What factors made slum neighborhoods breeding grounds for disease and epidemics at the turn of the twentieth century?

As American cities industrialized throughout the nineteenth century, infectious diseases emerged as a real threat. The introduction of new immigrants and the growth of large urban areas allowed previously localized diseases to spread quickly and infect larger populations. Towns grew into cities as industrialization sparked urban migration from rural communities in both the United States and Europe. The increased demand for cheap housing by urban migrants led to poorly built homes that inadequately provided for personal hygiene. Immigrant workers in the nineteenth century often lived in cramped tenement housing that regularly lacked basic amenities such as running water, ventilation, and toilets. These conditions were ideal for the spread of bacteria and infectious diseases. Without organized sanitation systems, bacteria easily passed from person to person through the water and sewage. As a result, many of America’s largest urban areas like New York, Boston, Philadelphia, and Washington DC fell prey to a rash of infectious diseases in the middle and end of the nineteenth century.

Coming to America

Mary Mallon, otherwise known as “Typhoid Mary,” is the most famous of these carriers. An Irish immigrant cook living in New York City, Mary was the first recorded carrier of typhoid fever. As a cook, Mary unknowingly spread the disease to many of the wealthy families she worked for across the city. In 1906, Mary began working in a summer rental home for a New York banker. Over the summer, typhoid fever struck over half of the people living in the home and the banker became worried that he would not be able to rent out the house again until he found the source of the disease. The banker hired George Soper to investigate the outbreak. ref]Evelynn Hammonds, “Infectious Diseases in the 19th-Century City” [/ref] Soper determined that none of the food or water was contaminated so it must have been a cook who spread the disease. After tracing Mary’s work records back to 1900, Soper realized that Mary not only infected this family, but many others as well.29 Soper attempted to explain the situation to Mary, but she refused to believe him. In 1907, Soper turned over his findings to the New York City health department. The health department proceeded to apprehend Mary and quarantine her in a hospital. By this point, Mary was extremely untrusting of any health officials and frequently acted aggressively towards them.30 Tests performed on Mary confirmed the assumption that she was a carrier. For three years, Mary was forcibly held in health department custody. Mary was eventually released under the condition that she never cook again.31 However, she was recaptured shortly thereafter when another outbreak of typhoid was traced to her kitchen. Mary lived in forced isolation for the rest of her life, until her death in 1938.32

The story of “Typhoid Mary” has remained popular to this day, not because Mary Mallon was terribly unique as a carrier of typhoid fever, but because her tale epitomizes an entire era. Mallon was the first known healthy carrier of typhoid fever, but definitely not the last. At the beginning of the twentieth century, approximately one hundred New Yorkers became carriers of the disease each year. Mallon was neither the most deadly carrier nor the only carrier to disobey the health department’s guidelines. A man named Tony Labella is attributed to spreading typhoid fever to almost three times as many people as Mary and Alphonse Cotils, a bakery owner and typhoid carrier.33 “Typhoid Mary”, though, has found a prominent place in America’s history books because her story is the same story of thousands of others in the late nineteenth century. Mallon immigrated across the Atlantic to America’s largest city in search of a better life. What she found was a dirty and crowded city that offered work that came with low pay and long hours. Mary’s contraction and subsequent spread of typhoid fever is the perfect example of the cramped living quarters, poor working conditions, and poor hygiene that many late nineteenth-century immigrants faced.

in the host-cell chemokine receptor CCR5, which reduces the risk of acquiring HIV infection after exposure (Sullivan et al., 2001). As another example, certain major histocompatibility complex class I molecules have been shown to reduce the risk of dying from HIV infection (Kaslow et al., 1996; Gao et al., 2001). Likewise, several different mutations or polymorphic systems influence the susceptibility to or likelihood of death from meningococcal infection (Read et al., 2000; Nadel et al., 1996; Westendorp et al., 1997). Numerous other examples exist of genetic associations with diseases, including cancers and chronic diseases, and the list is growing rapidly (Hill, 2001; Topcu et al., 2002; Chen et al., 2002a; Calhoun et al., 2002; Helminen et al., 2001; Pain et al., 2001).

Host susceptibility to infection is aggravated by malnutrition. A strong and consistent relationship has been found between childhood malnutrition and increased risk of death from diarrhea, acute respiratory infection, and possibly malaria (Rice et al., 2000). Conversely, infectious processes, especially those associated with diarrhea, drive malnutrition in young children (Mata, 1992; Mata et al., 1977), so that diarrheal illness is both a cause and an effect of malnutrition (Guerrant et al., 1992; Wierzba et al., 2001; Lima et al., 1992). Clinically, malnutrition is characterized by inadequate intake of protein, energy, and micronutrients and by frequent infections or disease (WHO, 2002d). Malnutrition has been associated with 50 percent of all deaths among children worldwide (Rice et al., 2000). In 2000, an estimated 150 million of the world’s children under age 5 were malnourished on the basis of low weight for age (WHO, 2002d). More than two-thirds (70 percent) of these children were in Asia, especially southern Asia. The number of malnourished children living in Africa—26 percent of the world’s malnourished children—has risen as a result of population growth in the region, as well as natural disasters, wars, civil disturbances, and population displacement (WHO, 2000b).

Malnutrition diminishes host resistance to infection through a number of mechanisms. Virtually all bodily processes and physical barriers that keep infectious agents from invading the host are affected. These include the skin, mucous membranes, gastric acidity, absorptive capacity, intestinal flora, cell-mediated immunity, phagocyte function, and cytokine production (Chandra, 1997; Levander, 1997). Although multiple-nutrient deficiencies are much more common than single-nutrient deficiencies, lack of even one vitamin or mineral (e.g., zinc; selenium; iron; copper; vitamins A, C, E, B-6, and folic acid) can impair the immune response. For example, vitamin A deficiency significantly increases the risk of severe illness and death from common childhood infections, such as diarrheal disease and

Which factors are causing diseases in slum area?

What are the major factors which cause epidemics?

What disease epidemics were common in slums?

Why has urbanization increased the risk of disease epidemic in the modern era?