Epidemiology and impact of foot-and-mouth disease in districts located along the Uganda and Tanzania border

A Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Doctor of Philosophy in Life Sciences of the Nelson Mandela African Institution of Science and TechnologyThe Uganda-Tanzania border area lies within the main risk areas for foot-and-mouth disease (FMD) circulation. With the introduction of the progressive control pathway for FMD in eastern Africa, reliable information on FMD epidemiology along the Uganda-Tanzania border area is important in informing the pathway such that, strategic collaborative controls are designed. The scarcity of information on FMD impact in both Uganda and Tanzania, leaves a gap in information critical for justification for national and regional expenditures for FMD intervention. The objectives of the present study were to; (i) determine the spatial and temporal distribution of FMD in districts along the Uganda–Tanzania border between 2011 and 2016 (ii) determine genetic relationships between FMD viruses circulating between 2016 and 2017 and, (iii) ascertain the impact of FMD on income and food security. The study was carried out in the border districts of Missenyi and Kyerwa in Tanzania and Rakai and Isingiro in Uganda. For objective (i), retrospective data was compiled and analysed in R and maps were drawn using QGIS. Results showed that 46% of the 82 recorded outbreaks occurred in sub-counties/wards immediately neighbouring the Uganda-Tanzania border and 69.5% of the outbreaks occurred during dry months. For objective (ii), 43 samples were analysed using PCR and 11 were successfully sequenced. Sequences were analysed and trees drawn using MEGA 7. Phylogenetic analysis of the VP1 coding region showed that serotype O viruses obtained belonged to EA-2 topotype and clustered together with an average sequence divergence of 4.9%. Obtained serotype A viruses belonged to Africa-G1 topotype, formed one cluster with a 7.4% sequence divergence. For objective (iii) data was collected from 288 households using a structured questionnaire. Results showed significant reduction in income from livestock and livestock products sales by over 60%, whereas livestock market prices decreased by nearly half. Forty nine percent of farmers reported calf mortalities and milk consumption in households reduced by 57% in Rakai and Isingiro and 48% in Missenyi. These findings provide information helpful for policy reform, and designing better strategies for FMD control. The study recommends comprehensive regional studies to be implemented in border areas

Low topotype diversity of recent foot-and-mouth disease virus serotypes O and A from districts located along the Uganda and Tanzania border

Foot-and-mouth disease (FMD) is one of the most important livestock diseases in East Africa with outbreaks reported annually that cause severe economic losses. It is possible to control disease using vaccination, but antigenic matching of the vaccine to circulating strains is critical. To determine the relationship between foot-and-mouth disease viruses circulating in districts along the Uganda and Tanzanian border between 2016 and 2017 and currently used vaccines, phylogenetic analysis of the full VP1 virus sequences was carried out on samples collected from both sides of the border. A total of 43 clinical samples were collected from animals exhibiting signs of FMD and VP1 sequences generated from 11 of them. Eight out of the 11 sequences obtained belonged to serotype O and three belonged to serotype A. The serotype O sequences obtained showed limited nucleotide divergence (average of 4.9%) and belonged to topotype East Africa-2, whereas the most common O-type vaccine strain used in the region (O/KEN/77/78) belonged to East Africa-1. The serotype A viruses belonged to topotype Africa-G1 (average nucleotide divergence 7.4%), as did vaccine strain K5/1980. However, vaccine strain K35/1980 belonged to Africa G VII with an average sequence divergence of 20.5% from the study sequences. The genetic distances between current vaccine strains and circulating field strains underscores the crucial need for regular vaccine matching and the importance of collaborative efforts for better control of FMD along this border area

Comprehensive transcriptome of the maize stalk borer, Busseola fusca, from multiple tissue types, developmental stages, and parasitoid wasp exposures

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