The erroneous practices used during the bubonic plague outbreak in europe to slow the spread of the disease included penicillin injections putting patients in solitary confinement (quarantine) to keep other's from getting sick quarantine the household all together. allow the sick to lay out in sunshine to purify the skin and lungs.

Quarantine the household together is the correct answer.

Explanation:

Organized responses for controlling the diseases began during the epidemic of 1347-1352. The plague was spread by the rats, sailors, and cargo which were arriving in Sicily form the eastern Mediterranean. It then spread to other city-states of Italy. From Italy, the plague spreads to Austrian and central Europe. Its outbreaks persisted for the next 350 years.

Avoiding contact with the infected person and objects was important. City states didn't allow merchants and strangers to enter the cities. The strict separation between infected and healthy persons was also followed. The method of Quarantine was first introduced in 1377 in Dubrovnik on Croatia's Dalmatian Coast and the first hospital was opened by the Republic of Venice in 1423.

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