Johns Hopkins Children’s Center pediatric infectious disease specialist Pranita Tamma, M.D., shares insights for parents.

How can I best protect my child against the flu?

First, with your pediatrician’s OK, have your child vaccinated. Added prevention is also key. Teach your child how to wash his or her hands when he or she is in school or away from home with either soap and water or an alcohol-based hand rub.

The flu virus spreads mainly by droplets when infected people cough, sneeze, or even talk, but it can be spread by touching surfaces on which one of those droplets has landed and then touching one’s nose, mouth or eyes. This is why hand washing is so important – both for the person with the flu and others around him or her. If someone in your household has the flu, ask your doctor if preemptive antiviral medication is an option for others in the home. Clean common surfaces like the kitchen counter, bathroom sink, light switches, door knobs, etc., frequently with household disinfectants.

If your child has the flu, keep him or her home from school, daycare and any other activities that could expose others to the virus. If your child needs to go outside of the house, he or she should wear a mask to reduce the likelihood of spreading the virus to others.

We urge that children six months and older be vaccinated, especially those at risk for complications from the flu. Your child’s pediatrician will know what’s best for your child, especially if there are preexisting conditions, including allergies, that require careful review.

What are its symptoms?

The symptoms of the seasonal flu include a fever (temperature of 100°F or greater), as well as a headache, sore throat, extreme fatigue and body aches, coughing, sneezing, runny nose, vomiting and/or diarrhea.

How should I treat it?

Consider giving your child acetaminophen (Tylenol) or ibuprofen (e.g. Advil or Motrin) as directed on the bottle for fevers, headache and body aches, or by your pediatrician. Have your child drink plenty of fluids to stay hydrated. This is especially important if your child has a high fever, vomiting or diarrhea. Keep your child apart from other members of the household, help him or her rest and keep him or her at home at least 24 hours after fever and other symptoms subside.

Do not share eating utensils, drinking glasses, washcloths, towels, beds, pillows, etc. until everyone in the household has been free of symptoms for five days.

Because the flu is caused by a virus it does NOT respond to antibiotics.

When should I seek medical treatment?

Children most likely to need medical treatment from their doctor for influenza infection are those who are very young or have serious medical conditions (such as asthma, cancer or lung disease, or who are on dialysis). If you think your child needs medical treatment, call your pediatrician’s office first. Your doctor may want to speak with you over the phone and recommend treatments rather than have you come into the office, where your child can infect other people.

How long is the incubation period and how long does the contagious phase last? 

Most healthy children and adults with the flu can infect others beginning about one day before developing any symptoms and up to seven days after the symptoms resolve. People with weakened immune systems can remain contagious for up to several weeks.

Is it possible to get the flu even after vaccination?

Getting a flu vaccine greatly reduces the risk of getting the flu but it does not guarantee that a child will not get the flu. In developing the vaccine, physicians and scientists make a best guess based on recent flu patterns to determine the most likely flu strains for the season. Unfortunately, there can be strains circulating in the environment that are not in the vaccine. The flu vaccine includes three strains of the influenza virus. The good news is that even if the vaccine strains and the circulating strains are not perfect matches, the vaccine can still provide some protection because viral strains share similarities. It takes about two weeks for the vaccine to elicit the proper protective response, so if someone is infected soon after receiving the vaccine, or if he or she was exposed to the virus before receiving the vaccine, symptoms can still develop.

Is the flu vaccine safe for kids with allergies?

Even though the flu vaccine contains egg protein, most children with egg and other food allergies can be immunized safely with a few basic precautions.

Children with established diagnoses of severe egg allergy should not be immunized without consulting a pediatric allergist. Most, however, can be vaccinated safely after a skin-prick test to the vaccine itself to gauge the risk for a reaction. Children with suspected yet unconfirmed allergies and those with mild egg allergies can usually be vaccinated in their pediatrician’s office.

An estimated 2 percent to 3 percent of U.S. children are allergic to eggs. Leaving them unprotected against the flu can lead to many unnecessary yet preventable infections and hospitalizations. Many children with food allergies also have asthma, putting them at even higher risk for complications from the flu. Pediatricians should make special efforts to vaccinate those at high risk for complications, according to the American Academy of Pediatrics (AAP).

Can children recently immunized “shed” the vaccine or virus to others? 

Such transmission of an attenuated influenza strain is very uncommon, perhaps because only low titers of vaccine virus are shed.