Browsing by Author "Cleaveland, S."

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A field vaccine trial in Tanzania demonstrates partial protection against malignant catarrhal fever in cattle
(ELSEVIER) Lankester, F.; Russell, G. C.; Lugelo, A.; Ndabigaye, A.; Mnyambwa, N.; Keyyu, J.; Kazwala, R. R.; Grant, D; Percival, A.; Deane, D.; Haig, D. M.; Cleaveland, S.
A field vaccine trial in Tanzania demonstrates partial protection against malignant catarrhal fever in cattle
(Elsevier) Lankester, F; Lugelo, A; Ndabigaye, A; Mnyambwa, N; Keyyu, J.; Kazwala, R.; Grant, D; Percival, A.; Deane, D; Haig, D.M.; Cleaveland, S.; Russell, G. C.
A field vaccine trial in Tanzania demonstrates partial protection against malignant catarrhal fever in cattle
(ELSEVIER, 2015) Lankester, F.; Russell, G. C.; Lugelo, A.; Ndabigaye, A.; Mnyambwa, N.; Keyyu, J.; Kazwala, R. R.; Grant, D; Percival, A.; Deane, D.; Haig, D. M.; Cleaveland, S.
Malignant catarrhal fever (MCF) is a fatal lymphoproliferative disease of cattle that, in East Africa, results from transmission of the causative virus, alcelaphine herpesvirus 1 (AlHV-1), from wildebeest. A vaccine field trial involving an attenuated AlHV-1 virus vaccine was performed over two wildebeest calving seasons on the Simanjiro Plain of northern Tanzania. Each of the two phases of the field trial consisted of groups of 50 vaccinated and unvaccinated cattle, which were subsequently exposed to AlHV-1 challenge by herding toward wildebeest. Vaccination resulted in the induction of virus-specific and virus-neutralizing antibodies. Some cattle in the unvaccinated groups also developed virus-specific antibody responses but only after the start of the challenge phase of the trial. PCR of DNA from blood samples detected AlHV-1 infection in both groups of cattle but the frequency of infection was significantly lower in the vaccinated groups. Some infected animals showed clinical signs suggestive of MCF but few animals went on to develop fatal MCF, with similar numbers in vaccinated and unvaccinated groups. This study demonstrated a baseline level of MCF-seropositivity among cattle in northern Tanzania of 1% and showed that AlHV-1 virus-neutralizing antibodies could be induced in Tanzanian zebu shorthorn cross cattle by our attenuated vaccine, a correlate of protection in previous experimental trials. The vaccine reduced infection rates by 56% in cattle exposed to wildebeest but protection from fatal MCF could not be determined due to the low number of fatal cases.
A field vaccine trial in Tanzania demonstrates partial protection against malignant catarrhal fever in cattle
(Elsevier, 2016) Lankester, F; Lugelo, A; Ndabigaye, A; Mnyambwa, N; Keyyu, J.; Kazwala, R.; Grant, D; Percival, A.; Deane, D; Haig, D.M.; Cleaveland, S.; Russell, G. C.
Malignant catarrhal fever (MCF) is a fatal lymphoproliferative disease of cattle that, in East Africa, results from transmission of the causative virus, alcelaphine herpesvirus 1 (AlHV-1), from wildebeest. A vaccine field trial involving an attenuated AlHV-1 virus vaccine was performed over two wildebeest calving seasons on the Simanjiro Plain of northern Tanzania. Each of the two phases of the field trial consisted of groups of 50 vaccinated and unvaccinated cattle, which were subsequently exposed to AlHV-1 challenge by herding toward wildebeest. Vaccination resulted in the induction of virus-specific and virus-neutralizing antibodies. Some cattle in the unvaccinated groups also developed virus-specific antibody responses but only after the start of the challenge phase of the trial. PCR of DNA from blood samples detected AlHV-1 infection in both groups of cattle but the frequency of infection was significantly lower in the vaccinated groups. Some infected animals showed clinical signs suggestive of MCF but few animals went on to develop fatal MCF, with similar numbers in vaccinated and unvaccinated groups. This study demonstrated a baseline level of MCF-seropositivity among cattle in northern Tanzania of 1% and showed that AlHV-1 virus-neutralizing antibodies could be induced in Tanzanian zebu shorthorn cross cattle by our attenuated vaccine, a correlate of protection in previous experimental trials. The vaccine reduced infection rates by 56% in cattle exposed to wildebeest but protection from fatal MCF could not be determined due to the low number of fatal cases.
Alcelaphine herpesvirus-1 (Malignant Catarrhal Fever Virus) in wildebeest placenta: Genetic variation of ORF50 and A9.5 alleles
(PLoS ONE) Lankester, F.; Lugelo, A.; Mnyambwa, N.; Ndabigaye, A.; Keyyu, J.; Kazwala, R. R.; Grant, D. M.; Relf, V.; Haig, D. M.; Cleaveland, S.; Russell, G. C.
Comparing methods of assessing dog rabies vaccination coverage in rural and urban communities in Tanzania
(Frontiers in Veterinary Science) Sambo, M.; Johnson, P.; Hotopp, K.; Changalucha, J.; Cleaveland, S.; Kazwala, R.; Lembo, T.; Lugelo, A.; Lushasi, K.; Maziku, M.
Domestic dog demographic structure and dynamics relevant to rabies control planning in urban areas in Africa: The case of Iringa, Tanzania
(BMC Veterinary Research) Gsell, A. S.; Knobel, D. L.; Cleaveland, S.; Kazwala, R. R.; Vounatsou, P.; Zinsstag, J.
Elucidating the phylodynamics of endemic rabies virus in eastern Africa using whole-genome sequencing
(Virus Evolution) Brunker, K.; Marston, D. A.; Horton, D. L.; Cleaveland, S.; Fooks, A. R.; Kazwala, R. R.; Ngeleja, C.; Lembo, T.; Sambo, M; Mtema, Z. J.; Sikana, L.; Wilkie, G.; Biek, R.; Hampson, K.
Genetic profile of Mycobacterium tuberculosis and treatment outcomes in human pulmonary tuberculosis in Tanzania
(Tanzania Journal of Health Research) Mfinanga, S. G. M.; Warren, R. M.; Kazwala, R. R.; Kahwa, A.; Kazimoto, T.; Kimaro, G.; Mfaume, S.; Chonde, T.; Ngadaya, E.; Egwaga, S.; Streicher, E. M.; Van Pittius, G. N. C.; Morkve, O.; Cleaveland, S.
Genetic profile of Mycobacterium tuberculosis and treatment outcomes in human pulmonary tuberculosis in Tanzania
(Tanzania Journal of Health Research, 2014-04-02) Mfinanga, S. G. M.; Warren, R. M.; Kazwala, R. R.; Kahwa, A.; Kazimoto, T.; Kimaro, G.; Mfaume, S.; Chonde, T.; Ngadaya, E.; Egwaga, S.; Streicher, E. M.; Van Pittius, G. N. C.; Morkve, O.; Cleaveland, S.
Information on the different spoligotype families of Mycobacterium tuberculosis in Tanzania is limited, and where available, restricted to small geographical areas. This article describes the genetic profile of M. tuberculosis across Tanzania and suggests how spoligotype families might affect drug resistance and treatment outcomes for smear positive pulmonary tuberculosis patients in Tanzania. We conducted the study from 2006 to 2008, and the isolates were obtained from samples collected under the routine drug resistance surveillance system. The isolates were from specimens collected from 2001 to 2007, and stored at the Central and Reference Tuberculosis Laboratory. A total of 487 isolates from 23 regions in the country were spoligotyped. We were able to retrieve clinical information for 446 isolates only. Out of the 487 isolates spoligotyped, 195(40.0%) belonged to the Central Asian (CAS) family, 84 (17.5%) to the Latin American Mediterranean (LAM) family, 49 (10.1%) to the East-African Indian (EAI) family, and 33 (6.8%) to the Beijing family. Other isolates included 1 (0.2%) for H37Rv, 10 (2.1%) for Haarlem, 4 (0.8%) for S family, 58 (11.9%) for T family and 52 (10.7%) for unclassified. No spoligotype patterns were consistent with M. bovis. Regarding treatment outcomes, the cure rate was 80% with no significant variation among the spoligotype families. The overall level of MDR TB was 2.5% (3/121), with no significant difference among the spoligotype families. All Beijing strains (11.8%, 30/254) originated from the Eastern and Southern zones of the country, of which 80% were from Dar es Salaam. Isolates from the CAS and T families were reported disproportionately from the Eastern-Southern zone, and EAI and LAM families from the Northern-Lake zones but the difference was not statistically significant. Five isolates were identified as non-tuberculous Mycobacteria. In conclusion, M. tuberculosis isolates from pulmonary tuberculosis cases in Tanzania were classified mostly within the CAS, LAM, and EAI and T families, while the Beijing family comprised about 7% isolates only. Consistently good treatment outcomes were recorded across these spoligotype families. The proportion of drug resistance strains was low. The findings also suggest variation of spoligotype families with varying geographical localities within the country, and identify this area for further research to confirm this finding.
Mobile phones as surveillance tools: Implementing and evaluating a large-scale intersectoral surveillance system for rabies in Tanzania
(PLOS Medicine) Mtema, Z.; Changalucha, J.; Cleaveland, S.; Elias, M.; Ferguson, M. H.; Halliday, J. E. B.; Haydon, D.T.; Jaswant, G.; Kazwala, R. R.; Killeen, G. F.; Lembo, T; Lushasi, K.; Malishee, A. D.; Mancy, R.; Maziku, M.; Mbunda, E. M.; Mchau, G. J. M.; Murray-Smith, R.; Rysava, K.; Said, K.; Sambo, M.; Shayo, E.; Sikana, L.; Townsend, S. E.; Urassa, H.; Hampson, K.
Mobile phones as surveillance tools: Implementing and evaluating a large-scale intersectoral surveillance system for rabies in Tanzania
(PLOS Medicine, 2016-04-12) Mtema, Z.; Changalucha, J.; Cleaveland, S.; Elias, M.; Ferguson, M. H.; Halliday, J. E. B.; Haydon, D.T.; Jaswant, G.; Kazwala, R. R.; Killeen, G. F.; Lembo, T; Lushasi, K.; Malishee, A. D.; Mancy, R.; Maziku, M.; Mbunda, E. M.; Mchau, G. J. M.; Murray-Smith, R.; Rysava, K.; Said, K.; Sambo, M.; Shayo, E.; Sikana, L.; Townsend, S. E.; Urassa, H.; Hampson, K.
Surveillance is critical to manage preventative health services and control infectious diseases. Integrated surveillance involving public health, veterinary, and environmental sectors is urgently needed to effectively manage zoonoses and vector-borne diseases. However, most surveillance in low-income countries is paper-based, provides negligible timely feedback, is poorly incentivised, and results in delays, limited reporting, inaccurate data, and costly processing. • The potential of mobile technologies for improving health system surveillance has been demonstrated through small-scale pilots, but large-scale evaluations under programmatic implementation remain rare. • An intersectoral mobile-phone–based system was developed and implemented for rabies surveillance across southern Tanzania. Since 2011, the system has facilitated near realtime reporting of animal bites and human and animal vaccine use (almost 30,000 reports) by over 300 frontline health and veterinary workers across a catchment area of 150,000 km2 with >10 million inhabitants, improving data quality, timeliness, and completeness while reducing costs. • The surveillance system infrastructure is a platform that can be further developed to improve services and deliver health interventions; for example, generating automated personalized text messages (SMS) to alert patients to their vaccination schedules improved their compliance with regimens. Other interventions targeting patients and health workers can now be implemented easily. • The system has become an integrated, popular, and valuable tool across sectors, used routinely throughout southern Tanzania to evaluate the impacts of rabies control and prevention activities and to improve their management, directly informed by the experiences of frontline users. • We discuss challenges encountered during development and deployment, how we overcame these, and our recommendations for scaling up mobile-phone–based health (mHealth) interventions in low-income countries.
Mycobacterial adenitis: role of mycobacterium bovis, non-tuberculous mycobacteria, hiv infection, and risk factors in arusha, Tanzania
(East African Medical Journal) Mfinanga, S .G .M.; Morkve, O.; Kazwala, R. R.; Cleaveland, S.; Sharp, M. J.; Kunda, J.; Nilsen, R.
Mycobacterial adenitis: role of mycobacterium bovis, non-tuberculous mycobacteria, hiv infection, and risk factors in arusha, Tanzania
(East African Medical Journal, 2004-04) Mfinanga, S .G .M.; Morkve, O.; Kazwala, R. R.; Cleaveland, S.; Sharp, M. J.; Kunda, J.; Nilsen, R.
Objective: To assess risk factors and mycobacterial agents in mycobacterial adenitis. Design: Cross sectional involving comparison analysis of high-risk groups. Setting: Seven hospitals in rural and semi-rural districts of Arusha. Subjects: The study comprised of 457 patients of clinically diagnosed mycobacterial adenitis. Interventions: Biopsy materials were cultured and identification of mycobacterial isolates, and HIV infection testing were performed using standard methods. A questionnaire was used to establish information for assessing risk factors. Main outcome measures: Proportions of mycobacterial isolates, risk factors and odds ratios. Results: Of the 457 specimens, 65(14.2%) were culture positive. Isolates identified were M. bovis, 7(10.8%) M. tuberculosis, 27(41.5%) and non-tuberculous mycobacteria 31(47.7%). HIV infection and ingestion of raw milk were linked with increased risk of M. bovis infection by OR of 13.6 (95% CI, 1.7 - 109.9) and 15.28 (3.26 - 71.7), respectively. On multivariate analysis, an OR of 16.2 (1.3 - 201.3) for having M. bovis adenitis was linked to HIV infection, raw milk and houses with poor ventilation. An OR of 5.2 (1.2 - 20.6) for non-tuberculous mycobacterial adenitis was linked to history of TB in the family, HIV infection, raw milk, raw animal products and poor knowledge on transmission of tuberculosis. Conclusions: M. bovis caused one out of ten cases of culture positive mycobacterial adenitis. Non-tuberculous mycobacteria were more common than M. tuberculosis (50% and 40% of the cases, respectively). HIV infection and raw animal products are among the risk factors identified for M. bovis and non-tuberculous mycobacterial adenitis.
Mycobacterium bovis in rural Tanzania: Risk factors for infection in human and cattle populations
(Tuberculosis) Cleaveland, S.; Shawa, D. J.; Mfinangac, S. G.; Shirimad, G.; Kazwalae, R. R.; Eblate, E.; Sharp, M.
Mycobacterium bovis in rural Tanzania: Risk factors for infection in human and cattle populations
(Tuberculosis, 2006-01-13) Cleaveland, S.; Shawa, D. J.; Mfinangac, S. G.; Shirimad, G.; Kazwalae, R. R.; Eblate, E.; Sharp, M.
Although bovine tuberculosis is widespread throughout Africa, very little is known about risk factors for Mycobacterium bovis infection in either human or cattle populations. A human case–control study was conducted in northern Tanzania, comparing risk factors and prevalence of cattle interdermal test positives of cases (cervical adenitis cases from which M. bovis was isolated) with age- and sexmatched controls (selected at random from potential hospital attendees within the community). A cattle cross-sectional study was also set-up involving 27 villages selected at random in four districts, with 10,549 cattle and 622 herds tested, and questionnaire surveys conducted in 239 households. M. bovis was confirmed in seven of 65 (10.8%) human cervical adenitis cases, of which only one came from a household owning infected cattle. M. bovis in human patients was associated with families in which a confirmed diagnosis of tuberculosis had previously been made (po0:001) and with households far (4100 m) from neighbours (p ¼ 0:003). In cattle, overall prevalence of intradermal test positives was low at 0.9% (0.70–1.06%), but widespread, with 11.8% (8.44–13.17%) herds containing at least one reactor. Prevalence of intradermal test positives increased significantly with cattle age (po0:001). Herds with the following risk factors had a significantly greater prevalence of intradermal test positives: 450 cattle in the herd (p ¼ 0:024); herds housed inside at night (p ¼ 0:021) and herds in contact with wildlife (p ¼ 0:041). Furthermore, villages that experienced annual flooding had a higher prevalence of infection (p ¼ 0:043).
Prevalence of echinococcosis in dogs and wild carnivores in selected Serengeti ecosystem areas of Tanzania
(African Journal Online) Eblate, E.; Nonga, H. E.; Cleaveland, S.
Prevalence of echinococcosis in dogs and wild carnivores in selected Serengeti ecosystem areas of Tanzania
(African Journal Online, 2013-05-15) Eblate, E.; Nonga, H. E.; Cleaveland, S.
A prevalence study on echinococcosis in dogs and wild carnivores was conducted in northen Tanzania. Copro-antigen ELISA was used to screen 442 dog faecal samples from Magu, Bariadi and Ngorongoro districts, together with 88 wild carnivore samples from Serengeti National Park. Overall prevalence of E. granulosus in dogs was 12.4%. Magu (14.6%) and Ngorongoro districts (10.0%) had higher prevalence than Bariadi district (6.3%). The prevalence of echinococcosis in wild carnivores was 13.6%. Species which were positive to Copro-antigen ELISA test included bat eared fox (Otocyon megalotis) (14.3%), cheetah (Acinonyx jubatus) (16.1%), spotted hyaena (Crocuta crocuta) (37.5%) and lion (Panthera leo) (10.0%). The findings uncover that dogs and wild carnivores from northern Tanzania are infected with E. granulosus, a situation which may pose a risk of infection to other hosts including human. Therefore, more epidermiological investigation is needed to understand the dynamics of the disease in human, domestic animals and wildlife.
Progress towards rabies elimination from Pemba Island, Southern Tanzania.
(Online Journal of Public Health Informatics .) Lushasi, K. S.; Cleaveland, S.; Changalucha, J. J.; Haydon, D.; Kazwala, R.; Lembo, T.; Masoud, M.; Maziku, M.; Mchau, G.; Mtema, Z.; Omar, K.; Maganga, S.; Rysava, K.; Hampson, K.
Progress towards rabies elimination from Pemba Island, Southern Tanzania.
(Online Journal of Public Health Informatics ., 2017) Lushasi, K. S.; Cleaveland, S.; Changalucha, J. J.; Haydon, D.; Kazwala, R.; Lembo, T.; Masoud, M.; Maziku, M.; Mchau, G.; Mtema, Z.; Omar, K.; Maganga, S.; Rysava, K.; Hampson, K.
Using active surveillance approaches to investigate the transmission dynamics of rabies on Pemba Island and across Southern Tanzania, whilst a large-scale dog vaccination program was underway1 , to gain a greater understanding of the dynamics of infection as the disease is driven towards elimination