The CDC released a study this past week that has noted that deaths from gastrointestinal infections more than doubled from 1999 to 2007, to more than 17,000 a year from 7,000 a year. Of those who died, 83 percent were over age 65. Two thirds of the deaths were caused by a bacterium, Clostridium difficile, that people often contract in hospitals and nursing facilities, particularly when they have been taking antibiotics. But researchers were surprised to discover that the second leading cause of death from this type of illness was the common norovirus. It causes a highly contagious infection that can spread rapidly on cruise ships, dorms, prisons, and hospitals. Most people would classify norovirus as a minor illness but this study refocuses attention on this illness in a new light.
Problems with C. difficile are not new: Health officials first began warning in 2004 that a more virulent and drug-resistant strain had emerged. But few people anticipated what gains the bacteria would make. Among hospitalized patients, cases rose to 336,000 in 2009 from 139,000 in 2000. Deaths from the infection seem to have leveled off in the past few years, but researchers say they are still far too high and should be dropping, as other hospital-related infections are. CDC estimates that cases occurring outside hospitals run as high as three million annually. Overall, C. difficile infections cost $1 billion a year.
Two factors typically lead to the infection: taking antibiotics, which make the intestine vulnerable, followed by exposure to the bacteria or their spores in a hospital, clinic or nursing home that has not been properly disinfected. Spores can survive for weeks or maybe even months outside the body, and it takes bleach or other strong disinfectants to kill them.
Simple hygiene measures are highly effective, like cleaning surfaces with bleach and wearing gowns and gloves when treating infected people to avoid spreading germs to other patients. One of the disturbing and more disgusting facts about C. difficile is that it is very hard to remove from bare hands: neither soap and water nor alcohol-based hand sanitizers work very well. For health workers, it is much better to wear gloves, to avoid contaminating their hands in the first place.
About 20 million people a year in the United States get sick from norovirus, most often in the winter. It can quickly sweep through an environment in which people are living in close proximity such as a dorm. Just a small dose of the virus, a few particles, is enough to cause illness. The incubation period is short, and the virus can persist on surfaces for days or even weeks. Cold and moisture help it last.
Who are impacted severely from the norovirus? Older people are most likely to become severely ill and die from the virus, either from aspiration pneumonia caused by inhaling vomit or dehydration. The second highest death rate is in kids under 5 who become dehydrated, resulting in shock and heart problems.