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Road 98 & Hutchison
CNPRC – UC Davis
Davis, CA 95616

530-752-8249

Simian Retrovirus Type D (SRV)

The exogenous simian type D retroviruses (SRV) are a group of closely related viruses that have been isolated from Asian monkeys. These isolates are related to the prototypic type D retrovirus, Mason-Pfizer monkey virus (MPMV). SRV has been isolated from many macaque species including rhesus, cynomolgus, and pig-tailed monkeys. Although all macaque species appear susceptible to all serotypes, some general serotype-host species associations have been recognized. Cynomolgus and pig-tailed macaques are predominantly infected with serotype 2, while in rhesus SRV-1 is the predominant serotype. Prevalence of SRV infection in captive populations of macaques is variable. Geographic origin of animals, as well as management and husbandry practices, are factors influencing the level of SRV endemicity in macaque populations.

SRV has a broad cellular tropism, including both lymphoid and non-lymphoid tissues. SRV can be demonstrated in many tissues and organs and has been isolated from many body fluids, including saliva, urine, blood, lacrimal secretions, cerebrospinal fluid, and breast milk. Transmission of SRV occurs horizontally, either through direct contact between infected and susceptible animals, or indirectly through contact with contaminated instruments or equipment. A major mode of transmission is via contact with virus shed in saliva , either during mutual grooming or aggressive interactions involving biting and scratching. Transplacental transmission has been documented.

SRV can elicit a broad spectrum of clinical and pathologic manifestations, ranging from subclinical carriers to rapidly fatal immunosuppressive disease. Common clinical findings in SRV-infected macaques include diarrhea, weight loss, splenomegaly, lymphadenopathy, anemia, neutropenia, lymphopenia, and occasional neoplastic disease, including cutaneous fibrosarcoma and retroperitoneal fibromatosis. B-cell lymphomas have been reported in cynomolgus macaques.

A significant number of SRV-infected macaques are seronegative. Parallel testing for both SRV antibody and virus (PCR), at more than one time point, are required to accurately identify all infected animals.

Testing for proviral DNA is available by Taqman real-time PCR which targets the env gene. Quantitation and typing may also be available by arrangement. Please contact us. Antibody screening using at least 2 different SRV purified virus and a recombinant transmembrane antigens in our MMIA is included in our Antibody Screening Panel (AbScn). Confirmatory testing by Western blot prepared with SRV 1,2, or 5 virus is available.