From the Guidelines
Norovirus is a highly contagious virus that causes gastroenteritis, and treatment is primarily supportive, focusing on preventing dehydration through oral rehydration solutions, with most people recovering within 1-3 days without specific treatment. The management of norovirus infection is mainly focused on preventing dehydration and managing symptoms, as there is no specific antiviral treatment available 1.
Key Considerations
- The incubation period of norovirus is typically 12-48 hours, followed by symptoms such as vomiting, diarrhea, abdominal pain, and low-grade fever 1.
- Transmission occurs through person-to-person contact, contaminated food and water, and fomites, with an estimated infectious dose as low as 18 viral particles 1.
- Prevention is crucial, and thorough handwashing with soap and water for at least 20 seconds is essential, as alcohol-based sanitizers are less effective against norovirus 1.
- Infected individuals should avoid preparing food for others for at least 48 hours after symptoms resolve and should stay home from work or school until symptom-free for 24-48 hours to prevent community spread.
Management
- Oral rehydration solutions like Pedialyte or homemade solutions (1 teaspoon salt, 8 teaspoons sugar in 1 liter of water) should be used to prevent dehydration, with adults drinking at least 2-3 liters of fluids daily while ill, and children receiving frequent small amounts.
- Over-the-counter medications like loperamide (Imodium) can help control diarrhea in adults but should be avoided in children.
- Anti-nausea medications such as ondansetron may be prescribed in severe cases.
Prevention
- Thorough handwashing with soap and water for at least 20 seconds is essential.
- Infected individuals should avoid preparing food for others for at least 48 hours after symptoms resolve.
- Infected individuals should stay home from work or school until symptom-free for 24-48 hours to prevent community spread.
- Environmental surfaces should be disinfected using a chlorine bleach solution with a concentration of 1,000–5,000 ppm (1:50–1:10 dilution of household bleach [5.25%]) or other Environmental Protection Agency (EPA)–approved disinfectant 1.
From the Research
Norovirus Overview
- Norovirus (NoV) is an enteric non-enveloped virus and the leading cause of gastroenteritis across all age groups 2
- It is responsible for around 200,000 deaths annually and outbreaks are common in small communities such as educational and care facilities 2
- Norovirus is transmitted via the faecal-oral route and infection with it results in asymptomatic cases or gastrointestinal disease 2
Transmission and Prevention
- The virus can spread through multiple transmission routes, of which person-to-person and foodborne are the most important 3
- Outbreak management relies on sound infection control principles, including hand hygiene, limiting exposure to infectious individuals, and thorough environmental decontamination 3
- Stringent hygiene measures are vital to contain the virus, and isolating infected individuals can limit its spread 4
Treatment and Control
- There are no specific control measures against NoV, therefore common practices are used against it such as hand washing 2
- Several treatment strategies have been suggested in case reports: nitazoxanide, ribavirin and enterally administered immunoglobulin with varying results 5
- Favipiravir is also suggested but not tested on humans, highlighting the need for further research 5
- No vaccine is available, but the HIL-214 candidate passed clinical phase 2b and shows promise 2
High-Risk Groups
- Norovirus illness can be life-threatening, especially in immunocompromised patients who often require prolonged hospitalization and intensive supportive care 6
- For immunocompromised patients, norovirus gastroenteritis can last for several years and result in villous atrophy and lead to severe malnutrition, dehydration, electrolyte imbalance and continuous viral shedding 5