Treatment for Norovirus Infection
Norovirus typically resolves without treatment; however, dehydration is a concern.
Collecting a stool sample and using molecular methods to find viral RNA is the preferred method to test for norovirus in the public health world. In many cases, however, diagnosis is made based on symptoms. Most people who become ill recover within 24 to 48 hours after symptoms with just rest and fluids to prevent dehydration. Antibiotics are not effective, as the illness is caused by a viral pathogen.
There is no specific treatment available for norovirus. In most healthy people, the illness is self-limiting; however, outbreaks among infants, children, elderly, and immune-compromised populations may result in severe complications among those affected. Death may result without prompt measures.
A vital part of therapy for norovirus is the replacement of fluids and minerals such as sodium, potassium, and calcium—otherwise known as electrolytes—lost due to persistent vomiting and diarrhea. This rehydration can be done either by drinking large amounts of liquids, or intravenously.
Recent research has focused on the potential for developing a norovirus vaccine. Researchers indicate that coming up with a norovirus vaccine would be similar to vaccinating for influenza—by using screening in order to select for the most prevalent strains. The success of a norovirus vaccine will depend largely on the duration of immunity it can confer. While modeling studies have suggested that naturally-induced norovirus immunity could last 4 to 9 years, challenge studies have found that immunity only lasts from 2 months to 2 years after norovirus inoculation, although norovirus inoculums were significantly higher than would be observed in naturally-acquired infections. Currently, no clinical data from challenge studies have been published to verify longer immunity durations. Norovirus vaccine clinical trials have shown moderate vaccine efficacy, but participants were challenged with vaccine-specific norovirus strains only four weeks after receiving the second dose of the vaccine. Results from longer-term immunity studies are currently unavailable.