Q: What are noroviruses?
A: A group of viruses that cause the "stomach flu," or gastroenteritis. Viruses are different from bacteria and parasites, some of which can cause illnesses similar to norovirus infection. Viruses are not affected by antibiotics and cannot grow outside a person's body.

Q: What are the symptoms of illnesses caused by noroviruses?
A: Nausea, vomiting, diarrhea and some stomach cramping. Sometimes people have low-grade fevers, chills, headaches, muscle aches and fatigue. The illness often begins suddenly, but is usually brief, with symptoms lasting one or two days. In general, children experience more vomiting than adults. Most people with norovirus illness have both of these symptoms.

Q: What are the names of illnesses caused by noroviruses?
A: Stomach flu: This "stomach flu" is not related to the flu (or influenza), which is a respiratory illness caused by influenza virus.

• Viral gastroenteritis: The most common, it's an inflammation of the stomach and intestines.
• Acute gastroenteritis
• Nonbacterial gastroenteritis
• Food poisoning (although there are other causes of food poisoning)
• Calicivirus infection

Norovirus diseases usually are not serious, although sometimes people become dehydrated. Dehydration is usually only seen among the very young, the elderly and people with weakened immune systems. Infected people are unlikely to become long-term carriers of noroviruses.

Q: How do people become infected with noroviruses?
A: Eating food or drinking liquids contaminated with noroviruses

Touching surfaces or objects contaminated with noroviruses, then placing their hands in their mouths

Having direct contact with a person who is infected and showing symptoms -- for example, caring for someone with an illness, or sharing foods or eating utensils with someone who is ill

Q: Are noroviruses contagious?
A: Noroviruses are very contagious. Particular care should be taken with young children in diapers who may have diarrhea.

Q: How long are people contagious?
A: People infected with noroviruses are contagious from the moment they begin feeling ill to at least three days after recovery. Some people may be contagious for as long as two weeks.

Q: What treatment is available for people with norovirus infections?
A: There is no antiviral medication that works against noroviruses and there is no vaccine to prevent infection. Norovirus infection cannot be treated with antibiotics, which fight bacteria and not viruses.

Q: Can norovirus infections be prevented?
A: You can decrease your chance of coming in contact with noroviruses by following these steps:

• Frequently wash your hands, especially after toilet visits and changing diapers, and before eating or preparing food.
• Carefully wash fruits and vegetables, and steam oysters before eating them.
• Thoroughly clean and disinfect contaminated surfaces immediately after an episode of illness by using a bleach-based household cleaner.
• Immediately remove and wash clothing or linens that may be contaminated with virus after an episode of illness.
• Flush or discard any vomitus and-or stool in the toilet and make sure that the surrounding area is kept clean.
• Infected people should not prepare food while they have symptoms and for three days after they recover. They also should drink plenty of fluids, especially juice or water.

Source: The Centers for Disease Control and Prevention