What is Norovirus Infection?
Norovirus infection, formerly known as the Norwalk virus, is a leading cause of foodborne disease outbreaks and acute non-bacterial gastroenteritis (diarrhea and vomiting illness) worldwide. A person can become infected with norovirus by consuming contaminated food or drink, or through contact with contaminated surfaces or items, such as plates, bowls, and spoons, etc.
Signs and Symptoms
A person will usually develop symptoms such as vomiting, stomach pain, and diarrhea within 12-48 hours of consuming contaminated food or drink. Coming into contact with bodily fluids of patients who carry the virus can also lead to infection. Symptoms usually last for about 24-72 hours from their onset.
Common symptoms include:
- Nausea, vomiting
- Watery or loose diarrhea
- Stomach pain
- Body and muscle aches
Although the nausea and vomiting experienced can be quite severe, physical examinations usually do not show any localized pain or abdominal cramps in a specific, precise area, making it difficult to separate diagnosis of norovirus infection from other diseases with similar symptoms and signs, such as intussusception, appendicitis, or other diseases and infections caused by food poisoning.
For patients who vomit or have diarrhea frequently throughout the day, this can lead to symptoms of severe dehydration, such as fever, extreme weakness, weak but rapid pulse, and low blood pressure.
Diagnosis of Norovirus infection involves a stool sample being collected and sent to the laboratory to be examined.
Currently, there are no specific medications to cure norovirus infection. Treatment, therefore, depends on care of the patient according to the types and severity of symptoms experienced. Most symptoms will usually improve within 3-4 days.
For patients with milder symptoms, oral rehydration solutions can be taken. Those who experience vomiting and diarrhea should have a diet of soft foods and can take anti-vomiting and abdominal pain medications according to their symptoms.
For those who experience stomach pain with vomiting and diarrhea, there is the danger of severe dehydration, which can lead to shock, low blood pressure, and even death. In such cases, hospitalization should be considered, along with intravenous fluid treatment and close monitoring of symptoms.
Patients most at risk of dehydration include small children, the elderly, or those with various already existing congenital diseases. Patients in these categories should receive special attention.
There is currently no vaccine available for the prevention of norovirus infection.
General prevention using good healthcare practices, such as, eating fresh food, using a serving spoon when sharing meals, and washing hands frequently can help to reduce the spread of infection.
Because this is a highly contagious disease, a few ways to help prevent the virus from spreading include the following steps:
- Wash hands frequently and thoroughly using soap and water for at least 15 seconds after using the restroom or changing a baby’s diaper, and before preparing or eating food. Alcohol-based hand sanitizers can be used, but washing hands with soap the better option.
- Avoid food and drinks that may not be clean – as the virus can remain within the environment, especially in water, for long periods of time.
- Wash fresh fruits and vegetables thoroughly. Ensure oysters or other shellfish are well-cooked before eating.
- Carefully dispose of any contaminated waste items, vomit, or fecal matter by using a damp cloth to clean up and securing the waste in a plastic bag.
- Diapers or any clothing contaminated with fecal matter should be separated immediately and washed as quickly as possible or disposed of appropriately.
- Wipe down contaminated areas clean with chlorine-based disinfectant.
- Do not cook or prepare food if you have been infected, as the virus can still be spread to others for up to 3 days after symptoms have passed.
- Infected children should not attend school or daycare, so as to prevent further spread of the virus.
- Avoid any traveling until you are fully recovered.