surveillance efforts focus on risk for humans, mountain Human gorillas are immunologically naive and susceptible to with human pathogens. The parks in which mountain gorillas live are surrounded by the densest human populations in continental Africa. In addition, research and Infection in Wild gorilla ecotourism brings thousands of persons from the local communities and from around the world into direct Mountain Gorillas, and indirect contact with the gorillas. The frequency and Rwanda closeness of contact is particularly pronounced in Virunga National Park, where 75% of mountain gorillas are Gustavo Palacios, Linda J. Lowenstine, habituated to the presence of humans. Michael R. Cranfi eld, Kirsten V.K. Gilardi, Lucy To minimize the threat of disease , the Spelman, Magda Lukasik-Braum, Rwandan, Ugandan, and Congolese governments restrict Jean-Felix Kinani, Antoine Mudakikwa, tourist numbers and proximity, and the Congolese wildlife Elisabeth Nyirakaragire, Ana Valeria Bussetti, authority mandates that masks be worn by persons visiting Nazir Savji, Stephen Hutchison, Michael Egholm, gorillas. Nonetheless, the frequency and severity of and W. Ian Lipkin respiratory disease outbreaks among mountain gorillas in the Virunga Massif have recently increased. From May The genetic relatedness of mountain gorillas and through August 2008, sequential respiratory outbreaks humans has led to concerns about interspecies transmission of infectious agents. Human-to-gorilla transmission may occurred in 4 groups of mountain gorillas accustomed to explain human metapneumovirus in 2 wild mountain gorillas tourism in Rwanda. Between June 28 and August 6, 2009, that died during a respiratory disease outbreak in Rwanda a fi fth outbreak occurred in 1 of these groups, Hirwa. in 2009. Surveillance is needed to ensure survival of these We describe the Hirwa outbreak. Respiratory outbreaks critically endangered animals. were defi ned as more than one third of animals in a group exhibiting signs of respiratory disease (coughing, oculonasal discharge, and/or lethargy). he world’s remaining 786 mountain gorillas (Gorilla beringei beringei) live in 2 parks in Rwanda, Uganda, T The Cases and the Democratic Republic of the Congo. An ecotourism The Hirwa group consisted of 12 animals: 1 adult industry for viewing human-habituated mountain gorillas male, 6 adult females, 3 juveniles, and 2 infants. Moderate in the wild is thriving in all 3 countries. Mountain gorilla to severe respiratory disease (>2 characteristic signs) tourism helps ensure the sustainability of the species by developed in 11 of 12 animals. Five (3 juvenile males generating much-needed revenue and increasing global and 2 adult females) received antimicrobial drug therapy awareness of the precarious status of this species in the (ceftriaxone, 50 mg/kg for adults, 100 mg/kg for infants), wild. Tourism, however, also poses a risk for disease 4 by remote delivery and 1 while chemically immobilized. transmission from humans to the gorillas. Two untreated animals (1 adult female and 1 male infant Habitat encroachment and poaching are threats to born to a symptomatic mother) died. On June 30, the adult wildlife survival, particularly in the developing world. female was fi rst observed coughing and lethargic but still Mountain gorillas face an additional threat from infectious feeding. On July 3, she left her night nest in the morning diseases. Second only to trauma, infectious diseases, but did not join her group; she exhibited severe clinical primarily respiratory, account for 20% of sudden deaths signs and was found dead on July 4 at ≈1:00 PM. The infant (1). The close genetic relatedness of mountain gorillas and was 3 days old when it died on July 23. Clinical signs of humans has led to concerns about the potential interspecies respiratory illness had not been observed, although its transmission of infectious agents (2,3). Although most mother showed severe clinical signs for 2–3 days before Author affi liations: Columbia University, New York, New York, USA and after delivery; before delivery, she had received (G. Palacios, A. Valeria Bussetti, N. Savji, W.I. Lipkin); University of antimicrobial drugs by remote delivery (neither she nor her California, Davis, California, USA (L.J. Lowenstine, M.R. Cranfi eld, infant were handled by humans). K.V.K. Gilardi); Mountain Gorilla Veterinary Project, Davis (L. Gross postmortem examinations revealed broncho- Spelman, M. Lukasik-Braum, J.-F. Kinani); Rwanda Development in the adult and unilateral pulmonary congestion Board, Kigali, Rwanda (A. Mudakikwa, E. Nyirakaragire); and and an empty stomach in the infant. Formalin-fi xed (10%) 454 Life Sciences, Branford, Connecticut, USA (S. Hutchison, M. postmortem tissue samples from the adult and infant were Egholm) prepared in 6 μm sections for histologic studies, stained DOI: 10.3201/eid1704100883 with hematoxylin and eosin according to standard methods,

Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 4, April 2011 711 DISPATCHES and examined by light microscopy. Histologically, the HMPV (4). Bayesian analysis revealed close relationship respiratory tract of the adult was characterized by moderate of the gorilla to human isolates from South Africa mononuclear tracheitis, laryngitis, and air sacculitis; (Figure). Sequence information for the reported HMPV severe pulmonary alveolar histiocytosis; multifocal has been deposited with GenBank under accession no. severe suppurative pneumonia; and multifocal pulmonary HM197719. Detailed methods are available in the online thrombosis and hemorrhage. One section of lung from the Technical Appendix (www.cdc.gov/EID/content/17/4/zzz- infant showed pulmonary atelectasis, congestion, mild Techapp.pdf). alveolar hemorrhage, and histiocytosis. The infant also had moderate neutrophil and macrophage infi ltration of Conclusions the umbilicus at the body wall; neutrophilic infl ammation Experimental of cynomologus macaques in the media and adventitia of 1 umbilical artery at the with HMPV have suggested that pure infection with this level of the bladder; and mild, unilateral, focal, segmental, virus causes minimal to mild lesions in conducting airways neutrophilic glomerulitis and tubulointerstitial nephritis. and increased macrophages in alveoli (5). However, Coronary groove and mesenteric fat were absent. paramyxoviruses, including HMPV, can predispose Multiplex PCR analysis for respiratory pathogens animals to bacterial pneumonia (6–8), as appeared to be indicated sequences of human metapneumovirus (HMPV) the case in the adult female mountain gorilla reported here. in serum; lung tissue; and throat, nose, anus, and vagina That HMPV can be fatal for gorillas is supported by a swabs from the adult gorilla, and in lung tissue from the report of a respiratory outbreak in wild, human-habituated infant (Table). Streptococcus pneumoniae was detected chimpanzees in which several chimpanzees died (2,9). in lung tissue and in throat and nose swabs of the adult We report conclusive evidence for association of a gorilla but not in the infant. Klebsiella pneumoniae was human virus with death in mountain gorillas (2,3). Viral also detected in all specimens from the adult gorilla. RNA in multiple tissue samples from the adult female Microbial loads were determined by quantitative PCR indicates that she was infected by an HMPV strain at (Table). The sample with the highest viral load, a throat the time of her death. The upper respiratory lesions were swab from the adult female (6.2 × 105 genome copies/μL), suggestive of a viral infection (9). The pulmonary lesions was pyrosequenced, yielding 607,484 reads comprising 3.8 indicated a bacterial bronchopneumonia as the proximate kb of sequence (27.5% of the genome). Simple pairwise cause of death, compatible with an etiologic agent such as S. analysis indicated that the strain belonged to lineage B2 of pneumoniae and K. pneumoniae, the 2 organisms detected

Table. Results of microbiologic testing of mountain gorilla tissues, Rwanda* HMPV viral Bacterial load, genome copies/μL Sample source MassTag RNA load, genome MassTag DNA Streptococcus Klebsiella and no. Sample type panel results copies/μL panel results pneumoniae pneumoniae Adult 1 Serum HMPV 2.7 u 103 K. pneumoniae ND 3.2 u 107 2 Buffy coat Negative ND K. pneumoniae ND 4.4 u 108 3 Kidney Negative ND K. pneumoniae ND 6.2 u 108 4 Lung HMPV 3.2 u 102 S. pneumoniae, 1.3 u 102 2.0 u 107 K. pneumoniae 5 Heart Negative ND K. pneumoniae ND 1.4 u 107 6 Spleen Negative ND K. pneumoniae ND 9.1 u 105 7 Liver Negative ND K. pneumoniae ND 3.1 u 105 8 Throat swab HMPV 6.2 u 105 S. pneumoniae, 5.5 u 104 1.4 u 105 K. pneumoniae 9 Nasal swab HMPV 2.3 u 105 S. pneumoniae, 4.3 u 104 2.4 u 106 K. pneumoniae 10 Vaginal swab HMPV 2.0 u 102 K. pneumoniae ND 6.0 u 105 11 Anal swab HMPV 4.0 u 102 K. pneumoniae ND 5.5 u 102 12 Purulent Negative ND K. pneumoniae ND 5.2 u 102 discharge Infant 18 Spleen Negative ND Negative ND ND 19 Lung HMPV <5.0 u 101 Negative ND ND 20 Liver Negative ND Negative ND ND 21 Kidney Negative ND Negative ND ND *HMPV, human metapneumovirus; ND, not detected.

712 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 17, No. 4, April 2011 HMPV Infection in Wild Mountain Gorillas, Rwanda

US Agency for International Development Predict funding source code 07-301-7119-52258 (Center for Infection and Immunity), US Agency for International Development Predict Emerging Pandemic Threats (University of California, Davis), and a grant from the David and Lucile Packard Foundation to the Mountain Gorilla One Health Program. Dr Palacios is assistant professor of clinical epidemiology at the Center for Infection and Immunity, Mailman School of Public Health, Columbia University, New York. His primary research interests are molecular epidemiology of viral infections, virus surveillance, and pathogen discovery.

References

1. Mudakikwa A, Cranfi eld M, Sleeman J, Eilenberger U. Clinical medicine, preventive health care and research on mountain gorillas in the Virunga Volcanoes region. In: Robbins M, Sicotte P, Stewart K, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (UK): Cambridge University Press; 2001. p. 341–60. Figure. Bayesian analysis of the G gene of human metapneumovirus 2. Köndgen S, Kuhl H, N’Goran PK, Walsh PD, Schenk S, Ernst N, et (HMPV) isolated from an adult female mountain gorilla that died al. Pandemic human cause decline of endangered great apes. during an outbreak of respiratory disease, Rwanda. Bayesian Curr Biol. 2008;18:260–4. DOI: 10.1016/j.cub.2008.01.012 phylogenetic analyses of sequence differences of the HPMV 3. Hastings B, Kenny D, Lowenstine L, Foster J. Mountain gorillas and glycoprotein gene were conducted by using BEAST, BEAUti, and measles: ontogeny of a wildlife vaccination program. Procceedings Tracer analysis software packages (http://beast.bio.ed.ac.uk/Main_ of the American Association of Zoo Veterinarians. 1991:198–205. Page). Only lineage B2 HMPVs are shown. The black dot indicates 4. de Graaf M, Osterhaus AD, Fouchier RA, Holmes EC. Evolution- the strain newly isolated from the gorilla; trees are rooted at the ary dynamics of human and avian metapneumoviruses. J Gen Virol. midpoint; scale is in years. An expanded version of this fi gure, 2008;89:2933–42. DOI: 10.1099/vir.0.2008/006957-0 showing the complete HMPV gene analysis, is available online 5. Kuiken T, van den Hoogen BG, van Riel DA, Laman JD, van Am- (www.cdc.gov/EID/content/17/5/711-F.htm). erongen G, Sprong L, et al. Experimental human metapneumovirus infection of cynomolgus macaques (Macaca fascicularis) results in virus replication in ciliated epithelial cells and pneumocytes with associated lesions throughout the respiratory tract. Am J Pathol. by PCR. Although the cause of death of the infant was likely 2004;164:1893–900. DOI: 10.1016/S0002-9440(10)63750-9 inanition and acute dissemination of an umbilical infection 6. Kukavica-Ibrulj I, Hamelin ME, Prince GA, Gagnon C, Bergeron to a kidney, detection of HMPV as the sole pathogen in Y, Bergeron MG, et al. Infection with human metapneumovirus predisposes mice to severe pneumococcal pneumonia. J Virol. the infant tissues supports the presence of this agent in the 2009;83:1341–9. DOI: 10.1128/JVI.01123-08 gorilla group during the respiratory disease outbreak. 7. Jones EE, Alford PL, Reingold AL, Russell H, Keeling ME, Broome The source of the virus is unknown; the strain was CV. Predisposition to invasive pneumococcal illness following para- most recently described in South Africa. The 2 HMPV- infl uenza type 3 virus infection in chimpanzees. J Am Vet Med As- soc. 1984;185:1351–3. positive animals were not handled by veterinarians or 8. Szentiks CA, Kondgen S, Silinski S, Speck S, Leendertz FH. Lethal park personnel during the course of their illness. Although pneumonia in a captive juvenile chimpanzee (Pan troglodytes) due HMPV transmission as a result of human intervention to human-transmitted human respiratory syncytial virus (HRSV) to treat sick animals in the group is possible, it does not and infection with Streptococcus pneumoniae. J Med Primatol. 2009;38:236–40. DOI: 10.1111/j.1600-0684.2009.00346.x explain HMPV in the adult female, which died early in the 9. Kaur T, Singh J, Tong S, Humphrey C, Clevenger D, Tan W, et al. outbreak before any clinical interventions were conducted. Descriptive epidemiology of fatal respiratory outbreaks and detec- Although human proximity to mountain gorillas is essential tion of a human-related metapneumovirus in wild chimpanzees (Pan for their conservation, also crucial is minimizing the risk for troglodytes) at Mahale Mountains National Park, Western Tanzania. Am J Primatol. 2008;70:755–65. DOI: 10.1002/ajp.20565 human-to–great ape transmission of respiratory pathogens. Address for correspondence: Gustavo Palacios, Center for Infection and This work was supported by Google.org, National Institutes Immunity, Columbia University, Rm 1709, 722 W 168th St, New York, of Health award AI57158 (Northeast Biodefense Center to W.I.L), NY 10032, USA; email: [email protected] Search past issues of EID at www.cdc.gov/eid

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