreaks in Zambia.
Drivers, risk Factors and dynamics of African Swine Fever outbreaks, southern highlands, Tanzania
(Multidisciplinary Digital Publishing Institute) Fasina, Folorunso O.; Kissinga, Henry; Mlowe, Fredy; Mshang’a, Samora; Matogo, Benedict; Mrema, Abnery; Mhagama, Adam; Makungu, Selemani; Mtui-Malamsha, Niwael; Sallu, Raphael; Misinzo, Gerald; Magidanga, Bishop; Kivaria, Fredrick; Bebay, Charles; Nong’ona, Solomon; Kafeero, Fred; Nonga, Hezron
Drivers, risk Factors and dynamics of African Swine Fever outbreaks, southern highlands, Tanzania
(Multidisciplinary Digital Publishing Institute, 2020-02-25) Fasina, Folorunso O.; Kissinga, Henry; Mlowe, Fredy; Mshang’a, Samora; Matogo, Benedict; Mrema, Abnery; Mhagama, Adam; Makungu, Selemani; Mtui-Malamsha, Niwael; Sallu, Raphael; Misinzo, Gerald; Magidanga, Bishop; Kivaria, Fredrick; Bebay, Charles; Nong’ona, Solomon; Kafeero, Fred; Nonga, Hezron
African swine fever remains an important pig disease globally in view of its rapid spread, economic impacts and food implications, with no option of vaccination or treatment. The Southern Highlands zone of Tanzania, an important pig-producing hub in East Africa, is endemic with African swine fever (ASF). From approximately the year 2010, the recurrence of outbreaks has been observed and it has now become a predictable pattern. We conducted exploratory participatory epidemiology and participatory disease surveillance in the Southern Highlands to understand the pig sector and the drivers and facilitators of infections, risk factors and dynamics of ASF in this important pig-producing area. Pigs continue to play a major role in rural livelihoods in the Southern Highlands and pork is a major animal protein source. Outbreaks of diseases, particularly ASF, have continued to militate against the scaling up of pig operations in the Southern Highlands. Intra- and inter-district and trans-border transnational outbreaks of ASF, the most common disease in the Southern Highlands, continue to occur. Trade and marketing systems, management systems, and lack of biosecurity, as well as anthropogenic (human) issues, animals and fomites, were identified as risk factors and facilitators of ASF infection. Changes in human behavior and communication in trade and marketing systems in the value chain, biosecurity and pig management practices are warranted. Relevant training must be implemented alongside the launch of the national ASF control strategy for Tanzania, which already established a roadmap for combating ASF in Tanzania. The high-risk points (slaughter slabs, border areas, and farms with poor biosecurity) and high-risk period (November–March) along the pig value chain must be targeted as critical control points for interventions in order to reduce the burden of infection.
Epidemiological investigation into the introduction and factors for spread of Peste des Petits Ruminants, southern Tanzania:
(AOSIS) Muse, Epaphras A; Karimuribo, Esron D; Misinzo, Gerald; Mellau, Lesakit SB; Msoffe, Peter LM; Gitao, George C; Swai, Emmanuel S
Epidemiological investigation into the introduction and factors for spread of Peste des Petits Ruminants, southern Tanzania:
(AOSIS, 2012-01) Muse, Epaphras A; Karimuribo, Esron D; Misinzo, Gerald; Mellau, Lesakit SB; Msoffe, Peter LM; Gitao, George C; Swai, Emmanuel S
A study was carried out to confirm and identify sources and elucidate factors associated with the introduction of Peste des Petits Ruminants (PPR) in southern Tanzania. This study was conducted in Tandahimba and Newala districts of Mtwara region following suspected outbreak of PPR in the area. Qualitative data were collected using semi-structured questionnaires and in-depth interviews of key informants who included goat and sheep owners with suspected cases of PPR and animal health service providers as well as local administrative authority. Additionally, 216 serum samples and 28 swabs were collected for serological and virological laboratory disease confirmation. The results show that PPR was first introduced in Likuna village of Newala district in February 2009 through newly purchased goats from the Pugu livestock market located about 700 km in the outskirts of Dar es Salaam city …
Exposure to salinity and light spectra regulates glucosinolates, phenolics, and antioxidant capacity of brassica carinata L. microgreens
(MDPI, 2021-07-26) Maina, Sylvia; Ryu, Da Hye; Cho, Jwa Yeong; Jung, Da Seul; Park, Jai-Eok; Nho, Chu Won; Bakari, Gaymary; Misinzo, Gerald; Jung, Je Hyeong; Yang, Seung-Hoon; Kim, Ho-Youn
The effect of salt treatment on Brassica carinata (BC) microgreens grown under different light wavelengths on glucosinolates (GLs) and phenolic compounds were evaluated. Quantifiable GLs were identified using ultra-high performance-quadrupole time of flight mass spectrometry. Extracts’ ability to activate antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT)) was evaluated on human colorectal carcinoma cells (HCT116). Furthermore, BC compounds’ ability to activate expression of nuclear transcription factor-erythroid 2 related factor (Nrf2) and heme- oxygenase-1 (HO-1) proteins was examined using specific antibodies on HCT116 cells. Sinigrin (SIN) was the abundant GLs of the six compounds identified and its content together with total aliphatic GLs increased in saline conditions. Fluorescent (FL) and blue plus red (B1R1) lights were identified as stable cultivation conditions for microgreens, promoting biomass and glucobrassicin contents, whereas other identified individual and total indole GLs behaved differently in saline and non-saline environments. Blue light-emitting diodes and FL light in saline treatments mostly enhanced SIN, phenolics and antioxidant activities. The increased SOD and CAT activities render the BC microgreens suitable for lowering oxidative stress. Additionally, activation of Nrf2, and HO-1 protein expression by the GLs rich extracts, demonstrate their potential to treat and prevent oxidative stress and inflammatory disorders. Therefore, effective salt treatments and light exposure to BC microgreens present an opportunity for targeted regulation of growth and accumulation of bioactive metabolites.
Filter paper is a simple and cost-effective transport medium for serological diagnosis of Peste des petits ruminants
(Elsevie) Torsson, Emeli; Abubakar, Muhammad; Alvåsen, Karin; Manzoor, Shumaila; Roos, Nils; Zahur, Aamer; Misinzo, Gerald; Berg, Mikael; Wensman, Jonas
Filter paper is a simple and cost-effective transport medium for serological diagnosis of Peste des petits ruminants
(Elsevie, 2019-01) Torsson, Emeli; Abubakar, Muhammad; Alvåsen, Karin; Manzoor, Shumaila; Roos, Nils; Zahur, Aamer; Misinzo, Gerald; Berg, Mikael; Wensman, Jonas
Peste des petits ruminants (PPR) is a highly contagious disease caused by peste-des-petits-ruminants virus. Following the successful eradication of the related rinderpest virus, a program to control and eradicate PPR was launched by the FAO and OIE. PPR is today present in many tropical countries where maintaining the cold chain for sample transportation is one of the major barriers for timely processing. Transport of samples on filter paper is a simple and cost-effective method, however validation and optimization is required to fully adapt this approach. The objective of this study was to evaluate and validate the use of filter paper in serological diagnosis of PPR. Blood samples (serum and filter paper) were collected from sheep and goats in both Tanzania and Pakistan and analysed using a PPRV-specific cELISA. The positive proportion was 10.7% in Tanzania and 80% in Pakistan when performing the analysis on serum. These results were then considered as reference and compared to the results from the filter papers analysed by the same cELISA. According to the statistical analysis the cut-off for a positive results for samples stored on filter paper was adjusted from <50 % competition percentage to <84% in Tanzania and to <69% in Pakistan. These results demonstrate that filter papers are an acceptable and cost-effective transport method of whole blood samples for later use in serological analysis.
Forty-two years of responding to ebola virus outbreaks in Sub-Saharan Africa: a review
(BMJ Global Health) Rugarabamu, Sima; Mboera, Leonard; Rweyemamu, Mark; Mwanyika, Gaspary; Lutwama, Julius; Paweska, Janusz; Misinzo, Gerald