Article Text
A highly contagious strain of norovirus known as GII.17[P17] is spreading across the United States, including the Northeast, as regional urgent care clinics report an increase in cases.
MedStar Health Urgent Care has seen norovirus cases rise 5% to 10% from last year across its 33 clinics as of Jan. 13, according to a spokesperson. Because not everyone with symptoms is tested, the figures may not capture every infection.
Norovirus can cause acute gastroenteritis, marked by sudden, severe vomiting and diarrhea. Symptoms usually begin 24 to 48 hours after exposure and last two to four days.
The virus spreads easily through contaminated food, water and surfaces, as well as direct contact with an infected person. Viral particles may also enter the air when someone vomits.
Jon Gonella, a MedStar physician assistant with 25 years of experience treating viral illnesses, said norovirus commonly reaches surfaces through the fecal-oral route. An infected person can leave the virus on a bathroom door, counter or another object after using the restroom, allowing the next person who touches it to become exposed.
Frequently contaminated objects, known as fomites, can include doorknobs, countertops, furniture, school desks, phones, clothing, toys and eating utensils. As few as 10 viral particles may be enough to infect someone, according to the Centers for Disease Control and Prevention.
Most outbreaks occur when people fail to wash their hands after using the bathroom. Leafy greens, fresh fruit and shellfish such as oysters are among the foods commonly linked to outbreaks.
Dehydration Is the Main Concern
There is no antiviral treatment for norovirus. Care generally centers on maintaining hydration and eating a bland diet until symptoms subside.
Children and older adults are particularly vulnerable to dehydration. Changes in mental status—including lethargy or reduced alertness—are warning signs that a patient needs medical attention or emergency care. Repeated vomiting or diarrhea may also cause a person to become unusually pale.
Hand sanitizer alone is not enough to stop the virus. Gonella said alcohol-based sanitizers are generally ineffective against norovirus and recommended thorough handwashing with soap and water.
He advised disinfecting contaminated surfaces after a vomiting or diarrhea episode with a mixture of household bleach and water, using 5 to 25 tablespoons of bleach per gallon of water. Fruits and vegetables should also be washed carefully.
People suspected of having norovirus should avoid preparing food for anyone else until at least two days after their symptoms have ended.
Norovirus causes an estimated 19 million to 21 million illnesses, 109,000 hospitalizations and about 900 deaths annually in the United States. Most deaths occur among older adults.