Laboratory Science Vol 47, No 5 Copyright 1997 October 1997 by the American Association for Laboratory Animal Science

Viral Infections of Nonhuman

Seymour S. Kalter,* Richard L. Heberling, Anthony W. Cooke, John D. Barry, Pei Y. Tian, and William J. Northam

Abstract Approximately 53,000 serologic tests and viral isolation studies were performed on 1,700 nonhu- man specimens for evidence of past and/or current viral infection. Information, other than the re- quested test, generally was not provided with the specimen. This lack of information does not permit any attempt at interpretation of results. Requested testing included a large number of diverse viral agents in approximately 40 primate species. The resulting data are in keeping with those of previous studies and offer an insight into the needs of colony management, as well as some general information on the overall frequency of infection with the indicated viruses. Inasmuch as the results represent testing of single specimens, they are not to be construed as “diagnostic,” and simply indicate past infection as represented by the presence of antibody in the test animal. Viral isolation results are listed, and the number of positive results versus the number of tested emphasizes the limitations of the procedure. Investigations such as these continue to assist in the maintenance of healthy nonhuman primate colonies. This information also supports contin- ued use of nonhuman primates for research in human viral infections and may be helpful in terms of animal selection for use in xenotransplants.

Continued study of nonhuman primates has clearly in- than the requested test(s), clinical or other information did dicated that these animals have a microflora not only of not accompany each specimen. This lack of additional in- unique agents, but of human and other animal or- formation prohibited any correlation of data: health stud- ganisms as well (1–5). Although many organisms appear ies, environment, origin, or age. to be highly specific for their primate hosts, others are able to induce infection or disease in widely diverse animal spe- Materials and Methods cies. In certain instances, the same organism (e.g., measles Specimens were submitted to our laboratory for serologic virus) is capable of infecting human and nonhuman pri- detection of antibody and/or for the isolation of an agent mates. Human infection and the infection of other animals from one or another body specimen. At the time of this study, (zoonoses) are major concerns associated with nonhuman presence of an infective agent was determined by use of primates. Prevention of colony disease outbreaks requires standard isolation procedures (4). All specimens were un- periodic monitoring as well as recognition of clinical infec- solicited, and only the requested tests were performed. In tion within the colony to maintain colony health and con- a number of instances, consultation with the investigator trol possible spread to human and other nonhuman pri- suggested a particular test course to follow, but in general, mates (6). Individuals responsible for such endeavors rou- all tests were those selected by the investigator. Most tinely survey their colonies, including personnel, for the samples for serologic testing were received unfrozen the presence or absence of infective agents. day after acquisition and were placed on test the day of We present an overview of test results obtained at our arrival in the laboratory. Serum samples from outside the laboratory in accordance with requests by individuals in- United States, also unfrozen, generally were received volved with nonhuman primates (e.g., from primate cen- within 2 to 3 days of acquisition. Specimens for virus isola- ters, zoos, biomedical research laboratories, importers, and tion studies, regardless of organ source, also were usually veterinarians with pet-owner clients). In this study, ap- unfrozen on receipt, but ice packs (-20 ) were included in proximately 53,000 tests on sera obtained from approxi- the package. Most specimens for isolation studies were re- mately 40 nonhuman primate species during a selected ceived in an acceptable transport medium within 24 to 48 period in 1994 were performed along with miscellaneous h of acquisition. If a delay in sending specimens for insola- testing of 475 human sera. In addition, 1,700 specimens tion studies was anticipated, it was recommended that the were submitted for virus isolation studies during this same specimens be shipped on dry ice. Delays due to Customs or time. Unfortunately, many of the specimens for isolation other contingencies were infrequent. studies were not collated with the serum samples, thus not In developing these data, the year 1994 was chosen to allowing any diagnostic interpretation. In general, other provide sufficient numbers of test results from a wide as- sortment of nonhuman primate species. In certain in- Virus Reference Laboratory, Inc. (VRL), San Antonio, Texas stances, a small number of additional randomized sera from *Address correspondence to Dr. S. S. Kalter, Virus Reference Labora- tory, Inc. (VRL), 7540 Louis Pasteur, San Antonio, TX 78229. another time interval were tested for those infrequently

461 Vol 47, No 5 Laboratory Animal Science October 1997 used species to provide meaningful numbers. Because the In other instances, a positive serum from a different spe- number of tests requested for each serum sample varied cies was used when it was known that a virus did not in- from one to several, the precise number of tests per animal fect a particular species (e.g., hepatitis B in ). is not indicated. Specimens were submitted from the fol- The following assay methods were used with the indi- lowing species. cated antigens. Apes: Chimpanzee (Pan troglodytes, P. paniscus); gorilla (i) Dot immunobinding assay (7, 8). Herpesvirus (Gorilla gorilla); orangutan (Pongo pygmaeus); gibbon simiae (B virus); Herpesvirus hominis type 1 (HSV-1) and (Hylobates lar, type species); siamang (Symphalangus type 2 (HSV-2); African herpesvirus (SA8); syndactylus). Herpesvirus tamarinus; Herpesvirus saimiri; simian vari- Old World monkeys: (Papio cynocephalus, in- cella (Delta herpesvirus); human varicella-zoster (V-Z) vi- cluding P. anubis, P. papio, P. ursinus, P. hamadryus); colo- rus; rhesus cytomegalovirus (rhCMV); SA6 (African green bus (Colobus polykomos, C. guerezas); guenon (Cercopith- monkey CMV); chimpanzee CMV; squirrel monkey CMV; ecus pygerythrus [vervet], C. sabaeus [African green], C. simian retroviruses (SRV 1–5); Simian T-cell leukemia vi- aethiops [], C. diana [Diana], C. albogularis [Sykes], rus (STLV-1); simian immunodeficiency viruses (SIV); C. mona [Mona], C. neglectus [De Brazza’s], C. nictitans measles (rubeola); rubella; mumps; adenovirus (adenovi- [spot-nose guenon]); (the most frequently submit- rus group-specific antibody); influenza A and B (Influ A and ted test serum, Macaca fascicularis or M. irus [cynomol- B); parainfluenza types 1 to 3 (Paraflu 1–3); respiratory gus], M. mulatta [rhesus], M. nemestrina [pig-tail], M. syncytial virus (RSV); SV40; encephalomyocarditis virus speciosa [stump-tail], M. fuscata [Japanese or snow mon- (EMC); monkeypox; simian hemorrhagic fever (SHF); key], M. silenus [lion tail]); ( sphinx, filoviruses (Ebola-Reston and Marburg); foamyvirus (group- M. leucophaeus); mangabey (Cercocebus atys [sooty specific antibody); rabies; rotavirus (SA11). mangebey], C. torquatus); patas (Erythrocebus patas); pro- (ii) Commercial antibody assay kits (EIA). Hepati- boscis (Nasalis larvatus). tis A (Hep A); total antibody (Abbott HAVAB); Hep A IgM New World monkeys: Capuchin (Cebus capucinus, C. antibody (Abbott HAVAB-M); hepatitis B surface antibody albifrons, C. nigrivitattus, C. apella); howler (Alouatta (HBsAb, Abbott AUSAB); hepatitis B surface antigen belzebul); owl (Aotus trivirgatus); spider (Ateles paniscus, (HBsAg, Abbott AUSZYME); hepatitis B core antibody A. geoffroyi, A. fusciceps, A. belzebuth); squirrel (Saimiri (HBcAb, Abbott CORZYME); hepatitis B Delta antibody sciureus, S. oerstedii); titi (Callicebus personatus); woolly (Hep Delta, Abbott Anti-DELTA); hepatitis C antibody (Hep (Lagothrix lagothricha). C, Abbott HCV 2.0). Serologic testing: Sera were not treated prior to test- (iii) Commercial antibody assay kits (IFA). ing, but were diluted either 1:5 (monkeys) or 1:10 (apes) in Epstein-Barr virus (Gull Laboratories, Salt Lake City, phosphate-buffered saline (pH 7.4). When titer was desired, Utah, EBV-IgG); human herpesvirus type 6 (Advanced sera were serially diluted twofold. Titers are not provided Biotechnologies, Inc., Bethesda, Md., HHV6 IgG IFA); herein, but results are indicated as positive or negative. lymphocytic choriomeningitis (LCM; slides for IFA test- With the exception of hepatitis testing, results were ob- ing were prepared in house, using LCM strain tained by use of dot-immunobinding assay, a modified en- Armstrong-infected Vero E6 cells). zyme immunoassay (EIA) developed in this laboratory (7, Most sera were tested by use of panels of up to five viral 8). Hepatitis testing was performed according to insert di- antigens in the dot immunobinding assay format. rections accompanying manufacturer’s (Abbott Laborato- Virus isolations: Swab specimens submitted for isola- ries, Abbott Park, Ill.) test kits. Immunofluorescent anti- tion studies were placed in approximately 3 ml of cell cul- body (IFA) assays and serum neutralization (SN) tests were ture fluid, vigorously shaken (vortex mixer), and inoculated performed according to manufacturer’s inserts or by use of onto various cell systems (Vero, MRC5, A549, human fore- well-established procedures (4). Appropriate positive- and skin fibroblasts, MA104), depending on the species of pri- negative-control sera were included in all test assays (7). mate under study or the suspected virus. Fecal material Panel testing was requested in most instances, or spe- was triturated into a 10% suspension, then was centrifuged cific recommendations were made if solicited (6). Single at 900 X g for 15 min, and the supernate inoculated onto tests were infrequent and generally reflected an the desired cell systems. Organ specimens were minced investigator’s needs. with scissors until approximately 1-mm3 pieces were ob- The high degree of cross-reactivity between human and tained, and several tissue pieces were then inoculated onto nonhuman primate species immunoglobulins permitted use the cell cultures. Cultures were inspected daily for cyto- of anti-human immunoglobulin conjugates (alkaline phos- pathic effect, then kept 1 to 4 weeks, depending on the sus- phatase, fluorescein isothiocyanate) in performing antibody pected infective agent, before being considered to have nega- assays on monkey and ape sera. Positive- and negative- tive results. Isolates were identified as to virus group by control sera were obtained from our repository of nonhu- hematoxylin and eosin staining of infected cells, and the man primate sera, which has been collected over the past type of viral inclusion formed was determined (9). Specific 20 years and contains a wide range of primate species that viral serotypes were identified by use of the SN test or the have been tested by various means in the past. In some IFA assay, using specific positive sera previously prepared instances, sera from a related species were used (e.g., rhesus by the WHO Collaborating Center for Reference and Re- or cynomolgus serum for testing other macaque species). search in Simian Viruses (4). Isolation results were reported

462 Viral Infections of Nonhuman Primates independently of the serologic data. There is no clearly de- limited number of sera examined, nor was retrovirus anti- fined turn-around time for virus isolation studies. body observed (Table 1). The requests included testing for a large number of di- Monkeys: Sera from three major groups of macaques verse viral agents and specimens, usually serum, from a were submitted: cynomolgus, rhesus, or listed as “macaque” number of different primate species, some identified and (Table 2). Other macaques (Table 3) and Old World mon- others unidentified and listed only as “monkey,” “primate,” keys (Table 4) also were tested. or “macaque.” As expected, many of the macaques were herpes B virus positive. In terms of the 9,091 macaque sera submitted for Results B virus antibody determination, 1,250 (13.7%) seropositives Serologic tests is a relatively small number, compared with previous re- Apes: Chimpanzees and gorillas provide the best insight ports of 80 to 90% infectivity (4, 10), and probably reflects into ape infections and susceptibilities. Information on or- a selective need for colony management to breed seronega- angutans and gibbons (including siamangs) is more lim- tive animals. Sera from this group of macaques did not ited. The gorilla and the chimpanzee frequent Africa, gen- knowingly include those from animals associated with bites, erally below the equator. Orangutans and gibbons are com- scratches, or human exposure. Such animals and sera from mon to Asia; orangutans are found in Borneo and Sumatra, their human counterparts were maintained as a separate and gibbons and siamangs reside in southeast Asia. The program. Greater percentages of seropositives were found data suggest that this geographic distribution has some for other herpesviruses (CMV, EBV), measles virus, Hep A effect on the infection pattern, but further study is needed. virus, SRV, foamyviruses, SV40, and SA11. Respiratory Because the number of siamang sera was small, and the tract virus antibody was not present, generally, although test results were similar to those obtained for gibbons, these parainfluenza 2 virus antibody was detected in sera from data were incorporated with those of the gibbons (Table 1). cynomolgus monkeys. The rhesus group of monkeys had a Herpesvirus infections are common to all apes. More sizable number of positive results for the adenoviruses. chimpanzees and gorillas were seropositive to human HSV- Although results were fewer in number, B virus and 1, HSV-2, and V-Z virus than were orangutans and gib- measles virus antibodies were common in the Japanese, bons. The CMV and EBV infections are universal. Several lion tail, pig-tail, and stump-tail macaque sera (Table 3). SA8 and one B virus seropositive results were obtained. Antibody to SRV was found in the pig-tail and stump-tail Antibodies to the respiratory tract viruses, parainfluenza macaques. The few sera from lion tail macaques contained viruses 1-3, RSV, and measles virus were rather common. Hep A virus and EBV antibodies. Influenza virus antibody was infrequent, but seropositiv- Antibodies to B virus, measles virus, CMV, EBV, and Hep ity was detected. Because of the frequent use of measles A virus were found in the langurs, douc langurs, and pro- vaccine, it is difficult to differentiate “natural” antibody boscis group. Of the African monkeys, and gue- from that in response to vaccination. Hepatitis A and B nons were the most numerous examined. Some data on antibodies were most frequently observed in chimpanzees, colobus monkeys, , and sooty mangabeys were although there was evidence of antibody in other apes. obtained. The baboons were rarely differentiated into the Hepatitis B Delta or C antibodies were not detected in the five recognized species. Accordingly, the data are listed

Table 1. Serologic test results for apes

Virus Chimpanzee Gorilla Orangutan Gibbona

HSV-1 13/56 (23%) 39/63 (62%) 4/36 (11%) 7/39(18%) HSV-2 6/51 (12%) 13/62 (21%) 1/34 (3%) 0/22(0%) SA8 2/56 (4%) 2/61 (3%) 0/33 (0%) 0/19 (0%) B virus 0/10 (0%) 1/8 (13%) 0/5 (0%) 0/16 (0%) Chimpanzee CMV 54/70 (77%) 47/66 (71%) 25/34 (74%) 22/36 (61%) EBV 47/47 (100%) 57/60 (95%) 28/35 (80%) 20/30 (67%) V-Z 21/50 (42%) 32/63 (51%) 4/32 (13%) 5/33 (15%) Para-1 29/57 (51%) 55/85 (65%) 5/48 (10%) 5/21 (24%) Para-2 9/57 (16%) 42/85 (47%) 3/48 (6%) 1/21 (5%) Para-3 43/57 (75%) 73/85 (86%) 10/48 (21%) 8/21 (38%) Measles 34/282 (12%) 50/85 (59%) 31/50 (62%) 8/43 (19%) RSV 27/276 (10%) 27/83 (33%) 12/48 (25%) 6/21 (29%) Hep A (Total) 20/30 (67%) 6/18 (33%) 3/11 (27%) 4/8 (50%) HBsAb 13/42 (31%) 4/22 (18%) 1/18 (6%) 1/10 (10%) HBsAg 4/20 (20%) 1/9 (11%) 0/3 (0%) 1/7 (14%) HBcAb 6/10 (60%) 0/8 (0%) 1/5 (20%) ND Influ A 2/57 (6%) 1/83 (1%) 2/38 (5%) 2/21 (10%) Influ B 1/57 (2%) 1/83 (1%) 0/38 (0%) 2/21 (10%) Retrovirus 0/41 (0%) 0/30 (0%) 0/21 (0%) 0/6 (0%) aIncludes siamang (Symphalangus syndactylus) data. ND = not done. 463 Vol 47, No 5 Laboratory Animal Science October 1997

Table 2. Serologic test results for macaques Table 3. Serologic test results for specific macaque species Virus Cynomolgus Macaque Rhesus Virus Japanese Lion tail Pig-tail Stump-tail B virus 762/2763 (28%) 261/2837 (9%) 204/3321 (6%) B virus 5/30 (17%) 2/60 (3%) 6/61 (10%) 15/19 (79%) HSV-1 4/2326 (0.2%) 0/1792 (0%) 0/1770(0%) HSV-1 0/9 (0%) 0/56 (0%) 0/27 (0%) 0/19 (0%) HSV-2 0/121 (0%) ND ND HSV-2 ND 0/3 (0%) ND ND HHV-6 4/10 (40%) ND 0/1 (0%) Measles 2/9 (22%) 9/53 (17%) 2/27 (7%) 8/19 (95%) SA8 0/19 (0%) ND 0/4 (0%) SRV Delta herpesvirus 13/93 (14%) ND 0/6 (0%) (1, 2, 5) 0/9 (0%) 0/53 (0%) 0/27 (0%) 1/19 (5%) rhCMV 95/100 (95%) 10/11 (91%) 11/19 (58%) SRV-1 ND ND 4/5 (80%) ND EBV 118/123 (96%) 15/15 (100%) 12/15 (80%) SRV-2 ND ND 4/5 (80%) ND Measles 1602/2201 (73%) 794/1181 (67%) 346/775 (45%) SRV-5 ND ND 2/5 (40%) ND Rubella 0/16 (0%) ND ND SIV 0/4 (0%) 0/53 (0%) 0/34 (0%) 0/19 (0%) Influ A 0/14 (0%) 0/8 (0%) ND STLV-1 ND ND 1/7 (14%) ND Influ B 0/14 (0%) 0/8 (0%) ND Hep A (Total) 0/1 (0%) 3/4 (75%) ND ND Paraflu-1 0/14 (0%) 0/8 (0%) ND Hep A IgM 0/1 (0%) 0/4 (0%) ND ND Paraflu-2 5/14 (36%) 0/8 (0%) ND HBsAb 0/1 (0%) 0/4 (0%) ND ND Paraflu-3 0/14 (0%) 0/8 (0%) ND EBV ND 3/3 (100%) ND ND RSV 0/14 (0%) 0/8 (0%) ND Delta ND 0/3 (0%) ND 0/7 (0%) Hep A (Total) 584/679 (86%) 572/734 (78%) 18/246 (7%) herpesvirus Hep A IgM 16/149 (11%) 3/153 (2%) 0/3 (0%) rhCMV ND 2/3 (67%) ND ND HBsAb 2/77 (3%) 5/167 (3%) 0/26 (0%) ND = not done HBsAg 0/94 (0%) 13/170 (8%) 0/32 (0%) Table 4. Serologic test results for other Old World (Asian) monkeys HBcAb 0/25 (0%) ND ND Hep C ND ND 0/25 (0%) Virus Langur Douc Langur Proboscis Hep B Delta ND ND 0/25 (0%) B virus 8/25 (32%) 0/11 (0%) 4/6 (67%) Adenovirus 1/15 (7%) 0/8 (0%) 50/105 (48%) HSV-1 0/26 (0%) 0/11 (0%) 0/6 (0%) LCM 0/32 (0%) 1/38 (3%) 0/14 (0%) HSV-2 0/8 (0%) 0/2 (0%) ND SV40 ND ND 17/19 (90%) Measles 1/19 (53%) 0/10 (0%) 1/6 (17%) SA 11/ ND ND 12/21 (57%) SRV 0/19 (0%) 0/9 (0%) 0/6 (0%) Marburg 0/23 (0%) 0/151 (0%) ND SIV 0/20 (0%) 0/9(0%) 0/6 (0%) Reston 3/336 (0.9%) 22/456 (5%) 0/26 (0%) Delta herpesvirus 0/7 (0%) 0/2 (0%) ND Monkeypox 0/23 (0%) 0/65 (0%) 0/14 (0%) rhCMV 6/7 (86%) 0/2 (0%) ND Tanapox ND 0/44 (0%) ND EBV 6/7 (86%) 1/2 (50%) ND Rabies 0/1 (0%) 38/147 (29%)a 4/56 (7%)a Hep A (Total) 4/8 (50%) 2/2 (100%) 1/3 (33%) Foamyvirus 12/30 (40%) 2/10 (20%) 10/13 (77%) Hep A IgM 0/7 (0%) 0/1 (0%) 0/1 (0%) SHF ND 0/3 (0%) 0/14 (0%) HBsAb 0/7 (0%) 0/2 (0%) 0/1 (0%) SRV 581/1322 (44%) 628/2438 (26%) 68/758 (9%) ND = not done SRV-1 43/608 (7%) 9/316 (3%) 36/263 (14%) SRV-2 43/227 (19%) 20/641 (3%) 40/255 (16%) saimiri. Squirrel monkey CMV antibody was readily found SIV 0/1343 (0%) 3/2328 (0.1%) 0/1121 (0%) in the squirrel, spider, and capuchin monkeys. Results for STLV-1 61/515 (12%) 46/1346 (3%) 59/385 (15%) the few marmosets that were tested for influenza A and B aVaccination virus antibodies indicated susceptibility to these viruses. ND = not done Virus isolations: Approximately 1,700 specimens were examined for the presence of viruses. In general, these con- under Baboon (Papio cynocephalus); similarly, guenons sisted of tissues collected from suspected organs (liver, lung, include the species commonly referred to as African greens, genitals, brain, bone marrow, lymph nodes, vagina, heart, vervets, , and all of the Cercopithecus. stomach, kidney, urinary bladder, salivary glands, spleen, Large numbers of baboons were test positive for SA6, intestines, penis, tongue), blood, and feces, and cell cul- EBV, SA8 and measles virus; similar to the apes, herpes B tures and swab specimens from the throat, eye, rectum, or virus antibody was rarely found. Among the guenons, SA8, a skin lesion. During this survey period, 145 (8.5%) agents SA6, EBV, Delta herpesvirus, SIV, measles, Hep A, were isolated from the 1,700 specimens examined. foamyvirus, SV40, and adenovirus antibodies were de- The principal isolate from the macaques was SRV (5%, tected. Although the number of sera tested for species in not typed) and foamyviruses (2%). Herpes B virus was the other groups was small, SA8, SA6, measles virus, EBV present (0.7%), but again the small numbers probably re- and Hep A virus antibodies were detected among the vari- flect investigators’ efforts to develop B virus-free colonies ous monkeys tested (Table 5). and agree with the serologic findings. Adenoviruses (0.7%, Among the New World primates, marmoset and squir- different types), enteroviruses, and CMV were isolated on rel, spider, and capuchin monkey sera were the most fre- several occasions (Table 7). quently submitted specimens, with those from the squirrel In those instances in which serum was available and a monkey far exceeding the others (Table 6). A number of virus was isolated from the same animal, correlations were squirrel monkeys had antibodies to H. tamarinus and H. generally impossible. Serum sample and specimen for iso-

464 Viral Infections of Nonhuman Primates

Table 5. Serologic test results for Old World (African) monkeys Virus Baboon Guenons Colobus Mandrill Mangabey Patas SA8 179/311 (58%) 72/625 (12%) 1/35 (3%) 2/11 (18%) 0/16 (0%) 3/13 (23%) B virus 2/225 (0.04%) 0/411 (0%) 0/26 (0%) 0/11 (0%) 0/10 (0%) 0/8 (0%) HSV-1 8/105 (8%) 1/368 (0.3%) 0/16 (0%) 0/2 (0%) 0/10 (0%) 0/11 (0%) HSV-2 0/76 (0%) 0/34 (0%) 0/7 (0%) 0/2 (0%) 0/2 (0%) 0/3 (0%) Measles 35/156 (22%) 5/583 (0.9%) 1/30 (3%) 2/9 (22%) 0/14 (0%) 1/9 (11%) SA6 222/276 (80%) 564/755 (75%) 23/35 (66%) 3/9 (33%) 13/14 (93%) 10/12 (83%) Delta herpesvirus 19/68 (28%) 2/40 (5%) 0/7 (0%) 0/2 (0%) 0/2 (0%) 0/3 (0%) EBV 97/102 (95%) 38/40 (95%) 5/7 (71%) 1/2 (50%) 2/2 (100%) 3/3 (100%) HIV-1 0/18 (0%) 0/9 (0%) ND ND ND 0/3 (0%) HIV-2 0/18 (0%) 0/6 (0%) ND ND ND ND SIV 2/304 (0.7%) 20/870 (2%) 0/48 (0%) 0/7 (0%) 0/15 (0%) 0/9 (0%) SRV 0/15 (0%) ND 0/3 (0%) ND ND ND SRV-1 2/137 (2%) 0/137 (0%) 0/4 (0%) ND ND ND SRV-2 5/110 (5%) 2/137 (2%) 0/4 (0%) ND ND ND SRV-5 2/113 (2%) 0/137 (0%) 0/4 (0%) ND ND ND Hep A (Total) 12/69 (17%) 2/6 (33%) 0/3 (0%) ND 2/4 (50%) 0/1 (0%) HBsAb 1/44 (2%) 0/2 (0%) 0/3 (0%) 0/2 (0%) 0/4 (0%) ND HBsAg 0/26 (0%) 0/3 (0%) ND 0/2 (0%) 0/2 (0%) ND Hep C 0/15 (0%) ND ND 0/2 (0%) 0/2 (0%) ND LCM 0/78(0%) ND ND ND ND ND Monkeypox 0/79 (0%) ND ND ND ND ND SHF 0/167 (0%) ND ND ND ND 0/2 (0%) Marburg 0/83 (0%) 3/103 (3%) ND ND ND ND Filovirus 0/3 (0%) 0/103 (0%) ND ND ND ND Foamyvirus 69/89 (78%) 127/279 (46%) ND ND ND ND Rabies 0/21 (0%) ND ND ND ND ND Paraflu-2 0/5 (0%) ND ND ND ND ND SV-5 0/5 (0%) ND ND ND ND ND SV40 8/24 (33%) 5/123 (4%) ND ND ND ND Adenovirus 10/12 (83%) ND 1/1 (100%) ND ND ND SA11 12/20 (60%) ND ND ND ND ND EMC 0/74 (0%) ND ND ND ND ND RSV ND ND 0/5 (0%) ND ND ND ND = not done lation had been collected during the acute stages of the continue to be a problem in colony management. Some of infection prior to development of antibody. Rarely were these infections are of minimal importance; others may convalescent sera submitted from those individuals. In be devastating, with maximal losses and concern over those instances in which a convalescent specimen was possible human involvement. As expected, macaques (cy- obtained, increased titer to the isolate was detected in nomolgus and rhesus) provided most of the test speci- that specimen. mens. Other species also were tested in sufficient num- Human studies: During the tenure of this study, 475 bers to yield an insight into their past infections or sus- human sera were received from individuals bitten, ceptibility to viruses. scratched, or sufficiently exposed to macaques to request The lack of details provided with the unsolicited speci- screening for possible herpes B virus infection. Gener- mens makes it impossible to draw any conclusions regard- ally, specimens (for serologic testing and/or virus isola- ing clinical significance or incidence of virus infections in a tion attempts) from the responsible animals also were primate species. In most instances, the status of the colony tested to determine their B virus status. Of the humans, being tested was not indicated. Numerous viral serologic one individual was found to be herpes B virus seroposi- tests were requested for a large group of sera obtained from tive; however, no specimens were obtained from the mon- approximately 40 species of nonhuman primates and from key. Those humans bitten or scratched by B virus sero- 475 humans. Independently, 1,700 specimens were provided positive monkeys did not develop infection or antibody. for virus isolation studies. If a relationship existed between the animals from whom serum and isolation material was Discussion obtained, this information was generally not indicated. This Nonhuman primates continue to be the experimental report, therefore, provides only the serologic and isolation animals of choice for the study of many human diseases. data for specimens collected from an extensive group of Infectious disease outbreaks of known and unknown causes primates without any attempts at interpretation of results.

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Table 6. Serologic test results for New World monkeys Virus Squirrel Spider Capuchin Marmoset H. tamarinus 51/268 (19%) 1/29 (3%) 2/48 (4%) 0/38 (0%) H. saimiri 59/268 (22%) 2/29 (7%) 0/48 (0%) 0/37 (0%) Measles 1/82 (1%) 2/29 (7%) 3/47 (6%) 2/43 (5%) Sq. Mk. CMV 147/254 (58%) 15/29 (52%) 22/47 (47%) 0/37 (0%) Influ A ND ND ND 4/12 (33%) Virus Owl Woolly Howler Saki Titi Adenovirus 7/8 (78%) ND ND ND ND EBV 1/9 (11%) 5/5 (100%) ND ND ND Measles ND 2/9 (22%) 1/14 (7%) ND ND Sq. Mk. CMV ND ND 3/15 (20%) ND ND HBsAb ND ND 1/8 (13%) ND ND Hep. A (Total) ND ND ND 2/2 (100%) 0/18 (0%) Sq. Mk. = squirrel monkey ND = not done not represent true Ebola-Reston virus antibody, but rather Table 7. Virus isolations and their sources nonspecific or cross reactions with a still unrecognized Virus No. of Isolations Source Species filovirus (11, 12). Testing for infections in apes, including Adenovirus 11 Feces Baboon hepatitis A, B, C, and D viruses, is used to determine threats Pharynx Rhesus to human contacts (13) and status prior to shipment be- Rectum tween zoos for breeding purposes. Retroviruses received a a Isolates great deal of attention for purposes of establishment of clean Feces “Macaque” SRV 52 Lymph node Cynomolgus colonies, diagnosis of clinical infections, and use of baboons Spleen as donors for xenotransplants. Rabies occurs in nonhuman Blood primates, but the indicated positive antibody results re- Tissue flect vaccinations (4). Penis Human herpes simplex infectivity is a common feature 27 Blood Rhesus 3 Blood “Macaque” among apes and may reflect human contact. Infection of Serum apes with HSV-1 and HSV-2, or viruses closely related to Lung these strains, is frequently detected (14). Antibodies to HSV- 6 Blood “Monkey” 1 and HSV-2 in African and Asian monkeys are rarely de- B virus 1 Kidney Cynomolgus tected and have been attributed to experimentally induced 5 Eye swab Rhesus Tongue infections or inoculation with human immune globulins to Spleen prevent measles in newly imported animals on several oc- Serum casions (unpublished data). Apparently B virus and SA8 B virus 6 Swabb “Macaque” are highly selective for Asian and African monkeys, respec- Liver tively (Tables 2–4). Varicella-zoster is infrequently seen in Tissueb Spleen the orangutan and the gibbon, in contrast to chimpanzees. Swab (oral) “Monkey” Differences in population density in Asia, compared with Foamyvirus 25 Pharynx Rhesus Africa, may support the observed differences in findings; Rectum however, human contact with animals in captivity may also Bladder explain the observed results. Urine SV11 3 Tissueb Rhesus Extensive divergence in virus infections exists between Enterovirusc 1 Swabb the Old and New World monkeys. To some extent, this is CMV 3 Kidney cell culture Vervet also true of the Asian and African nonhuman primates, HSV-2 1 Swabb Chimpanzee particularly for herpes B virus in Macaca spp. It remains Herpesvirus 1 Liver Langur to be seen whether B virus isolates from different macaque aIsolates submitted for identification species have different pathogenic potentials for humans. A bSpecific source not identified recent polymerase chain reaction study of rhesus and cy- cEnterovirus not typed nomolgus B virus isolates indicates that there are genetic differences between the two, although the significance for Recent events in primate colonies caused investigators the biological properties of these isolates remains to be to consider increased laboratory testing, some of it man- determined (15). Other type-A herpesviruses are found in dated by the Centers for Disease Control and Prevention. a variety of African monkeys and apes; although these are As an example, the recent Ebola-Reston outbreak resulted antigenically related, they are distinct from B virus. Simi- in a belated upsurge of testing for this virus (6/960, 0.6%). larly, a diversity of herpesviruses is present in New World The few seropositives without fatality suggest these may monkeys; these are not only antigenically distinct from the

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Old World monkey herpesviruses, but from each other as 2. Kalter, S. S., and R. L. Heberling. 1971. Comparative vi- well. rology of primates. Bacteriol. Rev. 35:310–364. 3. Kalter, S. S., and R. L. Heberling. 1976. Health hazards The major consideration of those involved with nonhu- associated with newly imported primates and how to avoid man primates, macaques in particular, is human infection them, p. 5–21. In D. J. Chivers and E. H. R. Ford (ed.), Recent with herpes B virus. Availability of therapy has reduced advances in primatology, vol. 4. Medicine; Proceedings of the mortality, but the possible need for lifelong treatment, along Sixth Congress of the International Primatological Society, with side effects, makes treatment an unpleasant prospect. Cambridge, England. Academic Press, Inc., London. 4. Kalter, S. S. 1986. Overview of simian viruses and recog- The possibility of infection with other monkey-borne agents nized virus diseases and laboratory support for the viral di- also is a source of anxiety. Breeding of B virus-free agnosis of viral infections, p. 681–709. In K. Benirschke (ed.), macaques is now a well-established procedure. This selec- Primates. The road to self-sustaining populations. Springer- tive breeding has reduced the presence of B virus in Verlag, N.Y. 5. Brack, M. 1987. Agents transmissible from to man, macaque colonies. Finding only 13.7% herpes B virus p. 1–454. Springer-Verlag, N.Y. seropositives may represent sample bias, but this is a 6. Kalter, S. S., and R. L. Heberling. 1990. Viral battery test- marked difference from previous reports of 80 to 90% colony ing in nonhuman primate colony management. Lab. Anim. infectivity (10). Where the information has been made avail- Sci. 40:21–23. able, it is clear the B virus-free colonies can be established. 7. Heberling, R. L., and S. S. Kalter. 1986. A rapid dot- immunobinding assay on nitrocellulose for viral antibodies. Incidental to this study, but a necessary ancillary com- J. Clin. Microbiol. 23:109–113. ponent, was the testing of humans exposed to macaques. 8. Heberling, R. L., and S. S. Kalter. 1987. A dot- In keeping with the recognized status of B virus infection, immunobinding assay (DIA) on nitrocellulose with psoralen 1 of 475 human sera was seropositive. In large part, these inactivated Herpesvirus simiae (B virus). Lab. Anim. Sci. 37:304–308. sera were collected at the time of trauma before antibody 9. Malherbe, H. M., and M. Strickland-Cholmley. 1980. Vi- could develop, which is a possible explanation for the high ral cytopathology, p. 1–78. CRC Press, Inc., Boca Raton, Fla. seronegativity rate. 10. Benirschke, K. (ed.). 1986. Primates. The road to self-sus- Isolation results typify the difficulties in obtaining an taining populations, p. 1–1044. Springer-Verlag, N.Y. agent from the materials provided. Time of infection/dis- 11. Kalter, S. S., R. L. Heberling, J. D. Barry, et al. 1995. Detection of Ebola-Reston (Filoviridae) virus antibody by dot- ease before specimen acquisition, handling, appropriate- immunobinding assay. Lab. Anim. Sci. 45:523–525. ness of specimens, and choice of laboratory procedures in- 12. Centers for Disease Control. 1990. Update: filovirus in- fluence the outcome. The results reported herein are in fections among persons with occupational exposure to nonhu- keeping with expected isolation findings (4). man primates. MMWR Morb. Mortal. Wkly. Rep. 39:266–267. 13. Hillis, W. D. 1961. An outbreak of infectious hepatitis among This study is also of interest in view of the recent con- chimpanzee handlers at a United States air force base. Am. cern with regard to the use of primates for xenotransplants J. Hyg. 73:316–328. and points out the need to thoroughly test potential donor 14. McClure, H. M., R. B. Swenson, S. S. Kalter, et al. 1980. animals for the presence of viruses that may harm the re- Natural genital Herpesvirus hominis infection in chimpan- cipient. zees (Pan troglodytes and Pan paniscus). Lab. Anim. Sci. 30:895–901. 15. Slmoka, M. J., D. W. G. Brown, J. P. Clewley, et al. 1993. Polymerase chain reaction for detection of herpesvirus simiae References (B virus) in clinical specimens. Arch. Virol. 131:89–99. 1. Kalter, S. S., J. Ratner, G. V. Kalter, et al. 1967. A survey of primate sera for antibodies to viruses of human and simian origin. Am. J. Epidemiol. 86:552–568.

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