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Journal of Wildlife Di.seases, 29)1), 1993, pp. 109-113

© Wildlife Disease Association 1993 Evidence of Poxvirus in Dusky ( obscurus) and Burmeister’s ( spinipinnis) from Coastal Peru

Marie-Fran#{231}oise Van Bressem,12 Koen Van Waerebeek,2 Julio C. Reyes,2 Daniel Dekegel,3 and Paul-Pierre

Pastoret, 1 Department of Virology and Immunology, Faculty of Veterinary Medicine, University of Liege, Institut de

Chimie, Batiment B6, Local R80, Sart Tilman, 4000 Liege, Belgium; 2 Centro Peruano de Estudios Cetol#{243}gicos, do Grupo Cet#{225}ceos-Asociaci#{243}n de Ecologia y Conservaci#{243}n, Casilla 1536, Lima 18, Peru; Department of Electron Microscopy, Pasteur Institute of Brabant, 45 rue Engeland, B-i 180 Brussels, Belgium

ABSTRACT: In 1990, 74 dusky (La- haus et al., 1990) and harbor seals (Phoca genorhynchus obscurus) and 10 Burmeister’s vitulina) (Wilson et a!., 1972). In these (Phocoena spinipinnis) were exam- species, visible lesions consisted mainly of ined for the presence of hyperpigmented marks elevated skin nodules. and pinhole lesions on the skin (tattoo lesions) at the fishing terminal of Pucusana, central Peru. In dolphins, poxvirus infection is char- Prevalences of tattoo lesions were 8.1% and 30% acterized by hyperpigmented marks on the in the dolphins and porpoises, respectively. In- skin, flat or slightly in relief, or by “pin- tracytoplasmic poxviruses were demonstrated hole” lesions, collectively known as “tat- by transmission electron microscopy in ultrathin sections of three of eight samples of infected toos” (Dailey, 1985), and has been de- epidermis from both species. The reason for the scribed from captive and free-ranging negative results in others is unclear but may be bottlenose dolphins (Tursiops truncatus) related to stages of infection with low virus den- (Geraci et a!., 1979; Fbom and Houk, 1979), sity or even incorrect classification of some le- free-ranging common dolphins (Delphi- sions as genuine viral tattoos. An irregular ar- rangement of tubules on the outer viral nus deiphis) (Britt and Howard, 1983) and membrane, similar to those in orthopoxviruses, an Atlantic white-sided dolphin (Lage- was visible in negative contrast preparations for norhynchus acutus) (Geraci et a!., 1979). P. spinipinnis. This is the first record of poxvirus All were from the North Atlantic, in porpoises (Phocoenidae) and also the first re- except the common dolphins (Britt and port for dusky dolphins, and generally for ce- taceans of the . Howard, 1983). Key words: Dusky dolphin, Burmeister’s Here we report the identification and porpoise, Lagenorhynchus obscurus, Phocoena preliminary prevalence levels of poxvirus spinipinnis, dolphmnpox virus, cetacean tattoo in the dusky dolphin (Lagenorhynchus oh- lesions. scurus) and Burmeister’s porpoise (Pho- coena spinipinnis) from waters off central Among marine , poxviruseS Peru. In this region, large numbers of small infect both and dolphins. Among cetaceans are killed incidently in a coastal pinnipeds, pox lesions have been reported giblnet fishery and are sold commercially from Californian sea lions (Zalophus cal- for human consumption (Read et a!., 1988; ifornianus) (Wilson et a!., 1969), South Van Waerebeek and Reyes, 1990). From American sea lions (Otaria byronia) (Wil- 1984 to 1990, skin lesions recognized as son and Poglayen-Neuwaib, 1971), north- tattoos regularly were seen in animals ern fur seals (Callorhinus ursinus) (Had- landed at local markets. In 1990, an bow et a!., 1980), grey seals (Halichoerus investigation of tattoo skin lesions was gry pus) (Hicks and Worthy, 1987; Oster- started in the context of ongoing research

109 110 JOURNAL OF WILDLIFE DISEASES, VOL. 29, NO. 1, JANUARY 1993

TABLE 1. Occurrence of tattoo skin lesions and poxvirus in dusky dolphins (Lagenorhynchus obscurus) and Burmeister’s porpoises (Phocoena spinipinnis) from Peruvian coastal waters. Examination by transmission electron microscopy in ultrathin section (UT) and negative contrast preparation (NC).

Stan- dard body Necropsy length

Species number Sex (mm) UT NC Description

L. obscurus MFB-001 M 1,805 + ND” Numerous tattoo lesions dispersed on head, trunk and flippers

MFB-012 F 1,555 - ND Irregular dark mark showing some red spots in front of the right flipper

MFB-044 F 1,625 - ND Dark mark with pinhole lesions located behind left eye

MFB-045 F 1,965 - ND Small abraded lesion (5 mm) on left side of tail stock

MFB-046 F 1,860 - ND Dark mark (12 by 7 mm) with pinhole lesions on left side of tail stock MFB-063 F 1,550 ND ND Numerous tattoos, some presenting pin- hole lesions and petechia

P. spinipinnis KVW-2282 F 1,705 - - Extensive blackish tattoo marks over en- tire body; largest (65 by 52 mm) locat- ed behind left eye and slightly raised KVW-2283 F 1,545 ND + Two tattoo lesions on the chin and on right lower lip KVW-2291 M 1,460 + + One tattoo mark on the left flank at mid- body

+, presence of poxvirus; -, absence of poxviruses.

ND, this procedure not done on this . on the biology of small cetaceans in the dermis and dermis, was excised from an- eastern South Pacific. imals with tattoo lesions and fixed in 5% Seventy-four dusky dolphins (38 fe- glutaraldehyde buffered with 0.1 M caco- males, 30 males, 6 of unknown sex) and dybate (pH 6.8) (Millonig, 1976). An ad- 10 Burmeister’s porpoises (5 females, 5 ditional set of porpoise skin samples was males) were carefully examined for the soaked in 40% glycerin (Mclbvaine buffer) presence of tattoo lesions at the fishing ter- (Hodgman, 1946) and frozen at -10 C for minal of Pucusana (12#{176}30’S, 76#{176}44’W), posterior negative contrast preparation and Peru, in August, September and December virus isolation. Samples were prepared for 1990. The mean standard body length electron microscopy according to the pro- (SBL) of a!! dolphins was 1,738 mm (SE = cedures of Glauert (1975): preparations of 19 mm); the range was 1,415 to 2,030 mm. skin lesion kept in glycerin were nega- The mean SBL for the porpoises was 1,525 tively stained with uranyb acetate and post- mm (SE = 38 mm), and the range was fixed with osmium tetroxide; glutaralde- 1,355 to 1,725 mm. The animals either hyde fixed samples were stained with drowned or asphyxiated after gilbnet en- uranyl acetate and embedded in a mixture tanglement, and were sampled 6 to 18 hr of Epon and Spurr resin (Glauert, 1975). post-mortem. Although necropsies were not Semi-thin sections (2 tim) were examined permitted by fishmongers, a rough indi- with an anoptral phase contrast micro- cation of their general health status was scope (Reichert, Vienna, Austria) to local- derived from external clues, in particular ize tissues, and ultra-thin sections (Reich- signs of emaciation. ert Ubtracut microtome, Vienna, Austria) About 1 cm2 of skin, including epi- were stained with lead citrate. All prepa- SHORT COMMUNICATIONS 111

FIGURE 2. Section through mature (V) and im- mature (I) particles. Dumb-bell shaped core sur- rounded by two lateral bodies and enclosed by an FICI-IIE 1. Cluster of mature (V) and immature outer membrane is visible in mature virions. (I) poxvirus particles in cytoplasm of infected epi- thelial cell of a dusky dolphin from Peru (MFB-001). Note irregular membrane of the nucleus (N) and Poxviruses visible by TEM in negative con- margination of chromatin. trast preparations in two (KVW-2283, KVW-2291) of three porpoises (Table 1) rations were examined with a Siemens 102 had an irregular arrangement of tubules transmission electron microscope (Sie- on the outer membrane (Fig. 3). mens, Berlin, Germany) at 100 kV. Although further characterization is Confidence bevels (CL: 95%) were cal- necessary, the poxviruses described here culated according to the normal approxi- were morphobogically similar to orthopox- mation rube for proportions (Wonnacott viruses (Fenner et al., 1987). They were and Wonnacott, 1990). readily distinguished from the classical Skin lesions resembling tattoos (Fbom and sealpox virus, which has a regular spiral Houck, 1979; Geraci et a!., 1979) were ob- arrangement of tubules and belongs to the served in six (8.1%) of the 74 dusky dol- parapoxviridae (Fenner et a!., 1987). phins (CL: 1.8 to 14.4%) and three of the Therefore, the pox disease encountered in ten Burmeister’s porpoises (Table 1). Two South American sea lions of Peru (Wilson dusky dolphins and one porpoise had nu- and Pogbayen-Neuwabb, 1971) probably was merous tattoo marks dispersed over their not etiobogically related to the poxvirus in- head, trunk and flippers; in the others, fection in the dusky dolphin and Bur- marks were few and isolated (Table 1). meister’s porpoise from the same waters. Lesions included hyperpigmented rings So far, orthopoxvirus associated with para- and black stippled patterns. Petechia were observed on the dark outline of some rings in two dolphins. None of the affected an- imals was emaciated, nor were there any other signs of reduced body condition. Webb-defined, dense clusters of intra- cvtopbasmic poxviruses were revealed by transmission electron microscopy (TEM) in the ultrathin sections of the epidermis

in one (MFB-001) of five dusky dolphins and one (KVW-2291) of two porpoises ex- F1;URE 3. Poxviruses in negatively stained prep- amined (Table 1). Viral particles, about arations of tattoos in Burmeister’s porpoises (KVW- 250 by 200 nm, were morphobogicably 2283) showing an irregular arrangement of tubules identical in both cetaceans (Figs. 1, 2). on the outer viral membrane, as in orthopoxviruses. 112 JOURNAL OF WILDLIFE DISEASES, VOL. 29, NO. 1, JANUARY 1993 poxvirus has been reported only in skin and Dr. M. Kbinowska for critical com- lesions of grey seals (Osterhaus et a!., 1990). ments on the manuscript. Field work by it is unclear why viruses were found in KVW and JCR was supported in part by TEM preparations of tattoo lesions from grants from the Whale and Dolphin Con- only three animals. Possibly different stages servation Society, Leopold Ill-Fonds voor of infection vary widely in density of virus Natuuronderzoek en Natuurbehoud, Van clusters; perhaps some tattoo-like lesions Tienhoven Foundation and BBC Wildlife collected were not of poxvirus origin. Magazine. The present sample size of Burmeister’s porpoises was too small to compare prey- LITERATURE CITED alences between this species and dusky BRITT, J. 0., AND E. B. HOWARD. 1983. Virus dis- dolphins. Nevertheless, earlier opportunis- eases. In Pathobiology of marine dis- tic observations by two coauthors (KVW eases, Vol. 1, E. B. Howard (ed). CRC Press, and JCR) seemed to coincide with a higher Boca Raton, Florida, pp. 47-67. prevalence in porpoises as suggested by the DAILEY, M. D. 1985. Diseases of mammalia: Ce- present data. Future work should encom- tacea. In Diseases of marine animals, Vol. 4, part 2, 0. Kinne (ed). Biologische Anstalt Helgoland, pass more animals and include other com- Hamburg, Federal Republic of Germany, pp. monly captured small cetaceans, such as 805-848. the and the bottlenose FENNER, F. 1990. Poxviruses. In Virology, 2nd ed., dolphin (Read et a!., 1988; Van Waerebeek B. N. Fields, D. M. Knippe, H. M. Chanock, M. et a!., 1990) and also other localities. Pox- S. Hirsch, T. P. Monath, and B. Roizman (eds.). virus infection patterns possibly could serve Raven Press, New York, New York, pp. 2113- 2133. as a biological tag to help discriminate sep- P. A. BACHMANN, E. P. J. GIBBS, F. A. arate populations, and thus provide useful MURPHY, M. J. STUDDERT, AND D. 0. WHITE. information for management purposes. 1987. Veterinary virology. Academic Press Inc.,

Among cetaceans, poxviruses have been San Diego, California, pp. 387-405. FLOM, J. 0., AND E. J. HOUK. 1979. Morphologic reported only from delphinids and even evidence of poxvirus in ‘tattoo” lesions from cap- then documented accounts from free- tive bottlenosed dolphins. Journal of Wildlife ranging dolphins are rare (Geraci et a!., Diseases 15: 593-596. 1979), perhaps because little attention is GERACI, J. H., B. D. HICKS, AND D. J. ST. AUBIN. paid to such lesions. The present account 1979. Dolphin pox: A skin disease of cetaceans. is the first record of poxvirus infection in Canadian Journal of Comparative Medicine 43: 399-404. a porpoise (family Phocoenidae). It also is GLAUERT, A. M. 1975. Embedding. In Fixation, the first report for L. obscurus, for ceta- dehydratation and embedding of biological spec- ceans of the southeast Pacific Ocean and imens. Practical methods in electron microscopy, for the southern hemisphere. Vol. 3, part 1, A. M. Glauert (ed). North Holland Poxviruses commonly cause disease in Publishing Company, Amsterdam, Holland, pp. 123-176. human beings (Hicks and Worthy, 1987; HADLOW, W. J., N. F. CHEvILLE, AND W. L. JEL- Fenner, 1990). The extensive handling and LISON. 1980. Occurrence of pox in a northern consumption of thousands of small ceta- fur seal on the Pribilof Islands. Journal of Wild- ceans by Peruvians each year thus raises life Diseases 16: 305-312. HICKS, B. D., AND C. A. WORTHY. 1987. Sealpox the question of whether dobphinpox may in captive grey seals (Halichoerus grypus) and have a public health significance. Indeed, their handlers. Journal of Wildlife Diseases 23: mild manifestations of an infection could 1-6. easily go unnoticed among those social HODGMAN, C. D. 1946. Handbook of chemistry and groups which for economic reasons do not physics, 30th ed. Chemical Rubber Publishing seek medical help for afflictions which are Company, Cleveland, Ohio, 1,405 pp. MILLONIG, C. 1976. Laboratory manual of biolog- not life-threatening. ical electron microscopy, M. Saviolo (ed). M. We kindly acknowledge Mrs. G. Van Saviolo (publisher) Vercelli, Italy, 13 pp.

Heube for her excellent technical assistance OSTERHAUS, A. D. M. E., H. W. J. BROEDERS, I. K. SHORT COMMUNICA11ONS 113

C. VI5SER, J. S. TEPPEMA, AND E. J. VEDDER. WILSON, T. M., AND I. POGLAYEN-NEUWALL. 1971. 1990. Isolation of an orthopoxvirus from pox- Pox in South American sea lions (Otaria byronia). like lesions of a grey seal (Halichoerus grypus). Canadian Journal of Comparative Medicine 35: The Veterinary Record 127: 91-92. 174-177. READ, A. J., K. VAN WAEREBEEK, J. C. REYES, J. S. N. F. CHEvILLE, AND L. KARSTAD. 1969. MCKINNON, AND L. C. LEHMAN. 1988. The Sealpox. Bulletin of the Wildlife Disease Asso- exploitation of small cetaceans in coastal Peru. ciation 5: 412-418. Biological Conservation 46: 53-70. H. W. DYKES, AND K. S. T5AI. 1972. Pox VAN WAEREBEEK, K., AND J. C. REYES. 1990. Catch in young, captive harbor seals. Journal of the of small cetaceans at Pucusana port, central Peru, American Veterinary Medical Association 15: during 1987. Biological Conservation 51: 15-22. 611-617. A. J. READ, AND J. S. MCKINNON. WONNACOTT, T. H., AND H. J. WONNACOTT. 1990. 1990. Preliminary observations of bottlenose Introductory statistics, 5th ed. John Wiley and dolphins from the Pacific coast of . Sons, New York, New York, 207 pp. In The , S. Leatherwood and H. Reeves (eds.). Academic Press, San Diego, Cal- Received for publication 13 November 1991. ifornia, pp. 143-154.