The “Stomach Flu” Virus
We often write about disaster situations that we personally experience. We’ve been through hurricanes, tornadoes, and epidemics, just to mention a few. Recently, our home in Gatlinburg, Tennessee was threatened by the wildfires there, which killed 14 and wiped out more than 1700 buildings and over 100 on the mountain where the house is located.
We’ve written about a number of medical issues that we’ve experienced as well. For example, I converted to positive for Tuberculosis during my work with Cuban refugees during the 1980 Mariel boatlift. I still carry a small walled-off nodule on X-ray, even after months of multi-drug therapy.
On a recent trip to New York City to visit our daughter, we both experienced a medical issue so common that it surprised us that we haven’t yet written about it: acute gastroenteritis, or the “Stomach Flu”. When this infection hits you, it makes even the healthiest individual miserable. Nurse Amy required an urgent care visit, no small issue in a strange and heavily-populated city. She was just one of nearly 2 million outpatient visits caused by norovirus in the U.S. every year.
Norovirus is the most common cause of viral gastroenteritis in humans. It was originally called “Norwalk Virus”, after the area where it was first identified in the 1960s. Since then, it’s been blamed for 50% of all gastroenteritis in the U.S. Worldwide, there are more than 200 million cases of norovirus infection a year. It affects people of all ages, but it’s particularly dangerous in the elderly, the very young, and those with weakened immune systems. Winter is the most common time for outbreaks.
Norovirus is very contagious (just 5-20 viral particles can cause illness) and is easily transmitted through contaminated food or water, close personal contact, and by air droplets from vomit, contaminated food counters, and even toilet flushes. Infection can be passed from person to person for a time even after apparent recovery.
Here’s how contagious the norovirus is: In one outbreak reported in 1998, 126 people were dining at a restaurant when one person vomited onto the floor. Despite a rapid cleanup, 52 fell ill within three days. More than 90% of the people who later dined at the same table reported symptoms. More than 70% of the diners at a nearby table got sick; at a table on the other side of the restaurant, the rate was still 25%.
Norovirus is a hardy microbe, and is known to survive for long periods outside a human host. It can live for weeks on countertops and up to twelve days on clothes. It can survive for months in still water. Disinfectants containing chlorine, however, like bleach will quickly eliminate it, as will sufficient heat.
The symptoms of the stomach flu include nausea and vomiting, watery diarrhea, and (sometimes severe) abdominal pain, usually within 12 to 48 hours of exposure. Along with this, muscle aches, headache, and fever may be seen. Luckily, life-threatening illness is rare, with dehydration being the main danger in those infected with the virus.
Unlike some viruses, immunity to norovirus is only temporary, maybe six months, after recovery.
Outbreaks of norovirus infection often occur in closed spaces such as cruise ships, nursing homes, schools, camps, and prisons. Shellfish, such as oysters, and salad ingredients are the foods most often implicated in norovirus outbreaks. In our case, it might have been a kiosk advertising “the World’s Best Hot Dogs”.
As is the case with most viruses, there is no cure for norovirus infection. Antibiotics will not be effective, as they are meant to kill bacteria, not viruses. Treatment involves staying well-hydrated. Dehydration can be noted by these symptoms:
· Dry mouth
· Decrease in quantity or dark color of urine
· Dizziness when standing up
· Decreased elasticity of skin (it “tents” when pulled)
· No tears when crying or unusual irritability in infants
Using antidiarrheal meds like loperamide (Imodium) and anti-vomiting drugs like Ondansetron (Zofran) may also help.
A cure may not be available but prevention is another issue. To decrease the chance of norovirus infection:
· Wash your hands frequently with soap and water (norovirus is relatively resistant to alcohol), especially after using the restroom or handling food. Be especially sure to do this for 2 weeks after becoming infected (yes, you can be contagious for that long).
· Wash food before cooking; cook shellfish thoroughly
· Frequently disinfect contaminated surfaces with a bleach solution (the EPA recommends 5-25 drops of bleach per gallon)
· Keep sick individuals away from food preparation areas
· Avoid close contact with others when you are sick, and don’t share utensils or other items
· Wear disposable gloves while handling soiled items
· Immediately remove and wash clothes that may be contaminated with vomit or feces. Machine dry if possible.
It may be difficult to completely eliminate the risk of norovirus infection, but careful attention to hand and food hygiene will go a long way towards avoiding the stomach flu.
Joe Alton, MD
Check out Nurse Amy’s entire line of medical kits and individual supplies at her store at store.doomandbloom.net.