Descriptive epidemiology of fatal respiratory outbreaks and detection of a human-related metapneumovirus in wild chimpanzees (Pan troglodytes) at Mahale Mountains National Park, Western Tanzania.
Over the past several years, acute and fatal respiratory illnesses have occurred in the habituated group of wild chimpanzees at the Mahale Mountains National Park, Tanzania. Common respiratory viruses, such as measles and influenza, have been considered possible causative agents; however, neither of these viruses had been detected. During the fatal respiratory illnesses in 2003, 2005 and 2006, regular observations on affected individuals were recorded. Cause-specific morbidity rates were 98.3, 52.4 and 33.8%, respectively. Mortality rates were 6.9, 3.2 and 4.6%; all deaths were observed in infants 2 months-2 years 9 months of age. Nine other chimpanzees have not been seen since the 2006 outbreak and are presumed dead; hence, morbidity and mortality rates for 2006 may be as high as 47.7 and 18.5%, respectively. During the 2005 and 2006 outbreaks, 12 fecal samples were collected from affected and nonaffected chimpanzees and analyzed for causative agents. Analysis of fecal samples from 2005 suggests the presence of paramyxovirus, and in 2006 a human-related metapneumovirus was detected and identified in an affected chimpanzee whose infant died during the outbreak. Our findings provide preliminary evidence that the causative agent associated with these illnesses is viral and contagious, possibly of human origin; and that, possibly more than one agent may be circulating in the population. We recommend that baseline health data be acquired and food wadge and fecal samples be obtained and bio-banked as early as possible when attempting to habituate new groups of chimpanzees or other great apes. For already habituated populations, disease prevention strategies, ongoing health monitoring programs and reports of diagnostic findings should be an integral part of managing these populations. In addition, descriptive epidemiology should be a major component of disease outbreak investigations.
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia 24061, USA. taranjit@vt.edu
Taranjit
T
Kaur
Jatinder
J
Singh
Suxiang
S
Tong
Charles
C
Humphrey
Donna
D
Clevenger
Wendy
W
Tan
Brian
B
Szekely
Yuhuan
Y
Wang
Yan
Y
Li
Epaphras
E
Alex Muse
Mieko
M
Kiyono
Shunkichi
S
Hanamura
Eiji
E
Inoue
Michio
M
Nakamura
Michael A
MA
Huffman
Baoming
B
Jiang
Toshisada
T
Nishida
D017677:Age Distribution; D000818:Animals; D018420:Ape Diseases / Q000453:epidemiology / Q000401:mortality / Q000821:virology*; D004196:Disease Outbreaks / Q000662:veterinary*; D005243:Feces / Q000821:virology; D005260:Female; D008297:Male; D029121:Metapneumovirus / Q000302:isolation & purification*; D002679:Pan troglodytes; D018184:Paramyxoviridae Infections / Q000453:epidemiology / Q000401:mortality / Q000662:veterinary*; D012140:Respiratory Tract Diseases / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D013636:Tanzania; D013997:Time Factors