Anthrax is a globally significant animal disease and zoonosis. Despite this, current 57 knowledge of anthrax ecology is largely limited to arid ecosystems, where outbreaks 58 are most commonly reported 1-3. We reveal the dynamics of an anthrax causing 59 agent, Bacillus cereus biovar anthracis, in a tropical rainforest with severe 60 consequences for local wildlife communities. Using data and samples collected over 61 three decades we find that rainforest anthrax is a persistent and widespread cause 62 of death for a broad range of mammalian hosts. We predict that this pathogen will 63 accelerate the decline and possibly result in the extirpation of local chimpanzee (Pan 64 troglodytes verus) populations. Our findings illuminate the epidemiology of a cryptic 65 pathogen and have important implications for conservation. 66 67 Anthrax is a disease of wildlife, livestock and humans predominantly affecting low and 68 middle-income countries 2,4,5. Although widely distributed, including some temperate 69 regions, anthrax is most commonly associated with arid ecosystems, particularly African 70 3 savannas 1,3,6-11. In these systems, major outbreaks typically cause high mortality in a few 71 wild and domestic ungulate species at a time and usually exhibit strong seasonal and 72 inter-annual variation 2,3,5,11,12. For example, in Krüger National Park, South Africa, die-73 offs in kudus (Tragelaphus strepsiceros) and impalas (Aepyceros melampus) occur in the 74 dry season with a ten year periodicity coinciding with rainfall cycles 11. In Etosha 75 National Park, Namibia, mortality in elephants (Loxodonta Africana) peaks at the start of 76 the wet season, while plains ungulates (Equus quagga, Conochaetes taurineus, 77 Antidorcas marsupialis) are most affected at the end of the wet season 3,13. Such varying 78 dynamics underline the importance of investigating the pathogen in close relation with its 79 ecosystem, but so far anthrax research in Africa has been biased towards well-studied 80 savanna regions. 81 In 2001, lethal anthrax-like cases in wild chimpanzees were reported in a rainforest 82 habitat: Taï National Park (TNP), Côte d'Ivoire (Fig. S1) 14. The causative agent was a 83 bacterium combining the chromosomal background of Bacillus cereus with the virulence 84 plasmids of B. anthracis (Bacillus cereus biovar anthracis; Bcbva) 15. Pathology and 85 histopathology of Bcbva cases were clearly suggestive of anthrax and in small animal 86 models Bcbva was as virulent as B. anthracis 14-16. Bcbva cases have since been described 87 in animals in Cameroon (CM), Central African Republic (CAR) and the Democratic 88 Republic of Congo 17,18 , suggesting a broad sub-Saharan distribution (Fig. 1). However, 89 the epidemiology of anthrax-like disease caused by Bcbva (hereafter anthrax), and to 90 what extent it matches that of classical anthrax, remain poorly understood. 91 We address this knowledge gap by testing a unique set of samples collected in TNP over 92 26 years. We started collecting bones in 1989 resulting in bones f...

Bovine tuberculosis (BTB) was first detected in Kruger National Park (KNP) in a single African buffalo (Syncerus caffer) in 1990. In 1991/1992, 2,071 African buffalo were examined for BTB as part of a culling program that removed animals from all known herds in KNP. The prevalence of BTB in 1991/1992 was estimated to be 0%, 4.4% (+/-0.6%), and 27.1% (+/-1.4%), in the north, central, and south zones of KNP, respectively. In 1998, a stratified, two-stage cluster sampling method was used to estimate that the prevalence of BTB was 1.5% (+/-2.5%), 16% (+/-5.3%), and 38.2% (+/-6.3%), in the north, central, and south zones, respectively. This represented a significant increase in prevalence (P < or = 0.05) in the south and central zones, but not in the north zone. Continued monitoring of BTB in KNP is important for understanding disease transmission risks, potential population effects, and the efficacy of disease management strategies. The methodology and sample sizes used in 1998 are appropriate for future BTB monitoring in KNP.

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It has only recently been possible to detect sufficient genetic diversity among anthrax isolates to allow genotype grouping ( Keim et al. 1997 ). Early results of such grouping suggest that the southern African subcontinent may be the geographical origin of Bacillus anthracis. This report describes a pilot investigation of the genetic diversity of a study group of isolates from the Kruger National Park, South Africa, and efforts to detect spatio‐temporal clustering within the study group. This study has also served as further validation for the newly developed Multi‐Locus VNTR Analysis (MLVA), designed to simplify genotyping of B. anthracis isolates. The results reveal a diverse range of genotypes within the park allied with three genotype reference groups, and show that the MLVA procedure is robust for rapid analysis of B. anthracis genotypes. We also observed multiple genotype groups within epidemics and between geographically and temporally close epidemic episodes. This is in contrast to earlier characterizations of anthrax epidemics. The result of a Mantel test for time–space clustering indicates clustering of the anthrax isolates selected for the study.