Northeast South Africa Research Articles

Decentralization, healthcare access, and inequality in Mpumalanga, South Africa

Healthcare access and utilization remain key challenges in the Global South. South Africa represents this given that more than twenty years after the advent of democratic elections, the national government continues to confront historical systems of spatial manipulation that generated inequities in healthcare access. While the country has made significant advancements, governmental agencies have mirrored international strategies of healthcare decentralization and focused on local provision of primary care to increase healthcare access. In this paper, we show the significance of place in shaping access and health experiences for rural populations. Using data from a structured household survey, focus group discussions, qualitative interviews, and clinic data conducted in northeast South Africa from 2013 to 2016, we argue that decentralization fails to resolve the uneven landscapes of healthcare in the contemporary period. This is evidenced by the continued variability across the study area in terms of government-sponsored healthcare, and constraints in the clinics in terms of staffing, privacy, and patient loads, all of which challenge the access-related assumptions of healthcare decentralization.

HIV as social and ecological experience

The spread and varied impacts of the HIV/AIDS epidemic demonstrate the complex and reciprocal relationships between the socio-political and biophysical dimensions of human health. Yet even with increasing research and policy attention there remain critical gaps in the literature on how HIV-positive households manage health through their engagement with social and ecological systems. This is particularly urgent given improvements in the global response to the epidemic, whereby expanded access to antiretroviral therapy has extended the possibility for survival for years or decades. Because many HIV-positive families and communities in the Global South remain dependent upon a diverse set of resources to generate income and meet subsistence needs, the impacts of disease must be understood within a mix of social processes, including the maintenance of land and collection of natural resources. Similarly, biophysical systems disrupted by HIV/AIDS vary depending upon resource use and locally-specific dynamics that influence opportunities for agrarian production. This paper reports on the findings from a structured survey completed in three communities in northeast South Africa in 2013 that is integrated with focus group discussions and qualitative interviews conducted from 2012–2016. We concentrate upon the diverse ways that individuals and families experience HIV through livelihood systems that are reliant on economic and natural resources. Because the access and use of these resources are mediated by existing social, cultural, and institutional systems, as well as historical spatial economies, we analyze how this produces differential lived experiences for HIV-positive individuals and households in the age of expanded access to antiretroviral therapy.

A geomorphological characterisation of river systems in South Africa: A case study of the Sabie River

Fluvial geomorphology affects river character, behaviour, evolution, trajectory of change and recovery potential, and as such affects biophysical interactions within a catchment. Water bodies in South Africa, in common with many other water-stressed parts of the world, are generally under threat due to increasing natural and anthropogenic influences including aridity, siltation and pollution, as well as climate and environmental change. This study reports on a case study to characterise the geomorphology of different river systems in South Africa, with the aim of better understanding their properties, controls, and implications for biophysical interactions including water quality, biodiversity (aquatic and riparian), and human activity within the catchment. The approach adopted is based on the River Styles® framework (RSF), a geomorphology-based approach developed for rivers in New Zealand and Australia, but applied here for the first time to South Africa. Based on analysis of remote sensing imagery, SRTM-2 digital topographic data and field observations on sites through the entire river system, six geomorphic elements were identified along the Sabie River, northeast South Africa (gorge, bedrock-forced meander, low-moderate sinuosity planform controlled sand bed, meandering sand bed, low sinuosity fine grained sand bed, and floodouts), using the RSF classification scheme and based on the RSF procedural tree of Brierley and Fryirs (2005). Previous geomorphological studies along the Sabie River have shown that different reaches respond differently to episodic floods; we use these data to link river geomorphological character (as defined by the RSF) to the hydrodynamic conditions and processes giving rise to such character. This RSF approach can be used to develop a new management approach for river systems that considers their functional biophysical behaviour within individual reaches, rather than considering them as homogeneous and uniform systems.

Disparities in Management of Cardiovascular Disease in Rural South Africa: Data From the HAALSI Study (Health and Aging in Africa: Longitudinal Studies of International Network for the Demographic Evaluation of Populations and Their Health Communities).

Optimal secondary prevention is critical for the reduction of repeated cardiovascular events, and the control of cardiovascular risk factors in this context is essential. Data on secondary prevention of cardiovascular disease (CVD) in sub-Saharan Africa are needed to inform intervention strategies with a particular focus on local disparities. The aim of this study was to assess CVD management in a rural community in northeast South Africa. We recruited adults aged ≥40 years residing in the Agincourt subdistrict of Mpumalanga province. Data collection included socioeconomic and clinical data, anthropometric measures, blood pressure, human immunodeficiency virus status, and point-of-care glucose and lipid levels. CVD was defined as self-report of myocardial infarction and stroke or angina diagnosed by Rose Criteria. A linear regression model was built to identify variables independently associated with the number of cardiovascular risk factors controlled. Of 5059 subjects, 592 (11.7%) met CVD diagnostic criteria. Angina was reported in 77.0% of these subjects, stroke in 25.2%, and myocardial infarction in 3.7%. Percent controlled of the 5 individual risk factors assessed were as follows: tobacco 92.9%; blood pressure 51.2%; body mass index 33.8%; low-density lipoprotein 31.4%; and waist-to-hip ratio 29.7%. Only 4.4% had all 5 risk factors controlled and 42.4% had ≥3 risk factors controlled. Male sex (β coefficient=0.44; 95% confidence interval, 0.25-0.63; P<0.001), absence of physical disability (β coefficient=0.40; 95% confidence interval, 0.16-0.65; P=0.001), and socioeconomic status (β coefficient=0.10; 95% confidence interval, 0.01-0.19; P=0.035) were directly associated with the number of risk factors controlled. Currently, CVD is not being optimally managed in this rural area of South Africa. There are significant disparities in control of CVD risk factors by sex, socioeconomic status, and level of disability. Efforts to improve secondary prevention in this population should be focused on females, subjects from lower socioeconomic status, and those with physical disabilities.

Initiating a participatory action research process in the Agincourt health and socio-demographic surveillance site.

BackgroundDespite progressive health policy, disease burdens in South Africa remain patterned by deeply entrenched social inequalities. Accounting for the relationships between context, health and risk can provide important information for equitable service delivery. The aims of the research were to initiate a participatory research process with communities in a low income setting and produce evidence of practical relevance.MethodsWe initiated a participatory action research (PAR) process in the Agincourt health and socio–demographic surveillance site (HDSS) in rural north–east South Africa. Three village–based discussion groups were convened and consulted about conditions to examine, one of which was under–5 mortality. A series of discussions followed in which routine HDSS data were presented and participants’ subjective perspectives were elicited and systematized into collective forms of knowledge using ranking, diagramming and participatory photography. The process concluded with a priority setting exercise. Visual and narrative data were thematically analyzed to complement the participants’ analysis.ResultsA range of social and structural root causes of under–5 mortality were identified: poverty, unemployment, inadequate housing, unsafe environments and shortages of clean water. Despite these constraints, single mothers were often viewed as negligent. A series of mid–level contributory factors in clinics were also identified: overcrowding, poor staffing, delays in treatment and shortages of medications. In a similar sense, pronounced blame and negativity were directed toward clinic nurses in spite of the systems constraints identified. Actions to address these issues were prioritized as: expanding clinics, improving accountability and responsiveness of health workers, improving employment, providing clean water, and expanding community engagement for health promotion.ConclusionsWe initiated a PAR process to gain local knowledge and prioritize actions. The process was acceptable to those involved, and there was willingness and commitment to continue. The study provided a basis from which to gain support to develop fuller forms of participatory research in this setting. The next steps are to build deeper involvement of participants in the process, expand to include the perspectives of those most marginalized, and engage in the health system at different levels to move toward an ongoing process of action and learning from action.

Using record linkage to assess the impact of late presentation for care and treatment on short-term mortality among HIV-infected adults in rural South Africa.

ABSTRACT&#x0D; ObjectivesTo assess the impact of late presentation (CD4 cell count &lt;200 cells/μl at presentation) for care and treatment on short-term mortality (death within a year of presentation) among HIV-infected adults in rural South Africa.&#x0D; ApproachWe applied deterministic and probabilistic record linkage approaches to link adult patients seeking care and treatment for HIV from a health facility between 2007 and 2013 to population under continuous surveillance by the Agincourt Health and Demographic Surveillance System (HDSS) in rural northeast South Africa. The resulting record-linked dataset was thereafter analysed to estimate short-term mortality (death within a year of presentation) differences in late presenters (initial presentation at health facility with CD4 cell count less than 200 cells/μl) and early presenters (presentation with CD4 cell count of 200 or more cells/μl). In the linked dataset, CD4 cell count was extracted from the health facility database where as date of death came from the HDSS database.&#x0D; ResultsA total of 3,553 patients who sought care and treatment for HIV at Bhubhezi clinic between 2007 and 2013 were linked to the Agincourt HDSS surveillance population. Proportion of patients classified as late presenters was 60.9%. Short-term mortality was 8.9% (317/3,553): 11.1% among those who presented late and 5.5 % among those who presented early (P&lt;0.001).&#x0D; ConclusionRecord linkage facilitated the assessment of the impact of late presentation for care and treatment on short-term mortality among HIV-infected adults in rural South Africa. In the population studied, late presentation is high and is contributing to high mortality among people living with HIV. Strategies that would facilitate early presentation are needed in order to reduce mortality among people living with HIV.

Relationships between structure, process and outcome to assess quality of integrated chronic disease management in a rural South African setting: applying a structural equation model

BackgroundSouth Africa faces a complex dual burden of chronic communicable and non-communicable diseases (NCDs). In response, the Integrated Chronic Disease Management (ICDM) model was initiated in primary health care (PHC) facilities in 2011 to leverage the HIV/ART programme to scale-up services for NCDs, achieve optimal patient health outcomes and improve the quality of medical care. However, little is known about the quality of care in the ICDM model. The objectives of this study were to: i) assess patients’ and operational managers’ satisfaction with the dimensions of ICDM services; and ii) evaluate the quality of care in the ICDM model using Avedis Donabedian’s theory of relationships between structure (resources), process (clinical activities) and outcome (desired result of healthcare) constructs as a measure of quality of care.MethodsA cross-sectional study was conducted in 2013 in seven PHC facilities in the Bushbuckridge municipality of Mpumalanga Province, north-east South Africa - an area underpinned by a robust Health and Demographic Surveillance System (HDSS). The patient satisfaction questionnaire (PSQ-18), with measures reflecting structure/process/outcome (SPO) constructs, was adapted and administered to 435 chronic disease patients and the operational managers of all seven PHC facilities. The adapted questionnaire contained 17 dimensions of care, including eight dimensions identified as priority areas in the ICDM model - critical drugs, equipment, referral, defaulter tracing, prepacking of medicines, clinic appointments, waiting time, and coherence. A structural equation model was fit to operationalise Donabedian’s theory, using unidirectional, mediation, and reciprocal pathways.ResultsThe mediation pathway showed that the relationships between structure, process and outcome represented quality systems in the ICDM model. Structure correlated with process (0.40) and outcome (0.75). Given structure, process correlated with outcome (0.88). Of the 17 dimensions of care in the ICDM model, three structure (equipment, critical drugs, accessibility), three process (professionalism, friendliness and attendance to patients) and three outcome (competence, confidence and coherence) dimensions reflected their intended constructs.ConclusionOf the priority dimensions, referrals, defaulter tracing, prepacking of medicines, appointments, and patient waiting time did not reflect their intended constructs. Donabedian’s theoretical framework can be used to provide evidence of quality systems in the ICDM model.

Gender Norms, Gender Role Conflict/Stress and HIV Risk Behaviors Among Men in Mpumalanga, South Africa.

Men's gender role conflict and stress (GRC/S), the psychological strain they experience around fulfilling expectations of themselves as men, has been largely unexplored in HIV prevention research. We examined associations between both men's gender norms and GRC/S and three HIV risk behaviors using data from a population-based survey of 579 18-35year-old men in rural northeast South Africa. Prevalence of sexual partner concurrency and intimate partner violence (IPV) perpetration in the last 12months were 38.0 and 13.4%, respectively; 19.9% abused alcohol. More inequitable gender norms and higher GRC/S were each significantly associated with an increased odds of concurrency (p=0.01; p<0.01, respectively), IPV perpetration (p=0.03; p<0.01), and alcohol abuse (p=0.02; p<0.001), controlling for demographic characteristics. Ancillary analyses demonstrated significant positive associations between: concurrency and the GRC/S sub-dimension subordination to women; IPV perpetration and restrictive emotionality; and alcohol abuse and success, power, competition. Programs to transform gender norms should be coupled with effective strategies to prevent and reduce men's GRC/S.

Quality of integrated chronic disease care in rural South Africa: user and provider perspectives.

The integrated chronic disease management (ICDM) model was introduced as a response to the dual burden of HIV/AIDS and non-communicable diseases (NCDs) in South Africa, one of the first of such efforts by an African Ministry of Health. The aim of the ICDM model is to leverage HIV programme innovations to improve the quality of chronic disease care. There is a dearth of literature on the perspectives of healthcare providers and users on the quality of care in the novel ICDM model. This paper describes the viewpoints of operational managers and patients regarding quality of care in the ICDM model.In 2013, we conducted a case study of the seven PHC facilities in the rural Agincourt sub-district in northeast South Africa. Focus group discussions (n = 8) were used to obtain data from 56 purposively selected patients ≥18 years. In-depth interviews were conducted with operational managers of each facility and the sub-district health manager. Donabedian’s structure, process and outcome theory for service quality evaluation underpinned the conceptual framework in this study. Qualitative data were analysed, with MAXQDA 2 software, to identify 17 a priori dimensions of care and unanticipated themes that emerged during the analysis.The manager and patient narratives showed the inadequacies in structure (malfunctioning blood pressure machines and staff shortage); process (irregular prepacking of drugs); and outcome (long waiting times). There was discordance between managers and patients regarding reasons for long patient waiting time which managers attributed to staff shortage and missed appointments, while patients ascribed it to late arrival of managers to the clinics. Patients reported anti-hypertension drug stock-outs (structure); sub-optimal defaulter-tracing (process); rigid clinic appointment system (process). Emerging themes showed that patients reported HIV stigmatisation in the community due to defaulter-tracing activities of home-based carers, while managers reported treatment of chronic diseases by traditional healers and reduced facility-related HIV stigma because HIV and NCD patients attended the same clinic.Leveraging elements of HIV programmes for NCDs, specifically hypertension management, is yet to be achieved in the study setting in part because of malfunctioning blood pressure machines and anti-hypertension drug stock-outs. This has implications for the nationwide scale up of the ICDM model in South Africa and planning of an integrated chronic disease care in other low- and middle-income countries.

The organization of salt production in early first millennium CE South Africa

Salt production is an industry directly associated with the spread and emergence of agricultural communities of southern Africa’s Early Iron Age. It is also one of the few economic activities from the period prior to 650 CE for which direct in situ production evidence exists. Research conducted at the Baleni salt production site in northeast South Africa focused on activities by communities associated with Mzonjani ceramics (c. 350–650 CE). Analysis of the context, concentration and intensity of production provide an understanding of how these communities accessed resources and mobilized labor. These parameters suggest that production was probably done by multiple small groups on a seasonal basis. Output was likely for own consumption rather than explicitly focused on trade. This research emphasizes the value of approaching resource extraction in non-state societies through distinct organizational principles often reserved for analysis of craft production in complex societies.

Measuring Men's Gender Norms and Gender Role Conflict/Stress in a High HIV-Prevalence South African Setting.

Gender norms and gender role conflict/stress may influence HIV risk behaviors among men; however scales measuring these constructs need further development and evaluation in African settings. We conducted exploratory and confirmatory factor analyses to evaluate the Gender Equitable Men's Scale (GEMS) and the Gender Role Conflict/Stress (GRC/S) scale among 581 men in rural northeast South Africa. The final 17-item GEMS was unidimensional, with adequate model fit and reliability (alpha=0.79). Factor loadings were low (0.2-0.3) for items related to violence and sexual relationships. The final 24-item GRC/S scale was multidimensional with four factors: Success, power, competition; Subordination to women; Restrictive emotionality; and Sexual prowess. The scale had adequate model fit and good reliability (alpha=0.83). While GEMS is a good measure of inequitable gender norms, new or revised scale items may need to be explored in the South African context. Adding the GRC/S scale to capture men's strain related to gender roles could provide important insights into men's risk behaviors.

Erythristic leopards &lt;i&gt;Panthera pardus&lt;/i&gt; in South Africa

Background: Leopards (Panthera pardus) show genetically determined colour variation. Erythristic (strawberry) morphs, where individuals are paler and black pigment in the coat is replaced by a red-brown colour, are exceptionally rare in the wild. Historically, few records exist, with only five putative records known from India.Objectives: To record the presence of erythristic leopards in our study site (Thaba Tholo Wilderness Reserve, Mpumalanga) and to collate records from across South Africa. Method: A network of camera traps was used to record individual leopards at Thaba Tholo. We also surveyed local experts, searched the popular South African press, and used social media to request observations.Results: Two out of 28 individual leopards (7.1%) recorded in our study site over 3 years were of this colour morph. We obtained records of five other erythristic leopards in the North West and Mpumalanga regions, with no reports outside of this population.Conclusions: Erythristic leopards are widely dispersed across north-east South Africa, predominantly in the Lydenburg region, Mpumalanga. The presence of this rare colour morph may reflect the consequences of population fragmentation.

Social patterns and differentials in the fertility transition in the context of HIV/AIDS: evidence from population surveillance, rural South Africa, 1993 - 2013.

BackgroundLiterature is limited on the effects of high prevalence HIV on fertility in the absence of treatment, and the effects of the introduction of sustained access to antiretroviral therapy (ART) on fertility. We summarize fertility patterns in rural northeast South Africa over 21 years during dynamic social and epidemiological change.MethodsWe use data for females aged 15–49 from the Agincourt health and socio-demographic surveillance system (1993–2013). We use discrete time event history analysis to summarize patterns in the probability of any birth.ResultsOverall fertility declined in 2001–2003, increased in 2004–2011, and then declined in 2012–2013. South Africans showed a similar pattern. Mozambicans showed a different pattern, with strong declines prior to 2003 before stalling during 2004–2007, and then continued fertility decline afterwards. There was an inverse gradient between fertility levels and household socioeconomic status. The gradient did not vary by time or nationality.ConclusionsThe fertility transition in rural South Africa shows a pattern of decline until the height of the HIV/AIDS pandemic, with a resulting stall until further decline in the context of ART rollout. Fertility patterns are not homogenous among groups.

Community perspectives on HIV, violence and health surveillance in rural South Africa: a participatory pilot study

BackgroundSouth Africa faces a complex burden of disease consisting of infectious and non–communicable conditions, injury and interpersonal violence, and maternal and child mortality. Inequalities in income and opportunity push disease burdens towards vulnerable populations, a situation to which the health system struggles to respond. There is an urgent need for health planning to account for the needs of marginalized groups in this context. The study objectives were to develop a process to elicit the perspectives of local communities in the established Agincourt health and socio-demographic surveillance site (HDSS) in rural north–east South Africa on two leading causes of death: HIV/AIDS and violent assault, and on health surveillance as a means to generate information on health in the locality.MethodsDrawing on community–based participatory research (CBPR) methods, three village–based groups of eight participants were convened, with whom a series of discussions were held to identify and define the causes of, treatments for, and problems surrounding, deaths due to HIV/AIDS and violent assault. The surveillance system was also discussed and recommendations generated. The discussion narratives were the main data source, examined using framework analysis.ResultsThe groups identified a range of social and health systems issues including risky sexual health behaviors, entrenched traditional practices, alcohol and substance abuse, unstable relationships, and debt as causative. Participants also explained how compromised patient confidentiality in clinics, insensitive staff, and a biased judicial system were problematic for the treatment and reporting of both conditions. Views on health surveillance were positive. Recommendations to strengthen an already well–functioning system related to maintaining confidentiality and sensitivity, and extending ancillary care obligations.ConclusionThe discussions provided information not available from other sources on the social and health systems processes through which access to good quality health care is constrained in this setting. On this basis, further CBPR in routine HDSS to extend partnerships between researchers, communities and health authorities to connect evidence with the means for action is underway.

Involvement of stakeholders in determining health priorities of adolescents in rural South Africa

BackgroundWhen developing intervention research, it is important to explore issues from the community perspective. Interventions that promote adolescent health in South Africa are urgently needed, and Project Ntshembo (‘hope’) aims to improve the health of young women and their offspring in the Agincourt sub-district of rural northeast South Africa, actively using stakeholder involvement throughout the research process.ObjectiveThis study aimed to determine adolescent health priorities according to key stakeholders, to align stakeholder and researcher priorities, and to form a stakeholder forum, which would be active throughout the intervention.DesignThirty-two stakeholders were purposefully identified as community members interested in the health of adolescents. An adapted Delphi incorporating face-to-face discussions, as well as participatory visualisation, was used in a series of three workshops. Consensus was determined through non-parametric analysis.ResultsStakeholders and researchers agreed that peer pressure and lack of information, or having information but not acting on it, were the root causes of adolescent health problems. Pregnancy, HIV, school dropout, alcohol and drug abuse, not accessing health services, and unhealthy lifestyle (leading to obesity) were identified as priority adolescent health issues. A diagram was developed showing how these eight priorities relate to one another, which was useful in the development of the intervention. A stakeholder forum was founded, comprising 12 of the stakeholders involved in the stakeholder involvement process.ConclusionsThe process brought researchers and stakeholders to consensus on the most important health issues facing adolescents, and a stakeholder forum was developed within which to address the issues. Stakeholder involvement as part of a research engagement strategy can be of mutual benefit to the researchers and the community in which the research is taking place.

Governance and regulation of the tourism industry: An internet marketing perspective

The purpose of this qualitative study is to establish governance and regulation issues pertaining to Internet marketing approaches within the South African tourism sector. The study focuses on the norms and practices of Internet marketing among small-scale lodging establishments in Bushbuckridge – a small tourist town in northeast South Africa. In-depth interviews were collected from eight participating bed and breakfast (B&amp;B) owners. Findings revealed that, while Internet awareness was quite high, only a few B&amp;Bs utilised the Internet for marketing. Participants cited lack of clear industry guidelines on Internet marketing approaches as well as limited Internet experience, among others, as barriers to adoption. Implications and recommendations of the study are presented within the ambit of the existing literature.

Late Holocene Stalagmite and Tufa Climate Records for Wonderwerk Cave: Relationships Between Archaeology and Climate in Southern Africa

Horizontal cores from a large stalagmite and two tufa deposits in the entrance to Wonderwerk Cave, South Africa, dated by radiocarbon methods, have provided climate proxy data on late Holocene environments near the cave. The δ18O and δ13C time series from stalagmite Core WW1–3 and tufa Core WW3 correlate well with isotope records for other sites in the summer rainfall zone of southern Africa and suggest that late Holocene warm periods in the Northern Hemisphere, including the Medieval Warm period, Roman Warm period, and Minoan Warm period, were times of increased moisture in this rainfall zone. In contrast, late Holocene cold intervals in the Northern Hemisphere, including the Dark Ages Cold period and Sub-Atlantic Cold period, were times of drier climate in the summer rainfall zone. Comparison of the Wonderwerk records with information on human settlement patterns, agricultural expansion or decline, and population growth or decline, shows that growth occurred preferentially during wetter climate periods and declines, including the abandonment of the important town of Mupungubwe in the Shashe-Limpopo area of northeast South Africa and the fall of Great Zimbabwe, which occurred during periods of low precipitation.

DNA sequencing resolves species of Spongites (Corallinales, Rhodophyta) in the Northeast Pacific and South Africa, including S. agulhensis sp. nov.

:DNA sequence data from a 296 base pair variable region of the plastid encoded rbcL gene was obtained from 19th century type material of Spongites decipiens and of Lithophyllum tumidum (=Pseudolithophyllum neofarlowii) and matched to field-collected material, confirming the application of these specific epithets in the northeast Pacific. Phylogenetic analyses of separate and concatenated rbcL and psbA gene sequences show that both species belong in Spongites. Based on DNA sequences, the distribution of S. decipiens is confirmed from Haida Gwaii, British Columbia, Canada, south to its type locality at San Pedro, Los Angeles County, California, whereas, Spongites tumidum is distributed from near Sitka, Alaska, to Monterey County, California. Sequence data from S. decipiens and South African specimens called Spongites yendoi confirm anatomical studies that these two species are distinct but that a previously undescribed, cryptic species, Spongites agulhensis, also is present in South Africa. Anatomically and morphologically S. agulhensis is very similar to both northeast Pacific S. decipiens and South African S. yendoi, differing from the former by a single anatomical character and from the latter by two anatomical characters. Anatomy, ecology and distributions are useful in separating the South African species of Spongites, as well as the northeast Pacific species. Sequence divergence values align with biogeographic patterns and not with anatomical similarities for these Spongites species. We question the practice of placing into synonymy geographically widely separated non-geniculate coralline algal species based solely on anatomical features that likely have resulted from convergent evolution.

Epidemiologic and Environmental Risk Factors of Rift Valley Fever in Southern Africa from 2008 to 2011.

Background: Rift Valley fever (RVF) outbreaks have been associated with periods of widespread and above-normal rainfall over several months. Knowledge on the environmental factors influencing disease transmission dynamics has provided the basis for developing models to predict RVF outbreaks in Africa. From 2008 to 2011, South Africa experienced the worst wave of RVF outbreaks in almost 40 years. We investigated rainfall-associated environmental factors in southern Africa preceding these outbreaks.Methods: RVF epizootic records obtained from the World Animal Health Information Database (WAHID), documenting livestock species affected, location, and time, were analyzed. Environmental variables including rainfall and satellite-derived normalized difference vegetation index (NDVI) data were collected and assessed in outbreak regions to understand the underlying drivers of the outbreaks.Results: The predominant domestic vertebrate species affected in 2008 and 2009 were cattle, when outbreaks were concentrated in the eastern provinces of South Africa. In 2010 and 2011, outbreaks occurred in the interior and southern provinces affecting over 16,000 sheep. The highest number of cases occurred between January and April but epidemics occurred in different regions every year, moving from the northeast of South Africa toward the southwest with each progressing year. The outbreaks showed a pattern of increased rainfall preceding epizootics ranging from 9 to 152 days; however, NDVI and rainfall were less correlated with the start of the outbreaks than has been observed in eastern Africa.Conclusions: Analyses of the multiyear RVF outbreaks of 2008 to 2011 in South Africa indicated that rainfall, NDVI, and other environmental and geographical factors, such as land use, drainage, and topography, play a role in disease emergence. Current and future investigations into these factors will be able to contribute to improving spatial accuracy of models to map risk areas, allowing adequate time for preparation and prevention before an outbreak occurs.

Evidence for climate-induced range shift in Brachystegia (miombo) woodland

Brachystegia spiciformis Benth. is the dominant component of miombo, the sub-tropical woodlands which cover 2.7 million km2 of south-central Africa and which is coincident with the largest regional centre of endemism in Africa. However, pollen records from the genus Brachystegia suggest that miombo has experienced rapid range retraction (~450 km) from its southernmost distributional limit over the past 6000 years. This abrupt biological response created an isolated (by ~200 km) and incomparable relict at the trailing population edge in northeast South Africa. These changes in miombo population dynamics may have been triggered by minor natural shifts in temperature and moisture regimes. If so, B. spiciformis is likely to be especially responsive to present and future anthropogenic climate change. This rare situation offers a unique opportunity to investigate climatic determinants of range shift at the trailing edge of a savannah species. A niche modelling approach was used to produce present-day and select future B. spiciformis woodland ecological niche models. In keeping with recent historical range shifts, further ecological niche retraction of between 30.6% and 47.3% of the continuous miombo woodland in Zimbabwe and southern Mozambique is predicted by 2050. Persistence of the existing relict under future climate change is plausible, but range expansion to fragmented refugia in northeast South Africa is unlikely. As Brachystegia woodland and associated biota form crucial socio-economic and biodiversity components of savannas in southern Africa, their predicted further range retraction is of concern.