Deaths from Gastroenteritis Caused by C. difficile and Norovirus Double

The number of people who died from gastroenteritis (inflammation of the stomach and intestines that causes vomiting and diarrhea) more than doubled from 1999 to 2007, according to a study by the Centers for Disease Control and Prevention. The findings will be presented today at the International Conference on Emerging Infectious Diseases in Atlanta.

CDC scientists used data from the National Center for Health Statistics to identify gastroenteritis-associated deaths from 1999 to 2007 among all age groups in the United States.

Gastroenteritis is a major cause of death worldwide, says lead author Aron Hall, DVM, MSPH, of the CDCs Division of Viral Diseases. By knowing the causes of gastroenteritis-associated deaths and whos at risk, we can develop better treatments and help health care providers prevent people from getting sick.

Over the eight-year study period, gastroenteritis-associated deaths from all causes increased from nearly 7,000 to more than 17,000 per year. Adults over 65 years old accounted for 83 percent of deaths. Clostridium difficile (C. difficile) and norovirus were the most common infectious causes of gastroenteritis-associated deaths.

There was a fivefold increase, from approximately 2,700 to 14,500 deaths per year, for C. difficile, a type of bacteria often associated with health care settings. C difficile, which causes diarrhea, accounted for two-thirds of the deaths. Much of the recent increase in the incidence and mortality of C. difficile is attributed to the emergence and spread of a hypervirulent, resistant strain of C. difficile.

Norovirus was associated with about 800 deaths annually, though there were 50 percent more deaths in years when epidemics were caused by new strains of the virus. Norovirus is highly contagious. It spreads through person-to-person contact and contaminated food, water, and surfaces. People can get norovirus illness throughout the year, but cases peaked between December-February. Norovirus causes more than 20 million illnesses annually, and it is the leading cause of gastroenteritis outbreaks in the United States.

While C. difficile continues to be the leading contributor to gastroenteritis-associated deaths, this study shows for the first time that norovirus is likely the second leading infectious cause, says Hall. Our findings highlight the need for effective measures to prevent, diagnose, and manage gastroenteritis, especially for C. difficile and norovirus among the elderly.