Norovirus is a common and highly contagious virus that typically causes acute gastroenteritis, an inflammation of the stomach and intestines. This illness often involves symptoms such as sudden onset of vomiting, diarrhea, and stomach pain. While frequently referred to as “stomach flu,” norovirus is not related to influenza, which is a respiratory illness.
Understanding Norovirus Recurrence
Experiencing norovirus infection does not guarantee lasting protection against future encounters with the virus. It is possible to contract norovirus multiple times throughout one’s life. This occurs primarily due to two factors: the existence of numerous distinct norovirus strains and the short-lived nature of the immunity acquired after an infection.
There are many different types of norovirus. An infection with one specific strain provides some immunity to that particular strain, but it offers little to no protection against other diverse strains.
Even against the same strain, the immunity developed after an infection is not permanent. Research suggests this protection is often short-lived, typically lasting from several months to a few years. This temporary immunity makes reinfection with the same strain possible over time.
Preventing Future Norovirus Infections
Adopting specific hygiene practices is crucial for reducing the risk of future norovirus infections. Thorough and frequent handwashing with soap and running water is considered the most effective method to remove norovirus particles from hands. This is particularly important after using the restroom, changing diapers, and before eating or preparing food.
Alcohol-based hand sanitizers are less effective against norovirus because the virus lacks a lipid envelope, making it more resistant to alcohol. While they may serve as an adjunct, hand sanitizers should not replace proper handwashing with soap and water.
Practicing food safety is another important preventive measure. This includes carefully washing fruits and vegetables under running water and thoroughly cooking shellfish, such as oysters, to the appropriate temperature. Individuals who are sick with norovirus should avoid preparing food for others to prevent spreading the illness.
Cleaning and disinfecting contaminated surfaces can significantly limit the spread of the virus. Norovirus can survive on surfaces for days. Using a bleach-based cleaner or an EPA-approved disinfectant on high-touch areas like kitchen counters, bathroom fixtures, and doorknobs is recommended. Staying home when experiencing symptoms and for at least 48 hours after symptoms have resolved helps prevent transmission to others.
When to Consult a Doctor
While most norovirus infections resolve on their own within one to three days, certain symptoms or populations warrant medical attention. Dehydration is a significant concern, especially in young children, older adults, and those with weakened immune systems. Signs of dehydration include decreased urination, dry mouth and throat, dizziness, lethargy, or rapid heartbeat.
Medical consultation is advisable if symptoms such as persistent vomiting or diarrhea make it impossible to keep fluids down. Other indicators for seeking professional care include severe abdominal pain, bloody diarrhea, or a high fever. If symptoms do not improve after a few days or worsen, it is also appropriate to contact a healthcare provider.