Laboratory tests have identified that some of the pigs had porcine circovirus, a common disease that affects pigs but does not affect humans.

BBC: China pulls nearly 6,000 dead pigs from Shanghai river

Authorities said one test detected a pig-borne disease in the river called porcine circovirus, but that doesn't normally affect humans, according to the U.S. Centers for Disease Control and Prevention.

WSJ: Floating, Dead Pigs Repulse Shanghai

Although the committee did not issue any formal recommendations, members widely acknowledged that the benefits of vaccinating infants worldwide against rotavirus disease clearly outweigh the theoretical risks associated with the presence of porcine circovirus type 1 (PCV-1) in the vaccines.

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