The Victorian era was a time of great advances in medicine. But like in earlier centuries, people did die regularly of disease--cholera, influenza, measles etc. The one I find most fascinating is tuberculosis, or consumption as they called it back then.
Well for one thing, it was the leading cause of death in the U.S. in the 19th century. From the beginning of the century thru 1870, it was the cause of 1 in 5 deaths, or 20%! Compare that with the "scourge" of the late 20th century, AIDS, which is does not even hit the top 5 causes of death in the U.S. http://library.thinkquest.org/16665/causes.htm
Like those infected with AIDS, though, victims of tuberculosis could live a very long time. It was a wasting disease (thus the 19th century term consumption), its sufferers not dying within days or weeks, but living with attacks and remissions that could last for years or decades. It allowed those infected to get married, have children, and pass the disease on to them. Families, therefore, could suffer from the infection for 2 or even 3 generations, passing it from parent/grandparent to children. In fact, for much of the century, the physicians thought the disease was hereditary, not contagious. They believed that families had a predisposition to the illness.
We now know, of course, that tuberculosis is contagious, transmitted through the air. Why didn't people understand that back then, when it was considered likely with other illnesses, such as colds and influenza? I suspect that's because first and foremost, having the TB bacteria doesn't necessarily mean you will develop the disease. In fact, only 5-10% of the people who have the bacteria ever develop the disease. http://www.who.int/mediacentre/factsheets/fs104/en/
Secondly, unlike diseases such as influenza or cholera, it can takes years to develop tuberculosis. You may have been exposed to it by a train passenger in 1850 and not develop symptoms for until 1855. Who could say, then, where you got the disease?http://www.concordma.com/magazine/winter03/tuberculosis.html
The majority of this information came from Living in the Shadow of Death, Tuberculosis and the social Experience of Illness in American History by Sheila M. Rothman