Molecular Surveillance for Lymphoproliferative Disease Virus and Reticuloendotheliosis Virus in Rio Grande Wild Turkeys (Meleagris gallopavo intermedia) in Texas, USA.

Reticuloendotheliosis virus (REV) and lymphoproliferative disease virus (LPDV) are avian retroviruses that can cause neoplastic disease and present with similar pathologies. Lymphoproliferative disease virus has been reported in the Eastern US and states bordering Texas, USA, but has not been previously detected within the state. In a prior study, we detected REV in native Rio Grande Wild Turkeys (Meleagris gallopavo intermedia) and an Eastern Wild Turkey (Meleagris gallopavo silvestris) originating from West Virginia. Given LPDV detection in states bordering Texas and our finding of an REV-positive Eastern Wild Turkey imported from a LPDV endemic region, we sought to determine LPDV prevalence in Texas and continue surveillance for REV. During 2018-20, dried blood spots from 373 individual Rio Grande Wild Turkeys from 20 different counties were tested for the presence of proviral REV or LPDV DNA. In affected counties, approximately 4% of individuals were infected with REV (7/197) or LPDV (10/273) and one bird was coinfected with both viruses. Phylogenetic analysis indicated a close relationship of the LPDV isolates to variants from other Southern and Central states. This study provides molecular evidence of LPDV in Texas, and continued surveillance is necessary to determine the potential effects of the virus on reproductive success, coinfections, and overall health of Wild Turkey populations.

Genome Sequence of Fowlpox Virus-Integrated Reticuloendotheliosis Virus from a Rio Grande Wild Turkey (Meleagris gallopavo intermedia).

We report the genome sequence of a nearly intact reticuloendotheliosis virus (REV) insertion within a field strain of fowlpox virus from a Rio Grande wild turkey in Gillespie County, TX. The proviral REV genome comprises 7,943 bp and contains partial long terminal repeats.

Survey of Reticuloendotheliosis Virus in Wild Turkeys (Meleagris gallopavo) in Texas, USA.

Reticuloendotheliosis virus (REV) is an immunosuppressive and sometimes oncogenic avian retrovirus that establishes lifelong infection in a wide range of avian species. REV-infected wild birds roaming near at-risk captive flocks, such as is the case for the highly endangered Attwater's Prairie Chicken (APC; Tympanuchus cupido attwateri), could act as a reservoir for viral transmission. In wild birds, prevalence rates of REV are low and appearance of associated disease is uncommon. During 2016-17, nearly half of all captive adult APC mortality at Fossil Rim Wildlife Center captive breeding facility in Glen Rose, Texas, US was attributed to REV infection. The unusually high REV prevalence rate prompted us to survey for this virus in wild galliforms throughout the region. From 2016-17, 393 blood samples collected from two subspecies of Wild Turkeys (Meleagris gallopavo) were tested for REV proviral DNA through amplification of the viral 3' long terminal repeat and segments of the viral pol gene. In REV-affected counties, 5% (5/98) of native Rio Grande Wild Turkeys (Meleagris gallopavo intermedia) were identified as REV-positive. In addition, we detected REV in one of 62 Eastern Wild Turkeys (Meleagris gallopavo silvestris) that had been imported during conservation efforts. To better determine protective measures, continued surveillance, including collection and genetic analysis of REV-infected samples, is necessary to identify sources of REV outbreaks in captive APC flocks.