Six macaques were tested for herpes B; four (67) were seropositive. B-virus infection is transmitted among free-ranging or group-housed animals, primarily through sexual activity and bites. The high percentage of death in known cases of human B-virus disease underscores the potential seriousness of all bite or scratch exposures from macaques. B virus is also commonly referred to as herpes B, monkey B virus, herpesvirus simiae, and herpesvirus B. However, infection in macaques can only be transmitted during active viral shedding through body fluids. Most macaques carry B virus without overt signs of disease. However, zoonotic infection with B virus in humans usually results in fatal encephalomyelitis or severe neurologic impairment. The viral genome is G+C rich (75 G+C), the highest of any known herpesvirus (4). Excretion of B virus in monkeys and evidence of genital infection.
The B virus in monkeys does not sicken the monkeys but when passed to humans leads to deadly infections of the brain. About 80 percent to 90 percent of adult rhesus macaques are infected with the herpes B virus. Macaques are about 18 to 24 inches high, weigh up to 40 pounds. Types of macaque monkeys known to carry herpes B are Tibetan macaques, lion-tailed macaques and crab-eating macaques. Notably, mutants resistant to high levels of these drugs occur spontaneously in tissue culture. Untreated B virus infections in humans result in an extremely high mortality rate ( 80 ) and, consequently, present unique and potentially lethal challenges for individuals handling macaque monkeys or macaque cells and tissues. B virus polypeptides/glycoproteins can be grouped into classes that differ in their relative rates of synthesis at different times throughout the virus replication cycle, as is characteristic of alpha herpesviruses. Post mortem vitreous cultures taken from both eyes and retina have been positive for B virus. Thus, B virus can produce infection and destruction of retinal tissue similar to that of other herpesviruses.
Herpes B virus is an alpha herpesvirus that is particularly enzootic (endemic in animals) in the rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) members of the macaque genus, Macaca (as seen in the image below). Herpes B virus demonstrates a broad host range in tissue culture, producing a lytic infection in cells of humans, nonhuman primates, small mammals, and many birds. Both wild and captive macaque populations generally exhibit high rates of herpes B virus infection, but most individuals exhibit few or no symptoms of infection. Herpes simian B virus (Macacine herpesvirus 1 (formerly Cercopithecine herpesvirus 1, CHV-1 1 ), Herpesvirus simiae, B virus) is the endemic simplexvirus of macaque monkeys. Severity of the disease increases for untreated patients, with a case fatality rate of approximately 80. Each gene-encoded glycoprotein, including gB, gC, gD, gE and gG, has approximately 50 homology with HSV, with a slightly higher predilection towards HSV-2 over HSV-1. Macaques typically carry the B virus throughout their lives and shed it intermittently in saliva or genital secretions. Such protocols can have life-or-death implications, as the herpes B virus has proved fatal in approximately 80 percent of known cases.
Primate Info Net:
15 Herpes B (Herpesvirus simiae) AGENT: DNA Herpesvirus. First reported case of encephalitis caused by B virus in monkey handler was in 1932. The virus is enzootic in rhesus, cyno and other asiatic monkeys of macaque genus. The virus naturally infects macaque monkeys, resulting in disease that is similar to herpes simplex virus infection in humans. B virus (Cercopithecine herpesvirus 1) is a naturally occurring infectious agent that is endemic among macaque monkeys (including rhesus macaques, pig-tailed macaques, cynomolgus monkeys, and other macaques) 1 3. Among untreated humans, the mortality rate associated with B virus infection is estimated to be 80 3. High-dose, prolonged therapy with valacyclovir has also been associated with CNS disturbances in renal transplant recipients 36. The DNA genomes of simian -herpesviruses are high in G+C content. In macaque monkeys, who are the natural host for Herpes B, severe disease resulting from Herpes B infection does not commonly occur. The virus most commonly appears to be transmitted through biting and scratching (6). She caught the virus when a body fluid from a rhesus monkey hit her in the eye on October 29. More than 47,000 nonhuman primates, mostly macaques, were used in research in 1990, and that number is higher today, according to David Davenport, an associate professor of medicine and infectious diseases at the Michigan State University Kalamazoo Center for Medical Studies. Herpes B infects 80 percent to 90 percent of adult macaques, including rhesus and cynomolgus monkeys. She carried the monkey’s cage at arm’s length, which Yerkes officials considered a low-risk activity. Most macaque monkeys carry a disease called simian herpes virus B. According to the U. B-virus infection is highly prevalent (80 percent to 90 percent) in adult macaques and may cause a potentially fatal meningoencephalitis in humans. This results in high rates of mortality and morbidity. B-virus may be fatal in several non-macaque species of monkeys including patas, black and white colobus, capuchin, Debrazza monkeys and common marmosets. It is safest to assume that all macaques are carrying and capable of transmitting Herpes B infection. Because of the high mortality rate from human filovirus infections (Ebola, Marburg-Europoe, Sudan and Zaire strains), the CDC has updated regulations and inspections of imported primates.
Herpes B: Background, Pathophysiology, Epidemiology
The antigenic cross-reactive characteristics of herpes B virus and herpes simplex virus (HSV) type 1 (HSV-1) and HSV-2 are responsible for false-positive diagnoses by serological assays in humans and macaques. Sera collected from humans and rhesus macaques were investigated for the presence of antibodies to the recombinant proteins of the three herpesviruses. It is suggested that the ELISA with the recombinant antigens is useful not only for the serodiagnosis of primate herpesvirus infections but also for elucidation of the seroprevalence of herpesviruses in humans and primates. The rate of mortality among individuals with the infection is high if such individuals are not given antiviral therapy in the early stages of infection. The number is estimated to be quite high. Herpes B-virus: 80 to 90 percent of all macaque monkeys are infected with Herpes B-virus or Simian B, a virus that is harmless to monkeys but often fatal in humans. This past year Gibraltar celebrated (and Spain rued) 300 years of continuous British control of the area while the macaques ambled contentedly over the vegetated, western side of the Rock, high above Gibraltar city and harbor. Monkeys aren’t likely to follow, because 90 percent of the world’s primates live in tropical forests. As part of the Notre Dame study, Fuentes had the macaques tested for the herpes B virus, which macaques are known to carry. Post-Exposure To B Virus From Old World, Macaque Monkeys First Aid Treatment. Corrective action taken to prevent the re-occurrence of the incident. Prophylaxis: Yes, individuals thought to be at high risk for infection following a bite, laceration, or puncture wound when working with infected neural tissue are administered antivirals.
Night has fallen here, and the monkey doctors are having a party. Scientists say the risk of being infected by lethal pathogens carried by the animals is never far from their minds. Herpes B is a monkey virus that coexists peacefully with macaques but is usually fatal on the rare occasions it finds its way to man, generally through monkey bites or scratches. Twenty percent to 60 of the macaques in U.S. primate research centers carry the Herpes B virus.