CWD/Prion News

• Board OKs plan for CWD management published on Apr 24, 2008
  Members of the state Natural Resources Board approved a framework for chronic wasting disease (CWD) management during the 2008 deer hunting season today, while stressing that they ultimately want a comprehensive new statewide plan for controlling the fatal nervous system disease.
• High titers of mucosal and systemic anti-PrP antibodies abrogate oral prion infection in mucosal-vaccinated mice published on Apr 22, 2008
  Significant outbreaks of prion disease linked to oral exposure of the prion agent have occurred in animal and human populations. These disorders are associated with a conformational change of a normal protein, PrPC (C for cellular), to a toxic and infectious form, PrPSc (Sc for scrapie). None of the prionoses currently have an effective treatment. Some forms of prion disease are thought to be spread by oral ingestion of PrPSc, such as chronic wasting disease and variant Creutzfeldt-Jakob disease. Attempts to obtain an active immunization in wild-type animals have been hampered by auto-tolerance to PrP and potential toxicity. Previously, we demonstrated that it is possible to overcome tolerance and obtain a specific anti-PrP antibody response by oral inoculation of the PrP protein expressed in an attenuated Salmonella vector. This past study showed that 30% of vaccinated animals were free of disease more than 350 days post-challenge. In the current study we have both optimized the vaccination protocol and divided the vaccinated mice into low and high immune responder groups prior to oral challenge with PrPSc scrapie strain 139A. These methodological refinements led to a significantly improved therapeutic response. 100% of mice with a high mucosal anti-PrP titer immunoglobulin (Ig) A and a high systemic IgG titer, prior to challenge, remained without symptoms of PrP infection at 400 days (log-rank test P0.0001 versus sham controls). The brains from these surviving clinically asymptomatic mice were free of PrPSc infection by Western blot and histological examination. These promising findings suggest that effective mucosal vaccination is a feasible and useful method for overcoming tolerance to PrP and preventing prion infection via an oral rout
• Report: Recreational hunting alone will not control CWD published on Apr 09, 2008
  Report outlining that hunting alone cannot control CWD in WI and that effective CWD management will require dramatic and sustained efforts.
• West Virginia: Four Additional Deer Test Positive for Chronic Wasting Disease In Hampshire County, West Virginia published on Apr 04, 2008
  West Virginia continues efforts to define prevalence and distribution of CWD.
• British Researchers Discover New Variant of CJD published on Apr 01, 2008
  A case of Creutzfeldt-Jakob Disease in Britain changes predictions of future infection rates.
• CWD Update #90 - Bryan J. Richards, USGS National Wildlife Health Center. published on Mar 07, 2008
  Regional and State updates on CWD occurances and news.
• Susceptibility of Cattle to First-passage Intracerebral Inoculation with Chronic Wasting Disease Agent from White-tailed Deer published on Mar 01, 2008
  Fourteen, 3-month-old calves were intracerebrally inoculated with the agent of chronic wasting disease (CWD) from white-tailed deer (CWDwtd) to compare the clinical signs and neuropathologic findings with those of certain other transmissible spongiform encephalopathies (TSE, prion diseases) that have been shown to be experimentally transmissible to cattle (sheep scrapie, CWD of mule deer CWDmd, bovine spongiform encephalopathy BSE, and transmissible mink encephalopathy).