TY - CPAPER AU - Jeff Zimmerman TI - What We Know About Persistent Infection with Respect to the Epidemiology of PRRS Virus T2 - AASV Annual Meeting DP - American Association of Swine Veterinarians DB - AASV Swine Information Library UR - https://www.aasv.org/library/swineinfo/ PY - 1999 DA - 1999/03/02 L1 - https://www.aasv.org/library/swineinfo/Content/AASV/1999/311.PDF ER -