The epidemiology of foot-and-mouth disease at the wildlife-livestock interface in northern Tanzania

Foot-and-mouth disease (FMD), a disease of cloven hooved animals caused by FMD virus (FMDV), is one of the most economically devastating diseases of livestock worldwide. The global burden of disease is borne largely by livestock-keepers in areas of Africa and Asia where the disease is endemic and where many people rely on livestock for their livelihoods and food-security. Yet, there are many gaps in our knowledge of the drivers of FMDV circulation in these settings. In East Africa, FMD epidemiology is complicated by the circulation of multiple FMDV serotypes (distinct antigenic variants) and by the presence of large populations of susceptible wildlife and domestic livestock. The African buffalo (Syncerus caffer) is the only wildlife species with consistent evidence of high levels of FMDV infection, and East Africa contains the largest population of this species globally. To inform FMD control in this region, key questions relate to heterogeneities in FMD prevalence and impacts in different livestock management systems and to the role of wildlife as a potential source of FMDV for livestock. To develop FMD control strategies and make best use of vaccine control options, serotype-specific patterns of circulation need to be characterised. In this study, the impacts and epidemiology of FMD were investigated across a range of traditional livestock-keeping systems in northern Tanzania, including pastoralist, agro-pastoralist and rural smallholder systems. Data were generated through field studies and laboratory analyses between 2010 and 2015. The study involved analysis of existing household survey data and generated serological data from cross-sectional livestock and buffalo samples and longitudinal cattle samples. Serological analyses included non-structural protein ELISAs, serotype-specific solid-phase competitive ELISAs, with optimisation to detect East African FMDV variants, and virus neutralisation testing. Risk factors for FMDV infection and outbreaks were investigated through analysis of cross-sectional serological data in conjunction with a case-control outbreak analysis. A novel Bayesian modeling approach was developed to infer serotype-specific infection history from serological data, and combined with virus isolation data from FMD outbreaks to characterise temporal and spatial patterns of serotype-specific infection. A high seroprevalence of FMD was detected in both northern Tanzanian livestock (69%, [66.5 - 71.4%] in cattle and 48.5%, [45.7-51.3%] in small ruminants) and in buffalo (80.9%, [74.7-86.1%]). Four different serotypes of FMDV (A, O, SAT1 and SAT2) were isolated from livestock. Up to three outbreaks per year were reported by households and active surveillance highlighted up to four serial outbreaks in the same herds within three years. Agro-pastoral and pastoral livestock keepers reported more frequent FMD outbreaks compared to smallholders. Households in all three management systems reported that FMD outbreaks caused significant impacts on milk production and sales, and on animals’ draught power, hence on crop production, with implications for food security and livelihoods. Risk factor analyses showed that older livestock were more likely to be seropositive for FMD (Odds Ratio [OR] 1.4 [1.4-1.5] per extra year) and that cattle (OR 3.3 [2.7-4.0]) were more likely than sheep and goats to be seropositive. Livestock managed by agro-pastoralists (OR 8.1 [2.8-23.6]) or pastoralists (OR 7.1 [2.9-17.6]) were more likely to be seropositive compared to those managed by smallholders. Larger herds (OR: 1.02 [1.01-1.03] per extra bovine) and those that recently acquired new livestock (OR: 5.57 [1.01 – 30.91]) had increased odds of suffering an FMD outbreak. Measures of potential contact with buffalo or with other FMD susceptible wildlife did not increase the likelihood of FMD in livestock in either the cross-sectional serological analysis or case-control outbreak analysis. The Bayesian model was validated to correctly infer from ELISA data the most recent serotype to infect cattle. Consistent with the lack of risk factors related to wildlife contact, temporal and spatial patterns of exposure to specific FMDV serotypes were not tightly linked in cattle and buffalo. In cattle, four serial waves of different FMDV serotypes that swept through southern Kenyan and northern Tanzanian livestock populations over a four-year period dominated infection patterns. In contrast, only two serotypes (SAT1 and SAT2) dominated in buffalo populations. Key conclusions are that FMD has a substantial impact in traditional livestock systems in East Africa. Wildlife does not currently appear to act as an important source of FMDV for East African livestock, and control efforts in the region should initially focus on livestock management and vaccination strategies. A novel modeling approach greatly facilitated the interpretation of serological data and may be a potent epidemiological tool in the African setting. There was a clear temporal pattern of FMDV antigenic dominance across northern Tanzania and southern Kenya. Longer-term research to investigate whether serotype-specific FMDV sweeps are truly predictable, and to shed light on FMD post-infection immunity in animals exposed to serial FMD infections is warranted.

Assessing the impacts of community participation policy and practice in Scotland and England

Background: Community participation has become an integral part of many areas of public policy over the last two decades. For a variety of reasons, ranging from concerns about social cohesion and unrest to perceived failings in public services, governments in the UK and elsewhere have turned to communities as both a site of intervention and a potential solution. In contemporary policy, the shift to community is exemplified by the UK Government’s Big Society/Localism agenda and the Scottish Government’s emphasis on Community Empowerment. Through such policies, communities have been increasingly encouraged to help themselves in various ways, to work with public agencies in reshaping services, and to become more engaged in the democratic process. These developments have led some theorists to argue that responsibilities are being shifted from the state onto communities, representing a new form of 'government through community' (Rose, 1996; Imrie and Raco, 2003). Despite this policy development, there is surprisingly little evidence which demonstrates the outcomes of the different forms of community participation. This study attempts to address this gap in two ways. Firstly, it explores the ways in which community participation policy in Scotland and England are playing out in practice. And secondly, it assesses the outcomes of different forms of community participation taking place within these broad policy contexts. Methodology: The study employs an innovative combination of the two main theory-based evaluation methodologies, Theories of Change (ToC) and Realist Evaluation (RE), building on ideas generated by earlier applications of each approach (Blamey and Mackenzie, 2007). ToC methodology is used to analyse the national policy frameworks and the general approach of community organisations in six case studies, three in Scotland and three in England. The local evidence from the community organisations’ theories of change is then used to analyse and critique the assumptions which underlie the Localism and Community Empowerment policies. Alongside this, across the six case studies, a RE approach is utilised to examine the specific mechanisms which operate to deliver outcomes from community participation processes, and to explore the contextual factors which influence their operation. Given the innovative methodological approach, the study also engages in some focused reflection on the practicality and usefulness of combining ToC and RE approaches. Findings: The case studies provide significant evidence of the outcomes that community organisations can deliver through directly providing services or facilities, and through influencing public services. Important contextual factors in both countries include particular strengths within communities and positive relationships with at least part of the local state, although this often exists in parallel with elements of conflict. Notably this evidence suggests that the idea of responsibilisation needs to be examined in a more nuanced fashion, incorporating issues of risk and power, as well the active agency of communities and the local state. Thus communities may sometimes willingly take on responsibility in return for power, although this may also engender significant risk, with the balance between these three elements being significantly mediated by local government. The evidence also highlights the impacts of austerity on community participation, with cuts to local government budgets in particular increasing the degree of risk and responsibility for communities and reducing opportunities for power. Furthermore, the case studies demonstrate the importance of inequalities within and between communities, operating through a socio-economic gradient in community capacity. This has the potential to make community participation policy regressive as more affluent communities are more able to take advantage of additional powers and local authorities have less resource to support the capacity of more disadvantaged communities. For Localism in particular, the findings suggest that some of the ‘new community rights’ may provide opportunities for communities to gain power and generate positive social outcomes. However, the English case studies also highlight the substantial risks involved and the extent to which such opportunities are being undermined by austerity. The case studies suggest that cuts to local government budgets have the potential to undermine some aspects of Localism almost entirely, and that the very limited interest in inequalities means that Localism may be both ‘empowering the powerful’ (Hastings and Matthews, 2014) and further disempowering the powerless. For Community Empowerment, the study demonstrates the ways in which community organisations can gain power and deliver positive social outcomes within the broad policy framework. However, whilst Community Empowerment is ostensibly less regressive, there are still significant challenges to be addressed. In particular, the case studies highlight significant constraints on the notion that communities can ‘choose their own level of empowerment’, and the assumption of partnership working between communities and the local state needs to take into account the evidence of very mixed relationships in practice. Most importantly, whilst austerity has had more limited impacts on local government in Scotland so far, the projected cuts in this area may leave Community Empowerment vulnerable to the dangers of regressive impact highlighted for Localism. Methodologically, the study shows that ToC and RE can be practically applied together and that there may be significant benefits of the combination. ToC offers a productive framework for policy analysis and combining this with data derived from local ToCs provides a powerful lens through which to examine and critique the aims and assumptions of national policy. ToC models also provide a useful framework within which to identify specific causal mechanisms, using RE methodology and, again, the data from local ToC work can enable significant learning about ‘what works for whom in what circumstances’ (Pawson and Tilley, 1997).