The erroneous practices used during the bubonic plague outbreak in Europe to slow the spread of the disease included

The black plague or bubonic plague was a serious infection caused by the bacterium Yersinia pestis, which devastated Europe during the second half of the 14th century.

The spread of the disease, initially, occurred through the flea of rodents infected with the bacillus. In a more advanced stage, the disease began to spread by air, through sneezes and droplets. At that time, medicine was drastically elemental, there was no treatment for serious infections and hygiene and housing conditions were precarious, which contributed to the spread of rodents and the disease. There was no basic sanitation, human beings lived with their own waste, most houses were unhealthy, people used to share used sheets and treat the sick without any precaution, under the same air and in direct contact with wounds.

There was the dissemination of religious practices in order to postpone the spread of the disease. Often the disease was considered a divine punishment, and the patient was to blame. Many people used faith as a preventive mechanism, but they maintained anti-hygienic practices. Another common practice was to blame and persecute certain groups, like the Jews, committing murders as if this were a way to eliminate the disease.