Norovirus, often called the 'winter vomiting illness', is a highly contagious family of viruses causing severe gastroenteritis with vomiting and diarrhea. Spreading easily through the fecal-oral route, it requires very few viral particles to infect and can persist on surfaces for weeks, making diligent hygiene crucial for prevention.
Norovirus encompasses about 50 strains of highly contagious viruses, causing infectious gastroenteritis characterized by sudden and severe vomiting and watery diarrhea. Globally, an estimated 684 million people contract it annually, with peaks from December to February in the Northern Hemisphere. The virus spreads primarily via the fecal-oral route, as tiny viral particles from an infected person's saliva or feces can contaminate hands, food, or drink. It is incredibly contagious, requiring less than 20 virus particles to cause infection, and infected individuals can shed billions of particles. Transmission can also occur through aerosolized particles during vomiting. People become contagious two days before symptoms appear and can remain so for days or even weeks after recovery. High-risk environments include eldercare facilities, daycares, airports, and cruise ships. Symptoms, which appear suddenly, include abdominal cramping, sweating, chills, nausea, vomiting, and very watery diarrhea. While most cases resolve within three days, it's an extremely unpleasant illness causing fatigue, low-grade fever, and headaches. Most healthy adults and older children recover without medical intervention, but norovirus causes 570-800 deaths and 70,000 hospitalizations annually in the US, particularly affecting children under five, individuals over 65, and the immunocompromised, who are at high risk for dehydration and kidney injury. These vulnerable groups should seek medical attention if they cannot keep liquids down. There is no specific treatment to shorten the illness, but staying hydrated with water, Gatorade, or ice chips is crucial. Antiemetics like Dramamine can help with nausea, but anti-diarrhea medications like Imodium should be avoided as they can prolong the infection by trapping the virus. Prevention is key as there is no vaccine due to the virus's complexity and frequent mutations. Essential prevention strategies include: * **Handwashing**: Frequent and thorough handwashing with soap and water for at least 20 seconds is paramount, as alcohol-based hand sanitizers are ineffective against norovirus. Infected individuals should avoid preparing food or caring for others. * **Isolation**: Designate a separate bathroom for sick household members if possible and limit close contact. * **Cleaning**: Disinfect contaminated surfaces with diluted bleach (1 cup per gallon of water) or undiluted 3% hydrogen peroxide, wearing disposable gloves. Most disinfecting wipes are ineffective; specialized bleach wipes may be needed. * **Laundry**: Wash contaminated items separately on hot (up to 158F/70C) with bleach. * **Avoid communal dining**: Be cautious with buffets and potlucks, especially during peak season, due to shared utensils and varied food sources. Immunity to norovirus is not robust or long-lasting, meaning reinfection can occur every few months.
