The Difference Between Influenza and Norovirus

The “Stomach Flu” – Influenza or Norovirus? Learn the Important Differences to Help Your Child Be Healthy

‘Tis the season. But not the time of year that anyone looks forward to: flu season. As students head back to school in the fall and colder weather emerges, so do the germs. Flu season in San Diego typically follows the national cycle, starting in the fall and lasting through February or March. This year, though the usual suspects have been joined by another viral outbreak, one that often is mistakenly referred to as a “stomach flu” but that has its own risks that parents in San Diego should familiarize themselves with. Its name? “Norovirus.”

Here are a few ways to tell the difference between influenza and norovirus. Having this information will help you determine how you should treat your child’s illness and what precautions you can take to protect yourself.

Factors	Influenza	Norovirus
Duration	One to two weeks	One to three days
Digestive symptoms	Nausea, vomiting, diarrhea	Nausea, stomach cramps, vomiting, diarrhea
Respiratory symptoms	Cough, sore throat, runny or stuffy nose	None
Other symptoms	Fever, headaches and/or body aches, chills, fatigue	Fever, chills, muscle aches, fatigue
Contagious period	From 1 day before showing symptoms up to 7 days after becoming sick	Within 1 day of illness up to several days after feeling better
How spread	Contact with sick person, particularly if they cough, sneeze, or talk within 6 feet of another person; possibly through contact with an item touched by a sick person, then touching your own mouth or nose	Direct contact with an infected person or their bodily fluids, eating food prepared by an infected person, through contact with an item touched by a sick person, then touching your own mouth or nose
How to avoid getting it	Sick individuals should stay home until they are no longer contagious and wash their hands frequently. Individuals caring for sick individuals should wash their hands and limit contact as much as possible. Disinfect surfaces touched by sick individuals.	Sick individuals should stay home until they are no longer contagious and wash their hands frequently. Individuals caring for sick individuals should wash their hands and limit contact as much as possible. Disinfect surfaces touched by sick individuals. Masks and gloves should be worn when cleaning up bodily fluids of infected person.
When to seek medical attention	Look for signs of complications such as pneumonia, bronchitis, sinus infections, and ear infections. People with chronic congestive heart failure should seek medical attention.	Look out for signs of severe dehydration, particularly in the young and the elderly. If symptoms do not clear up in 1 to 2 days, consult a medical professional.
How to treat	Rest, drink plenty of water and electrolyte beverages, use cool washcloths to reduce fever discomfort; decongestants, cough drops, and fever reducers may also be effective	Treatment options are very limited; generally, individuals should rest and drink plenty of fluids until symptoms pass within 1 or 2 days.

Parents in San Diego should particularly take note, as the so-called stomach flu has been hitting fairly close to home. San Diego has been no stranger to prior strains and outbreaks of the norovirus “stomach flu,” with a strain emerging in 2013 referred to as the Sydney strain. There were as many as 140 outbreaks of this newer strain in the U.S., the worst outbreak since 2009.

A Particularly Bad Flu Season

Aside from the norovirus, San Diego has seen a fairly rough regular flu season this year as well, with the Council of Community Clinics indicating it could be an especially long one. Usually, the flu season in San Diego starts to wind down and tapers off in March. But the numbers are not what they should be for this time period in February, and health experts are saying they continue to see larger numbers of flu patients for this time of year.

Also making the rounds is strep throat, a condition caused by streptococcal bacteria. This condition is distinguishable from the flu and norovirus in that it is primarily focused on the throat. Symptoms include the following:

Swollen and painful tonsils and lymph nodes
Bright red throat
Yellow or white spots on the back of the throat
Fever of more than 101 degrees F (38.3 C)
Less common: headache, belly pain, rash, vomiting, reduced appetite, muscle soreness.

This illness is just one more infection that is making this flu season in San Diego particularly brutal.

Why Do More People Get Sick When It’s Cold Out?

While the uptick in illnesses around this time of year tends to lead to speculation that cold weather is the cause of the increased sickness, the answer is actually a little more convoluted. Weather is a factor, but in a very indirect way. When it gets chilly outside, people have an increased tendency to stay indoors. Additionally, this also marks the season when students are in school, meaning a significant chunk of the population is in closer quarters.

All of this extra close contact lends itself to the spread of viruses. People are breathing the same air, touching the same surfaces, and thus exchanging plenty of germs in the process. Additionally, the air is drier both outside and inside during cold weather, which could allow viruses to pass more freely. These factors all help explain why a San Diego school could experience a big outbreak of the flu or the “stomach flu” among its student population.

Some ways you can help your children avoid getting sick this season:

Encourage them to wash their hands frequently.
Provide them with a small bottle of hand sanitizer in their backpacks, and a packet of tissues.
Pack lunches to avoid the spread from food handlers.
Discourage children from sharing food at lunch during this time of year.
Don’t force your children to go to school if they really are not feeling well, and learn to tell the difference between faking it and actual symptoms of illness.
Get you and your children vaccinated against the flu as soon as possible.