NEW STRAIN OF NOROVIRUS, GII.4 SYDNEY DETECTED IN DELAWARE: PREVENTION IS BEST DEFENSE

The Delaware Division of Public Health (DPH) is urging the public to take precautions to prevent possible exposure and spread of norovirus, an illness that typically occurs during the winter months. After the first report received on January 3, 2013, DPH has investigated and confirmed nine norovirus clusters. To date, the DPH lab has determined one of which is the GII.4 Sydney subtype highlighted in a recent Centers for Disease Control and Prevention (CDC) announcement. Results on the other Delaware clusters are pending.

According to the CDC, this virus strain is currently the leading cause of norovirus outbreaks in the US. The new type was first identified in Australia in 2012. While this type is new to the United States, it is not known to be more virulent then other similar strains of G11.4 identified here.

A disease cluster is the occurrence of more than the expected number of people diagnosed with a certain disease within a specific group, a geographic area or a period of time. Disease clusters may be suspected when people report that several family members, friends, neighbors, coworkers or community members have been diagnosed with the same illness. Clusters are commonly confirmed in such group settings as long-term care facilities, schools, hospitals and day cares. At this time last year, four outbreaks were confirmed.

Gastrointestinal illness caused by norovirus is unpleasant and can be severe for those who are elderly or have an underlying health condition. Symptoms include nausea, vomiting, diarrhea, and stomach cramping. Some people may experience fever, chills, headache, muscle aches, or a general sense of tiredness. The symptoms can begin suddenly and an infected person may go from feeling well to very sick in a very short period of time. In most people, the illness lasts for one to two days. People with norovirus illness are contagious from the moment they begin feeling sick until at least three days after they recover; some people may be contagious for even longer. Infection can be more severe in young children and elderly people. Dehydration can occur rapidly and may require medical treatment or hospitalization. Although there are no specific medications to treat norovirus, drinking plenty of liquids to prevent dehydration is important.

Noroviruses are easily transmitted by touching a contaminated surface as well as by direct contact with an infected person or by eating food or drinking liquids that have been contaminated with the virus.

The best course of action is prevention. DPH recommends the following steps to prevent exposure to and spread of norovirus.

• Noroviruses can be difficult to kill with normal cleaning and disinfecting procedures. Surfaces that have been contaminated with stool or vomit should be cleaned immediately and disinfected with a freshly prepared diluted bleach solution (1 part bleach:10 parts water) or a bleach-based household cleaner. Never use undiluted bleach.
• If you are ill with vomiting or diarrhea, you should not go to work, school, or attend daycare.
• Healthcare facilities, such as nursing homes and hospitals, may restrict visitation of sick family members or friends for the safety of not only the ill persons but also the visitors.
• Wash your hands frequently and thoroughly with soap and water. This is one of the most effective ways to protect yourself and others against norovirus since hand sanitizers alone are not as effective against the virus as handwashing.

The norovirus is not related to influenza nor linked to the high number of influenza cases so far this flu season. For more information about norovirus, see the DPH Web site at www.dhss.delaware.gov/dhss/dph/files/norwalkfaq.pdf.

Delaware Health and Social Services is committed to improving the quality of the lives of Delaware's citizens by promoting health and well-being, fostering self-sufficiency, and protecting vulnerable populations.