(WXYZ) — Norovirus is sickening hikers in Southern California and showing up at high levels across much of the country.
The highly contagious virus can spread quickly in communities, especially where people gather closely together.
We often think of norovirus as a winter illness, but cases can spike in spring too. This dreadful bug causes gastroenteritis, which is inflammation of the stomach and intestines. My patients often call it the "stomach flu," although it's not related to influenza.
Symptoms usually begin within 12 to 48 hours after exposure and can include nausea, vomiting, diarrhea, stomach cramps and sometimes a low-grade fever.
Now, the virus spreads through contaminated food or water, contact with infected people or by touching contaminated surfaces and then touching your mouth. In fact, norovirus is considered one of the most contagious viruses we know. On average, an infected person can infect up to seven other people.
As for the latest numbers, the Centers for Disease Control and Prevention's outbreak tracking system recorded nearly 1,200 outbreaks from August through early May. That’s lower than what we saw during the same period last year. But we know that many cases go unreported because most people recover at home. That’s where wastewater surveillance comes in. It can help public health officials track how widely the virus is spreading.
Right now, data show norovirus activity remains in the high range across much of the country, with levels staying elevated throughout the past three weeks. And that includes right here in the Midwest.
Right now, multiple norovirus strains are spreading. That includes the long-standing GII.4 strain, which many of us have been exposed to, and a newer variant, GII.17. The good news is that there's no evidence that the newer strain causes more severe illness. It can spread more easily because fewer folks have built up immunity to it.
As for prevention, wash your hands thoroughly with soap and water, especially after using the restroom and before eating or preparing food. It’s also important to disinfect contaminated surfaces, wash fruits and vegetables, cook seafood thoroughly and avoid preparing food for others if you’re sick.
If you do become infected, there is no specific treatment, but oral rehydration fluids are recommended. Most people recover within a few days. But the illness can be especially serious for young children, older adults and anyone who becomes dehydrated. If symptoms are severe or dehydration develops, seek medical attention promptly.
