The revolution brought new diseases unknown to the people. As a result, the disease-causing organisms were modified and made them even more dangerous to humans because they lacked any type of immunity to disease. One disease that transformed once introduced to the New World was syphilis. Syphilis began as a disease caused by bacteria, but eventually became a sexually transmitted infection and was identified as likely causing endemic disease. These infections have become more harmful and serious due to different environmental factors. In fact, other disease problems arose with population overcrowding, leading to an escalation of sexual acts that occurred more frequently as people began to engage in prostitution and some became more promiscuous, which likely fueled disease transmission. In addition to diseases due to lack of immunity and diseases transmitted through sexual contact, other complications have arisen due to economic growth. Some of these changes have impacted the city's residents by creating problems such as: how to eliminate urban waste and pollution that has contaminated water resources, as well as air pollution. Some areas remained in a shortage situation, which increased the likelihood of virus transmission. Transmitted viruses became epidemics, some of these diseases were for example measles, and typhoid, diphtheria and smallpox were among the best known. Other illnesses, more serious in nature, were those caused by overcrowded living spaces and possibly by the harsh conditions caused in their working environment, including tuberculosis and pneumonia. Another major problem arose with death rates compared to birth rates for people living in urban areas. This generated concern that could not be