How the PRRS virus attacks pigs

The porcine alveolar macrophage is one of the most important means by which a pig clears pathogens from its lungs. Unfortunately, it is also the primary target cell of the PRRS virus, which destroys the macrophage during replication. 

PRRS virus will quickly eliminate around half of all the pig’s alveolar macrophages1; and although these later regenerate, it seems the immune system is already compromised...

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