Theoretically, the plaque-forming unit includes only the infectious virus particles since a virus particle failing to infect a host cell will not be able to produce a plaque, hence, will not be counted. PFU rules out possible multiple-hit phenomena and include only the particles capable of infecting cells on their own. Thus, one PFU means one lytic event (or one infectious virus particle).
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... infection. He is currently being monitored at the specialized referral unit in Belem. He does not have any opportunistic infections and is not taking ... of the lesion included an erythematous-infiltrated, hypertrophic plaque with a verrucous surface ≈4 cm long in the distal third of the ...
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