As an immunologist, come winter, I see a lot of children with viral infections, most often caused by respiratory viruses that affect the nose and throat -- and a lot of parents unhappy with the missed school days! These days mothers are coming to my office concerned with the tragic death of a child in New Jersey who contracted Enterovirus 68, even though this sad story is no longer in the headlines. And rightfully so it has the entire community on alert but the best defense against infectious diseases is reliable education on the best preventive practices and proactively implementing them.
There are good reasons for this cold-weather onset: first, children are indoors more -- and the indoor environment is the prime milieu for the spread of respiratory viruses. Children also have smaller airways so viruses move far more easily from the nose to the back of the throat and then into the ear canal. Finally, a child's immune system is still developing and the antibodies that fight infections in the respiratory tract aren't yet operating at "full speed."
But, there are key steps that parents can take to both prevent viral infections in the first place and, should your child come down with one, to aid in a much quicker recovery.
1. Air out your environment -- and your children, too! It is critical to "air out" every environment your child enters -- be it a school, office or home because outside air diminishes the stagnant air that leads to respiratory illness. Parents also need to "air out" their children's respiratory systems by making sure they play outdoors. The average American child spends less than 30 minutes outdoors nowadays -- at the very least increase it to an hour. The video games can wait! Recent research bears this out. 
2. Wipe down the remote control. If one of your children is sick make sure you wipe down the remote control. It is well known that in hotels the remote control is the major site for viral contamination. An over-the-counter sanitizing solution like Purell will do.
3. Create a strong hand-washing habit. Something as simple as a big plastic ball in a play space has enough germs on it to keep you at home caring for your child for days. Wash their hands with an antiseptic hand wash after every play outing. While you are doing this, train them to do the same throughout their lives -- and to become aware of the key germ-infested environments (i.e., public bathrooms, etc.).
4. Boost Immunity. Very little health-wise beats having a strong immune system. Some children are blessed with a potent immune system, but any child can strengthen his or hers. Many parents know that vitamins A, B and C are the core immunity boosters and don't forget vitamin D, too. For many healthful recipes for children, I recommend the blog SnackingOutsideTheBox.
5. When to call the pediatrician. A high fever of over 102 degrees or a fever over 100 degrees that lasts three days or more should be evaluated by a medical professional. Know that it is very common for a child to have a temperature of 101 degrees when an infection takes hold -- higher than an adult might have in a similar situation because a child hasn't yet built up the resistance that comes from years and years of "fighting" infections.
6. Hands off the antibiotics. I oftentimes see parents who press me to prescribe antibiotics at the first sign of a viral infection -- when, in fact, we in the medical community know that antibiotics do nothing to fight a viral infection. Indeed, recent studies show that they may indeed cause harm. 
7. Bringing down a fever. Advil and Tylenol are very good at bringing down your child's temperature and reducing symptoms, however, the tricky part is that the fever your child produces is instructing the immune system to send white blood cells to the infection site to take control and destroy the infection. Once your child's fever goes below 100 degrees, you may want to let the body heal itself.
8. Keep your children moving. A child with a viral infection lying in bed or on a couch is allowing mucus to settle back in the throat and chest. Encourage your child to get up and walk around the house if he or she feels well enough.
9. Vaccinate -- don't vacillate. One way to be proactive in building up your child's immune response to treatable viruses is the flu vaccine -- and today there are newer options that parents prefer.
The cold-weather season presents challenges to the health of children, and therefore, concerns parents, but a smart immune strategy can be the best antidote!
1. Arch Pediatric & Adolescent Medicine 2012: 166(8) 707-12 author Pooja S. Tandon MD, MPH et al.
2. Antibiotic and Asthma study: Annals of Allergy, Asthma and Immunology: May 2014 Dale Umetsko