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GuidelinesCopied from CDC web site on 12/7/96
AGENT: Herpesvirus simiae (B-virus)
B-virus is a naturally occurring alphaherpesvirus infecting free-living or captive Macaca mulatta, M. fasicularis, and other members of the genus. It is associated with acute vesicular oral lesions, as well as latent and often recrudescent infection (193). Human infection has been documented in 25 instances, usually with a lethal outcome or serious sequelae from encephaliti (7, 92, 145).
Although B-virus presents a potential hazard to laboratory personnel working with the agent, laboratory-associated human infections with B-virus have, with rare exceptions, been limited to those having direct contact with macaques. Primary macaque cell cultures, including commercially-prepared rhesus monkey kidney cells, occasionally are inapparently infected with B-virus and have been implicated in one human case (92).
Sixteen fatal cases of human infections with B-virus have been reported (193).
LABORATORY HAZARDS: The highest risk of acquiring B-virus from macaques is through the bite of an infected monkey with active lesions. Contamination of broken skin or mucous membranes with oral, ocular, or genital secretions from animals with lesions, or experiencing clinically silent virus shedding, is also dangerous. Stability of viral infectivity on cages and other surfaces is not known, but the potential hazard must be recognized. The importance of aerosol exposure is thought to be minimal. Attenuated or avirulent strains have not been identified.
The agent also may be present in thoracic and abdominal viscera and nervous tissues of naturally infected macaques. These tissues, and the cultures prepared from them, are potential hazards (196).
RECOMMENDED PRECAUTIONS: Biosafety Level 2 practices and facilities are recommended for all activities involving the use or manipulation of tissues, body fluids, and primary tissue culture materials from macaques. Additional practices and personnel precautions, such as those detailed for Biosafety Level 3, are recommended for activities involving the use or manipulation of any material known to contain Herpesvirus simiae. In vitro propagation of the virus for diagnosis may be conducted under the same guidelines, but it would be prudent to confine manipulations of positive cultures which would contain high-titered virus to a Class 3 biosafety cabinet or BSL-4 facility, depending on the judgement of the laboratory director.
Biosafety Level 4 practices and facilities are recommended for activities involving the propagation and manipulation of production quantities or concentrates of H. simiae.
The wearing of gloves, masks, and laboratory coats is recommended for all personnel working with non-human primates -- especially macaques and other Old World species -- and for all persons entering animal rooms where non-human primates are housed. Any macaque colony not known to be free of B-virus infection should be presumed to be naturally infected. Guidelines are available for safely working with macaques and should be consulted (39, 150). Animals with oral lesions suggestive of active B-virus infection should be isolated and handled with extreme caution. Studies with animals experimentally infected with H. simiae should be conducted at ABSL-3.
Vaccines are not available for use in humans. Human to human transmission has only occurred in one case, suggesting that precautions should be taken with vesicle fluids, oral secretions, and conjunctival secretions of infected persons (92).
Antiviral drugs have shown promise in the therapy of rabbits infected with H. simiae, and anecdotal observations suggest this may extend to man (7, 92). Because of the seriousness of infection with this virus, experienced medical personnel should be available for consultation to manage incidents involving exposure to the agent or suspected infections.
REFERENCES
7. Artenstein, A.W., Hicks, C.B., Goodwin, B.S., Hilliard, J.K. 1991. Human Infection with B Virus Following a Needlestick Injury. Rev Infect Dis 13:288-91.
39. Centers for Disease Control. 1987. Guidelines for prevention of Herpesvirus simiae (B virus) infection in monkey handlers. MMWR, 36:680-2,687-9.
92. Holmes, G.P., Hilliard, J.K., Klontz, K.C., Rupert, A.H., Schindler, C.M., Parrish, E., Griffin, D.G., Ward, G.S.,Bernstein, N.D., Bean, T.W., Ball, M.R., Brady, J.A., Wilder, M.H., Kaplan, J.E. 1990. B Virus (Herpesvirus simiae) Infection in Humans: Epidemiologic Investigation of a Cluster. Ann of Int Med 112:833-839.
145. Palmer, A.E. 1987. B Virus, Herpesvirus simiae: historical perspective. J. Med. Primatol 16:99-130.
150 Perkins, F.T., Hartley, E.G. 1966. Precautions against B virus infection. Brit Med J 1:899-901.
193. Weigler, B.J. 1992. Biology of B Virus in Macaque and Human Hosts: A Review. Clin Infect Dis 14:555-67.
196. Wells, D.L., Lipper, S.L., Hilliard, J.K., Stewart, J.A., Holmes, G.P., Herrmann, K.L., Kiley, M.P., Schonberger, L.B. 1989. Herpesvirus simiae Contamination of Primary Rhesus Monkey Kidney Cell Cultures. Centers for Disease Control Recommendations to Minimize Risks to Laboratory Personnel. Diagn Microbiol Infect Dis 12:333-336.