A to Z
Data &
Forms &
News &
Licensing &
Rules &
Public Health

Calicivirus (Norovirus, Sapovirus, Winter Vomiting Disease)

Caliciviruses (norovirus and sapovirus) cause outbreaks of viral gastroenteritis in closed and semi-closed populations such as long term care facilities and schools. Caliciviruses can also cause outbreaks of foodborne illness. Viral gastroenteritis has a disinctive clinical syndrome of diarrhea and vomiting, comes on rapidly, and leaves victims miserably ill for a couple of days. Caliciviruses are very, very contagious.  Because calicivirus outbreaks occur mainly in the colder months, an early name for such outbreaks was “winter vomiting disease.”

Disease Reporting

What is required?

Individual calicivirus cases are not legally reportable conditions; however, outbreaks of calicivirus are reportable. (Scroll to OAR section 333-018-0015.) The Oregon Public Health Division has been tracking calicivirus outbreaks specifically in nursing homes and similar settings since 2003.

Reported Outbreaks in Long-Term Care Facilities

Norovirus in Long-Term-Care Facilities: Annotated Report of Stakeholder Meeting and Interviews, March 2014 (pdf)


Oregon Norovirus: 
July 7, 2014 (pdf) |  May 3, 2013 (pdf) | June, 7, 2013 (pdf) | July 5, 2013 (pdf) | Aug 2, 2013 (pdf) | Nov 1, 2013 (pdf)

Laboratory-confirmed norovirus and norovirus-like outbreaks by setting, Oregon, August 2013 thru June 2014 (pdf)

Gastroenteritis outbreaks by confirmation and infection, Oregon 2003–2012 (pdf)
Norovirus outbreaks are highlighted with red. Note that norovirus outbreaks account for 75% of oubreaks with stool specimens available for testing.

Gastroenteritis outbreaks by transmission modes and settings, Oregon 2003–2012 (pdf)
Note that the majority of reported gastroenteritis outbreaks occured in institutional cohorts.

Gastroenteritis outbreaks in long-term care facilities, Oregon 2003-2012 (pdf)
Note that majority of reported gastroenteritis outbreaks in long-term care are caused by norovirus.

See Also

Investigating gastroenteritis outbreaks in long-term care facilities and hospitals

CDC Norovirus web page