Several centuries before the development of antiseptics (i.e. soap), diseases were often a death sentence, resulting in huge populations being wiped out from a single pandemic. Despite the huge strides in science and culture, the Renaissance had a lot of downsides regarding health and wellness. This was in part due to religious practices and the refusal to allow various sorts of medicines and surgical treatments to be tolerated, despite having the potential to save the patient(s). Regardless, the “why’s” are not the matter of importance, here. What is relevant, however, are the diseases themselves, including how they spread and why, with special focuses on the Black Plague and lead poisoning.
In the later middle ages, diseases were pretty common, and each represented new understanding of the body and in how to cure its ailments. What comes to mind is obviously the bubonic plague, but that is not the only issue peoples in this time period had to deal with. In France, a “Great Pox” not wholly unlike modern syphilis ran rampant, ultimately affecting “politics, the church and of course medical thinking” (Arrizbalaga). Because quarantines were not as effective as they generally are today, millions across Europe died from the disease, or infections stemming from the disease. What has been determined since is that this disease (and many of the other diseases Renaissance Europeans experienced) were likely caused from fleas and flea-bearing rodents (Arrizbalaga). Essentially, there was not much physicians or holy men could do at the time, and that is largely why so many people fell victim and died.
As with the syphilis-like disease previously mentioned, the Black Plague was brought to land by ship-borne rats, specifically their fleas (Benedictow). These fleas carried the disease to land, which subsequently affected the populace. Total, about 50 million Europeans died, with some areas having up to three-fourths of the population destroyed (Benedictow). Those afflicted were not treated well: despite poor medical treatment and flagellation making everything much, much worse, sufferers were also excluded from society (Allen). (A common practice was for priests to condemn “lepers” and other sick individuals to open-graves, proclaiming that due to their living-dead status, they would have to stay away from the healthy (Allen).)
Meanwhile, lead poisoning was also a huge problem in Renaissance Europe. Borgias and Catherine de Medici knew of lead’s diverse uses, but they adopted a “limited exposure, limited risk”-sort of policy (“Lead”). According to an article on the EPA’s website, what this resulted in was a chronic lead poisoning, which would not leave users insane or dead (as it would be with acute lead poisoning), but with a constant, mild discomfort (“Lead”). Similarly, painters like Michelangelo suffered from lead poisoning, simply because the paints were heavily based in lead (“Lead”). (Alchemists also used lead to divine gold, with obvious issues ensuing (Cisneros).)
Basically, what it all boils down to is that the Renaissance did not have a good grasp of diseases and how they spread, nor did they recognize that certain materials like lead should be monitored more than they were. As a result, millions (upon millions) died, and it would take years for the population to recover from the loss.
Allen, Peter L. "Epidemics, Historical." TheBody.com. Remedy Health Media, 1998. Web. 07 Feb. 2016. <http://www.thebody.com/content/art14016.html>.
Arrizbalaga, Jon, John Henderson, and Roger French. "Book Review — NEJM." New England Journal of Medicine. Yale University Press, 21 Aug. 1997. Web. 07 Feb. 2016.
Benedictow, Ole J. "The Black Death: The Greatest Catastrophe Ever." The Black Death: The Greatest Catastrophe Ever. History Today, 3 Mar. 2005. Web. 07 Feb. 2016. <http://www.historytoday.com/ole-j-benedictow/black-death-greatest-catastrophe-ever>.
Cisneros, Samantha. "Diseases of the Renaissance." Prezi.com. Prezi, Inc., n.d. Web. 07 Feb. 2016. <https://prezi.com/pshwdbnucxka/diseases-of-the-renaissance/>.
"Lead Poisoning: A Historical Perspective." EPA. Environmental Protection Agency, n.d. Web. 07 Feb. 2016. <http://www.epa.gov/aboutepa/lead-poisoning-historical-perspective>.