Abstract
A flu-like disease spread among chimpanzees (Pan troglodytes schweinfurthii) of the M group at Mahale Mountains National Park, Tanzania, from June to July 2006. This epizootic or epidemic killed up to 12 chimpanzees. The obvious evidence of their deaths came from finding the bodies of three infants who had previously shown some symptoms of the disease. At least one of these infants died of pneumonia. In addition, nine chimpanzees were missing after the outbreak. These individuals were assumed to have been killed by this epizootic because most of them had contact with the infected individuals on the last days they were observed. We also found two dead bodies during this period, which were thought to be those of two missing individuals. We confirmed 23 (35.4%) of 65 individuals of the M group showed some symptoms of the disease, although most of them (20/23) did not die. More than half of them (14/23) had kin showing symptoms. Since this epizootic may have been caused by contact with humans, it will be necessary to establish and follow appropriate protocols for researchers, tourists, and park staff to observe chimpanzees, and to explore the mechanism of disease transmission from humans to chimpanzees and among chimpanzees.
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Acknowledgments
We thank COSTECH, TAWIRI, TANAPA and Mahale Mountains National Park for permission to conduct research; R. Kitopeni and M. Matumula for assisting in the research; A. H. Harcourt and K. N. Cameron for useful comments; and H. Y. Kayumbo, T. Nemoto, and A. Inaba for encouragement. This study was financed by MEXT Grants-in-Aid for Scientific Research (#16255007 to TN and #16770186 to MN) and a Global Environment Research Fund (F-061 to TN) from the Ministry of Environment.
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Hanamura, S., Kiyono, M., Lukasik-Braum, M. et al. Chimpanzee deaths at Mahale caused by a flu-like disease. Primates 49, 77–80 (2008). https://doi.org/10.1007/s10329-007-0054-1
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DOI: https://doi.org/10.1007/s10329-007-0054-1